前沿速递 | NCS 集萃: 2025-04-03 期 [Up]

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『Abstract』The virus particles of human immunodeficiency virus type 1 (HIV-1) are released in an immature, non-infectious form. Proteolytic cleavage of the main structural polyprotein Gag into functional domains induces rearrangement into mature, infectious virions. In immature virus particles, the Gag membrane-binding domain, MA, forms a hexameric protein lattice that undergoes structural transition, following cleavage, into a distinct, mature MA lattice . The mechanism of MA lattice maturation is unknown. Here we show that released spacer peptide 2 (SP2), a conserved peptide of unknown function situated about 300 residues downstream of MA, binds MA to induce structural maturation. By high-resolution in-virus structure determination of MA, we show that MA does not bind lipid into a side pocket as previously thought , but instead binds SP2 as an integral part of the protein–protein interfaces that stabilize the mature lattice. Analysis of Gag cleavage site mutants showed that SP2 release is required for MA maturation, and we demonstrate that SP2 is sufficient to induce maturation of purified MA on lipid monolayers in vitro. SP2-triggered MA maturation correlated with faster fusion of virus with target cells. Our results reveal a new, unexpected interaction between two HIV-1 components, provide a high-resolution structure of mature MA, establish the trigger of MA structural maturation and assign function to the SP2 peptide.

『摘要』 人类免疫缺陷病毒1型(HIV-1)病毒颗粒以未成熟、无感染性的形式释放。主要结构多蛋白Gag经蛋白酶解切割成功能结构域后,会重新排列成为成熟、有感染性的病毒体。在未成熟的病毒颗粒中,Gag的膜结合结构域MA形成六聚体蛋白晶格,切割后发生结构转变,形成独特的、成熟的MA晶格。但MA晶格成熟的机制尚不清楚。本研究发现,位于MA下游约300个残基处的一个功能未知的保守肽——释放的间隔肽2(SP2)可与MA结合,诱导其结构成熟。通过对MA进行病毒体内高分辨率结构测定,本研究表明,MA并不像先前认为的那样将脂质结合到侧袋中,而是将SP2作为稳定成熟晶格的蛋白质-蛋白质界面不可或缺的一部分。对Gag切割位点突变体的分析表明,SP2的释放是MA成熟所必需的,本研究还证明,SP2足以在体外诱导脂质单层上纯化的MA成熟。SP2触发的MA成熟与病毒与目标细胞的更快融合相关。本研究结果揭示了HIV-1两种组分之间一种新的、意外的相互作用,提供了成熟MA的高分辨率结构,确定了触发MA结构成熟的因素,并赋予了SP2肽功能。
『总结』 本研究发现HIV-1中的SP2肽通过与MA结合诱导其结构成熟,揭示了HIV-1病毒颗粒成熟的新机制,并赋予了SP2肽新功能。
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『Abstract』Recent evidence indicates that the emergence of stone tool technology occurred before the appearance of the genus Homo and may potentially be traced back deep into the primate evolutionary line . Conversely, osseous technologies are apparently exclusive of later hominins from approximately 2 million years ago (Ma) , whereas the earliest systematic production of bone tools is currently restricted to European Acheulean sites 400–250 thousand years ago . Here we document an assemblage of bone tools shaped by knapping found within a single stratigraphic horizon at Olduvai Gorge dated to 1.5 Ma. Large mammal limb bone fragments, mostly from hippopotamus and elephant, were shaped to produce various tools, including massive elongated implements. Before our discovery, bone artefact production in pre-Middle Stone Age African contexts was widely considered as episodic, expedient and unrepresentative of early Homo toolkits. However, our results demonstrate that at the transition between the Oldowan and the early Acheulean, East African hominins developed an original cultural innovation that entailed a transfer and adaptation of knapping skills from stone to bone. By producing technologically and morphologically standardized bone tools, early Acheulean toolmakers unravelled technological repertoires that were previously thought to have appeared routinely more than 1 million years later.

『摘要』 最新的证据表明,石器技术的出现早于人类属(Homo)的出现,并可能追溯到灵长类动物进化树的更深处。相反,骨制技术显然是大约200万年前(Ma)以后的晚期人属物种所独有的,而目前已知最早的系统性骨制工具生产则局限于40万至25万年前的欧洲阿舍利文化遗址。本文报道了在奥杜瓦伊峡谷同一地层水平面发现的150万年前通过敲击法制造的骨制工具组合。这些工具主要使用大型哺乳动物(多为河马和大象)的肢骨碎片制成,包括各种工具,尤其是大型长条形工具。在我们的发现之前,人们普遍认为,中石器时代之前的非洲环境中,骨制品的生产是偶然的、权宜之计,并不能代表早期人类的工具组合。然而,我们的研究结果表明,在奥杜瓦伊文化和早期阿舍利文化之间的过渡时期,东非的人属物种发展出了一项原创性文化创新,即将敲击技术从石器转移到骨器上并加以适应。通过生产技术和形态上标准化的骨制工具,早期阿舍利文化的工具制造者展现了此前被认为要100多万年后才常规出现的技术水平。
『总结』 新研究发现表明,150万年前东非的人属物种已能制造骨制工具,这一技术创新将敲击技术从石器扩展到骨器,早于先前认知。
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『Abstract』Pathogen genomics can provide insights into underlying infectious disease transmission patterns , but new methods are needed to handle modern large-scale pathogen genome datasets and realize this full potential . In particular, genetically proximal viruses should be highly informative about transmission events as genetic proximity indicates epidemiological linkage. Here we use pairs of identical sequences to characterize fine-scale transmission patterns using 114,298 SARS-CoV-2 genomes collected through Washington State (USA) genomic sentinel surveillance with associated age and residence location information between March 2021 and December 2022. This corresponds to 59,660 sequences with another identical sequence in the dataset. We find that the location of pairs of identical sequences is highly consistent with expectations from mobility and social contact data. Outliers in the relationship between genetic and mobility data can be explained by SARS-CoV-2 transmission between postcodes with male prisons, consistent with transmission between prison facilities. We find that transmission patterns between age groups vary across spatial scales. Finally, we use the timing of sequence collection to understand the age groups driving transmission. Overall, this study improves our ability to use large pathogen genome datasets to understand the determinants of infectious disease spread.

『摘要』 病原体基因组学可以揭示潜在的传染病传播模式,但需要新的方法来处理现代大规模病原体基因组数据集并充分发挥其潜力。特别是,基因相近的病毒对于传播事件具有高度的信息价值,因为基因相近表明流行病学上的关联。本研究使用了2021年3月至2022年12月期间,通过美国华盛顿州的基因组哨点监测收集的114298个SARS-CoV-2基因组(及其相关的年龄和居住地信息),利用相同序列对来表征精细尺度的传播模式。这对应于数据集中有另一相同序列的59660个序列。我们发现,相同序列对的位置与根据流动性和社交接触数据的预期高度一致。遗传数据与流动性数据之间的关系中出现的异常值,可以通过含有男性监狱的邮政编码之间的SARS-CoV-2传播来解释,这与监狱设施之间的传播相一致。我们发现,不同年龄组之间的传播模式在空间尺度上存在差异。最后,我们通过序列收集的时间来了解推动传播的年龄组。总体而言,这项研究提高了我们利用大规模病原体基因组数据集来理解传染病传播决定因素的能力。
『总结』 本研究通过分析大量SARS-CoV-2基因组数据,揭示了传染病的精细传播模式,并提高了利用病原体基因组数据理解传染病传播因素的能力。
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『Abstract』The regulation of metabolism is vital to any organism and can be achieved by transcriptionally activating or repressing metabolic genes . Although many examples of transcriptional metabolic rewiring have been reported , a systems-level study of how metabolism is rewired in response to metabolic perturbations is lacking in any animal. Here we apply Worm Perturb-Seq (WPS)—a high-throughput method combining whole-animal RNA-interference and RNA-sequencing —to around 900 metabolic genes in the nematode Caenorhabditis elegans . We derive a metabolic gene regulatory network (mGRN) in which 385 perturbations are connected to 9,414 genes by more than 110,000 interactions. The mGRN has a highly modular structure in which 22 perturbation clusters connect to 44 gene expression programs. The mGRN reveals different modes of transcriptional rewiring from simple reaction and pathway compensation to rerouting and more complex network coordination. Using metabolic network modelling, we identify a design principle of transcriptional rewiring that we name the compensation–repression (CR) model. The CR model explains most transcriptional responses in metabolic genes and reveals a high level of compensation and repression in five core metabolic functions related to energy and biomass. We provide preliminary evidence that the CR model may also explain transcriptional metabolic rewiring in human cells.

『摘要』 代谢调节对所有生物体都至关重要,可通过转录激活或抑制代谢基因来实现。尽管已报道了许多转录代谢重编程的实例,但缺乏关于任何动物如何响应代谢扰动而进行代谢重编程的系统性研究。在这里,我们对线虫秀丽隐杆线虫中约900个代谢基因应用了Worm Perturb-Seq(WPS)——一种结合全动物RNA干扰和RNA测序的高通量方法。我们推导出一个代谢基因调控网络(mGRN),其中385个扰动通过超过11万个相互作用与9414个基因相连。mGRN具有高度模块化结构,其中22个扰动簇与44个基因表达程序相连。mGRN揭示了从简单反应、通路补偿到路径重定向和更复杂的网络协调等不同模式的转录重编程。通过代谢网络建模,我们发现了一种转录重编程的设计原则,我们将其命名为补偿-抑制(CR)模型。CR模型解释了大多数代谢基因的转录反应,并揭示了与能量和生物质相关的五个核心代谢功能中存在高水平的补偿和抑制。我们提供了初步证据,表明CR模型也可能解释人类细胞中的转录代谢重编程。
『总结』 本研究通过WPS方法构建了秀丽隐杆线虫的代谢基因调控网络,并发现了转录重编程的补偿-抑制模型,该模型可解释线虫及可能的人类细胞中的代谢转录反应。
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『Abstract』Metabolic flux, or the rate of metabolic reactions, is one of the most fundamental metrics describing the status of metabolism in living organisms. However, measuring fluxes across the entire metabolic network remains nearly impossible, especially in multicellular organisms. Computational methods based on flux balance analysis have been used with genome-scale metabolic network models to predict network-level flux wiring . However, such approaches have limited power because of the lack of experimental constraints. Here, we introduce a strategy that infers whole-animal metabolic flux wiring from transcriptional phenotypes in the nematode Caenorhabditis elegans . Using a large-scale Worm Perturb-Seq (WPS) dataset for roughly 900 metabolic genes , we show that the transcriptional response to metabolic gene perturbations can be integrated with the metabolic network model to infer a highly constrained, semi-quantitative flux distribution. We discover several features of adult C. elegans metabolism, including cyclic flux through the pentose phosphate pathway, lack of de novo purine synthesis flux and the primary use of amino acids and bacterial RNA as a tricarboxylic acid cycle carbon source, all of which we validate by stable isotope tracing. Our strategy for inferring metabolic wiring based on transcriptional phenotypes should be applicable to a variety of systems, including human cells.

『摘要』 代谢流,即代谢反应的速度,是描述生物体内代谢状态的最基本指标之一。然而,测量整个代谢网络中的代谢流仍然几乎不可能实现,尤其是在多细胞生物中。基于通量平衡分析的计算方法已结合基因组规模的代谢网络模型,用于预测网络水平的代谢流分布。然而,由于缺乏实验约束,此类方法的预测能力有限。在本文中,我们介绍了一种策略,可通过秀丽隐杆线虫(Caenorhabditis elegans)的转录表型来推断其全身代谢流分布。利用包含约900个代谢基因的大规模Worm Perturb-Seq(WPS)数据集,我们发现代谢基因扰动的转录反应可以与代谢网络模型相结合,以推断出受高度约束的半定量代谢流分布。我们发现了秀丽隐杆线虫成虫代谢的几个特征,包括戊糖磷酸途径中的循环代谢流、缺乏从头嘌呤合成代谢流以及主要利用氨基酸和细菌RNA作为三羧酸循环的碳源,并通过稳定同位素示踪对这些特征进行了验证。我们基于转录表型推断代谢流的策略应适用于包括人类细胞在内的多种系统。
『总结』 本文提出了一种基于秀丽隐杆线虫转录表型来推断全身代谢流分布的新策略,并利用大规模数据集验证了其有效性,发现了成虫代谢的若干新特征。
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『Abstract』Methane, the main component of natural and shale gas, is a significant carbon source for chemical synthesis. The direct partial oxidation of methane to liquid oxygenates under mild conditions is an attractive pathway, but the inertness of the molecule makes it challenging to achieve simultaneously high conversion and high selectivity towards a single target product. This difficulty is amplified when aiming for more valuable products that require C–C coupling . Whereas selective partial methane oxidation processes have thus typically generated C 1 oxygenates , recent reports have documented photocatalytic methane conversion to the C 2 oxygenate ethanol with low conversions but good-to-high selectivities . Here we show that the intramolecular junction photocatalyst covalent triazine-based framework-1 with alternating benzene and triazine motifs drives methane coupling and oxidation to ethanol with a high selectivity and significantly improved conversion. The heterojunction architecture not only enables efficient and long-lived separation of charges after their generation, but also preferential adsorption of H 2 O and O 2 to the triazine and benzene units, respectively. This dual-site feature separates C–C coupling to form ethane intermediates from the sites where •OH radicals are formed, thereby avoiding over-oxidation. When loaded with Pt to further boost performance, the molecular heterojunction photocatalyst generates ethanol in a packed-bed flow reactor with greatly improved conversion that results in an apparent quantum efficiency of 9.4%. We anticipate that further developing the ‘intramolecular junction’ approach will deliver efficient and selective catalysts for C–C coupling, pertaining, but not limited, to methane conversion to C 2+ chemicals.

『摘要』 甲烷是天然气和页岩气的主要成分,是化学合成的重要碳源。在温和条件下将甲烷直接部分氧化为液态含氧化合物是一条有吸引力的途径,但甲烷分子的惰性使得同时实现高转化率和对单一目标产物的高选择性具有挑战性。当目标产物为需要碳-碳偶联的更具价值的产品时,这种难度会更大。虽然选择性部分甲烷氧化过程通常会产生C1含氧化合物,但近期报告记录了在光催化作用下,甲烷可转化为C2含氧化合物乙醇,虽然转化率较低,但选择性良好至较高。本文研究表明,具有交替苯环和三嗪基序的共价三嗪基骨架-1分子内结光催化剂可驱动甲烷偶联和氧化生成乙醇,且具有高选择性和显著提高的转化率。该异质结结构不仅能够实现电荷生成后高效且持久的分离,而且还能使H2O和O2分别优先吸附于三嗪和苯环单元。这种双位点特性将形成乙烷中间体的碳-碳偶联与形成•OH自由基的位点分开,从而避免过度氧化。当负载铂以进一步提高性能时,该分子异质结光催化剂在填充床流动反应器中生成乙醇,转化率大幅提高,表观量子效率达到9.4%。我们预期,进一步发展“分子内结”方法将开发出高效且选择性的碳-碳偶联催化剂,适用于但不限于甲烷转化为C2+化学品。
『总结』 研究开发出了一种分子内结光催化剂,能够有效驱动甲烷偶联和氧化生成乙醇,具有高选择性和转化率,为甲烷转化为C2+化学品提供了新方法。
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『Abstract』Nucleophilic aromatic substitutions (S N Ar) are among the most widely used processes in the pharmaceutical and agrochemical industries , allowing convergent assembly of complex molecules through C–C and C–X (X = O, N, S) bond formation. S N Ar reactions are typically carried out using forcing conditions, involving polar aprotic solvents, stoichiometric bases and elevated temperatures, which do not allow for control over reaction selectivity. Despite the importance of S N Ar chemistry, there are only a handful of selective catalytic methods reported that rely on small organic hydrogen-bonding or phase-transfer catalysts . Here we establish a biocatalytic approach to stereoselective S N Ar chemistry by uncovering promiscuous S N Ar activity in a designed enzyme featuring an activated arginine . This activity was optimized over successive rounds of directed evolution to afford an engineered biocatalyst, S N Ar1.3, that is 160-fold more efficient than the parent and promotes the coupling of electron-deficient arenes with carbon nucleophiles with near-perfect stereocontrol (>99% enantiomeric excess (e.e.)). S N Ar1.3 can operate at a rate of 0.15 s , perform more than 4,000 turnovers and can accept a broad range of electrophilic and nucleophilic coupling partners, including those that allow construction of challenging 1,1-diaryl quaternary stereocentres. Biochemical, structural and computational studies provide insights into the catalytic mechanism of S N Ar1.3, including the emergence of a halide binding pocket shaped by key catalytic residues Arg124 and Asp125. This study brings a landmark synthetic reaction into the realm of biocatalysis to provide an efficient and versatile platform for catalytic S N Ar chemistry.

『摘要』 亲核芳香取代反应(S N Ar)是制药和农药行业中使用最广泛的过程之一,能够通过C–C和C–X(X=O、N、S)键的形成实现复杂分子的会聚组装。S N Ar反应通常在强制条件下进行,包括使用极性非质子溶剂、化学计量比的碱和高温,而这些条件无法控制反应的选择性。尽管S N Ar化学非常重要,但目前仅有少数依赖于小型有机氢键或相转移催化剂的选择性催化方法见诸报道。在本文中,我们发现了一种具有活化精氨酸的设计酶中的非专一性S N Ar活性,从而建立了一种立体选择性S N Ar化学的生物催化方法。经过多轮定向进化的优化,这种活性催生出了一种工程生物催化剂S N Ar1.3,其效率比原始催化剂高160倍,并能够在接近完美的立体控制(>99%对映体过量(e.e.))下促进缺电子芳烃与碳亲核试剂的偶联。S N Ar1.3的反应速率可达0.15 s-1,周转数超过4000,并且可以接受多种亲电和亲核偶联伙伴,包括那些能够构建具有挑战性的1,1-二芳基四元立体中心的偶联伙伴。生物化学、结构和计算研究为阐释S N Ar1.3的催化机制提供了见解,包括由关键催化残基Arg124和Asp125塑造的卤化物结合口袋的出现。本研究将一项具有里程碑意义的合成反应引入了生物催化领域,为催化S N Ar化学提供了一个高效且多功能的平台。
『总结』 本研究发现了一种具有活化精氨酸的设计酶能催化立体选择性S N Ar反应,并开发出高效生物催化剂S N Ar1.3,为S N Ar化学提供了生物催化的新平台。
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『Abstract』Inducing superconducting correlations in chiral edge states is predicted to generate topologically protected zero energy modes with exotic quantum statistics . Experimental efforts so far have focused on engineering interfaces between superconducting materials—typically amorphous metals—and semiconducting quantum Hall or quantum anomalous Hall systems. However, the strong interfacial disorder inherent in this approach can prevent the formation of isolated topological modes . An appealing alternative is to use low-density flat band materials in which the ground state can be tuned between intrinsic superconducting and quantum anomalous Hall states using only the electric field effect. However, quantized transport and superconductivity have not been simultaneously achieved. Here we show that rhombohedral tetralayer graphene aligned to a hexagonal boron nitride substrate hosts a quantized anomalous Hall state at superlattice filling ν = −1 as well as a superconducting state at ν ≈ −3.5 at zero magnetic field. Gate voltage can also be used to actuate non-volatile switching of the chirality in the quantum anomalous Hall state , allowing, in principle, arbitrarily reconfigurable networks of topological edge modes in locally gated devices. Thermodynamic compressibility measurements further show a topologically ordered fractional Chern insulator at ν = 2/3 (ref. )—also stable at zero magnetic field—enabling proximity coupling between superconductivity and fractionally charged edge modes. Finally, we show that, as in rhombohedral bi- and trilayers , integrating a transition metal dichalcogenide layer to the heterostructure nucleates a new superconducting pocket , while leaving the topology of the ν = −1 quantum anomalous Hall state intact. Our results pave the way for a new generation of hybrid interfaces between superconductors and topological edge states in the low disorder limit.

『摘要』 在手性边缘态中诱导超导相关性,有望产生具有奇异量子统计特性的拓扑保护零能模。迄今为止的实验工作主要集中在构建超导材料(通常为非晶金属)与半导体量子霍尔或量子反常霍尔系统之间的界面。然而,这种方法固有的强界面无序可能会阻碍孤立拓扑模的形成。一个颇具吸引力的替代方案是使用低密度平带材料,在这种材料中,仅利用电场效应就可以将基态在固有超导态和量子反常霍尔态之间进行调谐。然而,量子化传输和超导性尚未同时实现。在此,我们发现,当菱形四层石墨烯与六方氮化硼衬底对齐时,在超晶格填充ν=−1时表现出量子化的反常霍尔态,同时在ν≈−3.5、零磁场条件下表现出超导态。门电压还可以用于驱动量子反常霍尔态中手性的非易失性切换,原则上,这允许在局部栅控器件中实现拓扑边缘模的任意可重构网络。热力学可压缩性测量进一步显示在ν=2/3时存在一个拓扑有序的分数陈绝缘体(同样在零磁场下稳定),从而实现了超导性与分数电荷边缘模之间的邻近耦合。最后,我们的研究表明,与菱形双层和三层石墨烯一样,在异质结构中整合一层过渡金属二硫化物会催生一个新的超导区域,同时保持ν=−1量子反常霍尔态的拓扑性质不变。我们的研究结果为在低无序极限下构建超导体与拓扑边缘态之间的新型混合界面铺平了道路。
『总结』 本研究通过在菱形四层石墨烯与六方氮化硼衬底的对齐结构中,实现了量子化反常霍尔态与超导态的共存,为构建低无序极限下的超导体与拓扑边缘态新型混合界面提供了新途径。
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『Abstract』Pan-genomics and genome-editing technologies are revolutionizing breeding of global crops . A transformative opportunity lies in exchanging genotype-to-phenotype knowledge between major crops (that is, those cultivated globally) and indigenous crops (that is, those locally cultivated within a circumscribed area) to enhance our food system. However, species-specific genetic variants and their interactions with desirable natural or engineered mutations pose barriers to achieving predictable phenotypic effects, even between related crops . Here, by establishing a pan-genome of the crop-rich genus Solanum and integrating functional genomics and pan-genetics, we show that gene duplication and subsequent paralogue diversification are major obstacles to genotype-to-phenotype predictability. Despite broad conservation of gene macrosynteny among chromosome-scale references for 22 species, including 13 indigenous crops, thousands of gene duplications, particularly within key domestication gene families, exhibited dynamic trajectories in sequence, expression and function. By augmenting our pan-genome with African eggplant cultivars and applying quantitative genetics and genome editing, we dissected an intricate history of paralogue evolution affecting fruit size. The loss of a redundant paralogue of the classical fruit size regulator CLAVATA3 ( CLV3 ) was compensated by a lineage-specific tandem duplication. Subsequent pseudogenization of the derived copy, followed by a large cultivar-specific deletion, created a single fused CLV3 allele that modulates fruit organ number alongside an enzymatic gene controlling the same trait. Our findings demonstrate that paralogue diversifications over short timescales are underexplored contingencies in trait evolvability. Exposing and navigating these contingencies is crucial for translating genotype-to-phenotype relationships across species.

『摘要』 泛基因组和基因组编辑技术正在彻底改变全球作物的育种方式。在主要作物(即全球种植的作物)和本土作物(即在特定地区内本地种植的作物)之间交流基因型到表现型的知识,为提高我们的粮食系统提供了一个变革性的机会。然而,即使在相关作物之间,特定物种的遗传变异及其与理想自然突变或工程突变之间的相互作用也阻碍了实现可预测的表现型效应。在这里,我们通过建立作物种类丰富的茄属植物的泛基因组,并结合功能基因组和泛遗传学,发现基因重复和随后的旁系同源基因分化是基因型到表现型可预测性的主要障碍。尽管在包括13种本土作物在内的22个物种的染色体级参考基因组中,基因的大范围共线性得到了广泛保存,但在关键驯化基因家族中,尤其是在这些关键驯化基因家族内部,数千个基因重复在序列、表达和功能上展现出动态的演变轨迹。我们通过用非洲茄子品种扩充泛基因组,并运用数量遗传学和基因组编辑技术,剖析了影响果实大小的旁系同源基因复杂进化史。经典果实大小调节因子CLAVATA3(CLV3)的一个冗余旁系同源基因的丢失被一个谱系特异性串联重复所补偿。随后,衍生的拷贝发生假基因化,接着发生一个大的品种特异性缺失,形成了一个单一的融合CLV3等位基因,该等位基因与一个控制相同性状的酶基因一起调节果实器官的数量。我们的研究结果表明,短时间内旁系同源基因的分化是性状进化能力中被低估的偶然因素。揭示和探究这些偶然因素对于跨物种转化基因型到表现型的关系至关重要。
『总结』 本研究通过茄属植物泛基因组及功能基因组学研究,发现基因重复和旁系同源基因分化是阻碍基因型到表现型预测的主要障碍,强调了揭示和利用短时间内旁系同源基因分化这一被低估的偶然因素对于跨物种性状预测的重要性。
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『Abstract』The current opioid overdose epidemic highlights the urgent need to develop safer and more effective treatments for chronic pain . Cannabinoid receptor type 1 (CB1) is a promising non-opioid target for pain relief, but its clinical use has been limited by centrally mediated psychoactivity and tolerance. We overcame both issues by designing peripherally restricted CB1 agonists that minimize arrestin recruitment. We achieved these goals by computationally designing positively charged derivatives of the potent CB1 agonist MDMB-Fubinaca . We designed these ligands to occupy a cryptic pocket identified through molecular dynamics simulations—an extended binding pocket that opens rarely and leads to the conserved signalling residue D (ref. ). We used structure determination, pharmacological assays and molecular dynamics simulations to verify the binding modes of these ligands and to determine the molecular mechanism by which they achieve this dampening of arrestin recruitment. Our lead ligand, VIP36, is highly peripherally restricted and demonstrates notable efficacy in three mouse pain models, with 100-fold dose separation between analgesic efficacy and centrally mediated side effects. VIP36 exerts analgesic efficacy through peripheral CB1 receptors and shows limited analgesic tolerance. These results show how targeting a cryptic pocket in a G-protein-coupled receptor can lead to enhanced peripheral selectivity, biased signalling, desired in vivo pharmacology and reduced adverse effects. This has substantial implications for chronic pain treatment but could also revolutionize the design of drugs targeting other G-protein-coupled receptors.

『摘要』 当前的阿片类药物过量流行突显了开发更安全、更有效的慢性疼痛治疗方法的迫切需求。大麻素受体1(CB1)是一种很有前景的非阿片类镇痛靶点,但其临床应用一直受到中枢介导的精神活性和耐受性的限制。我们通过设计外周限制性CB1激动剂解决了这两个问题,该类激动剂可最大限度地减少逮捕蛋白的募集。我们通过计算设计,合成了强效CB1激动剂MDMB-Fubinaca的带正电荷衍生物,实现了这一目标。我们设计这些配体是为了占据通过分子动力学模拟发现的一个隐秘口袋——一个很少打开且导向保守信号残基D的扩展结合口袋。我们使用结构测定、药理学检测和分子动力学模拟来验证这些配体的结合模式,并确定它们实现抑制逮捕蛋白募集的分子机制。我们的主要配体VIP36在外周具有高度的限制性,并在三种小鼠疼痛模型中显示出显著的疗效,镇痛疗效与中枢介导的副作用之间的剂量分离达100倍。VIP36通过外周CB1受体发挥镇痛作用,且镇痛耐受性有限。这些结果表明,靶向G蛋白偶联受体中的隐秘口袋如何提高外周选择性、偏向性信号传导、实现所需的体内药理作用并减少不良反应。这对慢性疼痛治疗具有重要意义,但也可能彻底改变靶向其他G蛋白偶联受体的药物设计。
『总结』 研究发现靶向G蛋白偶联受体隐秘口袋的外周限制性CB1激动剂VIP36能高效镇痛且副作用少,为慢性疼痛治疗提供了新策略。
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『Abstract』A supersolid is a counter-intuitive phase of matter in which its constituent particles are arranged into a crystalline structure, yet they are free to flow without friction. This requires the particles to share a global macroscopic phase while being able to reduce their total energy by spontaneous, spatial self-organization. The existence of the supersolid phase of matter was speculated more than 50 years ago . However, only recently has there been convincing experimental evidence, mainly using ultracold atomic Bose–Einstein condensates (BECs) coupled to electromagnetic fields. There, various guises of the supersolid were created using atoms coupled to high-finesse cavities , with large magnetic dipole moments , and spin–orbit-coupled, two-component systems showing stripe phases . Here we provide experimental evidence of a new implementation of the supersolid phase in a driven-dissipative, non-equilibrium context based on exciton–polaritons condensed in a topologically non-trivial, bound state in the continuum (BiC) with exceptionally low losses, realized in a photonic-crystal waveguide. We measure the density modulation of the polaritonic state indicating the breaking of translational symmetry with a precision of several parts in a thousand. Direct access to the phase of the wavefunction allows us to also measure the local coherence of the supersolid. We demonstrate the potential of our synthetic photonic material to host phonon dynamics and a multimode excitation spectrum.

『摘要』 超固体是一种反直观的物质状态,在这种状态下,其组成粒子排列成晶体结构,但它们可以自由地无摩擦流动。这要求粒子共享一个全局宏观相位,同时能够通过自发、空间自组织来降低其总能量。50多年前,人们就推测存在超固态这种物质状态。然而,直到最近才有了令人信服的实验证据,主要是利用耦合到电磁场的超冷原子玻色-爱因斯坦凝聚体(BEC)。在这些实验中,利用耦合到高精细度腔的原子、具有大磁偶极矩的原子以及自旋-轨道耦合的两组分系统(表现出条纹相)创建了超固体的各种形态。在这里,我们提供了实验证据,证明了一种在驱动-耗散、非平衡环境下超固体相的新实现方法,该方法基于在光子晶体波导中实现的、具有极低损失的、拓扑非平凡的连续体(BiC)束缚态中凝聚的激子-极化激元。我们测量了极化激元状态的密度调制,表明平移对称性被破坏,精度达到千分之几。直接访问波函数的相位还使我们能够测量超固体的局部相干性。我们展示了这种合成光子材料在承载声子动力学和多模激发谱方面的潜力。
『总结』 本研究通过实验证明了在驱动-耗散、非平衡环境下,利用光子晶体波导中凝聚的激子-极化激元,实现了超固体相,并测量了其密度调制和局部相干性。
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『Abstract』Seawater electrolysis powered by renewable electricity provides an attractive strategy for producing green hydrogen . However, direct seawater electrolysis faces many challenges, primarily arising from corrosion and competing reactions at the anode caused by the abundance of halide ions (Cl , Br ) in seawater . Previous studies on seawater electrolysis have mainly focused on the anode development, because the cathode operates at reducing potentials, which is not subject to electrode dissolution or chloride corrosion reactions during seawater electrolysis . However, renewable energy sources are intermittent, variable and random, which cause frequent start–shutdown operations if renewable electricity is used to drive seawater electrolysis. Here we first unveil dynamic evolution and degradation of seawater splitting cathode in intermittent electrolysis and, accordingly, propose construction of a catalyst’s passivation layer to maintain the hydrogen evolution performance during operation. An in situ-formed phosphate passivation layer on the surface of NiCoP–Cr 2 O 3 cathode can effectively protect metal active sites against oxidation during frequent discharge processes and repel halide ion adsorption on the cathode during shutdown conditions. We demonstrate that electrodes optimized using this design strategy can withstand fluctuating operation at 0.5 A cm for 10,000 h in alkaline seawater, with a voltage increase rate of only 0.5% khr . The newly discovered challenge and our proposed strategy herein offer new insights to facilitate the development of practical seawater splitting technologies powered by renewable electricity.

『摘要』 利用可再生电力进行海水电解为生产绿色氢气提供了一种有吸引力的策略。然而,直接海水电解面临许多挑战,这些挑战主要源于海水中丰富的卤离子(Cl、Br)在阳极引起的腐蚀和竞争反应。以往关于海水电解的研究主要集中在阳极的开发上,因为阴极在还原电位下工作,在海水电解过程中不会发生电极溶解或氯化物腐蚀反应。然而,可再生能源是间歇性的、可变的和随机的,如果使用可再生电力来驱动海水电解,会导致频繁的启动-停机操作。在此,我们首次揭示了间歇电解过程中海水裂解阴极的动态演化和降解,并据此提出构建催化剂的钝化层,以维持运行过程中的析氢性能。在NiCoP–Cr 2 O 3 阴极表面原位形成的磷酸盐钝化层,可以有效保护金属活性位点在频繁放电过程中免受氧化,并在停机状态下排斥卤离子在阴极上的吸附。我们证明,采用这种设计策略优化的电极可以在碱性海水中以0.5 A/cm²的波动条件下运行10000小时,电压升高率仅为0.5%/khr。新发现的挑战和我们在此提出的策略为促进可再生电力驱动的海水裂解技术的实用化发展提供了新的见解。
『总结』 本研究揭示了间歇电解对海水裂解阴极的影响,通过构建催化剂钝化层提升了阴极在波动条件下的稳定性,为可再生电力驱动的海水裂解技术发展提供了新策略。
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『Abstract』Carbohydrates are an abundant, inexpensive and renewable biomass feedstock that could be a cornerstone for sustainable chemical manufacturing, but scalable and environmentally friendly methods that leverage these feedstocks are lacking. For example, 1-allyl sorbitol is the foundational building block for the polypropylene clarifying agent Millad NX 8000, which is produced on the multi-metric ton scale annually, but the manufacturing process at present requires superstoichiometric amounts of tin . The NX 8000 additives dominate about 80% of the global clarified polypropylene market and are used in concentrations of 0.01–1% during polypropylene production to improve its transparency and resistance to high temperatures, translating to 300–30,000 metric tons annually. The market volume of polypropylene in 2022 was approximately 79.01 million metric tons (MMT), with demand expected to rise by nearly 33% to 105 MMT by 2030 (ref. ). The cost and sustainability benefits of clarified polypropylene are driving this demand, necessitating more clarifying agents . Here we report a high-yielding allylation of unprotected carbohydrates in water using a catalytic amount of indium metal and either allylboronic acid or the pinacol ester (allylBpin) as donors. Aldohexoses, aminohexoses, ketohexoses and aldopentoses are all allylated in high yield under mild conditions and the indium metal is recoverable and reusable with no loss of catalytic activity. Leveraging these features, this process was translated to a scalable continuous synthesis of 1-allyl sorbitol in flow with high yield and productivity through Bayesian optimization of reaction parameters.

『摘要』 碳水化合物是一种丰富、廉价且可再生的生物质原料,有可能成为可持续化学制造的基石,但目前缺乏可扩展且环保的利用这些原料的方法。例如,1-烯丙基山梨醇是聚丙烯澄清剂Millad NX 8000的基础构件,其年产量达数公吨,但目前的制造工艺需要超化学计量的锡。NX 8000添加剂在全球澄清聚丙烯市场中约占80%的份额,在聚丙烯生产过程中以0.01~1%的浓度使用,以提高其透明度和耐高温性,换算下来每年用量为3~3万吨。2022年,聚丙烯的市场容量约为7901万吨,预计到2030年需求将增长近33%,达到1.05亿吨。澄清聚丙烯的成本效益和可持续性推动了这一需求,因此需要更多的澄清剂。本文报道了一种在水中使用催化量的铟金属以及烯丙基硼酸或频哪醇酯(烯丙基Bpin)作为给体,对未保护碳水化合物进行高收率烯丙基化的方法。在温和条件下,醛己糖、氨基己糖、酮己糖和醛戊糖均以高收率进行烯丙基化,且铟金属可回收并重复使用,催化活性不降低。利用这些特性,通过贝叶斯优化反应参数,将这一过程转化为一种可连续合成1-烯丙基山梨醇的方法,且产量高、生产率高。
『总结』 本文介绍了一种在水中利用铟金属催化未保护碳水化合物进行高收率烯丙基化的新方法,并成功应用于1-烯丙基山梨醇的可扩展连续合成,以满足对澄清聚丙烯日益增长的需求。
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『Abstract』Superconducting (SC) states that break space-group symmetries of the underlying crystal can exhibit nontrivial spatial modulation of the order parameter. Previously, such states were intimately associated with the breaking of translational symmetry , resulting in the density-wave orders , with wavelengths spanning several unit cells . However, a related basic concept has long been overlooked : when only intra-unit-cell symmetries of the space group are broken, the SC states can show a distinct type of nontrivial modulation preserving long-range lattice translation. Here we refer to this new concept as the pair density modulation (PDM) and report the first observation of a PDM state in exfoliated thin flakes of the iron-based superconductor FeTe 0.55 Se 0.45 . Using scanning tunnelling microscopy (STM), we discover robust SC gap modulation with the wavelength corresponding to the lattice periodicity and the amplitude exceeding 30 % of the gap average. Notably, we find that the observed modulation originates from the large difference in SC gaps on the two nominally equivalent iron sublattices. The experimental findings, backed up by model calculations, suggest that, in contrast to the density-wave orders, the PDM state is driven by the interplay of sublattice symmetry breaking and a peculiar nematic distortion specific to the thin flakes. Our results establish new frontiers for exploring the intertwined orders in strong-correlated electronic systems and open a new chapter for iron-based superconductors.

『摘要』 超导体(SC)若打破其基础晶体的空间群对称性,则会表现出非平庸的序参量空间调制。此前,这类状态一直与平移对称性的破坏密切相关,导致形成密度波序,其波长跨越多个晶胞。然而,一个相关的基本概念长期以来一直被忽视:当仅破坏空间群的晶胞内对称性时,超导体可以表现出一种保持长程晶格平移性的不同非凡调制类型。在此,我们将这一新概念称为对密度调制(PDM),并报告了在铁基超导体FeTe0.55Se0.45的剥离薄片中首次观察到PDM状态。使用扫描隧道显微镜(STM),我们发现了稳健的超导能隙调制,其波长与晶格周期相对应,振幅超过能隙平均值的30%。值得注意的是,我们发现观察到的调制源于名义上等效的两个铁子晶格上超导能隙的巨大差异。实验结果得到了模型计算的支持,表明与密度波序不同,PDM状态是由子晶格对称性破坏和薄片特有的特殊向列扭曲之间的相互作用驱动的。我们的研究结果为探索强相关电子系统中的交织序开辟了新领域,并为铁基超导体开启了新篇章。
『总结』 研究人员发现,当超导体仅打破晶胞内对称性时,可展现一种保持长程平移性的对密度调制(PDM)新状态,并在铁基超导体FeTe0.55Se0.45薄片中首次观测到此状态。
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『Abstract』Deracemization is an emerging strategy for generating enantioenriched compounds wherein the two enantiomers of a readily available racemic starting material are transformed into a single enantiomer, typically through the action of a light-induced catalyst . Excellent proof of principle for this potentially powerful approach to asymmetric catalysis has been described ; nevertheless, substantial challenges have not yet been addressed, including the exploitation of carbon–heteroatom (rather than only carbon–hydrogen and carbon–carbon) bond cleavage to achieve deracemization, as well as the development of processes that provide broad classes of useful enantioenriched compounds and tetrasubstituted stereocentres. Here we describe a straightforward method that addresses these challenges, using a chiral copper catalyst, generated in situ from commercially available components, to achieve the photoinduced deracemization of tertiary (and secondary) alkyl halides through carbon–halogen bond cleavage. Mechanistic studies (including the independent synthesis of postulated intermediates, photophysical, spectroscopic and reactivity studies, and density functional theory calculations) provide support for the key steps and intermediates in our proposed catalytic cycle, as well as insight into the origin of enantioselectivity.

『摘要』 去消旋化是一种新兴策略,用于生成对映体富集的化合物,在这种策略中,易得的外消旋起始原料的两种对映体在光诱导催化剂的作用下被转化为一种对映体。这种可能具有强大功能的不对称催化方法已有良好的概念验证;然而,尚未解决重大挑战,包括利用碳-杂原子(而不仅仅是碳-氢键和碳-碳键)键断裂来实现去消旋化,以及开发能够提供广泛类别的有用对映体富集化合物和四取代立体中心的方法。在这里,我们描述了一种简单的方法来解决这些挑战,该方法使用由市售组分原位生成的手性铜催化剂,通过碳-卤键断裂来实现叔(和仲)烷基卤化物的光诱导去消旋化。机理研究(包括假定中间体的独立合成、光物理、光谱和反应性研究以及密度泛函理论计算)为我们提出的催化循环中的关键步骤和中间体提供了支持,并深入了解了对映选择性的起源。
『总结』 本研究报道了一种使用手性铜催化剂通过光诱导和碳-卤键断裂实现叔(和仲)烷基卤化物去消旋化的新方法,并提供了机理研究的支持。
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『Abstract』Hardware implementations of artificial neural networks (ANNs)—the most advanced of which are made of millions of electronic neurons interconnected by hundreds of millions of electronic synapses—have achieved higher energy efficiency than classical computers in some small-scale data-intensive computing tasks . State-of-the-art neuromorphic computers, such as Intel’s Loihi or IBM’s NorthPole , implement ANNs using bio-inspired neuron- and synapse-mimicking circuits made of complementary metal–oxide–semiconductor (CMOS) transistors, at least 18 per neuron and six per synapse. Simplifying the structure and size of these two building blocks would enable the construction of more sophisticated, larger and more energy-efficient ANNs. Here we show that a single CMOS transistor can exhibit neural and synaptic behaviours if biased in a specific (unconventional) manner. By connecting one additional CMOS transistor in series, we build a versatile 2-transistor-cell that exhibits adjustable neuro-synaptic response (which we named neuro-synaptic random access memory cell, or NS-RAM cell). This electronic performance comes with a yield of 100% and an ultra-low device-to-device variability, owing to the maturity of the silicon CMOS platform used—no materials or devices alien to the CMOS process are required. These results represent a short-term solution for the implementation of efficient ANNs and an opportunity in terms of CMOS circuit design and optimization for artificial intelligence applications.

『摘要』 人工神经网络(ANNs)的硬件实现——其中最先进的由数百万个电子神经元组成,这些神经元通过数十亿个电子突触相互连接——在某些小规模的数据密集型计算任务中已经实现了比传统计算机更高的能效。最先进的神经形态计算机,如英特尔的Loihi或IBM的NorthPole,使用由互补金属氧化物半导体(CMOS)晶体管制成的、模仿生物神经元和突触的电路来实现ANNs,每个神经元至少需要18个晶体管,每个突触需要6个。简化这两个构建模块的结构和尺寸将能够构建更复杂、更大、更节能的ANNs。在这里,我们证明了如果以特定的(非常规的)方式偏置,单个CMOS晶体管就可以表现出神经和突触行为。通过串联一个额外的CMOS晶体管,我们构建了一个多功能双晶体管单元,该单元表现出可调节的神经突触响应(我们称之为神经突触随机存取存储单元,或NS-RAM单元)。由于所使用的硅CMOS平台已经成熟——不需要CMOS工艺以外的材料或器件,因此该电子元件的良率为100%,且器件间的差异性极低。这些结果为高效ANNs的实现提供了短期解决方案,并为人工智能应用的CMOS电路设计和优化提供了机遇。
『总结』 研究发现通过特定方式偏置,单个CMOS晶体管可表现神经和突触行为,为高效ANNs实现提供了新方法和CMOS电路优化机遇。
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『Abstract』A quantum network provides an infrastructure that connects quantum devices with revolutionary computing, sensing and communication capabilities. A quantum satellite constellation offers a solution to facilitate the quantum network on a global scale . The Micius satellite has verified the feasibility of satellite quantum communications ; however, scaling up quantum satellite constellations is challenging, requiring small lightweight satellites, portable ground stations and real-time secure key exchange. Here we tackle these challenges and report the development of a quantum microsatellite capable of performing space-to-ground quantum key distribution using portable ground stations. The microsatellite payload weighs approximately 23 kilograms, and the portable ground station weighs about 100 kilograms, representing reductions by more than 1 and 2 orders of magnitude, respectively. Using this set-up, we demonstrate satellite-based quantum key distribution with multiple ground stations and achieve the sharing of up to 1.07 million bits of secure keys during a single satellite pass. In addition, we multiplex bidirectional satellite–ground optical communication with quantum communication, enabling key distillation and secure communication in real time. Also, a secret key, enabling one-time pad encryption of images, is created between China and South Africa at locations separated by over 12,900 kilometres on Earth. The compact quantum payload can be readily assembled on existing space stations or small satellites , paving the way for a satellite-constellation-based quantum and classical network for widespread real-life applications.

『摘要』 量子网络为连接具有革命性计算、传感和通信能力的量子设备提供了基础设施。量子卫星星座为解决全球范围内量子网络的部署问题提供了方案。墨子号卫星已经验证了卫星量子通信的可行性;然而,扩大量子卫星星座的规模颇具挑战,需要小型轻质卫星、便携式地面站和实时安全密钥交换。本文应对这些挑战,报告了一颗能够利用便携式地面站执行空地量子密钥分发的量子微纳卫星的研发情况。该微纳卫星的有效载荷重约23公斤,便携式地面站重约100公斤,分别减重了一个和两个数量级以上。利用该装置,本文展示了与多个地面站进行的基于卫星的量子密钥分发,并在卫星单次过境期间实现了多达107万比特安全密钥的共享。此外,本文将双向卫星—地面光通信与量子通信进行复用,实现了实时密钥提取和安全通信。同时,在地球上相距12900多公里的中国和南非之间创建了一个密钥,能够对图像进行一次一密加密。紧凑型量子有效载荷可以很容易地装配到现有的空间站或小型卫星上,为基于卫星星座的量子和经典网络在广泛的现实生活应用中铺平道路。
『总结』 本文研发了一种量子微纳卫星,利用便携式地面站实现空地量子密钥分发,为构建全球量子网络提供了可行方案,并成功实现了多个技术突破。
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『Abstract』Temporary pacemakers are essential for the care of patients with short-lived bradycardia in post-operative and other settings . Conventional devices require invasive open-heart surgery or less invasive endovascular surgery, both of which are challenging for paediatric and adult patients . Other complications include risks of infections, lacerations and perforations of the myocardium, and of displacements of external power supplies and control systems. Here we introduce a millimetre-scale bioresorbable optoelectronic system with an onboard power supply and a wireless, optical control mechanism with generalized capabilities in electrotherapy and specific application opportunities in temporary cardiac pacing. The extremely small sizes of these devices enable minimally invasive implantation, including percutaneous injection and endovascular delivery. Experimental studies demonstrate effective pacing in mouse, rat, porcine, canine and human cardiac models at both single-site and multi-site locations. Pairing with a skin-interfaced wireless device allows autonomous, closed-loop operation upon detection of arrhythmias. Further work illustrates opportunities in combining these miniaturized devices with other medical implants, with an example of arrays of pacemakers for individual or collective use on the frames of transcatheter aortic valve replacement systems, to provide unique solutions that address risks for atrioventricular block following surgeries. This base technology can be readily adapted for a broad range of additional applications in electrotherapy, such as nerve and bone regeneration, wound therapy and pain management.

『摘要』 临时心脏起搏器对于术后等情况下出现短暂性心动过缓的患者护理至关重要。传统装置需要开展侵入性开胸手术或创伤较小的血管内手术,这对儿童和成年患者都具有挑战性。其他并发症还包括感染、心肌撕裂和穿孔以及外部电源和控制系统移位等风险。本文介绍了一种毫米级可生物吸收的光电系统,该系统搭载了板载电源和无线光学控制机制,具有通用的电疗能力和临时心脏起搏的具体应用机会。这类装置的尺寸极小,可实现微创植入,包括经皮注射和血管内递送。实验研究表明,该系统能够在小鼠、大鼠、猪、犬和人体心脏模型的单一部位和多部位实现有效起搏。当与皮肤界面的无线设备配对时,可自主实现闭环操作以检测心律失常。进一步研究展示了将这些微型装置与其他医疗植入物结合使用的机会,例如在经导管主动脉瓣置换系统的框架上单独或组合使用起搏器阵列,为应对术后房室传导阻滞的风险提供了独特解决方案。这项基础技术可轻松适应电疗领域的广泛其他应用,如神经和骨骼再生、伤口治疗和疼痛管理。
『总结』 本文介绍了一种毫米级可生物吸收的光电系统用于临时心脏起搏,实现了微创植入和有效的起搏效果,并展示了与其他医疗植入物结合使用的广阔前景。
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『Abstract』Two-dimensional (2D) metals are appealing for many emergent phenomena and have recently attracted research interests . Unlike the widely studied 2D van der Waals (vdW) layered materials, 2D metals are extremely challenging to achieve, because they are thermodynamically unstable . Here we develop a vdW squeezing method to realize diverse 2D metals (including Bi, Ga, In, Sn and Pb) at the ångstrom thickness limit. The achieved 2D metals are stabilized from a complete encapsulation between two MoS 2 monolayers and present non-bonded interfaces, enabling access to their intrinsic properties. Transport and Raman measurements on monolayer Bi show excellent physical properties, for example, new phonon mode, enhanced electrical conductivity, notable field effect and large nonlinear Hall conductivity. Our work establishes an effective route for implementing 2D metals, alloys and other 2D non-vdW materials, potentially outlining a bright vision for a broad portfolio of emerging quantum, electronic and photonic devices.

『摘要』 二维(2D)金属因众多新兴现象而具有吸引力,并且最近引发了研究兴趣。不同于被广泛研究的二维范德华(vdW)层状材料,二维金属的制备极具挑战性,因为它们在热力学上不稳定。本文开发了一种范德华挤压方法,在埃米级厚度极限下实现了多种二维金属(包括铋、镓、铟、锡和铅)。所制得的二维金属被两层二硫化钼(MoS2)完全封装而稳定存在,并且呈现出非键合界面,从而可以探究其本征特性。对单层铋进行的传输和拉曼测量表明,其具有优异的物理特性,例如新声子模式、增强的导电性、显著的场效应和较大的非线性霍尔电导率。本研究为制备二维金属、合金和其他二维非范德华材料开辟了一条有效途径,有可能为一系列新兴的量子、电子和光子器件勾勒出一个光明的前景。
『总结』 本研究通过范德华挤压方法成功制备了多种二维金属,并发现单层铋具有优异的物理特性,为二维材料的研究和应用开辟了新途径。
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『Abstract』The goal of future quantum networks is to enable new internet applications that are impossible to achieve using only classical communication . Up to now, demonstrations of quantum network applications and functionalities on quantum processors have been performed in ad hoc software that was specific to the experimental setup, programmed to perform one single task (the application experiment) directly into low-level control devices using expertise in experimental physics. Here we report on the design and implementation of an architecture capable of executing quantum network applications on quantum processors in platform-independent high-level software. We demonstrate the capability of the architecture to execute applications in high-level software by implementing it as a quantum network operating system—QNodeOS—and executing test programs, including a delegated computation from a client to a server on two quantum network nodes based on nitrogen-vacancy (NV) centres in diamond . We show how our architecture allows us to maximize the use of quantum network hardware by multitasking different applications. Our architecture can be used to execute programs on any quantum processor platform corresponding to our system model, which we illustrate by demonstrating an extra driver for QNodeOS for a trapped-ion quantum network node based on a single Ca atom . Our architecture lays the groundwork for computer science research in quantum network programming and paves the way for the development of software that can bring quantum network technology to society.

『摘要』 未来量子网络的目标是实现仅使用经典通信无法实现的新型互联网应用。迄今为止,量子网络应用和量子处理器功能的演示都是在特定于实验设置的专用软件中进行的,这些软件利用实验物理专业知识,直接将单一任务(应用实验)编程到低级控制设备中。本文报告了一种能够在平台无关的高级软件上于量子处理器上执行量子网络应用的架构的设计与实施情况。我们通过将该架构设计为量子网络操作系统——QNodeOS,并执行测试程序(包括基于金刚石中氮空位(NV)中心的两个量子网络节点上从客户端到服务器的委托计算),证明了该架构在高级软件中执行应用的能力。我们展示了该架构如何通过多任务处理不同的应用来最大限度地利用量子网络硬件。该架构可在符合我们系统模型的任何量子处理器平台上执行程序,我们通过为基于单个钙原子的囚禁离子量子网络节点演示QNodeOS的额外驱动程序来说明这一点。该架构为量子网络编程领域的计算机科学研究奠定了基础,并为开发能够将量子网络技术带给社会的软件铺平了道路。
『总结』 本研究设计了一种新架构,能在平台无关的高级软件上运行量子网络应用,展示了其在量子硬件多任务处理和跨平台执行程序方面的潜力,为量子网络编程研究和应用开发奠定了基础。
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『Abstract』Interfacial water exhibits rich and complex behaviour , playing an important part in chemistry, biology, geology and engineering. However, there is still much debate on the fundamental properties of water at hydrophobic interfaces, such as orientational ordering, the concentration of hydronium and hydroxide, improper hydrogen bonds and the presence of large electric fields . This controversy arises from the challenges in measuring interfacial systems, even with the most advanced experimental techniques and theoretical approaches available. Here we report on an in-solution, interface-selective Raman spectroscopy method using multivariate curve resolution to probe hexadecane-in-water emulsions, aided by a monomer-field theoretical model for Raman spectroscopy . Our results indicate that oil–water emulsion interfaces can exhibit reduced tetrahedral order and weaker hydrogen bonding, along with a substantial population of free hydroxyl groups that experience about 95 cm redshift in their stretching mode compared with planar oil–water interfaces. Given the known electrostatic zeta potential characteristic of oil droplets , we propose the existence of a strong electric field (about 50–90 MV cm ) emanating from the oil phase. This field is inferred indirectly but supported by control experiments and theoretical estimates. These observations are either absent or opposite in the molecular hydrophobic interface formed by small solutes or at planar oil–water interfaces. Instead, water structural disorder and enhanced electric fields emerge as unique features of the mesoscale interface in oil–water emulsions, potentially contributing to the accelerated chemical reactivity observed at hydrophobic–water interfaces .

『摘要』 界面水表现出丰富而复杂的行为,在化学、生物学、地质学和工程学等领域发挥着重要作用。然而,关于水在疏水界面处的基本特性,如取向有序性、水合氢离子和氢氧根离子的浓度、不适当的氢键以及强电场的存在,仍然存在诸多争议。这种争议源于界面系统测量的挑战性,即使采用最先进的实验技术和理论方法也难以解决。本文报告了一种溶液中的界面选择性拉曼光谱方法,该方法利用多元曲线分辨技术来探测十六烷-水乳状液,并辅以拉曼光谱的单体场理论模型。我们的结果表明,油-水乳液界面可以表现出降低的四面体有序性和较弱的氢键,以及大量的自由羟基。与平面油-水界面相比,这些自由羟基的拉伸模式发生了约95 cm⁻¹的红移。鉴于已知的油滴静电ζ电位特性,我们推测油相中存在一个强电场(约50–90 MV cm⁻¹)。这个电场是通过间接推断得出的,但得到了对照实验和理论估计的支持。这些现象在小溶质形成的分子疏水界面或平面油-水界面中要么不存在,要么表现相反。相反,水的结构无序和增强的电场成为油-水乳液中介观界面的独特特征,这可能有助于解释在疏水-水界面观察到的化学反应加速现象。
『总结』 本研究通过界面选择性拉曼光谱方法发现,油-水乳液界面具有降低的四面体有序性、较弱的氢键、大量自由羟基及强电场等独特特征,这些特征可能促进了疏水-水界面的化学反应加速。
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『Abstract』One of the main interpretations of deep-rooted geophysical structures in the mantle is that they stem from the top-down solidification of the primitive basal magma ocean of Earth above the core . However, it remains debated whether solids first formed at the bottom of the mantle, solidifying upward, or above the melts, solidifying downward. Here we show that gravitational segregation of dense, iron-rich melts from lighter, iron-poor solids drives mantle evolution, regardless of where melting curves and geotherms intersect. This process results in the accumulation of iron-oxide-rich melts above the core, forming a basal magma ocean. We numerically model mantle solidification using a new multiphase fluid dynamics approach that integrates melting phase relations and geochemical models. This enables estimating the compositional signature and spatial distribution of primordial geochemical reservoirs, which may be directly linked to the isotopic anomalies measured in Archean rocks . We find that a substantial amount of solids is produced at the surface of the planet, not at depth, injecting geochemical signatures of shallow silicate fractionation in the deep mantle. This work could serve as a foundation for re-examining the intricate interplay between mantle dynamics, petrology and geochemistry during the first thousand million years of the evolution of rocky planets.

『摘要』 地幔深处地球物理结构的主要解释之一是,它们源于地核上方原始基础岩浆洋的自上而下凝固。然而,固体是首先在地幔底部形成并向上凝固,还是在熔融物上方形成并向下凝固,这一点仍存在争议。本研究表明,无论熔化曲线和地热曲线在何处相交,富含铁的高密度熔体与缺铁的低密度固体之间的重力分离都会驱动地幔演化。这一过程导致富含氧化铁的熔体在地核上方聚集,形成一个基础岩浆洋。本研究采用了一种新的多相流体动力学方法,结合熔化相关系和地球化学模型,对地幔凝固过程进行了数值模拟。这使我们能够估算原始地球化学储层的成分特征和空间分布,这些储层可能与太古宙岩石中测得的同位素异常直接相关。我们发现,大量的固体是在行星表面而不是在深处产生的,这将浅层硅酸盐分异的地球化学特征注入了深部地幔。本研究可为重新审视岩石行星演化最初十亿年中地幔动力学、岩石学和地球化学之间的复杂相互作用奠定基础。
『总结』 研究表明地幔演化受富含铁熔体与缺铁固体间重力分离驱动,且大量固体在行星表面而非深处产生,为重新审视岩石行星早期演化中的地幔动力学等相互作用提供了基础。
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『Abstract』Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are persistent, bioaccumulative and anthropogenic pollutants that have attracted the attention of the public and private sectors because of their adverse impact on human health . Although various technologies have been deployed to degrade PFASs with a focus on non-polymeric functionalized compounds (perfluorooctanoic acid and perfluorooctanesulfonic acid) , a general PFAS destruction method coupled with fluorine recovery for upcycling is highly desirable. Here we disclose a protocol that converts multiple classes of PFAS, including the fluoroplastics polytetrafluoroethylene and polyvinylidene fluoride, into high-value fluorochemicals. To achieve this, PFASs were reacted with potassium phosphate salts under solvent-free mechanochemical conditions, a mineralization process enabling fluorine recovery as KF and K 2 PO 3 F for fluorination chemistry. The phosphate salts can be recovered for reuse, implying no detrimental impact on the phosphorus cycle. Therefore, PFASs are not only destructible but can now contribute to a sustainable circular fluorine economy.

『摘要』 全氟和多氟化合物(PFAS)是持久性、生物累积性且由人为产生的污染物,因其对人类健康的不利影响而引起了公共和私营部门的关注。尽管已部署各种技术来降解PFAS,重点关注非聚合功能化化合物(全氟辛酸和全氟辛烷磺酸),但亟需一种通用的PFAS销毁方法,同时结合氟回收以实现升级再利用。本文介绍了一种方案,可将多种类型的PFAS,包括氟塑料聚四氟乙烯和聚偏二氟乙烯,转化为高价值的氟化学品。为实现这一目的,在无溶剂的机械化学条件下使PFAS与磷酸钾盐反应,这一矿化过程能够回收氟,生成用于氟化化学的KF和K2PO3F。磷酸盐可回收再利用,这意味着对磷循环没有不利影响。因此,PFAS不仅可以被销毁,还能为可持续的循环氟经济做出贡献。
『总结』 本研究提出了一种新方案,通过机械化学反应将PFAS转化为高价值的氟化学品,并实现了氟和磷酸盐的回收再利用,为可持续的循环氟经济提供了可能。
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『Abstract』The generation of large-scale entangled states is crucial for quantum technologies, such as quantum computation , communication and metrology . Integrated quantum photonics that enables on-chip encoding, processing and detection of quantum light states offers a promising platform for the generation and manipulation of large-scale entangled states . Generating entanglement between qubits encoded in discrete variables within single photons is challenging, owing to the difficulty of making single photons interact on photonic chips . Devices that operate with continuous variables are more promising, as they enable the deterministic generation and entanglement of qumodes, in which information is encoded in light quadratures. Demonstrations so far have been limited to entanglement between two qumodes . Here we report the deterministic generation of a continuous-variable eight-mode entanglement on an integrated optical chip. The chip delivers a quantum microcomb that produces multimode squeezed-vacuum optical frequency combs below the threshold. We verify the inseparability of our eight-mode state and demonstrate supermode multipartite entanglement over hundreds of megahertz sideband frequencies through violation of the van Loock–Furusawa criteria. By measuring the full matrices of nullifier correlations with sufficiently low off-diagonal noises, we characterize multipartite entanglement structures, which are approximate to the expected cluster-type structures for finite squeezing. This work shows the potential of continuous-variable integrated photonic quantum devices for facilitating quantum computing, networking and sensing.

『摘要』 大规模纠缠态的生成对于量子计算、量子通信和量子测量等量子技术至关重要。集成量子光子学能够在芯片上对量子光态进行编码、处理和检测,为大规模纠缠态的生成和操控提供了一个有前景的平台。由于难以使单光子在光子芯片上发生相互作用,因此在单光子内部离散变量编码的量子比特之间生成纠缠是一项挑战。而操作连续变量的设备则更有前景,因为它们能够实现量子模的确定性生成和纠缠,其中信息被编码在光的正交分量中。迄今为止的演示仅限于两个量子模之间的纠缠。在此,我们报告了在集成光学芯片上确定性生成连续变量八模纠缠。该芯片提供了一个量子微梳,在阈值以下产生多模压缩真空光学频率梳。我们通过违反范洛克-富鲁萨瓦判据,验证了八模态的不可分离性,并证明了在数百兆赫兹的边带频率上实现了超模多体纠缠。通过测量具有足够低非对角噪声的零化子相关性的完整矩阵,我们表征了多体纠缠结构,这些结构与有限压缩下的预期簇型结构相近。本研究展示了连续变量集成光子量子器件在促进量子计算、量子网络和量子传感方面的潜力。
『总结』 本研究报告了在集成光学芯片上确定性生成连续变量八模纠缠的方法,验证了纠缠态的不可分离性,并展示了其在量子计算、网络和传感领域的应用潜力。
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『Abstract』Many technological breakthroughs in electronics and photonics were made possible by downscaling—the process of making elementary devices smaller in size . The downsizing of light-emitting diodes (LEDs) based on III–V semiconductors led to micro-LEDs , an ‘ultimate technology’ for displays. However, micro-LEDs are costly to produce and they exhibit severe efficiency losses when the pixel sizes are reduced to about 10 μm or less, hindering their potential in commercial applications. Here we show the downscaling of an emerging class of LEDs based on perovskite semiconductors to below the conventional size limits. Micro- and nano-perovskite LEDs (micro-PeLEDs/nano-PeLEDs) with characteristic pixel lengths from hundreds of micrometres down to about 90 nm are demonstrated, through a localized contact fabrication scheme that prevents non-radiative losses at the pixel boundaries. For our near-infrared (NIR) and green micro-PeLEDs, average external quantum efficiencies (EQEs) are maintained at around 20% across a wide range of pixel lengths (650 to 3.5 μm), exhibiting minimum performance reduction on downsizing. Our nano-PeLEDs with characteristic pixel lengths down to about 90 nm represent the smallest LEDs reported, enabling a record-high pixel density of 127,000 pixels per inch (PPI) among all classes of LED arrays. Our demonstration showcases the strength of micro- and nano-PeLEDs as a next-generation light-source technology with unprecedented compactness and scalability.

『摘要』 许多电子和光子学领域的技术突破都得益于缩小尺寸——即使基础器件的尺寸变得更小的过程。基于III-V族半导体的发光二极管(LED)的缩小促成了用于显示的“终极技术”micro-LED。然而,micro-LED生产成本高昂,且当像素尺寸减小到约10微米或更小时,效率会大幅下降,阻碍了其在商业应用中的潜力。本研究团队展示了将一类新兴的基于钙钛矿半导体的LED缩小到低于传统尺寸极限。通过一种局部接触制备方案(可防止像素边界处的非辐射损失),团队实现了特征像素长度从数百微米缩小到约90纳米的微纳米钙钛矿LED(micro-PeLED/nano-PeLED)。对于近红外(NIR)和绿色micro-PeLED,在较宽的像素长度范围(650至3.5微米)内,平均外量子效率(EQE)保持在20%左右,表现出缩小尺寸时性能降低最小化。团队研制的特征像素长度小至约90纳米的nano-PeLED是迄今报道的最小LED,在所有LED阵列中实现了创纪录的高像素密度,即每英寸127000像素(PPI)。本研究证明了微纳米钙钛矿LED作为下一代光源技术的优势,具有前所未有的紧凑性和可扩展性。
『总结』 研究团队成功将基于钙钛矿半导体的LED缩小到纳米级,并保持较高外量子效率,实现了LED领域的重大突破。
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『Abstract』Online platforms are rife with racial discrimination , but current interventions focus on employers rather than customers. We propose a customer-facing solution: changing to a two-point rating scale (dichotomization). Compared with the ubiquitous five-star scale, we argue that dichotomization reduces modern racial discrimination by focusing evaluators on the distinction between ‘good’ and ‘bad’ performance, thereby reducing how personal beliefs shape customer assessments. Study 1 is a quasi-natural experiment on a home-services labour platform ( n = 69,971) in which the company exogenously changed from a five-star scale to a dichotomous scale (thumbs up or thumbs down). Dichotomization eliminated customers’ racial discrimination whereby non-white workers received lower ratings and earned 91 cents for each US dollar paid to white workers for the same work. A pre-registered experiment (study 2, n = 652) found that the equalizing effect of dichotomization is most prevalent among evaluators holding modern racist beliefs. Further experiments (study 3, n = 1,435; study 4, n = 528) provide evidence of the proposed mechanism, and eight supplementary studies support measurement and design choices. Our research offers a promising intervention for reducing customers’ subtle racial discrimination in a large section of the economy and contributes to the interdisciplinary literature on evaluation processes and racial inequality.

『摘要』 网络平台上种族歧视现象屡见不鲜,但目前采取的干预措施主要针对雇主而非顾客。我们提出了一个面向顾客的解决方案:改用两点评级量表(即二分法)。与随处可见的五星量表相比,我们认为二分法能让评价者更关注“好”与“差”表现的区别,从而减少个人信念对顾客评价的影响,进而减轻现代种族歧视的现象。研究1是一项针对家政服务平台(n=69971)的准自然实验,该平台将评级方式从外源的五星量表改为二分量表(点赞或点踩)。采用二分法后,顾客的种族歧视现象消失了,非白人工作者所获得的评分不再偏低,并且每赚1美元,与白人工作者从事相同工作所获报酬的差距从91美分缩小至0。一项预先注册的实验(研究2,n=652)发现,二分法的平等化效应在持有现代种族主义信念的评价者中最为显著。进一步的实验(研究3,n=1435;研究4,n=528)为这一机制提供了证据,另外八项补充研究支持了测量和设计选择。我们的研究为减少经济中很大一部分领域里顾客的隐性种族歧视提供了一种颇有前景的干预措施,并丰富了有关评价流程和种族不平等的跨学科文献。
『总结』 研究发现,将评级量表改为二分法可以显著减少网络平台上顾客对非白人工作者的种族歧视现象。
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『Abstract』Greenlandic Inuit and other indigenous populations are underrepresented in genetic research , leading to inequity in healthcare opportunities. To address this, we performed analyses of sequenced or imputed genomes of 5,996 Greenlanders with extensive phenotypes. We quantified their historical population bottleneck and how it has shaped their genetic architecture to have fewer, but more common, variable sites. Consequently, we find twice as many high-impact genome-wide associations to metabolic traits in Greenland compared with Europe. We infer that the high-impact variants arose after the population split from Native Americans and thus are Arctic-specific, and show that some of them are common due to not only genetic drift but also selection. We also find that European-derived polygenic scores for metabolic traits are only half as accurate in Greenlanders as in Europeans, and that adding Arctic-specific variants improves the overall accuracy to the same level as in Europeans. Similarly, lack of representation in public genetic databases makes genetic clinical screening harder in Greenlandic Inuit, but inclusion of Greenlandic data remedies this by reducing the number of non-causal candidate variants by sixfold. Finally, we identify pronounced genetic fine structure that explains differences in prevalence of monogenic diseases in Greenland and, together with recent changes in mobility, leads to a predicted future reduction in risk for certain recessive diseases. These results illustrate how including data from Greenlanders can greatly reduce inequity in genomic-based healthcare.

『摘要』 格陵兰岛因纽特人和其他土著居民在遗传学研究中的代表性不足,导致医疗保健机会不平等。为解决这一问题,我们对5996名具有广泛表型的格陵兰人的测序或推断基因组进行了分析。我们量化了其历史上的人口瓶颈,以及这一瓶颈如何塑造了其遗传结构,使其变异位点更少,但更常见。因此,我们发现在格陵兰岛,与代谢特征相关的高影响力全基因组关联是欧洲的两倍。我们推断,这些高影响力变异是在格陵兰岛人口与美洲原住民分离后出现的,因此是北极特有的,并表明其中一些变异之所以常见,不仅是因为遗传漂变,还因为自然选择。我们还发现,欧洲衍生的代谢特征多基因评分在格陵兰人中的准确性只有欧洲人的一半,而加入北极特有变异后,总体准确性提高到了与欧洲人相同的水平。同样,公共遗传数据库中缺乏代表性使得格陵兰岛因纽特人的遗传临床筛查更加困难,但纳入格陵兰岛数据可通过将非因果候选变异体的数量减少六倍来弥补这一缺陷。最后,我们发现了显著的遗传精细结构,这解释了格陵兰岛单基因疾病流行率的差异,并且结合近期流动性的变化,预测未来某些隐性疾病的风险会降低。这些结果说明,纳入格陵兰岛人的数据可以大大减少基于基因组的医疗保健中的不平等现象。
『总结』 纳入格陵兰岛人的遗传数据可以减少医疗保健不平等,并提高遗传临床筛查和疾病风险预测的准确性。
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『Abstract』Duchenne muscular dystrophy (DMD) is a muscle-degenerating disease caused by mutations in the DMD gene, which encodes the dystrophin protein . Utrophin ( UTRN ), the genetic and functional paralogue of DMD , is upregulated in some DMD patients . To further investigate this UTRN upregulation, we first developed an inducible messenger RNA (mRNA) degradation system for DMD by introducing a premature termination codon (PTC) in one of its alternatively spliced exons. Inclusion of the PTC-containing exon triggers DMD mutant mRNA decay and UTRN upregulation. Notably, blocking nonsense-mediated mRNA decay results in the reversal of UTRN upregulation, whereas overexpressing DMD does not. Furthermore, overexpressing DMD minigenes in wild-type cells causes UTRN upregulation, as does a wild-type DMD minigene containing a self-cleaving ribozyme. To place these findings in a therapeutic context, we used splice-switching antisense oligonucleotides (ASOs) to induce the skipping of out-of-frame exons of DMD , aiming to introduce PTCs. We found that these ASOs cause UTRN upregulation. In addition, when using an ASO to restore the DMD reading frame in myotubes derived from a DMD patient, an actual DMD treatment, UTRN upregulation was reduced. Altogether, these results indicate that an mRNA decay-based mechanism called transcriptional adaptation plays a key role in UTRN upregulation in DMD patients, and they highlight an unexplored therapeutic application of ASOs, as well as ribozymes, in inducing genetic compensation via transcriptional adaptation.

『摘要』 Duchenne肌营养不良(DMD)是一种由DMD基因突变引起的肌肉退行性疾病,该基因负责编码抗肌萎缩蛋白。Utrophin(UTRN)是DMD的基因和功能同源物,在一些DMD患者中表达上调。为进一步研究这种UTRN上调现象,我们首先通过在DMD的一个可变剪接外显子中引入提前终止密码子(PTC),开发了一个可诱导的信使核糖核酸(mRNA)降解系统。包含含PTC的外显子会触发DMD突变mRNA的降解和UTRN的上调。值得注意的是,阻断无义介导的mRNA降解会导致UTRN上调的逆转,而过表达DMD则不会。此外,在野生型细胞中过表达DMD小基因会导致UTRN上调,含有自切割核酶的野生型DMD小基因也是如此。为将这些发现置于治疗背景中,我们使用了剪接转换反义寡核苷酸(ASO)来诱导DMD基因框架外外显子的跳跃,目的是引入PTC。我们发现,这些ASO会导致UTRN上调。此外,当使用ASO恢复来自DMD患者的肌管中的DMD阅读框时,即进行实际的DMD治疗时,UTRN上调减少。综上所述,这些结果表明,一种基于mRNA降解的机制,即转录适应,在DMD患者的UTRN上调中起关键作用,并且它们突显了ASO以及核酶在通过转录适应诱导基因补偿方面尚未开发的治疗应用。
『总结』 研究发现转录适应机制在DMD患者的UTRN上调中发挥关键作用,并揭示了ASO和核酶在通过转录适应诱导基因补偿方面的潜在治疗应用。
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『Abstract』Nucleotide-binding leucine-rich repeat (NLR) receptors play crucial roles in plant immunity by sensing pathogen effectors . In Arabidopsis , certain sensor NLRs function as NADases to catalyse the production of second messengers , which can be recognized by enhanced disease susceptibility 1 (EDS1) with its partner senescence-associated gene 101 (SAG101), to activate helper NLR N requirement gene 1 (NRG1) . A cryoelectron microscopy structure shows that second-messenger-activated EDS1–SAG101 mainly contacts the leucine-rich repeat domain of NRG1A to mediate the formation of an induced EDS1–SAG101–NRG1A complex. Structural comparisons show that binding of a second messenger induces conformational changes in EDS1–SAG101, which are recognized by NRG1A, leading to its allosteric activation. We further show that an inhibitory NRG1 family member, NRG1C, efficiently outcompetes NRG1A for binding to second-messenger-activated EDS1–SAG101. These findings uncover mechanisms for NRG1A activation through its recognition of a modified host EDS1–SAG101 complex, and NRG1A inhibition by NRG1C through sequestration of the activated EDS1–SAG101, thus shedding light on the activation and constraint of a central plant immune response system.

『摘要』 富含亮氨酸重复序列的核苷结合受体(NLR)在植物免疫中通过感知病原体效应因子发挥着关键作用。在拟南芥中,某些感应NLR作为NAD酶,催化第二信使的产生,这些第二信使可被增强疾病易感性1(EDS1)及其伴侣衰老相关基因101(SAG101)识别,以激活辅助NLR基因N需求基因1(NRG1)。冷冻电子显微镜结构显示,第二信使活化的EDS1-SAG101主要接触NRG1A的亮氨酸重复序列结构域,以介导诱导型EDS1-SAG101-NRG1A复合物的形成。结构比较表明,第二信使的结合会诱导EDS1-SAG101发生构象变化,这些变化被NRG1A识别,导致其发生变构激活。我们进一步证明,NRG1家族成员NRG1C能有效地与NRG1A竞争,结合第二信使活化的EDS1-SAG101。这些发现揭示了NRG1A通过识别修饰后的宿主EDS1-SAG101复合物而被激活的机制,以及NRG1C通过螯合活化的EDS1-SAG101来抑制NRG1A的机制,从而阐明了植物核心免疫反应系统的激活和约束机制。
『总结』 本研究揭示了植物中NLR受体NRG1A的激活机制及其被NRG1C抑制的机理,为理解植物免疫反应系统的激活和约束提供了新的见解。
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『Abstract』Plant nucleotide-binding leucine-rich repeat (NLR) receptors sense pathogen effectors and form resistosomes to confer immunity . Some sensor NLR resistosomes produce small molecules to induce formation of a heterotrimer complex with two lipase-like proteins, EDS1 and SAG101, and a helper NLR called NRG1 (refs. ). Activation of sensor NLR resistosomes also triggers NRG1 oligomerization and resistosome formation at the plasma membrane . We demonstrate that the Arabidopsis AtEDS1–AtSAG101–AtNRG1A heterotrimer formation is stabilized by the AtNRG1A loss-of-oligomerization mutant L134E . We report structures of AtEDS1–AtSAG101–AtNRG1A L134E and AtEDS1–AtSAG101–AtNRG1C heterotrimers with similar assembly mechanisms. AtNRG1A signalling is activated by the interaction with the AtEDS1–AtSAG101 heterodimer in complex with their small-molecule ligand. The truncated AtNRG1C maintains core interacting domains of AtNRG1A but develops further interactions with AtEDS1–AtSAG101 to outcompete AtNRG1A. Moreover, AtNRG1C lacks an N-terminal signalling domain and shows nucleocytoplasmic localization, facilitating its sequestration of AtEDS1–AtSAG101, which is also nucleocytoplasmic. Our study shows the activation and inhibition mechanisms of a plant helper NLR.

『摘要』 植物的核苷酸结合富含亮氨酸重复序列(NLR)受体能够感知病原体效应物并形成抗病小体以赋予免疫。一些感知NLR抗病小体会产生小分子,诱导其与两种脂酶样蛋白EDS1和SAG101以及一种名为NRG1的辅助NLR形成异三聚体复合物。感知NLR抗病小体的激活还会触发NRG1在质膜上的寡聚化和抗病小体的形成。我们证明,拟南芥AtEDS1–AtSAG101–AtNRG1A异三聚体的形成被AtNRG1A的寡聚化缺失突变体L134E所稳定。我们报告了具有相似组装机制的AtEDS1–AtSAG101–AtNRG1A L134E和AtEDS1–AtSAG101–AtNRG1C异三聚体的结构。AtNRG1A信号通过与结合其小分子配体的AtEDS1–AtSAG101异二聚体相互作用而被激活。截短的AtNRG1C保留了AtNRG1A的核心相互作用结构域,但与AtEDS1–AtSAG101发展出进一步的相互作用,从而在与AtNRG1A的竞争中胜出。此外,AtNRG1C缺乏N端信号结构域,并显示出核质定位,从而促进其对同样具有核质定位的AtEDS1–AtSAG101的螯合。我们的研究揭示了植物辅助NLR的激活和抑制机制。
『总结』 本研究揭示了植物中辅助NLR的激活和抑制机制,涉及异三聚体的形成、NRG1的寡聚化及与EDS1-SAG101的相互作用。
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『Abstract』The recognition of ligands by transmembrane proteins is essential for the exchange of materials, energy and information across biological membranes. Progress has been made in the de novo design of transmembrane proteins , as well as in designing water-soluble proteins to bind small molecules , but de novo design of transmembrane proteins that tightly and specifically bind to small molecules remains an outstanding challenge . Here we present the accurate design of ligand-binding transmembrane proteins by integrating deep learning and energy-based methods. We designed pre-organized ligand-binding pockets in high-quality four-helix backbones for a fluorogenic ligand, and generated a transmembrane span using gradient-guided hallucination. The designer transmembrane proteins specifically activated fluorescence of the target fluorophore with mid-nanomolar affinity, exhibiting higher brightness and quantum yield compared to those of enhanced green fluorescent protein. These proteins were highly active in the membrane fraction of live bacterial and eukaryotic cells following expression. The crystal and cryogenic electron microscopy structures of the designer protein–ligand complexes were very close to the structures of the design models. We showed that the interactions between ligands and transmembrane proteins within the membrane can be accurately designed. Our work paves the way for the creation of new functional transmembrane proteins, with a wide range of applications including imaging, ligand sensing and membrane transport.

『摘要』 跨膜蛋白对配体的识别对于生物膜上物质、能量和信息的交换至关重要。在跨膜蛋白的从头设计以及水溶性蛋白与小分子结合的设计方面已取得一些进展,但从头设计出能与小分子紧密且特异性结合的跨膜蛋白仍是一项艰巨的挑战。本文通过将深度学习方法与基于能量的方法相结合,实现了对配体结合型跨膜蛋白的精准设计。我们为荧光配体设计了预先组织的配体结合口袋,这些口袋位于高质量的四螺旋主链中,并使用梯度引导生成法构建了一个跨膜区段。所设计的跨膜蛋白能特异性地激活靶标荧光团的荧光,亲和力达到纳摩尔级别,与增强型绿色荧光蛋白相比,表现出更高的亮度和量子产率。这些蛋白在表达后,于活菌和真核细胞的膜组分中均表现出高活性。设计者蛋白-配体复合物的晶体结构和冷冻电子显微镜结构与设计模型的结构非常接近。本文证明了膜内配体与跨膜蛋白之间的相互作用是可以被精准设计的。我们的工作为创建具有成像、配体传感和膜转运等多种应用前景的新型功能性跨膜蛋白奠定了基础。
『总结』 本研究结合深度学习和能量方法,成功设计出能特异性结合小分子的跨膜蛋白,为开发新型功能性跨膜蛋白提供了新途径。
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『Abstract』Human treponemal infections are caused by a family of closely related Treponema pallidum that give rise to the diseases yaws, bejel, pinta and, most notably, syphilis . Debates on a common origin for these pathogens and the history of syphilis itself have weighed evidence for the ‘Columbian hypothesis’ , which argues for an American origin, against that for the ‘pre-Columbian hypothesis’ , which argues for the presence of the disease in Eurasia in the Medieval period and possibly earlier. Although molecular data has provided a genetic basis for distinction of the typed subspecies , deep evolution of the complex has remained unresolved owing to limitations in the conclusions that can be drawn from the sparse palaeogenomic data that are currently available. Here we explore this evolutionary history through analyses of five pre- and peri-contact ancient treponemal genomes from the Americas that represent ancient relatives of the T. pallidum subsp. pallidum (syphilis), T. pallidum subsp. pertenue (yaws) and T. pallidum subsp. endemicum (bejel) lineages. Our data indicate unexplored diversity and an emergence of T. pallidum that post-dates human occupation in the Americas. Together, these results support an American origin for all T. pallidum characterized at the genomic level, both modern and ancient.

『摘要』 人类密螺旋体感染是由一组密切相关的密螺旋体引起的,这些密螺旋体会导致雅司病、贝杰尔病、品他病,以及最著名的梅毒。关于这些病原体的共同起源以及梅毒本身的历史,人们一直在就“哥伦布假说”(认为起源于美洲)和“前哥伦布假说”(认为该疾病在中世纪甚至更早时期就已存在于欧亚大陆)争论不休。尽管分子数据为区分不同类型的亚种提供了遗传基础,但由于目前可用的古基因组数据稀少,所得结论具有局限性,因此该菌群的深层进化问题仍悬而未决。在本文中,我们通过分析来自美洲的五个接触前和接触时期的古代密螺旋体基因组(分别代表梅毒(T. pallidum subsp. pallidum)、雅司病(T. pallidum subsp. pertenue)和贝杰尔病(T. pallidum subsp. endemicum)谱系的古老亲缘关系)来探索其进化史。我们的数据表明,密螺旋体具有未被发现的多样性,并且其出现时间晚于人类定居美洲的时间。总的来说,这些结果在基因组层面上支持了所有现代和古代密螺旋体均起源于美洲的观点。
『总结』 通过分析古代密螺旋体基因组,研究发现密螺旋体具有多样性,且支持所有密螺旋体(包括现代和古代)均起源于美洲的观点。
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『Abstract』Personalized cancer vaccines (PCVs) can generate circulating immune responses against predicted neoantigens . However, whether such responses can target cancer driver mutations, lead to immune recognition of a patient’s tumour and result in clinical activity are largely unknown. These questions are of particular interest for patients who have tumours with a low mutational burden. Here we conducted a phase I trial (ClinicalTrials.gov identifier NCT02950766) to test a neoantigen-targeting PCV in patients with high-risk, fully resected clear cell renal cell carcinoma (RCC; stage III or IV) with or without ipilimumab administered adjacent to the vaccine. At a median follow-up of 40.2 months after surgery, none of the 9 participants enrolled in the study had a recurrence of RCC. No dose-limiting toxicities were observed. All patients generated T cell immune responses against the PCV antigens, including to RCC driver mutations in VHL , PBRM1 , BAP1 , KDM5C and PIK3CA . Following vaccination, there was a durable expansion of peripheral T cell clones. Moreover, T cell reactivity against autologous tumours was detected in seven out of nine patients. Our results demonstrate that neoantigen-targeting PCVs in high-risk RCC are highly immunogenic, capable of targeting key driver mutations and can induce antitumour immunity. These observations, in conjunction with the absence of recurrence in all nine vaccinated patients, highlights the promise of PCVs as effective adjuvant therapy in RCC.

『摘要』 个性化癌症疫苗(PCV)可以产生针对预测的新抗原的循环免疫反应。然而,这些反应是否能够靶向癌症驱动突变,导致患者肿瘤被免疫识别并产生临床疗效,在很大程度上仍是未知的。这些问题对于肿瘤突变负荷较低的患者而言尤其值得关注。本研究开展了一项I期试验(ClinicalTrials.gov标识符:NCT02950766),以测试一种针对新抗原的PCV在伴或不伴疫苗附近注射伊匹木单抗的高危、完全切除的透明细胞肾细胞癌(RCC;III期或IV期)患者中的效果。在术后中位随访时间40.2个月时,入组的9例患者中无一例RCC复发。未观察到剂量限制性毒性。所有患者均产生了针对PCV抗原的T细胞免疫反应,包括针对VHL、PBRM1、BAP1、KDM5C和PIK3CA中的RCC驱动突变。接种疫苗后,外周T细胞克隆持续扩增。此外,在9例患者中有7例检测到针对自体肿瘤的T细胞反应性。本研究结果表明,在高危RCC中,针对新抗原的PCV具有很强的免疫原性,能够靶向关键驱动突变,并诱导抗肿瘤免疫。这些观察结果,加上所有9例接种疫苗的患者均未复发的现象,凸显了PCV作为RCC有效辅助治疗的潜力。
『总结』 针对新抗原的个性化癌症疫苗在高危肾细胞癌患者中显示出强免疫原性,能有效靶向关键驱动突变并诱导抗肿瘤免疫,且所有接种疫苗的患者均未复发。
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『Abstract』The genetic code is conserved across all domains of life, yet exceptions have revealed variations in codon assignments and associated translation factors . Inspired by this natural malleability, synthetic approaches have demonstrated whole-genome replacement of synonymous codons to construct genomically recoded organisms (GROs) with alternative genetic codes. However, no efforts have fully leveraged translation factor plasticity and codon degeneracy to compress translation function to a single codon and assess the possibility of a non-degenerate code. Here we describe construction and characterization of Ochre, a GRO that fully compresses a translational function into a single codon. We replaced 1,195 TGA stop codons with the synonymous TAA in ∆TAG Escherichia coli C321.∆A . We then engineered release factor 2 (RF2) and tRNA to mitigate native UGA recognition, translationally isolating four codons for non-degenerate functions. Ochre thus utilizes UAA as the sole stop codon, with UGG encoding tryptophan and UAG and UGA reassigned for multi-site incorporation of two distinct non-standard amino acids into single proteins with more than 99% accuracy. Ochre fully compresses degenerate stop codons into a single codon and represents an important step toward a 64-codon non-degenerate code that will enable precise production of multi-functional synthetic proteins with unnatural encoded chemistries and broad utility in biotechnology and biotherapeutics.

『摘要』 遗传密码在所有生命领域都是保守的,然而例外情况显示出密码子分配和相关翻译因子存在差异。受这种天然可变性的启发,合成方法已证明可通过全基因组同义密码子替换来构建具有替代遗传密码的基因组重编码生物体(GRO)。然而,目前尚未有研究充分利用翻译因子可塑性和密码子简并性将翻译功能压缩到单个密码子,并评估非简并密码子的可能性。本文介绍了Ochre的构建和特征,这是一种将翻译功能完全压缩到单个密码子的GRO。我们在∆TAG大肠杆菌C321.∆A中,将1195个TGA终止密码子替换为同义的TAA。然后,我们对释放因子2(RF2)和tRNA进行工程改造,以减轻对原生UGA的识别,从而在翻译水平上隔离了四个密码子以用于非简并功能。因此,Ochre使用UAA作为唯一的终止密码子,UGG编码色氨酸,而UAG和UGA则被重新分配,用于以超过99%的准确率在单个蛋白质中多位点掺入两种不同的非标准氨基酸。Ochre将简并的终止密码子完全压缩为一个密码子,这是迈向64个密码子的非简并密码子的重要一步,将使能够精确生产具有非天然编码化学性质的多功能合成蛋白质,在生物技术和生物治疗药物领域具有广泛应用前景。
『总结』 本研究构建了一种将翻译功能完全压缩到单个密码子的基因组重编码生物体Ochre,为实现64个密码子的非简并密码子迈出了重要一步。
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『Abstract』Tissue-resident memory CD8 T (T RM ) cells provide protection from infection at barrier sites. In the small intestine, T RM cells are found in at least two distinct subpopulations: one with higher expression of effector molecules and another with greater memory potential . However, the origins of this diversity remain unknown. Here we proposed that distinct tissue niches drive the phenotypic heterogeneity of T RM cells. To test this, we leveraged spatial transcriptomics of human samples, a mouse model of acute systemic viral infection and a newly established strategy for pooled optically encoded gene perturbations to profile the locations, interactions and transcriptomes of pathogen-specific T RM cell differentiation at single-transcript resolution. We developed computational approaches to capture cellular locations along three anatomical axes of the small intestine and to visualize the spatiotemporal distribution of cell types and gene expression. Our study reveals that the regionalized signalling of the intestinal architecture supports two distinct T RM cell states: differentiated T RM cells and progenitor-like T RM cells, located in the upper villus and lower villus, respectively. This diversity is mediated by distinct ligand–receptor activities, cytokine gradients and specialized cellular contacts. Blocking TGFβ or CXCL9 and CXCL10 sensing by antigen-specific CD8 T cells revealed a model consistent with anatomically delineated, early fate specification. Ultimately, our framework for the study of tissue immune networks reveals that T cell location and functional state are fundamentally intertwined.

『摘要』 组织驻留记忆CD8 T(T RM)细胞可在屏障部位提供抗感染保护。在小肠中,T RM细胞至少存在两种不同的亚群:一种表达较高的效应分子,另一种具有更强的记忆潜力。然而,这种多样性的起源尚不清楚。本研究提出,不同的组织微环境驱动了T RM细胞的表型异质性。为了验证这一点,本研究利用人类样本的空间转录组学、急性全身性病毒感染小鼠模型和一种新建的用于汇集光学编码基因扰动的方法,以单转录本分辨率描绘了病原体特异性T RM细胞分化的位置、相互作用和转录组。本研究开发了计算方法,用于捕获小肠三个解剖轴上的细胞位置,并可视化细胞类型和基因表达的时空分布。研究结果显示,肠道结构的区域化信号支持两种不同的T RM细胞状态:分化的T RM细胞和祖细胞样T RM细胞,分别位于绒毛上部和绒毛下部。这种多样性由不同的配体-受体活性、细胞因子梯度和特定的细胞接触介导。阻断抗原特异性CD8 T细胞对TGFβ或CXCL9和CXCL10的感应,所揭示的模型与解剖学上界定的早期命运决定一致。最终,本研究建立的组织免疫网络研究框架表明,T细胞的位置和功能状态是密切相关的。
『总结』 本研究表明组织微环境的差异驱动了小肠T RM细胞的表型异质性,且T细胞的位置和功能状态密切相关。
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『Abstract』Cardiomyocytes can be implanted to remuscularize the failing heart . Challenges include sufficient cardiomyocyte retention for a sustainable therapeutic impact without intolerable side effects, such as arrhythmia and tumour growth. We investigated the hypothesis that epicardial engineered heart muscle (EHM) allografts from induced pluripotent stem cell-derived cardiomyocytes and stromal cells structurally and functionally remuscularize the chronically failing heart without limiting side effects in rhesus macaques. After confirmation of in vitro and in vivo (nude rat model) equivalence of the newly developed rhesus macaque EHM model with a previously established Good Manufacturing Practice-compatible human EHM formulation , long-term retention (up to 6 months) and dose-dependent enhancement of the target heart wall by EHM grafts constructed from 40 to 200 million cardiomyocytes/stromal cells were demonstrated in macaques with and without myocardial infarction-induced heart failure. In the heart failure model, evidence for EHM allograft-enhanced target heart wall contractility and ejection fraction, which are measures for local and global heart support, was obtained. Histopathological and gadolinium-based perfusion magnetic resonance imaging analyses confirmed cell retention and functional vascularization. Arrhythmia and tumour growth were not observed. The obtained feasibility, safety and efficacy data provided the pivotal underpinnings for the approval of a first-in-human clinical trial on tissue-engineered heart repair. Our clinical data confirmed remuscularization by EHM implantation in a patient with advanced heart failure.

『摘要』 心肌细胞可被移植以使衰竭的心脏重新肌肉化。其挑战在于确保心肌细胞能够足量存活以持续发挥治疗效果,同时不会引起心律失常和肿瘤生长等无法耐受的副作用。本研究探讨了这样一个假设:由诱导多能干细胞衍生的心肌细胞和基质细胞构成的心外膜工程化心脏肌肉(EHM)同种异体移植物可在结构上和功能上使恒河猴慢性衰竭的心脏重新肌肉化,且不会引发限制性副作用。在确认新开发的恒河猴EHM模型与既往建立的符合良好生产规范的人类EHM制剂在体内(裸鼠模型)和体外具有等效性后,本研究在有无心肌梗死所致心衰的恒河猴中证明了由4000万至2亿个心肌细胞/基质细胞构建的EHM移植物可实现长期留存(最长6个月),并且可呈剂量依赖性地增强目标心壁。在心衰模型中,已获得EHM同种异体移植物增强目标心壁收缩力和射血分数的证据,而这两项指标分别是对局部和整体心脏支持的评估指标。组织病理学和钆基灌注磁共振成像分析证实了细胞的留存和功能性血管化。未观察到心律失常和肿瘤生长。本研究所获可行性、安全性和有效性数据为批准首项组织工程化心脏修复的临床试验奠定了关键基础。本研究的临床数据证实,EHM移植可使一名晚期心力衰竭患者的心脏重新肌肉化。
『总结』 研究表明心外膜工程化心脏肌肉同种异体移植物可使衰竭心脏重新肌肉化,且未观察到严重副作用,该研究数据支持了开展首项人体临床试验。
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『Abstract』Numerous studies support the role of dopamine in modulating aggression , but the exact neural mechanisms remain elusive. Here we show that dopaminergic cells in the ventral tegmental area (VTA) can bidirectionally modulate aggression in male mice in an experience-dependent manner. Although VTA dopaminergic cells strongly influence aggression in novice aggressors, they become ineffective in expert aggressors. Furthermore, eliminating dopamine synthesis in the VTA prevents the emergence of aggression in naive mice but leaves aggression intact in expert aggressors. VTA dopamine modulates aggression through the dorsal lateral septum (dLS), a region known for aggression control. Dopamine enables the flow of information from the hippocampus to the dLS by weakening local inhibition in novice aggressors. In expert aggressors, dLS local inhibition naturally weakens, and the ability of dopamine to modulate dLS cells diminishes. Overall, these results reveal a sophisticated role of dopamine in the rise of aggression in adult male mice.

『摘要』 多项研究支持多巴胺在调节攻击行为中的作用,但其确切的神经机制仍不清楚。本研究发现,腹侧被盖区(VTA)的多巴胺能细胞可以以一种经验依赖的方式双向调节雄性小鼠的攻击行为。虽然VTA多巴胺能细胞对新手攻击者的攻击行为有强烈影响,但在熟练攻击者中却无效。此外,消除VTA中的多巴胺合成会阻止幼鼠产生攻击行为,但不会影响熟练攻击者的攻击行为。VTA多巴胺通过背外侧隔(dLS)——一个已知的控制攻击行为的区域来调节攻击行为。多巴胺通过减弱新手攻击者中的局部抑制,使信息能够从海马体流向dLS。在熟练攻击者中,dLS的局部抑制自然减弱,多巴胺调节dLS细胞的能力也会降低。总的来说,这些研究结果揭示了多巴胺在成年雄性小鼠攻击行为产生中的复杂作用。
『总结』 研究发现VTA多巴胺能细胞能经验依赖地双向调节雄性小鼠攻击行为,且其作用机制涉及dLS区域及海马体到dLS的信息流动。
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『Abstract』Molecular recognition events between proteins drive biological processes in living systems . However, higher levels of mechanistic regulation have emerged, in which protein–protein interactions are conditioned to small molecules . Despite recent advances, computational tools for the design of new chemically induced protein interactions have remained a challenging task for the field . Here we present a computational strategy for the design of proteins that target neosurfaces, that is, surfaces arising from protein–ligand complexes. To develop this strategy, we leveraged a geometric deep learning approach based on learned molecular surface representations and experimentally validated binders against three drug-bound protein complexes: Bcl2–venetoclax, DB3–progesterone and PDF1–actinonin. All binders demonstrated high affinities and accurate specificities, as assessed by mutational and structural characterization. Remarkably, surface fingerprints previously trained only on proteins could be applied to neosurfaces induced by interactions with small molecules, providing a powerful demonstration of generalizability that is uncommon in other deep learning approaches. We anticipate that such designed chemically induced protein interactions will have the potential to expand the sensing repertoire and the assembly of new synthetic pathways in engineered cells for innovative drug-controlled cell-based therapies .

『摘要』 生物体内的生物过程由蛋白质之间的分子识别事件驱动。然而,更高级别的机制调控已经出现,在这种调控中,蛋白质-蛋白质相互作用受到小分子的制约。尽管近期已取得一些进展,但对于该领域而言,设计新型化学诱导蛋白质相互作用的计算工具仍然是一项具有挑战性的任务。本文提出了一种针对新表面(即由蛋白质-配体复合物产生的表面)靶向蛋白的设计计算策略。为开发这一策略,本文利用了一种基于学习分子表面表征的几何深度学习方法,并针对三种药物结合蛋白复合物(Bcl2–venetoclax、DB3–progesterone和PDF1–actinonin)对结合剂进行了实验验证。通过突变和结构表征评估,所有结合剂均表现出高亲和力和精确特异性。值得注意的是,先前仅在蛋白质上训练的表面指纹可以应用于小分子相互作用产生的新表面,这有力地证明了该方法的通用性,而这种通用性在其他深度学习方法中并不常见。本文预计,此类设计的化学诱导蛋白质相互作用将有可能扩展工程细胞的感应范围,并组装新的合成途径,用于创新的药物控制细胞疗法。
『总结』 本研究提出了一种新的计算策略,利用几何深度学习设计能靶向蛋白质-配体复合物产生的新表面的蛋白质,该策略在药物控制细胞疗法中具有广阔的应用前景。
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『Abstract』The ability to flexibly switch our responses to external stimuli according to contextual information is critical for successful interactions with a complex world. Context-dependent computations are necessary across many domains , yet their neural implementations remain poorly understood. Here we developed a novel behavioural task in rats to study context-dependent selection and accumulation of evidence for decision-making . Under assumptions supported by both monkey and rat data, we first show mathematically that this computation can be supported by three dynamical solutions and that all networks performing the task implement a combination of these solutions. These solutions can be identified and tested directly with experimental data. We further show that existing electrophysiological and modelling data are compatible with the full variety of possible combinations of these solutions, suggesting that different individuals could use different combinations. To study variability across individual subjects, we developed automated, high-throughput methods to train rats on our task and trained many subjects using these methods. Consistent with theoretical predictions, neural and behavioural analyses revealed substantial heterogeneity across rats, despite uniformly good task performance. Our theory further predicts a specific link between behavioural and neural signatures, which was robustly supported in the data. In summary, our results provide an experimentally supported theoretical framework to analyse individual variability in biological and artificial systems that perform flexible decision-making tasks, open the door to cellular-resolution studies of individual variability in higher cognition, and provide insights into neural mechanisms of context-dependent computation more generally.

『摘要』 根据上下文信息灵活调整我们对外部刺激的反应对于成功与复杂世界互动至关重要。尽管跨领域都需要依赖上下文的计算,但其神经机制仍知之甚少。本研究开发了一种新的大鼠行为任务,用于研究决策过程中依赖于上下文的证据选择和累积。本研究在猴和大鼠的数据都支持的假设下,首先通过数学方法证明了这种计算可以由三种动力学解决方案支持,并且执行该任务的所有网络都实现了这些解决方案的组合。这些解决方案可以直接通过实验数据进行识别和测试。研究还表明,现有的电生理和建模数据与这些解决方案各种可能组合的兼容性,这意味着不同的个体可能使用不同的组合。为了研究不同个体之间的差异,本研究开发了自动化、高通量的方法来训练大鼠执行任务,并使用这些方法训练了许多大鼠。与理论预测一致,神经和行为分析显示大鼠之间存在显著差异,尽管它们的任务表现都一致良好。本研究理论还预测了行为特征和神经特征之间的特定联系,这一预测在数据中得到有力支持。
『总结』 研究结果为分析执行灵活决策任务的生物和人工系统中的个体差异提供了一个实验支持的理论框架,为从细胞分辨率角度研究高级认知中的个体差异打开了大门,并更广泛地揭示了依赖上下文的计算的神经机制。
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『Abstract』The human genome contains millions of candidate cis -regulatory elements (cCREs) with cell-type-specific activities that shape both health and many disease states . However, we lack a functional understanding of the sequence features that control the activity and cell-type-specific features of these cCREs. Here we used lentivirus-based massively parallel reporter assays (lentiMPRAs) to test the regulatory activity of more than 680,000 sequences, representing an extensive set of annotated cCREs among three cell types (HepG2, K562 and WTC11), and found that 41.7% of these sequences were active. By testing sequences in both orientations, we find promoters to have strand-orientation biases and their 200-nucleotide cores to function as non-cell-type-specific ‘on switches’ that provide similar expression levels to their associated gene. By contrast, enhancers have weaker orientation biases, but increased tissue-specific characteristics. Utilizing our lentiMPRA data, we develop sequence-based models to predict cCRE function and variant effects with high accuracy, delineate regulatory motifs and model their combinatorial effects. Testing a lentiMPRA library encompassing 60,000 cCREs in all three cell types further identified factors that determine cell-type specificity. Collectively, our work provides an extensive catalogue of functional CREs in three widely used cell lines and showcases how large-scale functional measurements can be used to dissect regulatory grammar.

『摘要』 人类基因组包含数百万个具有细胞类型特异性活性的候选顺式调控元件(cCRE),这些元件决定着健康状态和许多疾病状态。然而,我们对于这些cCRE控制活性和细胞类型特异性特征的序列特征尚缺乏功能性理解。在这里,我们使用基于慢病毒的大规模并行报告基因分析(lentiMPRA)来测试超过68万个序列的调控活性,这些序列代表了三种细胞类型(HepG2、K562和WTC11)中一组广泛的注释cCRE,并发现其中41.7%的序列具有活性。通过测试双向序列,我们发现启动子具有链方向偏好性,其200个核苷酸核心作为非细胞类型特异性的“开启开关”,为其相关基因提供相似的表达水平。相比之下,增强子具有较弱的方向偏好性,但具有更强的组织特异性。利用我们的lentiMPRA数据,我们开发了基于序列的模型,可以高精度预测cCRE功能和变异效应,描绘调控基序并模拟其组合效应。在三种细胞类型中测试包含6万个cCRE的lentiMPRA文库,进一步确定了决定细胞类型特异性的因素。总的来说,我们的工作为三种广泛使用的细胞系提供了大量的功能性CRE目录,并展示了如何利用大规模功能性测量来剖析调控规律。
『总结』 本研究通过大规模实验和模型开发,揭示了人类基因组中大量cCRE的功能特性和细胞类型特异性,为理解基因调控机制提供了宝贵资源。
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『Abstract』Peripheral neuropathy is a common complication of type 2 diabetes, which is strongly associated with obesity , causing sensory loss and, in some patients, neuropathic pain . Although the onset and progression of diabetic peripheral neuropathy is linked with dyslipidaemia and hyperglycaemia , the contribution of inflammation to peripheral neuropathy pathogenesis has not been investigated. Here we used a high-fat, high-fructose diet (HFHFD), which induces obesity and prediabetic metabolic changes, to study the onset of peripheral neuropathy. Mice fed the HFHFD developed persistent heat hypoalgesia after 3 months, but a reduction in epidermal skin nerve fibre density manifested only at 6 months. Using single-cell sequencing, we found that CCR2 macrophages infiltrate the sciatic nerves of HFHFD-fed mice well before axonal degeneration is detectable. These infiltrating macrophages share gene expression similarities with nerve-crush-induced macrophages and express neurodegeneration-associated microglial marker genes , although there is no axon loss or demyelination. Inhibiting the macrophage recruitment by genetically or pharmacologically blocking CCR2 signalling resulted in more severe heat hypoalgesia and accelerated skin denervation, as did deletion of Lgals3 , a gene expressed in recruited macrophages. Recruitment of macrophages into the peripheral nerves of obese prediabetic mice is, therefore, neuroprotective, delaying terminal sensory axon degeneration by means of galectin 3. Potentiating and sustaining early neuroprotective immune responses in patients could slow or prevent peripheral neuropathy.

『摘要』 周围神经病变是2型糖尿病的常见并发症,与肥胖密切相关,会导致感觉丧失,部分患者还会出现神经病理性疼痛。尽管糖尿病周围神经病变的发生和发展与血脂异常和高血糖有关,但炎症对周围神经病变发病机制的作用尚未明确。本研究使用了可诱导肥胖和糖尿病前期代谢变化的高脂高果糖饮食(HFHFD),来研究周围神经病变的发生。喂食HFHFD的小鼠在3个月后出现持续性热痛觉减退,但表皮皮肤神经纤维密度减少仅在6个月时才出现。通过单细胞测序,研究人员发现,在可检测到轴突变性之前,CCR2巨噬细胞就已浸润到喂食HFHFD的小鼠坐骨神经中。这些浸润的巨噬细胞与神经压榨损伤诱导的巨噬细胞在基因表达上具有相似性,并表达与神经退行性变相关的微胶质细胞标志基因,尽管此时并没有出现轴突丢失或脱髓鞘。通过基因或药物手段阻断CCR2信号传导来抑制巨噬细胞的募集,或通过删除在募集的巨噬细胞中表达的Lgals3基因,都会导致热痛觉减退更加严重,皮肤去神经支配加速。因此,肥胖的糖尿病前期小鼠周围神经中巨噬细胞的募集具有神经保护作用,可通过半乳糖凝集素3延缓末端感觉轴突的退行性变。增强和维持患者早期的神经保护性免疫反应可以减缓或预防周围神经病变。
『总结』 研究发现,肥胖的糖尿病前期小鼠周围神经中CCR2巨噬细胞的募集具有神经保护作用,这一发现为通过增强早期神经保护性免疫反应来减缓或预防周围神经病变提供了新思路。
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『Abstract』Nanoribbons, nanometre-wide strips of a two-dimensional material, are a unique system in condensed matter. They combine the exotic electronic structures of low-dimensional materials with an enhanced number of exposed edges, where phenomena including ultralong spin coherence times , quantum confinement and topologically protected states can emerge. An exciting prospect for this material concept is the potential for both a tunable semiconducting electronic structure and magnetism along the nanoribbon edge, a key property for spin-based electronics such as (low-energy) non-volatile transistors . Here we report the magnetic and semiconducting properties of phosphorene nanoribbons (PNRs). We demonstrate that at room temperature, films of PNRs show macroscopic magnetic properties arising from their edge, with internal fields of roughly 240 to 850 mT. In solution, a giant magnetic anisotropy enables the alignment of PNRs at sub-1-T fields. By leveraging this alignment effect, we discover that on photoexcitation, energy is rapidly funnelled to a state that is localized to the magnetic edge and coupled to a symmetry-forbidden edge phonon mode. Our results establish PNRs as a fascinating system for studying the interplay between magnetism and semiconducting ground states at room temperature and provide a stepping-stone towards using low-dimensional nanomaterials in quantum electronics.

『摘要』 纳米带是二维材料制成的纳米级宽的条带,是凝聚态物质中的一种独特体系。它们将低维材料的奇异电子结构与数量增加的裸露边缘相结合,可出现超长自旋相干时间、量子限制和拓扑保护态等现象。这种材料概念有一个激动人心的前景,即纳米带边缘有可能同时具备可调半导体电子结构和磁性,这是自旋电子器件(如(低能耗)非易失性晶体管)的关键特性。在此,我们报告了磷烯纳米带(PNRs)的磁性和半导体特性。我们证明,在室温下,磷烯纳米带薄膜因其边缘而表现出宏观磁性,内部场强约为240至850毫特斯拉。在溶液中,巨大的磁各向异性使磷烯纳米带能够在小于1特斯拉的磁场中对齐。利用这种对齐效应,我们发现,在光激发时,能量会迅速聚集到一种局限于磁性边缘的状态,并与一种对称禁戒的边缘声子模式相耦合。我们的研究结果证明,磷烯纳米带是研究室温下磁性与半导体基态之间相互作用的一个迷人体系,并为在低维纳米材料应用于量子电子学领域奠定了基础。
『总结』 研究表明磷烯纳米带在室温下表现出宏观磁性和半导体特性,其能量可迅速聚集于磁性边缘,为量子电子学应用提供了新基础。
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『Abstract』The biogenic structures produced by termites, ants and earthworms provide key functions across global ecosystems . However, little is known about the drivers of the soil engineering effects caused by these small but important invertebrates at the global scale. Here we show, on the basis of a meta-analysis of 12,975 observations from 1,047 studies on six continents, that all three taxa increase soil macronutrient content, soil respiration and soil microbial and plant biomass compared with reference soils. The effect of termites on soil respiration and plant biomass, and the effect of earthworms on soil nitrogen and phosphorus content, increase with mean annual temperature and peak in the tropics. By contrast, the effects of ants on soil nitrogen, soil phosphorus, plant biomass and survival rate peak at mid-latitude ecosystems that have the lowest primary productivity. Notably, termites and ants increase plant growth by alleviating plant phosphorus limitation in the tropics and nitrogen limitation in temperate regions, respectively. Our study highlights the important roles of these invertebrate taxa in global biogeochemical cycles and ecosystem functions. Given the importance of these soil-engineering invertebrates, biogeochemical models should better integrate their effects, especially on carbon fluxes and nutrient cycles.

『摘要』 白蚁、蚂蚁和蚯蚓等生物形成的结构在全球生态系统中发挥着关键作用。然而,目前对于这些体型虽小但至关重要的无脊椎动物在全球范围内引发土壤工程效应的驱动因素还知之甚少。在此,我们基于来自六大洲1047项研究的12975次观测数据的荟萃分析表明,与参照土壤相比,这三类无脊椎动物均可提高土壤的大量元素含量、土壤呼吸以及土壤微生物和植物生物量。白蚁对土壤呼吸和植物生物量的影响以及蚯蚓对土壤氮、磷含量的影响均随年平均气温的升高而增加,在热带地区达到峰值。相比之下,蚂蚁对土壤氮、土壤磷、植物生物量和存活率的影响在中纬度生态系统达到峰值,而这些地区的初级生产力最低。值得注意的是,白蚁和蚂蚁分别通过缓解热带地区的植物磷限制和温带地区的植物氮限制来促进植物生长。我们的研究强调了这些无脊椎动物类群在全球生物地球化学循环和生态系统功能中的重要作用。鉴于这些土壤工程无脊椎动物的重要性,生物地球化学模型应更好地整合其影响,尤其是对碳通量和营养循环的影响。
『总结』 研究发现白蚁、蚂蚁和蚯蚓对全球生态系统有重要影响,能增加土壤养分、促进土壤呼吸和植物生长,且其效应受气温和地理位置影响,提示生物地球化学模型需更好整合这些无脊椎动物的影响。
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『Abstract』DNA damage promotes mutations that fuel cancer, ageing and neurodegenerative diseases , but surprisingly, the causes and types of damage remain largely unknown. There are three identified mechanisms that damage DNA during transcription: collision of RNA polymerase (RNAP) with the DNA-replication machinery head-on and co-directionally , and R-loop-induced DNA breakage . Here we identify novel DNA damage reaction intermediates and uncover a fourth transcription-related source of DNA damage: endogenous DNA damage at sites of terminated transcripts. We engineered proteins to capture single-stranded DNA (ssDNA) ends with 3′ polarity in bacterial and human cells. In Escherichia coli , spontaneous 3′-ssDNA-end foci were unexpectedly frequent, at one or more per cell division, and arose via two identifiable pathways, both of which were dependent on DNA replication. A pathway associated with double-strand breaks was suppressed by overexpression of replicative DNA polymerase (pol) III, suggesting competition between pol III and DNA damage-promoting proteins. Mapping of recurrent 3′-ssDNA-ends identified distinct 3′-ssDNA-end-hotspots, mostly unrelated to double-strand breaks, next to the 5′-CCTTTTTT transcription-terminator-like sequence. These 3′-ssDNA-termini coincide with RNA 3′-termini identified by DirectRNA sequencing or simultaneous 5′ and 3′ end RNA sequencing (SEnd-seq) and were prevented by a mutant RNAP that reads through terminators. Our findings reveal that transcription termination or pausing can promote DNA damage and subsequent genomic instability.

『摘要』 DNA损伤会促进突变,进而引发癌症、衰老和神经退行性疾病,但令人惊讶的是,DNA损伤的原因和类型在很大程度上仍不明确。目前已知有三种机制会在转录过程中损伤DNA:RNA聚合酶(RNAP)与DNA复制机制发生正向和同向碰撞,以及R环诱导的DNA断裂。本研究鉴定出了新型DNA损伤反应中间体,并发现了第四种与转录相关的DNA损伤来源:转录终止位点的内源性DNA损伤。我们设计了能在细菌和人体细胞中捕获3′极性单链DNA(ssDNA)末端的蛋白质。在大肠杆菌中,自发性的3′-ssDNA末端焦点出现得意外频繁,每个细胞分裂周期中会出现一个或多个,并且通过两条可识别的途径产生,这两条途径都依赖于DNA复制。一条与双链断裂相关的途径因复制性DNA聚合酶(pol)III的过度表达而受到抑制,这表明pol III和促DNA损伤蛋白之间存在竞争关系。对复发性3′-ssDNA末端的映射发现了不同的3′-ssDNA末端热点,这些热点大多与双链断裂无关,而是位于5′-CCTTTTTT转录终止子样序列的旁边。这些3′-ssDNA末端与通过DirectRNA测序或同时进行的5′和3′端RNA测序(SEnd-seq)鉴定出的RNA 3′末端一致,并且可被一种能读取终止子的突变型RNAP所阻止。本研究结果表明,转录终止或暂停可促进DNA损伤和随后的基因组不稳定性。
『总结』 本研究发现了转录过程中一种新的DNA损伤来源,即转录终止位点的内源性DNA损伤,并揭示了转录终止或暂停可促进DNA损伤和基因组不稳定性。
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『Abstract』Globalization increasingly allows countries to externalize the environmental costs of land use, including biodiversity loss . So far, we have a very incomplete understanding of how countries cause biodiversity loss outside their own borders through their demand for agricultural and forestry products grown in other countries . Here we quantify the global range losses to forest vertebrates from 2001 to 2015 caused by deforestation attributable to 24 developed countries by means of their consumption of products obtained through global supply chains. We show that these driver countries are responsible for much greater cumulative range loss to species outside their own borders than within them. These international impacts were concentrated geographically, allowing us to map global hotspots of outsourced losses of biodiversity. Countries had the greatest external impacts on species occurring in nearby regions. However, in a few cases, developed countries also inflicted disproportionate harm on vertebrates in distant countries.

『摘要』 全球化日益使得各国能够将土地使用(包括生物多样性丧失)的环境成本外部化。迄今为止,我们对于各国如何通过其对其他国家种植的农林产品的需求而导致其他国家生物多样性丧失这一问题,还知之甚少。在此,我们通过量化2001年至2015年因24个发达国家通过全球供应链消费产品而导致的森林砍伐所造成的森林脊椎动物全球范围损失,来揭示这一问题。研究表明,这些驱动国家(即发达国家)对其国界外物种造成的累积栖息地丧失远大于对其国内物种造成的损失。这些国际影响在地理上相对集中,从而使我们能够绘制出生物多样性外包损失的全球热点图。各国对附近区域的物种产生了最大的外部影响。然而,在某些情况下,发达国家也对遥远国家的脊椎动物造成了不成比例的伤害。
『总结』 研究表明,发达国家通过全球供应链导致的森林砍伐,对国外物种造成的栖息地丧失远大于国内,且这些影响在地理上相对集中。
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『Abstract』Oncogenic mutations that drive colorectal cancer can be present in healthy intestines for long periods without overt consequence . Mutation of Apc , the most common initiating event in conventional adenomas , activates Wnt signalling, thus conferring fitness on mutant intestinal stem cells (ISCs) . Apc mutations may occur in ISCs that arise by routine self-renewal or by dedifferentiation of their progeny. Although ISCs of these different origins are fundamentally similar , it is unclear whether both generate tumours equally well in uninjured intestines. It is also unknown whether cis -regulatory elements are substantively modulated upon Wnt hyperactivation or as a feature of subsequent tumours. Here we show in two mouse models that adenomas are not an obligatory outcome of Apc deletion in either ISC source, but require proximity of mutant intestinal crypts. Reduced crypt density abrogates, and aggregation of mutant colonic crypts augments, adenoma formation. Moreover, adenoma-resident ISCs open chromatin at thousands of enhancers that are inaccessible in Apc -null ISCs that are not associated with adenomas. These cis elements explain adenoma-selective gene activity and persist, with little further expansion of the repertoire, as other oncogenic mutations accumulate. Thus, cooperativity between neighbouring mutant crypts and new accessibility at specific enhancers are key steps early in intestinal tumorigenesis.

『摘要』 致癌突变可长期存在于健康肠道中而不产生明显后果。Apc突变是传统腺瘤中最常见的始发事件,可激活Wnt信号通路,从而使突变肠道干细胞(ISCs)具有适应性。Apc突变可能发生在通过常规自我更新或子代细胞去分化而产生的ISCs中。虽然这些不同来源的ISCs在根本上相似,但尚不清楚它们在未受损的肠道中是否具有同等的致瘤能力。目前也不清楚顺式调控元件是否在Wnt过度激活时被实质性调控,或者这是否是后续肿瘤的特征。在本研究中,我们通过两种小鼠模型发现,无论ISCs来源如何,腺瘤都不是Apc缺失的必然结果,而是需要突变肠道隐窝的邻近性。隐窝密度降低会阻止腺瘤的形成,而突变结肠隐窝的聚集则会促进腺瘤的形成。此外,腺瘤驻留ISCs可在数千个增强子处打开染色质,而这些增强子在未与腺瘤相关的Apc缺失ISCs中是不可接近的。这些顺式元件解释了腺瘤选择性基因活性,并随着其他致癌突变的积累而持续存在,且其谱系几乎不会进一步扩展。因此,邻近突变隐窝之间的协同作用和特定增强子处的新可及性是肠道肿瘤发生早期的关键步骤。
『总结』 研究显示,Apc突变导致的肠道肿瘤形成需邻近突变隐窝及特定增强子处染色质开放,这两个因素共同构成了肠道肿瘤发生的早期关键步骤。
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『Abstract』T cell-based immunotherapies hold promise in treating cancer by leveraging the immune system’s recognition of cancer-specific antigens . However, their efficacy is limited in tumours with few somatic mutations and substantial intratumoural heterogeneity . Here we introduce a previously uncharacterized class of tumour-wide public neoantigens originating from RNA splicing aberrations in diverse cancer types. We identified T cell receptor clones capable of recognizing and targeting neoantigens derived from aberrant splicing in GNAS and RPL22 . In cases with multi-site biopsies, we detected the tumour-wide expression of the GNAS neojunction in glioma, mesothelioma, prostate cancer and liver cancer. These neoantigens are endogenously generated and presented by tumour cells under physiologic conditions and are sufficient to trigger cancer cell eradication by neoantigen-specific CD8 T cells. Moreover, our study highlights a role for dysregulated splicing factor expression in specific cancer types, leading to recurrent patterns of neojunction upregulation. These findings establish a molecular basis for T cell-based immunotherapies addressing the challenges of intratumoural heterogeneity.

『摘要』 基于T细胞的免疫疗法通过利用免疫系统对癌症特异性抗原的识别来治疗癌症,前景可期。然而,对于体细胞突变较少且肿瘤内异质性显著的肿瘤,其疗效有限。本研究介绍了一类以前未表征的肿瘤广泛性公共新抗原,它们来源于多种癌症类型中的RNA剪接异常。我们发现了能够识别并靶向GNAS和RPL22中异常剪接产生的新抗原的T细胞受体克隆。在多部位活检的病例中,我们在胶质瘤、间皮瘤、前列腺癌和肝癌中检测到了GNAS新连接点的肿瘤广泛性表达。这些新抗原是在生理条件下由肿瘤细胞内生产生并呈递的,足以触发新抗原特异性CD8 T细胞对癌细胞的清除。此外,本研究还强调了特定癌症类型中剪接因子表达失调的作用,这导致了新连接点上调的重复模式。这些发现为应对肿瘤内异质性挑战的基于T细胞的免疫疗法奠定了分子基础。
『总结』 本研究发现了一类源于RNA剪接异常的肿瘤广泛性新抗原,它们可触发T细胞对多种癌症的免疫反应,为基于T细胞的免疫疗法提供了新的分子基础。
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『Abstract』Cognitive maps confer animals with flexible intelligence by representing spatial, temporal and relationships that can be used to shape thought, planning and behaviour. Cognitive maps have been observed in the hippocampus , but their algorithmic form and learning mechanisms remain obscure. Here we used large-scale, longitudinal two-photon calcium imaging to record activity from thousands of neurons in the CA1 region of the hippocampus while mice learned to efficiently collect rewards from two subtly different linear tracks in virtual reality. Throughout learning, both animal behaviour and hippocampal neural activity progressed through multiple stages, gradually revealing improved task representation that mirrored improved behavioural efficiency. The learning process involved progressive decorrelations in initially similar hippocampal neural activity within and across tracks, ultimately resulting in orthogonalized representations resembling a state machine capturing the inherent structure of the task. This decorrelation process was driven by individual neurons acquiring task-state-specific responses (that is, ‘state cells’). Although various standard artificial neural networks did not naturally capture these dynamics, the clone-structured causal graph, a hidden Markov model variant, uniquely reproduced both the final orthogonalized states and the learning trajectory seen in animals. The observed cellular and population dynamics constrain the mechanisms underlying cognitive map formation in the hippocampus, pointing to hidden state inference as a fundamental computational principle, with implications for both biological and artificial intelligence.

『摘要』 认知地图通过表示空间、时间和抽象关系赋予动物灵活的智力,这些关系可用于塑造思维、规划行为。已有研究在海马体中观察到认知地图,但其算法形式和学习机制仍不明确。本研究利用大规模、纵向双光子钙成像技术,记录了小鼠在虚拟现实中学习高效地从两条细微不同的线性轨道上收集奖励时,海马体CA1区域数千个神经元的活动。在学习过程中,动物行为和海马体神经活动均经历了多个阶段,逐渐呈现出任务表征的改善,这反映了行为效率的提高。学习过程涉及轨道内和轨道间初始相似的海马体神经活动逐渐去相关,最终形成正交表征,类似于捕获任务固有结构的状态机。这种去相关过程是由单个神经元获得任务状态特异性反应(即“状态细胞”)驱动的。虽然各种标准的人工神经网络无法自然地捕获这些动态变化,但克隆结构因果图(一种隐马尔可夫模型变体)唯一地再现了动物身上观察到的最终正交状态和学习轨迹。观察到的细胞和群体动力学限制了海马体中认知地图形成机制的范围,指出了隐藏状态推断作为一种基本计算原则,对生物智能和人工智能都有启示意义。
『总结』 本研究揭示了海马体中认知地图的学习机制,发现其通过神经元去相关和状态细胞的形成实现任务表征的改善,并指出隐藏状态推断是这一过程中的基本计算原则。
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『Abstract』Bacteriophages use diverse mechanisms to evade antiphage defence systems. ΦKZ-like jumbo phages assemble a proteinaceous, nucleus-like compartment that excludes antagonistic host nucleases and also internalizes DNA replication and transcription machinery . The phage factors required for protein import and the mechanisms of selectivity remain unknown, however. Here we uncover an import system comprising proteins highly conserved across nucleus-forming phages, together with additional cargo-specific contributors. Using a genetic selection that forces the phage to decrease or abolish the import of specific proteins, we determine that the importation of five different phage nuclear-localized proteins requires distinct interfaces of the same factor, Imp1 (gp69). Imp1 localizes early to the nascent phage nucleus and forms discrete puncta in the mature phage nuclear periphery, probably in complex with direct interactor Imp6 (gp67), a conserved protein encoded in the same locus. The import of certain proteins, including a host topoisomerase, additionally requires Imp3 (gp59), a conserved factor necessary for proper Imp1 function. Three additional non-conserved phage proteins (Imp2 and Imp4/Imp5) are required for the import of two queried nuclear cargos (nuclear-localized protein 1 and host topoisomerase, respectively), perhaps acting as specific adaptors. We therefore propose a core import system that includes Imp1, Imp3 and Imp6, with multiple interfaces of Imp1 licensing transport through a protein lattice.

『摘要』 噬菌体采用多种机制来规避宿主的抗噬菌体防御系统。ΦKZ样巨型噬菌体会组装一个蛋白质性质的、类似细胞核的区室,该区室将宿主中对抗性的核酸酶排除在外,并将DNA复制和转录机制纳入其中。然而,蛋白质导入所需的噬菌体因子以及选择性机制仍不清楚。本研究揭示了一种导入系统,该系统由在成核噬菌体中高度保守的蛋白质以及额外的货物特异性贡献因子组成。我们使用一种遗传选择方法,迫使噬菌体减少或消除特定蛋白质的导入,并据此确定五种不同的噬菌体核定位蛋白质的导入需要同一因子Imp1(gp69)的不同界面。Imp1在噬菌体核新生时便早期定位其中,并在成熟的噬菌体核外周形成离散的点状结构,可能与直接相互作用因子Imp6(gp67)(一种在同一基因座编码的保守蛋白质)形成复合物。某些蛋白质(包括宿主拓扑异构酶)的导入还需要Imp3(gp59),这是Imp1正常功能所需的保守因子。另外还需要三种非保守的噬菌体蛋白质(Imp2和Imp4/Imp5)来导入两种被检测的核货物(分别为核定位蛋白质1和宿主拓扑异构酶),它们可能作为特异性接头蛋白发挥作用。因此,本研究提出了一个核心导入系统,该系统包括Imp1、Imp3和Imp6,其中Imp1的多个界面通过蛋白质晶格授权运输。
『总结』 本研究揭示了一种噬菌体核心导入系统,包含Imp1、Imp3和Imp6等关键因子,并阐明了Imp1的多个界面在蛋白质导入中的重要作用。
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『Abstract』Glaciers are indicators of ongoing anthropogenic climate change . Their melting leads to increased local geohazards , and impacts marine and terrestrial ecosystems, regional freshwater resources , and both global water and energy cycles . Together with the Greenland and Antarctic ice sheets, glaciers are essential drivers of present and future sea-level rise. Previous assessments of global glacier mass changes have been hampered by spatial and temporal limitations and the heterogeneity of existing data series . Here we show in an intercomparison exercise that glaciers worldwide lost 273 ± 16 gigatonnes in mass annually from 2000 to 2023, with an increase of 36 ± 10% from the first (2000–2011) to the second (2012–2023) half of the period. Since 2000, glaciers have lost between 2% and 39% of their ice regionally and about 5% globally. Glacier mass loss is about 18% larger than the loss from the Greenland Ice Sheet and more than twice that from the Antarctic Ice Sheet . Our results arise from a scientific community effort to collect, homogenize, combine and analyse glacier mass changes from in situ and remote-sensing observations. Although our estimates are in agreement with findings from previous assessments at a global scale, we found some large regional deviations owing to systematic differences among observation methods. Our results provide a refined baseline for better understanding observational differences and for calibrating model ensembles , which will help to narrow projection uncertainty for the twenty-first century .

『摘要』 冰川是持续人为气候变化的指标。冰川融化会导致当地地质灾害增加,影响海洋和陆地生态系统、区域淡水资源以及全球水和能源循环。与格陵兰和南极冰盖一起,冰川是当前和未来海平面上升的重要驱动因素。以往对全球冰川质量变化的评估一直受到空间和时间限制以及现有数据序列异质性的阻碍。在本研究的相互比较中,我们发现2000年至2023年期间,全球冰川每年质量损失273±160亿吨,从前半期(2000~2011年)到后半期(2012~2023年)增加了36±10%。自2000年以来,各区域冰川的冰量损失在2%至39%之间,全球平均损失约5%。冰川质量损失比格陵兰冰盖损失的多约18%,比南极冰盖损失的多两倍以上。我们的研究结果源于科学界对基于实地和遥感观测的冰川质量变化数据进行收集、均一化、整合和分析的共同努力。虽然我们的估计与以往全球评估的结果一致,但由于观测方法之间的系统性差异,我们发现了一些较大的区域偏差。我们的研究结果为更好地理解观测差异和校准模型集合提供了一个更精确的基准,这将有助于缩小对二十一世纪预测的不确定性。
『总结』 研究显示2000年至2023年全球冰川年质量损失显著,且后半期比前半期增加,该结果有助于减小对二十一世纪气候变化预测的不确定性。
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『Abstract』A hallmark of pulmonary fibrosis is the aberrant activation of lung fibroblasts into pathological fibroblasts that produce excessive extracellular matrix . Thus, the identification of key regulators that promote the generation of pathological fibroblasts can inform the development of effective countermeasures against disease progression. Here we use two mouse models of pulmonary fibrosis to show that LEPR fibroblasts that arise during alveologenesis include SCUBE2 alveolar fibroblasts as a major constituent. These alveolar fibroblasts in turn contribute substantially to CTHRC1 POSTN pathological fibroblasts. Genetic ablation of POSTN pathological fibroblasts attenuates fibrosis. Comprehensive analyses of scRNA-seq and scATAC-seq data reveal that RUNX2 is a key regulator of the expression of fibrotic genes. Consistently, conditional deletion of Runx2 with Lepr or Scube2 reduces the generation of pathological fibroblasts, extracellular matrix deposition and pulmonary fibrosis. Therefore, LEPR cells that include SCUBE2 alveolar fibroblasts are a key source of pathological fibroblasts, and targeting Runx2 provides a potential treatment option for pulmonary fibrosis.

『摘要』 肺纤维化的一个标志是肺成纤维细胞异常激活成为能产生过量细胞外基质的病理成纤维细胞。因此,鉴定出促进病理成纤维细胞生成的关键调节因子可为制定阻止疾病进展的有效对策提供依据。本研究使用两种肺纤维化小鼠模型证明,在肺泡生成过程中出现的LEPR成纤维细胞主要包括SCUBE2肺泡成纤维细胞。这些肺泡成纤维细胞会大量转化为CTHRC1 POSTN病理成纤维细胞。遗传消融POSTN病理成纤维细胞可减轻纤维化。对单细胞RNA测序(scRNA-seq)和单细胞转录组可接近性测序(scATAC-seq)数据的综合分析显示,RUNX2是纤维化基因表达的关键调节因子。同样,利用Lepr或Scube2条件性敲除Runx2可减少病理成纤维细胞的生成、细胞外基质沉积和肺纤维化。因此,包括SCUBE2肺泡成纤维细胞在内的LEPR细胞是病理成纤维细胞的关键来源,靶向Runx2为肺纤维化提供了一种潜在的治疗选择。
『总结』 研究发现LEPR细胞是肺纤维化中病理成纤维细胞的关键来源,靶向Runx2或为治疗肺纤维化提供新选择。
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『Abstract』Modular structure and function are ubiquitous in biology, from the organization of animal brains and bodies to the scale of ecosystems. However, the mechanisms of modularity emergence from non-modular precursors remain unclear. Here we introduce the principle of peak selection, a process by which purely local interactions and smooth gradients can drive the self-organization of discrete global modules. The process combines strengths of the positional and Turing pattern-formation mechanisms into a model for morphogenesis. Applied to the grid-cell system of the brain, peak selection results in the self-organization of functionally distinct modules with discretely spaced spatial periods. Applied to ecological systems, it results in discrete multispecies niches and synchronous spawning across geographically distributed coral colonies. The process exhibits self-scaling with system size and ‘topological robustness’ , which renders module emergence and module properties insensitive to most parameters. Peak selection ameliorates the fine-tuning requirement for continuous attractor dynamics in single grid-cell modules and it makes a detail-independent prediction that grid module period ratios should approximate adjacent integer ratios, providing a highly accurate match to the available data. Predictions for grid cells at the transcriptional, connectomic and physiological levels promise to elucidate the interplay of molecules, connectivity and function emergence in brains.

『摘要』 生物界中普遍存在着模块化结构和功能,从动物的大脑和身体组织到生态系统规模均有所体现。然而,模块如何从非模块化前体中出现,其机制仍不清楚。本文提出了峰值选择原理,即通过纯粹的局部相互作用和平滑梯度可以驱动离散全局模块的自组织。这一过程将位置模式和图灵模式形成机制的优点结合到一个形态发生模型中。将该过程应用于大脑中的网格细胞系统,峰值选择会导致具有离散空间周期的功能不同模块的自组织。将其应用于生态系统,则会产生离散的多物种生态位和地理上分布的珊瑚种群的同步产卵。该过程表现出随系统大小而变化的自缩放性和“拓扑鲁棒性”,这使得模块的出现和模块属性对大多数参数不敏感。峰值选择改善了单网格细胞模块中连续吸引子动力学的精细调整要求,并且它做出了一个与细节无关的预测,即网格模块周期比应接近相邻整数比,这与现有数据高度吻合。对网格细胞在转录、连接组和生理水平上的预测有望阐明大脑中分子、连接和功能出现之间的相互作用。
『总结』 峰值选择原理揭示了生物模块化结构和功能的自组织机制,改善了模块动力学调整,准确预测了模块周期比,并有望阐明大脑中分子、连接与功能的相互作用。
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『Abstract』The composition and organization of the cell surface determine how cells interact with their environment. Traditionally, glycosylated transmembrane proteins were thought to be the major constituents of the external surface of the plasma membrane. Here, we provide evidence that a group of RNA-binding proteins (RBPs) is present on the surface of living cells. These cell-surface RBPs (csRBPs) precisely organize into well-defined nanoclusters enriched for multiple RBPs and glycoRNAs, and their clustering can be disrupted by extracellular RNase addition. These glycoRNA-csRBP clusters further serve as sites of cell-surface interaction for the cell-penetrating peptide trans -activator of transcription (TAT). Removal of RNA from the cell surface, or loss of RNA-binding activity by TAT, causes defects in TAT cell internalization. Together, we provide evidence of an expanded view of the cell surface by positioning glycoRNA-csRBP clusters as a regulator of communication between cells and the extracellular environment.

『摘要』 细胞表面的组成和结构决定了细胞如何与环境相互作用。传统观点认为,糖基化跨膜蛋白是质膜外表面的主要成分。本研究提供证据表明,一组RNA结合蛋白(RBPs)存在于活细胞表面。这些细胞表面RNA结合蛋白(csRBPs)精准地组织成含有多种RBPs和糖基化RNA(glycoRNAs)的明确定义的纳米簇,而这些纳米簇的结构可被细胞外添加的核糖核酸酶破坏。这些glycoRNA-csRBP簇进一步作为细胞穿透肽——转录反式激活因子(TAT)与细胞表面相互作用的位点。从细胞表面去除RNA或TAT丧失RNA结合活性,都会导致TAT细胞内化缺陷。总的来说,本研究通过将glycoRNA-csRBP簇定位为细胞与细胞外环境通讯的调节因子,为扩展细胞表面的认知提供了证据。
『总结』 本研究发现细胞表面存在RNA结合蛋白组成的纳米簇,这些簇是细胞与环境相互作用的新位点,并参与调节细胞内化过程。
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『Abstract』Coenzyme Q (CoQ) is essential for energy production by mitochondrial respiration, and it is a supplement most often used to promote cardiovascular health. Humans make CoQ 10 , but cereals and some vegetable/fruit crops synthesize CoQ 9 with a side chain of nine isoprene units. Engineering CoQ 10 production in crops would benefit human health, but this is hindered by the fact that the specific residues of the enzyme Coq1 that control chain length are unknown. Based on an extensive investigation of the distribution of CoQ 9 and CoQ 10 in land plants and the associated Coq1 sequence variation, we identified key amino acid changes at the base of the Coq1 catalytic pocket that occurred independently in multiple angiosperm lineages and repeatedly drove CoQ 9 formation. Guided by this knowledge, we used gene editing to modify the native Coq1 genes of rice and wheat to produce CoQ 10 , paving the way for developing additional dietary sources of CoQ 10 .

『摘要』 辅酶Q(CoQ)对于线粒体呼吸产生的能量至关重要,它是最常用的促进心血管健康的补充剂。人体能合成辅酶Q10 (CoQ 10),但谷物和一些蔬果作物合成的却是含有九个异戊二烯单元的侧链的辅酶Q9 (CoQ 9)。在作物中工程化生产辅酶Q10将有利于人类健康,但目前尚不清楚控制链长的Coq1酶的具体残基,阻碍了这一过程。基于对陆生植物中辅酶Q9和辅酶Q10的分布以及相关Coq1序列变异的广泛研究,我们确定了位于Coq1催化口袋底部的关键氨基酸变化,这些变化在多个被子植物谱系中独立发生,并多次驱动了辅酶Q9的形成。基于这一发现,我们利用基因编辑技术修改了水稻和小麦中的本土Coq1基因,使其生产辅酶Q10,为开发更多辅酶Q10膳食来源铺平了道路。
『总结』 研究通过基因编辑技术修改了水稻和小麦中的Coq1基因,成功使其生产辅酶Q10,为人类健康提供了更多膳食来源。
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『Abstract』Cancer cells acquire numerous mutations during tumorigenesis, including synonymous mutations that do not change the amino acid sequence of a protein. RNA N6-methyladenosine (m A) is a post-transcriptional modification that plays critical roles in oncogenesis. Herein, we identified 12,849 mutations in the cancer genome with the potential to perturb m A modification patterns, which we refer to as “m A disruption mutations (m A-DMs).” These are either synonymous m A-DMs (sm A-DMs) or missense m A-DMs (mm A-DMs) mutations, and the former is enriched within tumor suppressor genes, such as CDKN2A and BRCA2. Using epitranscriptomic editing, we demonstrate that manipulating m A levels at specific sm A-DM sites influences mRNA stability. Furthermore, introducing CDKN2A sm A-DMs into cancer cells promotes tumor growth while BRCA2 sm A-DMs sensitize tumors to the poly (ADP-ribose) polymerase inhibitor (PARPi) treatment. Our findings demonstrate sm A-DMs as potential oncogenic drivers, unveiling implications for synonymous mutations in tumorigenesis and beyond.

『摘要』 在肿瘤发生过程中,癌细胞会获得大量突变,包括不影响蛋白质氨基酸序列的同义突变。RNA N6-甲基腺苷(mA)是一种转录后修饰,在肿瘤发生中起着关键作用。本研究在癌症基因组中确定了12849个可能扰乱mA修饰模式的突变,我们称之为“mA破坏突变(mA-DMs)”。这些突变包括同义mA-DMs(smA-DMs)和错义mA-DMs(mmA-DMs),其中前者在肿瘤抑制基因(如CDKN2A和BRCA2)中更为丰富。通过表观转录组编辑技术,我们证明在特定的smA-DM位点调节mA水平会影响mRNA的稳定性。此外,将CDKN2A smA-DMs引入癌细胞可促进肿瘤生长,而将BRCA2 smA-DMs引入癌细胞则使肿瘤对聚(ADP-核糖)聚合酶抑制剂(PARPi)治疗敏感。我们的研究结果表明,smA-DMs可能是潜在的致癌驱动因素,揭示了同义突变在肿瘤发生及其他方面的意义。
『总结』 本研究发现了癌症中可能改变mA修饰模式的突变,并证明特定的同义mA-DMs可影响mRNA稳定性和肿瘤生物学特性,揭示了同义突变在肿瘤发生中的潜在作用。
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『Abstract』Despite ongoing efforts to study CRISPR systems, the evolutionary origins giving rise to reprogrammable RNA-guided mechanisms remain poorly understood. Here, we describe an integrated sequence/structure evolutionary tracing approach to identify the ancestors of the RNA-targeting CRISPR-Cas13 system. We find that Cas13 likely evolved from AbiF, which is encoded by an abortive infection-linked gene that is stably associated with a conserved non-coding RNA (ncRNA). We further characterize a miniature Cas13, classified here as Cas13e, which serves as an evolutionary intermediate between AbiF and other known Cas13s. Despite this relationship, we show that their functions substantially differ. Whereas Cas13e is an RNA-guided RNA-targeting system, AbiF is a toxin-antitoxin (TA) system with an RNA antitoxin. We solve the structure of AbiF using cryoelectron microscopy (cryo-EM), revealing basic structural alterations that set Cas13s apart from AbiF. Finally, we map the key structural changes that enabled a non-guided TA system to evolve into an RNA-guided CRISPR system.

『摘要』 尽管人们一直在努力研究CRISPR系统,但对可编程RNA引导机制的进化起源仍知之甚少。本文描述了一种综合的序列/结构进化追溯方法,用于鉴定RNA靶向CRISPR-Cas13系统的祖先。我们发现,Cas13可能由AbiF进化而来,AbiF由一个与流产感染相关的基因编码,该基因与一个保守的非编码RNA(ncRNA)稳定相关。我们进一步表征了一种微型Cas13,此处将其分类为Cas13e,它是AbiF和其他已知Cas13之间的进化中间体。尽管存在这种关系,但我们的研究表明它们的功能存在显著差异。Cas13e是一种RNA引导的RNA靶向系统,而AbiF则是一种带有RNA抗毒素的毒素-抗毒素(TA)系统。我们使用冷冻电子显微镜(cryo-EM)解析了AbiF的结构,揭示了使Cas13与AbiF区别开来的基本结构变化。最后,我们绘制了使非引导型TA系统进化为RNA引导型CRISPR系统的关键结构变化图。
『总结』 本研究揭示了CRISPR-Cas13系统可能的进化起源,即其可能由AbiF进化而来,并阐明了从非引导型TA系统到RNA引导型CRISPR系统的关键结构变化。
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『Abstract』The Sec translocon is vital for guiding membrane protein insertion into lipid bilayers. The insertion and folding processes of membrane proteins are poorly understood. Here, we report cryo-electron microscopy structures of multi-spanning membrane proteins inserting through the SecY channel, the Sec translocon in prokaryotes. The high-resolution structures illustrate how bulky amino acids pass the narrow channel restriction. Comparison of different translocation states reveals that the cytoplasmic and extracellular cavities of the channel create distinct environments for promoting the unfolding and folding of transmembrane segments (TMs), respectively. Released substrate TMs are either flexible or stabilized by an unexpected hydrophilic groove between TM3 and TM4 of SecY. Disruption of the groove causes global defects in the folding of the membrane proteome. These findings demonstrate that beyond its role as a passive protein-conducting channel, the SecY translocon actively serves as a chaperone, employing multiple mechanisms to promote membrane protein insertion and folding.

『摘要』 Sec转运子对于引导膜蛋白插入脂质双分子层至关重要。膜蛋白的插入和折叠过程尚不完全清楚。在此,我们报告了通过原核生物Sec转运子SecY通道插入的多跨膜蛋白的冷冻电子显微镜结构。高分辨率结构阐释了庞大的氨基酸如何通过狭窄的通道限制。对不同转运状态的比较显示,通道的胞质和胞外空腔分别为促进跨膜段(TMs)的展开和折叠创造了不同的环境。释放的底物跨膜段要么是柔性的,要么被SecY中TM3和TM4之间一个意外的亲水凹槽所稳定。该凹槽的破坏会导致膜蛋白组折叠出现全局性缺陷。这些发现表明,除了作为被动蛋白质传导通道的作用外,SecY转运子还积极充当伴侣蛋白,采用多种机制促进膜蛋白的插入和折叠。
『总结』 研究表明SecY转运子不仅作为膜蛋白插入的通道,还通过多种机制主动促进膜蛋白的插入和折叠。
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『Abstract』Space habitation provides unique challenges in built environments isolated from Earth. We produced a 3D map of the microbes and metabolites throughout the United States Orbital Segment (USOS) of the International Space Station (ISS) with 803 samples collected during space flight, including controls. We find that the use of each of the nine sampled modules within the ISS strongly drives the microbiology and chemistry of the habitat. Relating the microbiology to other Earth habitats, we find that, as with human microbiota, built environment microbiota also align naturally along an axis of industrialization, with the ISS providing an extreme example of an industrialized environment. We demonstrate the utility of culture-independent sequencing for microbial risk monitoring, especially as the location of sequencing moves to space. The resulting resource of chemistry and microbiology in the space-built environment will guide long-term efforts to maintain human health in space for longer durations.

『摘要』 在国际空间站(ISS)的美国轨道舱段(USOS)中,太空居住环境因其与地球隔绝而带来了独特的挑战。我们通过在太空飞行期间收集的803个样本(包括对照组)制作了国际空间站美国轨道舱段微生物和代谢物的3D地图。我们发现,国际空间站内九个被采样模块的使用情况对居住环境的微生物学和化学特性有着重要影响。在将太空中的微生物学与其他地球栖息地进行比较时,我们发现,与人体微生物群一样,建筑环境中的微生物群也自然地沿着工业化轴线分布,而国际空间站则是一个极端的工业化环境示例。我们证明了培养非依赖性测序在微生物风险监测中的实用性,尤其是当测序地点转移到太空时。太空建筑环境中的化学和微生物学资源将为未来长时间维持太空人类健康的长期工作提供指导。
『总结』 本研究通过对国际空间站美国轨道舱段的微生物和代谢物进行3D绘图,揭示了太空居住环境独特的微生物学和化学特性,并强调了培养非依赖性测序在太空微生物风险监测中的重要性。
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『Abstract』Parasitism with Striga poses a major threat to global food production. Striga germination and growth rely on strigolactones (SLs) exuded by crop roots under phosphate (Pi)-deficient conditions, although the mechanism of this host-parasite interaction remains elusive. In this study, transcriptomic and functional analyses of sorghum treated with Pi deficiency or the SL GR24 identify two ABC transporter G (ABCG) transporters of SL, Sorghum biocolor strigolactones transporter 1 (SbSLT1) and SbSLT2. Using AlphaFold2 and amino acid conversion mutants, we identify highly conserved amino acids in SL transport channels essential for transport function. Sorghum lines with single or double knockouts of these transporters exhibit significantly reduced SL secretion from roots, leading to decreased Striga germination and parasitism in field experiments and consequently reducing the grain loss under Striga infestation. This study thus describes the mechanism of SL exudation in monocots and defines conserved residues essential for SL transporter function, offering a potential strategy for enhancing crop resistance to Striga parasitism.

『摘要』 磷酸盐缺乏时,作物根系会分泌独脚金内酯 (strigolactones,SLs),而列当 (Striga) 的萌发和生长依赖于此,这对全球粮食生产构成了重大威胁,尽管这种寄主-寄生相互作用的机制仍不清楚。本研究对缺磷或经独脚金内酯GR24处理的高粱进行了转录组和功能分析,鉴定出两种独脚金内酯的ABC转运蛋白G (ABCG),即高粱独脚金内酯转运蛋白1 (SbSLT1) 和SbSLT2。利用AlphaFold2和氨基酸转换突变体,本研究鉴定出了独脚金内酯转运通道中对转运功能至关重要的高度保守氨基酸。在田间试验中,这些转运蛋白的单基因或双基因敲除高粱品系的根系分泌独脚金内酯显著减少,导致列当萌发和寄生现象减少,进而减少了列当侵染导致的粮食损失。因此,本研究阐述了单子叶植物中独脚金内酯渗出的机制,并确定了独脚金内酯转运蛋白功能所必需的高度保守残基,为增强作物对列当寄生的抗性提供了一种潜在策略。
『总结』 本研究揭示了单子叶植物独脚金内酯渗出的机制,鉴定了关键转运蛋白,为提高作物抗列当寄生提供了新策略。
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『Abstract』Vitamin C (vitC) is essential for health and shows promise in treating diseases like cancer, yet its mechanisms remain elusive. Here, we report that vitC directly modifies lysine residues to form “vitcyl-lysine”—a process termed vitcylation. Vitcylation occurs in a dose-, pH-, and sequence-dependent manner in both cell-free systems and living cells. Mechanistically, vitC vitcylates signal transducer and activator of transcription-1 (STAT1)- lysine-298 (K298), impairing its interaction with T cell protein-tyrosine phosphatase (TCPTP) and preventing STAT1-Y701 dephosphorylation. This leads to enhanced STAT1-mediated interferon (IFN) signaling in tumor cells, increased major histocompatibility complex (MHC)/human leukocyte antigen (HLA) class I expression, and activation of anti-tumor immunity in vitro and in vivo . The discovery of vitcylation as a distinctive post-translational modification provides significant insights into vitC’s cellular function and therapeutic potential, opening avenues for understanding its biological effects and applications in disease treatment.

『摘要』 维生素C(vitC)对健康至关重要,并有望用于治疗癌症等疾病,然而其作用机制仍不明确。本研究报道,维生素C可直接修饰赖氨酸残基形成“维生素C赖氨酸”(vitcyl-lysine),这一过程被称为维生素C化修饰(vitcylation)。维生素C化修饰在无细胞系统和活细胞中均以剂量、pH值和序列依赖的方式发生。从机制上讲,维生素C使信号转导子和转录激活子1(STAT1)的第298位赖氨酸(K298)发生维生素C化修饰,损害其与T细胞蛋白酪氨酸磷酸酶(TCPTP)的相互作用,并阻止STAT1-Y701去磷酸化。这导致肿瘤细胞中STAT1介导的干扰素(IFN)信号增强、主要组织相容性复合体(MHC)/人类白细胞抗原(HLA)I类表达增加,以及体外和体内抗肿瘤免疫力激活。维生素C化修饰作为一种独特的翻译后修饰,为深入理解维生素C的细胞功能和治疗潜力提供了重要见解,为理解其在疾病治疗中的生物学效应和应用开辟了新途径。
『总结』 研究发现维生素C可通过维生素C化修饰增强抗肿瘤免疫力,为维生素C的细胞功能和疾病治疗应用提供了新视角。
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『Abstract』Plants are composed of diverse secondary metabolites (PSMs), which are widely associated with human health. Whether and how the gut microbiome mediates such impacts of PSMs is poorly understood. Here, we show that discrete dietary and medicinal phenolic glycosides, abundant health-associated PSMs, are utilized by distinct members of the human gut microbiome. Within the Bacteroides , the predominant gram-negative bacteria of the Western human gut, we reveal a specialized multi-enzyme system dedicated to the processing of distinct glycosides based on structural differences in phenolic moieties. This Bacteroides metabolic system liberates chemically distinct aglycones with diverse biological functions, such as colonization resistance against the gut pathogen Clostridioides difficile via anti-microbial activation of polydatin to the stilbene resveratrol and intestinal homeostasis via activation of salicin to the immunoregulatory aglycone saligenin. Together, our results demonstrate generation of biological diversity of phenolic aglycone “effector” functions by a distinct gut-microbiome-encoded PSM-processing system.

『摘要』 植物由多种次生代谢产物(PSMs)组成,这些代谢物与人类的健康息息相关。然而,肠道微生物群是否以及如何介导PSMs的这些影响,目前尚不清楚。本研究表明,人类肠道微生物群中不同的成员可以利用不同的饮食和药用酚类糖苷——一类丰富的与健康相关的PSMs。在西方人群的肠道中,拟杆菌属是主要的革兰氏阴性菌,我们发现其拥有一套专门的多酶系统,可基于酚类部分的结构差异来处理不同的糖苷。这一拟杆菌代谢系统能够释放具有不同生物功能的化学性质独特的苷元,例如通过将白藜芦醇苷抗微生物活化为白藜芦醇来抵抗肠道病原体艰难梭菌的定植,以及通过将水杨苷活化为具有免疫调节作用的苷元水杨苷原来维持肠道稳态。总体而言,我们的研究结果表明,一个独特的肠道微生物群编码的PSMs处理系统产生了具有生物多样性的酚类苷元“效应”功能。
『总结』 本研究发现肠道微生物群能够利用并转化酚类糖苷,生成具有多种生物功能的苷元,揭示了肠道微生物群在介导植物次生代谢产物对人体健康影响中的重要作用。
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『Abstract』Clear cell renal cell carcinoma (ccRCC), despite having a low mutational burden, is considered immunogenic because it occasionally undergoes spontaneous regressions and often responds to immunotherapies. The signature lesion in ccRCC is inactivation of the VHL tumor suppressor gene and consequent upregulation of the HIF transcription factor. An earlier case report described a ccRCC patient who was cured by an allogeneic stem cell transplant and later found to have donor-derived T cells that recognized a ccRCC-specific peptide encoded by a HIF-responsive endogenous retrovirus (ERV), ERVE-4. We report that ERVE-4 is one of many ERVs that are induced by HIF, translated into HLA-bound peptides in ccRCCs, and capable of generating antigen-specific T cell responses. Moreover, ERV expression can be induced in non-ccRCC tumors with clinical-grade HIF stabilizers. These findings have implications for leveraging ERVs for cancer immunotherapy.

『摘要』 透明细胞肾细胞癌(ccRCC)尽管突变负荷较低,但由于其偶尔会发生自发性消退且通常对免疫治疗有反应,因此被认为具有免疫原性。ccRCC的特征性病变是VHL抑癌基因的失活以及随之而来的HIF转录因子上调。早期的一份病例报告描述了一名ccRCC患者,该患者通过异基因干细胞移植治愈,后来发现其体内有来源于供体的T细胞,这些T细胞能够识别由HIF反应性内源性逆转录病毒(ERV)ERVE-4编码的ccRCC特异性肽。我们报告称,ERVE-4是HIF诱导的众多ERV之一,可在ccRCC中被翻译成HLA结合肽,并能够产生抗原特异性T细胞反应。此外,使用临床级HIF稳定剂可在非ccRCC肿瘤中诱导ERV表达。这些发现对利用ERV进行癌症免疫治疗具有重要意义。
『总结』 研究发现ERVE-4等内源性逆转录病毒可被HIF诱导并在ccRCC中产生抗原特异性T细胞反应,非ccRCC肿瘤中也可通过HIF稳定剂诱导ERV表达,这对癌症免疫治疗具有潜在价值。
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『Abstract』Bacterial immunotherapy holds promising cancer-fighting potential. However, unlocking its power requires a mechanistic understanding of how bacteria both evade antimicrobial immune defenses and stimulate anti-tumor immune responses within the tumor microenvironment (TME). Here, by harnessing an engineered Salmonella enterica strain with this dual proficiency, we unveil an underlying singular mechanism. Specifically, the hysteretic nonlinearity of interleukin-10 receptor (IL-10R) expression drives tumor-infiltrated immune cells into a tumor-specific IL-10R state. Bacteria leverage this to enhance tumor-associated macrophages producing IL-10, evade phagocytosis by tumor-associated neutrophils, and coincidently expand and stimulate the preexisting exhausted tumor-resident CD8 T cells. This effective combination eliminates tumors, prevents recurrence, and inhibits metastasis across multiple tumor types. Analysis of human samples suggests that the IL-10R state might be a ubiquitous trait across human tumor types. Our study unveils the unsolved mechanism behind bacterial immunotherapy’s dual challenge in solid tumors and provides a framework for intratumoral immunomodulation.

『摘要』 细菌免疫疗法在抗癌方面展现出巨大潜力。然而,要充分发挥其作用,就需要深入了解细菌如何逃避抗菌免疫防御机制以及在肿瘤微环境(TME)中刺激抗肿瘤免疫反应。本研究利用一种具备这两种能力的工程化沙门氏菌菌株,揭示了一种潜在的独特机制。具体而言,白细胞介素-10受体(IL-10R)表达的迟滞非线性特征促使肿瘤浸润的免疫细胞进入肿瘤特异性的IL-10R状态。细菌利用这一点增强肿瘤相关巨噬细胞产生IL-10,逃避肿瘤相关中性粒细胞的吞噬作用,同时扩增并激活原本就存在的衰竭的肿瘤驻留CD8 T细胞。这种有效的组合能够消除肿瘤,防止复发,并抑制多种肿瘤的转移。对人类样本的分析表明,IL-10R状态可能是人类多种肿瘤的普遍特征。本研究揭示了细菌免疫疗法在实体瘤治疗中所面临双重挑战背后的未解机制,并为肿瘤内免疫调节提供了一个框架。
『总结』 本研究发现细菌通过利用IL-10R表达的迟滞非线性特征,在肿瘤微环境中刺激抗肿瘤免疫反应,揭示了细菌免疫疗法抗癌的新机制。
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『Abstract』Coronary arteries have a specific branching pattern crucial for oxygenating heart muscle. Among humans, there is natural variation in coronary anatomy with respect to perfusion of the inferior/posterior left heart, which can branch from either the right arterial tree, the left, or both—a phenotype known as coronary dominance. Using angiographic data for >60,000 US veterans of diverse ancestry, we conducted a genome-wide association study of coronary dominance, revealing moderate heritability and identifying ten significant loci. The strongest association occurred near CXCL12 in both European- and African-ancestry cohorts, with downstream analyses implicating effects on CXCL12 expression. We show that CXCL12 is expressed in human fetal hearts at the time dominance is established. Reducing Cxcl12 in mice altered coronary dominance and caused septal arteries to develop away from Cxcl12 expression domains. These findings indicate that CXCL12 patterns human coronary arteries, paving the way for “medical revascularization” through targeting developmental pathways.

『摘要』 冠状动脉具有特定的分支模式,对心肌供氧至关重要。在人类中,冠状动脉解剖结构在下/后左心室灌注方面存在自然差异,这些动脉可以来自右动脉树、左动脉树或两者——这种表型称为冠状动脉优势。我们利用6万多名不同血统美国退伍军人的血管造影数据,对冠状动脉优势进行了一项全基因组关联研究,揭示了其适度的遗传性,并确定了10个显著性位点。在欧洲血统和非洲血统队列中,最强关联均出现在CXCL12附近,下游分析表明这对CXCL12的表达有影响。我们发现,在冠状动脉优势形成时,CXCL12在人类胎儿心脏中表达。在小鼠中降低Cxcl12的表达会改变冠状动脉优势,并导致室间隔动脉远离Cxcl12表达域发育。这些发现表明,CXCL12决定了人类冠状动脉的走向,为通过靶向发育途径实现“医学再血管化”铺平了道路。
『总结』 研究发现CXCL12影响人类冠状动脉分支模式,或有助于通过发育途径实现医学再血管化。
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『Abstract』Bifidobacteria represent a dominant constituent of human gut microbiomes during infancy, influencing nutrition, immune development, and resistance to infection. Despite interest in bifidobacteria as a live biotic therapy, our understanding of colonization, host-microbe interactions, and the health-promoting effects of bifidobacteria is limited. To address these major knowledge gaps, we used a large-scale genetic approach to create a mutant fitness compendium in Bifidobacterium breve . First, we generated a high-density randomly barcoded transposon insertion pool and used it to determine fitness requirements during colonization of germ-free mice and chickens with multiple diets and in response to hundreds of in vitro perturbations. Second, to enable mechanistic investigation, we constructed an ordered collection of insertion strains covering 1,462 genes. We leveraged these tools to reveal community- and diet-specific requirements for colonization and to connect the production of immunomodulatory molecules to growth benefits. These resources will catalyze future investigations of this important beneficial microbe.

『摘要』 双歧杆菌是婴儿期人类肠道微生物组的主要组成部分,对营养、免疫发育和抗感染能力均有影响。尽管双歧杆菌作为一种活生物治疗方法备受关注,但我们对双歧杆菌的定植、宿主-微生物相互作用以及其促进健康的作用了解有限。为填补这些重大的知识空白,我们采用大规模遗传方法创建了短双歧杆菌突变体适应性综合集。首先,我们生成了一个高密度随机条形码转座子插入库,并利用该库确定了在无菌小鼠和采用多种饲养方式的鸡体内定植过程中,以及在数百种体外扰动下的适应性需求。其次,为进行机制研究,我们构建了包含1462个基因的插入菌株有序集合。我们利用这些工具揭示了定植的群落特异性和饲养方式特异性需求,并将免疫调节分子的产生与生长益处联系起来。这些资源将促进未来对这种重要有益微生物的研究。
『总结』 本研究通过大规模遗传方法创建了短双歧杆菌突变体适应性综合集,揭示了其定植的特定需求及免疫调节分子与生长益处之间的联系,为未来相关研究提供了重要资源。
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『Abstract』The genetic information stored in mRNAs is decoded by ribosomes during mRNA translation. mRNAs are typically translated by multiple ribosomes simultaneously, but it is unclear whether and how the activity of different ribosomes on an mRNA is coordinated. Here, we develop an imaging approach based on stopless-ORF circular RNAs (socRNAs) to monitor translation of individual ribosomes in either monosomes or polysomes with very high resolution. Using experiments and simulations, we find that translating ribosomes frequently undergo transient collisions. However, unlike persistent collisions, such transient collisions escape detection by cellular quality control pathways. Rather, transient ribosome collisions promote productive translation by reducing ribosome pausing on problematic sequences, a process we term ribosome cooperativity. Ribosome cooperativity also reduces recycling of ribosomes by quality control pathways, thus enhancing processive translation. Together, our single-ribosome imaging approach reveals that ribosomes cooperate during translation to ensure fast and efficient translation.

『摘要』 在mRNA翻译过程中,核糖体解码mRNA中存储的遗传信息。通常,多个核糖体会同时翻译同一条mRNA,但尚不清楚不同核糖体在mRNA上的活动是否以及如何协调。本研究开发了一种基于无终止密码子开放阅读框环状RNA(socRNA)的成像方法,能够以非常高的分辨率监测单体或多聚体中单个核糖体的翻译情况。通过实验和模拟,我们发现翻译中的核糖体经常发生短暂碰撞。然而,与持续性碰撞不同,此类短暂碰撞能逃避细胞质量控制途径的检测。相反,核糖体的短暂碰撞能通过减少核糖体在问题序列上的暂停来促进有效翻译,我们将这一过程称为核糖体协同作用。核糖体协同作用还减少了质量控制途径对核糖体的回收,从而增强了连续翻译。综上所述,我们的单核糖体成像方法揭示,核糖体在翻译过程中相互协作,以确保快速高效的翻译。
『总结』 本研究发现翻译中的核糖体会发生短暂碰撞,这种协同作用促进了快速高效的翻译,且能逃避细胞质量控制途径的检测。
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