前沿速递 | NCS 集萃: 2025-02-06 期 [Up]

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『Abstract』Optical frequency combs have enabled distinct advantages in broadband, high-resolution spectroscopy and precision interferometry. However, quantum mechanics ultimately limits the metrological precision achievable with laser frequency combs. Quantum squeezing has led to substantial measurement improvements with continuous wave lasers, but experiments demonstrating metrological advantage with squeezed combs are less developed. Using the Kerr effect in nonlinear optical fiber, a 1-gigahertz frequency comb centered at 1560 nanometers is amplitude-squeezed by >3 decibels (dB) over a 2.5-terahertz bandwidth. Dual-comb interferometry yields mode-resolved spectroscopy of hydrogen sulfide gas with a signal-to-noise ratio nearly 3 dB beyond the shot-noise limit. The quantum noise reduction leads to a twofold quantum speedup in the determination of gas concentration, with implications for high-speed measurements of multiple species in dynamic chemical environments.

『摘要』 光学频率梳在宽带、高分辨率光谱学和精密干涉测量领域带来了显著优势。然而,量子力学从根本上限制了激光频率梳所能达到的测量精度。量子压缩技术已使连续波激光器的测量精度得到了大幅提升,但展示压缩频率梳在计量上优势的实验还较少。利用非线性光纤中的克尔效应,我们使一个中心波长为1560纳米、频率为1吉赫兹的频率梳在2.5太赫兹带宽内实现了幅度压缩,压缩度超过3分贝(dB)。双梳干涉测量技术提供了硫化氢气体的模分辨光谱,其信噪比超过了散粒噪声极限近3dB。量子噪声的减少使气体浓度测定实现了两倍的量子加速,这对动态化学环境中多种物质的高速测量具有重要意义。
『总结』 研究利用克尔效应实现了频率梳的量子压缩,进而在双梳干涉测量中提高了光谱测量的信噪比和速度。
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『Abstract』Kidney dysfunction is a major cause of mortality, but its genetic architecture remains elusive. In this study, we conducted a multiancestry genome-wide association study in 2.2 million individuals and identified 1026 (97 previously unknown) independent loci. Ancestry-specific analysis indicated an attenuation of newly identified signals on common variants in European ancestry populations and the power of population diversity for further discoveries. We defined genotype effects on allele-specific gene expression and regulatory circuitries in more than 700 human kidneys and 237,000 cells. We found 1363 coding variants disrupting 782 genes, with 601 genes also targeted by regulatory variants and convergence in 161 genes. Integrating 32 types of genetic information, we present the “Kidney Disease Genetic Scorecard” for prioritizing potentially causal genes, cell types, and druggable targets for kidney disease.

『摘要』 肾功能障碍是死亡的主要原因之一,但其遗传机制仍不明确。在本研究中,我们对220万人进行了多族群全基因组关联研究,确定了1026个独立基因位点(其中97个为新发现)。族群特异性分析表明,新发现的欧洲血统人群常见变异信号有所减弱,并显示了族群多样性对进一步研究的助力。我们在700多个人类肾脏和23.7万个细胞中定义了基因型对等位基因特异性基因表达和调控回路的影响。我们发现了1363个导致782个基因异常的编码变异,其中601个基因也是调控变异的靶点,161个基因出现聚合现象。通过整合32种遗传信息,我们提出了“肾脏疾病遗传记分卡”,用于优先排序可能导致肾脏疾病的基因、细胞类型和可药物靶点。
『总结』 本研究通过多族群全基因组关联研究确定了多个与肾功能障碍相关的基因位点,并提出了“肾脏疾病遗传记分卡”,以助力肾脏疾病的研究和治疗。
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『Abstract』Exhausted T cells (TEX) in cancer and chronic viral infections undergo metabolic and epigenetic remodeling, impairing their protective capabilities. However, the impact of nutrient metabolism on epigenetic modifications that control TEX differentiation remains unclear. We showed that TEX cells shifted from acetate to citrate metabolism by down-regulating acetyl-CoA synthetase 2 (ACSS2) while maintaining ATP-citrate lyase (ACLY) activity. This metabolic switch increased citrate-dependent histone acetylation, mediated by histone acetyltransferase KAT2A-ACLY interactions, at TEX signature genes while reducing acetate-dependent histone acetylation, dependent on p300-ACSS2 complexes, at effector and memory T cell genes. Nuclear ACSS2 overexpression or ACLY inhibition prevented TEX differentiation and enhanced tumor-specific T cell responses. These findings unveiled a nutrient-instructed histone code governing CD8 T cell differentiation, with implications for metabolic- and epigenetic-based T cell therapies.

『摘要』 在癌症和慢性病毒感染中,衰竭T细胞(TEX)会发生代谢和表观遗传重塑,从而损害其保护能力。然而,营养代谢对控制TEX分化的表观遗传修饰的影响尚不清楚。本研究发现,TEX细胞通过下调乙酰辅酶A合成酶2(ACSS2)同时保持ATP-柠檬酸裂解酶(ACLY)活性,从乙酸代谢转向柠檬酸代谢。这种代谢转变增加了TEX特征基因上由组蛋白乙酰转移酶KAT2A-ACLY相互作用介导的柠檬酸依赖性组蛋白乙酰化,同时减少了效应T细胞和记忆T细胞基因上由p300-ACSS2复合物介导的乙酸依赖性组蛋白乙酰化。核内ACSS2过表达或ACLY抑制可阻止TEX分化,并增强肿瘤特异性T细胞反应。这些发现揭示了一种营养指导的组蛋白密码调控CD8 T细胞分化,对基于代谢和表观遗传的T细胞治疗具有重要意义。
『总结』 本研究发现TEX细胞的代谢转变影响组蛋白乙酰化修饰,进而调控CD8 T细胞分化,为T细胞治疗提供了新的思路。
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『Abstract』In eukaryotes, DNA-associated protein complexes coevolve with genomic sequences to orchestrate chromatin folding. We investigate the relationship between DNA sequence and the spontaneous loading and activity of chromatin components in the absence of coevolution. Using bacterial genomes integrated into Saccharomyces cerevisiae , which diverged from yeast more than 2 billion years ago, we show that nucleosomes, cohesins, and associated transcriptional machinery can lead to the formation of two different chromatin archetypes, one transcribed and the other silent, independently of heterochromatin formation. These two archetypes also form on eukaryotic exogenous sequences, depend on sequence composition, and can be predicted using neural networks trained on the native genome. They do not mix in the nucleus, leading to a bipartite nuclear compartmentalization, reminiscent of the organization of vertebrate nuclei.

『摘要』 在真核生物中,DNA相关蛋白复合物与基因组序列协同进化,共同调控染色质折叠。我们研究了在没有协同进化的情况下,DNA序列与染色质组分自发装载和活性之间的关系。利用20多亿年前就与酵母分化的、整合到酿酒酵母中的细菌基因组,我们发现核小体、黏连蛋白和相关转录机制可以导致两种不同染色质原型的形成,一种是转录活跃的,另一种是转录沉默的,且这一过程不依赖于异染色质的形成。这两种原型也在真核生物的外源序列上形成,依赖于序列组成,并且可以使用在天然基因组上训练的神经网络进行预测。它们在细胞核中不混合,导致细胞核形成二分区室化,类似于脊椎动物细胞核的组织结构。
『总结』 研究发现,即使没有协同进化,DNA序列也能决定染色质组分的自发装载和活性,形成两种不同的染色质原型,并导致细胞核的二分区室化。
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『Abstract』Fast instinctive responses to environmental stimuli can be crucial for survival but are not always optimal. Animals can adapt their behavior and suppress instinctive reactions, but the neural pathways mediating such ethologically relevant forms of learning remain unclear. We found that posterolateral higher visual areas (plHVAs) are crucial for learning to suppress escapes from innate visual threats through a top-down pathway to the ventrolateral geniculate nucleus (vLGN). plHVAs are no longer necessary after learning; instead, the learned behavior relies on plasticity within vLGN populations that exert inhibitory control over escape responses. vLGN neurons receiving input from plHVAs enhance their responses to visual threat stimuli during learning through endocannabinoid-mediated long-term suppression of their inhibitory inputs. We thus reveal the detailed circuit, cellular, and synaptic mechanisms underlying experience-dependent suppression of fear responses.

『摘要』 对环境刺激的快速本能反应对生存至关重要,但并不总是最优选择。动物能够适应其行为并抑制本能反应,但介导这种与生态学相关的学习形式的神经通路仍不明确。我们发现,后外侧高位视觉区(plHVAs)对于通过学习抑制由先天视觉威胁引发的逃避反应至关重要,这一过程是通过一条至腹外侧膝状体核(vLGN)的自上而下通路实现的。学习完成后,plHVAs便不再必要;相反,习得行为依赖于对逃避反应发挥抑制性控制的vLGN神经元群体的可塑性。在学习过程中,接收来自plHVAs输入的vLGN神经元通过内源性大麻素介导的长期抑制其抑制性输入,增强了对视觉威胁刺激的反应。因此,我们揭示了经验依赖性恐惧反应抑制的详细环路、细胞和突触机制。
『总结』 研究发现后外侧高位视觉区通过学习抑制逃避反应,揭示了与生态学相关学习的神经机制。
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『Abstract』Humpback whale song is a culturally transmitted behavior. Human language, which is also culturally transmitted, has statistically coherent parts whose frequency distribution follows a power law. These properties facilitate learning and may therefore arise because of their contribution to the faithful transmission of language over multiple cultural generations. If so, we would expect to find them in other culturally transmitted systems. In this study, we applied methods based on infant speech segmentation to 8 years of humpback recordings, uncovering in whale song the same statistical structure that is a hallmark of human language. This commonality, in two evolutionarily distant species, points to the role of learning and cultural transmission in the emergence of properties thought to be unique to human language.

『摘要』 座头鲸的歌声是一种通过文化传承的行为。人类语言同样是通过文化传承的,其具有统计上一致的部分,这些部分的频率分布遵循幂律。这些特性有助于语言学习,并可能因此有助于语言在多个文化代际中忠实传承而逐渐产生。如果确实如此,我们有望在其他通过文化传承的系统中发现它们。在本研究中,我们对8年的座头鲸录音应用了基于婴儿语音分割的方法,发现鲸歌中具有与人类语言标志相同的统计结构。这两个进化上相距甚远的物种之间的这一共性,指出了学习和文化传承在出现那些曾被认为人类语言所独有的特性时所起的作用。
『总结』 研究发现座头鲸歌声和人类语言具有相同的统计结构,表明学习和文化传承在这些特性的出现中发挥了重要作用。
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『Abstract』According to Noether’s theorem, symmetries in a physical system are intertwined with conserved quantities. These symmetries often determine the system topology, which is made ever more complex with increased dimensionality. Quasicrystals have neither translational nor global rotational symmetry, yet they intrinsically inhabit a higher-dimensional space in which symmetry resurfaces. Here, we discovered topological charge vectors in four dimensions (4D) that govern the real-space topology of 2D quasicrystals and reveal their inherent conservation laws. We demonstrate control over the topology in pentagonal plasmonic quasilattices, mapped by both phase-resolved and time-domain near-field microscopy, showing that their temporal evolution continuously tunes the 2D projections of their distinct 4D topologies. Our work provides a route to experimentally probe the thermodynamic properties of quasicrystals and topological physics in 4D and above.

『摘要』 根据诺特定理,物理系统中的对称性与守恒量相互关联。这些对称性通常决定了系统拓扑,而系统拓扑会随着维度的增加而愈发复杂。准晶体既没有平移对称性,也没有全局旋转对称性,但它们本质上存在于一个更高维度的空间中,在该空间中对称性会重新出现。本研究发现了四维(4D)拓扑电荷矢量,这些矢量控制着二维(2D)准晶体的实空间拓扑,并揭示了其固有的守恒定律。我们通过相分辨和时间域近场显微镜对五边形等离激元准晶格中的拓扑进行了表征,结果表明,其时间演化能够连续调节其独特4D拓扑的2D投影。本研究为实验探索准晶体的热力学特性以及四维及以上空间的拓扑物理提供了一条途径。
『总结』 本研究发现了控制2D准晶体实空间拓扑的4D拓扑电荷矢量,并展示了通过时间演化调节其2D投影的方法,为探索高维拓扑物理提供了新途径。
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『Abstract』In many species with sex chromosomes, the Y is a tiny chromosome. However, the dioecious plant Silene latifolia has a giant ~550-megabase Y chromosome, which has remained unsequenced so far. We used a long- and short-read hybrid approach to obtain a high-quality male genome. Comparative analysis of the sex chromosomes with their homologs in outgroups showed that the Y is highly rearranged and degenerated. Recombination suppression between X and Y extended in several steps and triggered a massive accumulation of repeats on the Y as well as in the nonrecombining pericentromeric region of the X, leading to giant sex chromosomes. Using sex phenotype mutants, we identified candidate sex-determining genes on the Y in locations consistent with their favoring recombination suppression events 11 and 5 million years ago.

『摘要』 在许多具有性染色体的物种中,Y染色体是一条微小的染色体。然而,雌雄异体的植物长柱玄参却拥有一条巨大的、约5.5亿碱基的Y染色体,该染色体迄今为止尚未被测序。我们采用长短读长混合的方法获得了高质量的雄性基因组。性染色体与其外类群同源染色体的比较分析表明,Y染色体发生了高度重组和退化。X染色体和Y染色体之间的重组抑制是分几个步骤进行的,并引发了Y染色体以及X染色体非重组的着丝粒周围区域大量重复序列的积累,从而形成了巨大的性染色体。利用性表型突变体,我们在Y染色体上确定了候选的性别决定基因,其位置与1100万年和500万年前有利于重组抑制事件的位置一致。
『总结』 研究发现长柱玄参拥有巨大的Y染色体,该染色体经历了高度重组和退化,且X和Y染色体间的重组抑制导致了大量重复序列积累,研究还确定了Y染色体上与重组抑制事件一致的性别决定基因候选位置。
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『Abstract』Insulin resistance is a hallmark of obesity-associated type 2 diabetes. Insulin’s actions go beyond metabolic cells and also involve blood vessels, where insulin increases capillary blood flow and delivery of insulin and nutrients. We show that adrenomedullin, whose plasma levels are increased in obese humans and mice, inhibited insulin signaling in human endothelial cells through protein-tyrosine phosphatase 1B–mediated dephosphorylation of the insulin receptor. In obese mice lacking the endothelial adrenomedullin receptor, insulin-induced endothelial nitric oxide–synthase activation and skeletal muscle perfusion were increased. Treating mice with adrenomedullin mimicked the effect of obesity and induced endothelial and systemic insulin resistance. Endothelial loss or blockade of the adrenomedullin receptor improved obesity-induced insulin resistance. These findings identify a mechanism underlying obesity-induced systemic insulin resistance and suggest approaches to treat obesity-associated type 2 diabetes.

『摘要』 胰岛素抵抗是肥胖相关2型糖尿病的标志。胰岛素的作用不仅限于代谢细胞,还涉及血管,胰岛素可增加毛细血管血流,促进胰岛素和营养物质的输送。我们发现,肾上腺髓质素在肥胖人群和小鼠的血浆水平有所升高,其通过蛋白酪氨酸磷酸酶1B介导的胰岛素受体去磷酸化作用,抑制了人内皮细胞中的胰岛素信号传导。在缺乏内皮肾上腺髓质素受体的肥胖小鼠中,胰岛素诱导的内皮型一氧化氮合酶活化和骨骼肌灌注增加。对小鼠给予肾上腺髓质素可模拟肥胖效应并诱导内皮和全身胰岛素抵抗。内皮肾上腺髓质素受体的丧失或阻断可改善肥胖诱导的胰岛素抵抗。这些发现揭示了肥胖诱导全身胰岛素抵抗的机制,并为治疗肥胖相关2型糖尿病提供了方法。
『总结』 研究发现肾上腺髓质素通过影响内皮细胞中的胰岛素信号传导导致胰岛素抵抗,为肥胖相关2型糖尿病治疗提供了新思路。
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『Abstract』Measures to combat the parasites that cause malaria have become compromised because of reliance on a small arsenal of drugs and emerging drug resistance. We conducted a transposon mutagenesis screen in the primate malaria parasite Plasmodium knowlesi , producing the most complete classification of gene essentiality in any Plasmodium spp. to date, with the resolution to define truncatable genes. We found conservation in the druggable genome between Plasmodium spp. and divergences in mitochondrial metabolism. Perturbation analyses with the frontline antimalarial artemisinin revealed modulators that both increase and decrease drug susceptibility. Our findings aid prioritization of drug and vaccine targets for the Plasmodium vivax clade and reveal mechanisms of resistance that can inform therapeutic development.

『摘要』 为对抗引发疟疾的寄生虫而采取的措施,由于药物种类有限以及药物耐药性不断出现而面临挑战。我们在灵长类疟原虫——诺氏疟原虫中进行了转座子突变筛选,得出了迄今为止任何疟原虫中最完整的基因必要性分类,并能够确定可截短的基因。我们发现疟原虫之间在可药物基因组上存在保守性,而在线粒体代谢上存在差异性。利用一线抗疟药物青蒿素进行的扰动分析,发现了可增加和降低药物敏感性的调节因子。我们的研究结果有助于确定间日疟原虫族的药物和疫苗靶点优先级,并揭示了可指导治疗药物开发的耐药机制。
『总结』 本研究通过对诺氏疟原虫进行转座子突变筛选,揭示了疟原虫的基因必要性分类、药物基因组的保守性和线粒体代谢的差异性,并发现了影响青蒿素敏感性的调节因子,为疟疾治疗药物和疫苗的研发提供了新思路。
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『Abstract』Malaria parasites are highly divergent from model eukaryotes. Large-scale genome engineering methods effective in model organisms are frequently inapplicable, and systematic studies of gene function are few. We generated more than 175,000 transposon insertions in the Plasmodium knowlesi genome, averaging an insertion every 138 base pairs, and used this “supersaturation” mutagenesis to score essentiality for 98% of genes. The density of mutations allowed mapping of putative essential domains within genes, providing a completely new level of genome annotation for any Plasmodium species. Although gene essentiality was largely conserved across P. knowlesi , Plasmodium falciparum , and rodent malaria model Plasmodium berghei , a large number of shared genes are differentially essential, revealing species-specific adaptations. Our results indicated that Plasmodium essential gene evolution was conditionally linked to adaptive rewiring of metabolic networks for different hosts.

『摘要』 疟原虫与模式真核生物存在很大差异。在模式生物中有效的大规模基因组工程方法往往不适用于疟原虫,且对其基因功能进行系统研究的也很少。我们在诺氏疟原虫(Plasmodium knowlesi)基因组中生成了超过17.5万个转座子插入位点,平均每138个碱基对就有一个插入位点,并利用这种“超饱和”诱变技术评估了98%基因的重要性。突变的密度使得我们能够在基因内绘制出推测的必要结构域,为任何疟原虫物种提供了全新的基因组注释水平。尽管基因的重要性在诺氏疟原虫、恶性疟原虫(Plasmodium falciparum)和小鼠疟疾模型伯氏疟原虫(Plasmodium berghei)之间大致保守,但大量共有基因的重要性存在差异,揭示了物种特异性适应。我们的研究结果表明,疟原虫必需基因的进化与不同宿主代谢网络的适应性重连有条件关联。
『总结』 该研究利用超饱和诱变技术评估了诺氏疟原虫基因的重要性,并揭示了疟原虫物种特异性适应和代谢网络适应性重连的关联。
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『Abstract』Some plants have massive sex-linked regions. To test hypotheses about their evolution, we sequenced the genome of Silene latifolia , in which giant heteromorphic sex chromosomes were first discovered in 1923. It has long been known that the Y chromosome consists mainly of a male-specific region that does not recombine with the X chromosome and carries the sex-determining genes and genes with other male functions. However, only with a whole Y chromosome assembly can candidate genes be validated experimentally and their locations determined and related to the suppression of recombination. We describe the genomic changes as the ancestral chromosome evolved into the current XY pair, testing ideas about the evolution of large nonrecombining regions and the mechanisms that created the present recombination pattern.

『摘要』 一些植物具有巨大的性连锁区域。为验证有关其进化的假设,我们对1923年首次发现巨大异型性染色体的白穗花基因组进行了测序。人们早就知道,Y染色体主要由一个不与X染色体重组的雄性特异区域组成,该区域携带决定性别的基因和其他具有雄性功能的基因。但是,只有完成整个Y染色体的组装,才能通过实验验证候选基因,并确定其位置以及与重组抑制的关系。我们描述了祖先染色体进化成当前XY对时所发生的基因组变化,验证了关于大型非重组区域进化的观点以及形成当前重组模式的机制。
『总结』 本研究通过对白穗花进行基因组测序,揭示了其性染色体的进化历程,验证了大型非重组区域的形成机制,并确定了与重组抑制相关的基因位置。
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『Abstract』The powerful strikes generated by the smasher mantis shrimp require it to possess a robust protection mechanism to withstand the resultant forces. Although recent studies have suggested that phononic bandgaps complement the mantis shrimp’s defensive suite, direct experimental evidence for this mechanism has remained elusive. In this work, we explored the phononic properties of the mantis shrimp’s dactyl club using laser ultrasonic techniques and numerical simulations. Our results demonstrate that the dactyl club’s periodic region functions as a dispersive, high-quality graded system, exhibiting Bloch harmonics, flat dispersion branches, ultraslow wave modes, and wide Bragg bandgaps in the lower megahertz range. These features effectively shield the shrimp from harmful high-frequency stress waves generated by cavitation bubble collapse events during impact.

『摘要』 螳螂虾产生的强大打击力要求其必须拥有强大的保护机制来承受由此产生的力量。尽管最近的研究表明,声子带隙补充了螳螂虾的防御系统,但这一机制的直接实验证据仍然难以捉摸。在本研究中,我们使用激光超声技术和数值模拟探索了螳螂虾指节棍的声子特性。我们的研究结果表明,指节棍的周期区域作为一个分散的、高质量的梯度系统,在下兆赫兹范围内表现出布洛赫谐波、平坦的色散分支、超慢波模式和宽布拉格带隙。这些特性有效地保护了螳螂虾免受撞击过程中空化气泡坍塌事件产生的高频有害应力波的伤害。
『总结』 研究发现螳螂虾指节棍具有特殊的声子特性,能有效屏蔽撞击产生的高频有害应力波。
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『Abstract』Plants grow complex root systems to extract unevenly distributed resources from soils. Spatial differences in soil moisture are perceived by root tips, leading to the patterning of new root branches toward available water in a process called hydropatterning. Little is known about hydropatterning behavior and its genetic basis in crop plants. Here, we developed an assay to measure hydropatterning in maize and revealed substantial differences between tropical/subtropical and temperate maize breeding germplasm that likely resulted from divergent selection. Genetic analysis of hydropatterning confirmed the regulatory role of auxin and revealed that the gaseous hormone ethylene locally inhibits root branching from air-exposed tissues. Our results demonstrate how distinct signaling pathways translate spatial patterns of water availability to developmental programs that determine root architecture.

『摘要』 植物会生长出复杂的根系,以从土壤中汲取分布不均的资源。根尖可以感知土壤水分的空间差异,从而使新的根分支向有水的地方生长,这一过程被称为水分模式诱导的根系分支(简称水分分布诱导)。目前,人们对作物中的水分分布诱导行为及其遗传基础知之甚少。本研究开发了一种测定玉米水分分布诱导的方法,并揭示了热带/亚热带玉米和温带玉米育种种质之间存在的显著差异,这种差异可能是由趋异选择造成的。对水分分布诱导的遗传分析证实了生长素的调控作用,并发现气态激素乙烯会局部抑制暴露于空气中的组织的根分支。本研究结果揭示了不同的信号通路如何将水分的空间分布转化为决定根系结构的发育程序。
『总结』 本研究揭示了玉米根系中水分分布诱导的现象、遗传差异及激素调控机制,为理解根系结构与水分分布的关系提供了新视角。
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『Abstract』Understanding how interacting particles approach thermal equilibrium is a major challenge of quantum simulators . Unlocking the full potential of such systems towards this goal requires flexible initial state preparation, precise time evolution and extensive probes for final state characterization. Here we present a quantum simulator comprising 69 superconducting qubits that supports both universal quantum gates and high-fidelity analogue evolution, with performance beyond the reach of classical simulation in cross-entropy benchmarking experiments. This hybrid platform features more versatile measurement capabilities compared with analogue-only simulators, which we leverage here to reveal a coarsening-induced breakdown of Kibble–Zurek scaling predictions in the XY model, as well as signatures of the classical Kosterlitz–Thouless phase transition . Moreover, the digital gates enable precise energy control, allowing us to study the effects of the eigenstate thermalization hypothesis in targeted parts of the eigenspectrum. We also demonstrate digital preparation of pairwise-entangled dimer states, and image the transport of energy and vorticity during subsequent thermalization in analogue evolution. These results establish the efficacy of superconducting analogue–digital quantum processors for preparing states across many-body spectra and unveiling their thermalization dynamics.

『摘要』 理解相互作用粒子如何接近热平衡是量子模拟器面临的一项主要挑战。为实现这一目标而充分发挥这些系统的潜力,需要灵活的初始状态制备、精确的时间演化和对最终状态特征进行广泛探测。在此,我们展示了一个由69个超导量子比特组成的量子模拟器,该模拟器既支持通用量子门,也支持高保真模拟演化,在交叉熵基准测试中,其性能超越了经典模拟的范围。与仅模拟的模拟器相比,该混合平台具有更多样化的测量能力,我们利用这一平台揭示了XY模型中由粗化引起的基布尔-祖雷克标度预测崩溃,以及经典科斯特利茨-陶勒斯相变的特征。此外,数字门能够实现精确的能量控制,使我们能够在特征谱的目标部分研究本征态热化假设的影响。我们还展示了成对纠缠二聚体状态的数字制备,并成像了在随后的模拟演化过程中能量和涡旋的传输。这些结果证明了超导模拟-数字量子处理器在制备多体谱中的状态和揭示其热化动力学方面的有效性。
『总结』 本研究展示了一个由69个超导量子比特组成的量子模拟器,它结合了通用量子门和高保真模拟演化的优势,能够制备多体谱中的状态并揭示其热化动力学。
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『Abstract』Cellular identity requires the concerted action of multiple transcription factors (TFs) bound together to enhancers of cell-type-specific genes. Despite TFs recognizing specific DNA motifs within accessible chromatin, this information is insufficient to explain how TFs select enhancers . Here we compared four different TF combinations that induce different cell states, analysing TF genome occupancy, chromatin accessibility, nucleosome positioning and 3D genome organization at the nucleosome resolution. We show that motif recognition on mononucleosomes can decipher only the individual binding of TFs. When bound together, TFs act cooperatively or competitively to target nucleosome arrays with defined 3D organization, displaying motifs in particular patterns. In one combination, motif directionality funnels TF combinatorial binding along chromatin loops, before infiltrating laterally to adjacent enhancers. In other combinations, TFs assemble on motif-dense and highly interconnected loop junctions, and subsequently translocate to nearby lineage-specific sites. We propose a guided-search model in which motif grammar on nucleosome fibres acts as signpost elements, directing TF combinatorial binding to enhancers.

『摘要』 细胞身份需要多个转录因子(TF)协同作用,共同结合到细胞类型特异性基因的增强子上。尽管转录因子能够在可接近的染色质内识别特定的DNA基序,但仅凭这些信息还不足以解释转录因子如何选择增强子。在这里,我们比较了四种不同的转录因子组合(可诱导不同的细胞状态),并分析了转录因子的基因组占有率、染色质可及性、核小体定位和核小体分辨率下的三维基因组结构。我们发现,在单核小体上的基序识别只能解析转录因子的单独结合。当转录因子结合在一起时,它们会协同或竞争性地作用于具有特定三维结构的核小体阵列,并以特定模式显示基序。在一种组合中,基序的方向性会引导转录因子组合沿染色质环结合,然后再横向渗透到相邻的增强子。在其他组合中,转录因子会在基序密集且高度互联的环连接处组装,然后转移到附近的谱系特异性位点。我们提出了一个引导搜索模型,其中核小体纤维上的基序语法作为指示元素,指导转录因子组合结合到增强子上。
『总结』 本研究揭示了转录因子通过协同或竞争作用,在具有特定三维结构的核小体阵列上选择增强子的机制,并提出了一个引导搜索模型来解释这一过程。
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『Abstract』Personalized antisense oligonucleotides (ASOs) have achieved positive results in the treatment of rare genetic disease . As clinical sequencing technologies continue to advance, the ability to identify patients with rare disease harbouring pathogenic genetic variants amenable to this therapeutic strategy will probably improve. Here we describe a scalable platform for generating patient-derived cellular models and demonstrate that these personalized models can be used for preclinical evaluation of patient-specific ASOs. We describe protocols for delivery of ASOs to patient-derived organoid models and confirm reversal of disease-associated phenotypes in cardiac organoids derived from a patient with Duchenne muscular dystrophy (DMD) with a structural deletion in the gene encoding dystrophin ( DMD ) that is amenable to treatment with existing ASO therapeutics. Furthermore, we designed novel patient-specific ASOs for two additional patients with DMD (siblings) with a deep intronic variant in the DMD gene that gives rise to a novel splice acceptor site, incorporation of a cryptic exon and premature transcript termination. We showed that treatment of patient-derived cardiac organoids with patient-specific ASOs results in restoration of DMD expression and reversal of disease-associated phenotypes. The approach outlined here provides the foundation for an expedited path towards the design and preclinical evaluation of personalized ASO therapeutics for a broad range of rare diseases.

『摘要』 个性化反义寡核苷酸(ASOs)在治疗罕见遗传病方面已取得积极成果。随着临床测序技术的不断进步,识别出患有可通过这种治疗策略干预的致病性遗传变异罕见病患者的能力可能会得到提高。本文介绍了一个用于生成患者源性细胞模型的可扩展平台,并证明了这些个性化模型可用于患者特异性ASOs的临床前评估。我们描述了向患者源性类器官模型递送ASOs的方案,并证实了在一名杜氏肌营养不良症(DMD)患者的心脏类器官中,疾病相关表型得到了逆转。该患者编码肌营养不良蛋白的基因存在结构性缺失,适合使用现有的ASO治疗药物。此外,我们还为另外两名DMD患者(兄弟姐妹)设计了新型患者特异性ASOs,他们DMD基因中的深度内含子变异导致了一个新的剪接受体位点的产生、一个隐匿外显子的掺入和转录提前终止。我们的研究表明,用患者特异性ASOs治疗患者源性心脏类器官可以恢复DMD的表达并逆转疾病相关表型。本文概述的方法为加快设计针对广泛罕见病的个性化ASO治疗药物及其临床前评估奠定了基础。
『总结』 本文介绍了一种可扩展的患者源性细胞模型平台,通过该平台验证了个性化反义寡核苷酸(ASOs)在临床前评估中的有效性,为罕见病的个性化治疗提供了新途径。
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『Abstract』Asteroid discoveries are essential for planetary-defence efforts aiming to prevent impacts with Earth , including the more frequent megaton explosions from decametre impactors . Although large asteroids (≥100 kilometres) have remained in the main belt since their formation , small asteroids are commonly transported to the near-Earth object (NEO) population . However, owing to the lack of direct observational constraints, their size–frequency distribution (SFD)—which informs our understanding of the NEOs and the delivery of meteorite samples to Earth—varies substantially among models . Here we report 138 detections of some of the smallest asteroids ( ≳ 10 metres) ever observed in the main belt, which were enabled by JWST’s infrared capabilities covering the emission peaks of the asteroids and synthetic tracking techniques . Despite small orbital arcs, we constrain the distances and phase angles of the objects using known asteroids as proxies, allowing us to derive sizes through radiometric techniques. Their SFD shows a break at about 100 metres (debiased cumulative slopes of q = −2.66 ± 0.60 and −0.97 ± 0.14 for diameters smaller and larger than roughly 100 metres, respectively), suggestive of a population driven by collisional cascade. These asteroids were sampled from several asteroid families—most probably Nysa, Polana and Massalia—according to the geometry of pointings considered here. Through further long-stare infrared observations, JWST is poised to serendipitously detect thousands of decametre-scale asteroids across the sky, examining individual asteroid families and the source regions of meteorites ‘in situ’.

『摘要』 小行星的发现对于旨在防止小行星撞击地球的行星防御工作至关重要,其中包括更频繁地发生的由十米级撞击体引发的百万吨级爆炸。虽然大型小行星(直径≥100公里)自形成以来就一直留在主带,但小型小行星通常会被输送到近地天体(NEO)族群中。然而,由于缺乏直接的观测限制,它们的尺寸-频率分布(SFD)在模型之间存在很大差异,而该分布有助于我们了解近地天体和陨石样本到达地球的情况。在此,我们报告了在主带中观测到的138颗有史以来最小的小行星(直径略大于10米)的发现,这是借助詹姆斯·韦伯太空望远镜(JWST)覆盖小行星发射峰的红外能力和综合跟踪技术实现的。尽管这些小行星的轨道弧较小,但我们通过使用已知小行星作为代理,限制了这些天体的距离和相位角,从而能够通过辐射测量技术推导出它们的尺寸。它们的尺寸-频率分布在直径约100米处出现拐点(直径小于和大于约100米的无偏累积斜率分别为q = −2.66 ± 0.60和−0.97 ± 0.14),这表明该族群是由碰撞级联驱动的。根据本文考虑的指向几何形状,这些小行星很可能来自几个小行星族,其中最有可能是尼斯族、波拉纳族和马萨利亚族。通过进一步的长时间红外观测,JWST有望在整个天空中意外发现数千颗十米级小行星,从而能够就地研究单个小行星族和陨石的来源区域。
『总结』 研究人员利用JWST发现了138颗主带中的小型小行星,并通过分析揭示了小行星尺寸-频率分布的特征,有望通过进一步观测研究小行星族和陨石来源。
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『Abstract』Cerebral cortex development in humans is a highly complex and orchestrated process that is under tight genetic regulation. Rare mutations that alter gene expression or function can disrupt the structure of the cerebral cortex, resulting in a range of neurological conditions . Lissencephaly (‘smooth brain’) spectrum disorders comprise a group of rare, genetically heterogeneous congenital brain malformations commonly associated with epilepsy and intellectual disability . However, the molecular mechanisms underlying disease pathogenesis remain unknown. Here we establish hypoactivity of the mTOR pathway as a clinically relevant molecular mechanism in lissencephaly spectrum disorders. We characterized two types of cerebral organoid derived from individuals with genetically distinct lissencephalies with a recessive mutation in p53-induced death domain protein 1 ( PIDD1 ) or a heterozygous chromosome 17p13.3 microdeletion leading to Miller–Dieker lissencephaly syndrome (MDLS). PIDD1-mutant organoids and MDLS organoids recapitulated the thickened cortex typical of human lissencephaly and demonstrated dysregulation of protein translation, metabolism and the mTOR pathway. A brain-selective activator of mTOR complex 1 prevented and reversed cellular and molecular defects in the lissencephaly organoids. Our findings show that a converging molecular mechanism contributes to two genetically distinct lissencephaly spectrum disorders.

『摘要』 人类大脑皮层的发育是一个高度复杂且协调的过程,受到严格的遗传调控。罕见的基因突变会改变基因的表达或功能,从而破坏大脑皮层的结构,导致一系列神经系统疾病。无脑回畸形(“光滑脑”)谱系疾病是一组罕见的、遗传异质性的先天性脑畸形,通常与癫痫和智力障碍相关。然而,该疾病发病的分子机制尚不清楚。本研究发现,mTOR通路的低活性是无脑回畸形谱系疾病中具有临床相关性的分子机制。我们研究了来自具有不同遗传背景的无脑回畸形患者的两种脑类器官,这些患者分别携带p53诱导死亡结构域蛋白1(PIDD1)的隐性突变或导致Miller-Dieker无脑回畸形综合征(MDLS)的17p13.3染色体微缺失杂合子。PIDD1突变的类器官和MDLS类器官均再现了人类无脑回畸形典型的皮层增厚特征,并表现出蛋白质翻译、代谢和mTOR通路的失调。一种选择性作用于大脑的mTOR复合物1激活剂可预防和逆转无脑回畸形类器官中的细胞和分子缺陷。我们的研究结果表明,一种趋同的分子机制导致了两种遗传背景不同的无脑回畸形谱系疾病。
『总结』 研究发现mTOR通路的低活性是两种遗传不同的无脑回畸形疾病的共同分子机制,且一种mTOR激活剂能纠正相关缺陷。
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『Abstract』Freshwater ecosystems are highly biodiverse and important for livelihoods and economic development , but are under substantial stress . To date, comprehensive global assessments of extinction risk have not included any speciose groups primarily living in freshwaters. Consequently, data from predominantly terrestrial tetrapods are used to guide environmental policy and conservation prioritization , whereas recent proposals for target setting in freshwaters use abiotic factors . However, there is evidence that such data are insufficient to represent the needs of freshwater species and achieve biodiversity goals . Here we present the results of a multi-taxon global freshwater fauna assessment for The IUCN Red List of Threatened Species covering 23,496 decapod crustaceans, fishes and odonates, finding that one-quarter are threatened with extinction. Prevalent threats include pollution, dams and water extraction, agriculture and invasive species, with overharvesting also driving extinctions. We also examined the degree of surrogacy of both threatened tetrapods and freshwater abiotic factors (water stress and nitrogen) for threatened freshwater species. Threatened tetrapods are good surrogates when prioritizing sites to maximize rarity-weighted richness, but poorer when prioritizing based on the most range-restricted species. However, they are much better surrogates than abiotic factors, which perform worse than random. Thus, although global priority regions identified for tetrapod conservation are broadly reflective of those for freshwater faunas, given differences in key threats and habitats, meeting the needs of tetrapods cannot be assumed sufficient to conserve freshwater species at local scales.

『摘要』 淡水生态系统生物多样性极为丰富,对人类的生计和经济发展至关重要,但目前正承受着巨大压力。迄今为止,全面的全球灭绝风险评估尚未包括任何主要生活在淡水中的物种丰富类群。因此,指导环境政策和保护优先事项的数据主要来自陆生四足动物,而最近关于淡水目标设定的提案则使用了非生物因素。然而,有证据表明,这些数据不足以代表淡水物种的需求和实现生物多样性目标。本文介绍了世界自然保护联盟(IUCN)濒危物种红色名录多分类群全球淡水动物评估的结果,该评估涵盖了23496种十足目甲壳动物、鱼类和蜻蜓目昆虫,结果发现其中四分之一正面临灭绝威胁。普遍的威胁包括污染、水坝和水资源开采、农业以及外来入侵物种,过度捕捞也是导致物种灭绝的一个驱动因素。本文还研究了受威胁四足动物和淡水非生物因素(水资源压力和氮)对受威胁淡水物种的替代程度。在优先考虑地点以最大化稀有度加权丰富度时,受威胁四足动物是很好的替代指标,但在基于分布范围最受限的物种进行优先排序时,其表现则较差。然而,与非生物因素相比,四足动物作为替代指标的表现要好得多,因为非生物因素的表现甚至不如随机选择。因此,尽管为全球四足动物保护确定的优先区域大体上也能反映出淡水动物类群的优先区域,但鉴于主要威胁和栖息地的差异,满足四足动物的需求并不能假定就足以在地方尺度上保护淡水物种。
『总结』 全球淡水生态系统面临多重威胁,新的评估显示四分之一的淡水动物物种面临灭绝风险,且四足动物作为保护优先事项的替代指标存在局限性,因此需要针对淡水物种制定更具体的保护措施。
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『Abstract』Fossils representing Cretaceous lineages of crown clade birds (Aves) are exceptionally rare but are crucial to elucidating major ecological shifts across early avian divergences. Among the earliest known putative crown birds is Vegavis iaai , a foot-propelled diver from the latest Cretaceous (69.2–68.4 million years ago) of Antarctica with controversial phylogenetic affinities . Initially recovered by phylogenetic analyses as a stem anatid (ducks and closely related species) , Vegavis has since been recovered as a stem member of Anseriformes (waterfowl) , or outside Aves altogether . Here we report a new, nearly complete skull of Vegavis that provides new insight into its feeding ecology and exhibits morphologies that support placement among waterfowl within crown-group birds. Vegavis has an avian beak (absence of teeth and reduced maxilla) and brain shape (hyperinflated cerebrum and ventrally shifted optic lobes). The temporal fossa is well excavated and expansive, indicating that this bird had hypertrophied jaw musculature. The beak is narrow and pointed, and the mandible lacks retroarticular processes. Together, these features comprise a feeding apparatus unlike that of any other known anseriform but like that of other extant birds that capture prey underwater (for example, grebes and loons). The Cretaceous occurrence of Vegavis , with a feeding ecology unique among known Galloanserae (waterfowl and landfowl), is further indication that the earliest anseriform divergences were marked by evolutionary experiments unrepresented in the extant diversity .

『摘要』 白垩纪冠群鸟类(鸟纲)的化石极为罕见,但对于阐明早期鸟类分化过程中的重大生态转变至关重要。已知最早的冠群鸟类之一是Vegavis iaai,它是一种来自南极洲白垩纪末期(6920万至6840万年前)的足动潜水鸟,但其系统发育亲缘关系一直存在争议。最初,系统发育分析将其归为雁形目(鸭类及其近亲)的干群成员,但后来的研究又将其归为雁形目的干群成员,或者完全不属于鸟纲。本文报告了一具Vegavis的新近完整颅骨,该颅骨为我们提供了关于其摄食生态的新见解,并展现出支持其属于冠群鸟类中雁形目的形态特征。Vegavis具有鸟类喙(无牙齿,上颌骨退化)和脑形(大脑极度膨胀,视叶向下移位)。其颞窝深且宽,表明这种鸟的颌肌发达。喙狭窄且尖锐,下颌缺乏后关节突。这些特征共同构成了一种捕食装置,不同于已知的任何其他雁形目鸟类,但与其他在水下捕食猎物的现存鸟类(如䴙䴘和潜鸟)相似。Vegavis出现在白垩纪,其摄食生态在已知的鸡雁小纲(水禽和陆禽)中独一无二,这进一步表明,最早的雁形目分化以现存多样性中未体现的进化试验为特征。
『总结』 新发现的Vegavis颅骨化石提供了关于其独特摄食生态和雁形目分类的新证据,揭示了早期鸟类分化中的进化实验。
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『Abstract』Plants lack specialized and mobile immune cells. Consequently, any cell type that encounters pathogens must mount immune responses and communicate with surrounding cells for successful defence. However, the diversity, spatial organization and function of cellular immune states in pathogen-infected plants are poorly understood . Here we infect Arabidopsis thaliana leaves with bacterial pathogens that trigger or supress immune responses and integrate time-resolved single-cell transcriptomic, epigenomic and spatial transcriptomic data to identify cell states. We describe cell-state-specific gene-regulatory logic that involves transcription factors, putative cis -regulatory elements and target genes associated with disease and immunity. We show that a rare cell population emerges at the nexus of immune-active hotspots, which we designate as primary immune responder (PRIMER) cells. PRIMER cells have non-canonical immune signatures, exemplified by the expression and genome accessibility of a previously uncharacterized transcription factor, GT-3A, which contributes to plant immunity against bacterial pathogens. PRIMER cells are surrounded by another cell state (bystander) that activates genes for long-distance cell-to-cell immune signalling. Together, our findings suggest that interactions between these cell states propagate immune responses across the leaf. Our molecularly defined single-cell spatiotemporal atlas provides functional and regulatory insights into immune cell states in plants.

『摘要』 植物缺乏专门且可移动的免疫细胞。因此,任何遇到病原体的细胞类型都必须产生免疫反应并与周围细胞进行通信以成功防御。然而,目前对于病原体感染的植物中细胞免疫状态的多样性、空间组织和功能还知之甚少。在本研究中,我们用触发或抑制免疫反应的细菌病原体感染拟南芥叶片,并整合了时间分辨的单细胞转录组、表观基因组和空间转录组数据来识别细胞状态。我们描述了细胞状态特异性基因调控逻辑,涉及与疾病和免疫相关的转录因子、假定的顺式调控元件和目标基因。我们发现,在免疫活跃热点交汇处出现了一种罕见的细胞群体,我们将其命名为初级免疫应答细胞(PRIMER)。PRIMER细胞具有非经典的免疫特征,例如一种先前未表征的转录因子GT-3A的表达和基因组可及性,该转录因子有助于植物对细菌病原体的免疫。PRIMER细胞周围是另一种细胞状态(旁观者),可激活远距离细胞间免疫信号传导的基因。综上所述,我们的研究结果表明,这些细胞状态之间的相互作用促进了整个叶片的免疫反应传播。我们分子定义的单细胞时空图谱为植物免疫细胞状态提供了功能和调控方面的见解。
『总结』 本研究揭示了植物中细胞免疫状态的多样性、空间组织和功能特征,并发现了一种新的罕见细胞群体——初级免疫应答细胞(PRIMER),其在植物免疫反应中发挥着关键作用。
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『Abstract』A particle current generated by pumping in the absence of gradients in potential energy, density or temperature is associated with non-trivial dynamics. A representative example is charge pumping that is associated with the quantum Hall effect and the quantum anomalous Hall effect . Spin pumping, the spin equivalent of charge pumping, refers to the emission of a spin current by magnetization dynamics . Previous studies have focused solely on transversal spin pumping arising from classical dynamics, which corresponds to precessing atomic moments with constant magnitude. However, longitudinal spin pumping arising from quantum fluctuations, which correspond to a temporal change in the atomic moment’s magnitude, remains unexplored. Here we experimentally investigate longitudinal spin pumping using iron–rhodium (FeRh), which undergoes a first-order antiferromagnet-to-ferromagnet phase transition during which the atomic moment’s magnitude varies over time. By injecting a charge current into a FeRh/platinum bilayer, we induce a rapid phase transition of FeRh in nanoseconds, leading to the emission of a spin current to the platinum layer. The observed inverse spin Hall signal is about one order of magnitude larger than expected for transversal spin pumping, suggesting the presence of longitudinal spin pumping driven by quantum fluctuations and indicating its superiority over classical transversal spin pumping. Our result highlights the significance of quantum fluctuations in spin pumping and holds broad applicability in diverse angular momentum dynamics, such as laser-induced ultrafast demagnetization , orbital pumping and quantum spin transfer .

『摘要』 在没有势能、密度或温度梯度的情况下,通过泵浦产生的粒子流与非平庸动力学相关。一个典型的例子是与量子霍尔效应和量子反常霍尔效应相关的电荷泵浦。自旋泵浦是电荷泵浦的自旋对应物,指的是通过磁化动力学发射自旋流。以往的研究仅关注由经典动力学产生的横向自旋泵浦,这对应于原子矩以恒定大小进行进动。然而,由量子涨落产生的纵向自旋泵浦(对应于原子矩大小的时间变化)仍未被探索。在此,我们使用铁-铑(FeRh)对纵向自旋泵浦进行了实验研究,铁-铑在经历一阶反铁磁-铁磁相变过程中,其原子矩的大小会随时间变化。通过向FeRh/铂双层结构中注入电荷流,我们在纳秒时间内诱导了FeRh的快速相变,从而向铂层发射自旋流。观察到的逆自旋霍尔信号比预期的横向自旋泵浦的信号大一个数量级,这表明存在由量子涨落驱动的纵向自旋泵浦,并显示出其相对于经典横向自旋泵浦的优势。我们的研究结果强调了量子涨落在自旋泵浦中的重要性,并在激光诱导的超快退磁、轨道泵浦和量子自旋转移等多种角动量动力学中具有广泛的应用前景。
『总结』 本研究通过实验证实了由量子涨落驱动的纵向自旋泵浦现象,并强调了其在多种角动量动力学中的重要性和应用潜力。
【闲叙】

『Abstract』Understanding the collective quantum dynamics of non-equilibrium many-body systems is an outstanding challenge in quantum science. In particular, dynamics driven by quantum fluctuations are important for the formation of exotic quantum phases of matter , fundamental high-energy processes , quantum metrology and quantum algorithms . Here we use a programmable quantum simulator based on Rydberg atom arrays to experimentally study collective dynamics across a (2+1)-dimensional Ising quantum phase transition. After crossing the quantum critical point, we observe a gradual growth of correlations through coarsening of antiferromagnetically ordered domains . By deterministically preparing and following the evolution of ordered domains, we show that the coarsening is driven by the curvature of domain boundaries, and find that the dynamics accelerate with proximity to the quantum critical point. We quantitatively explore these phenomena and further observe long-lived oscillations of the order parameter, corresponding to an amplitude (‘Higgs’) mode . These observations offer a viewpoint into emergent collective dynamics in strongly correlated quantum systems and non-equilibrium quantum processes.

『摘要』 理解非平衡多体系统的集体量子动力学是量子科学中的一个重大挑战。特别是,由量子涨落驱动的动力学对于奇异量子物相的形成、基本高能过程、量子计量学和量子算法至关重要。在此,我们使用基于里德伯原子阵列的可编程量子模拟器,对(2+1)维伊辛量子相变中的集体动力学进行了实验研究。在跨越量子临界点后,我们观察到通过反铁磁有序畴的粗化,相关性逐渐增强。我们通过确定性地制备并追踪有序畴的演化,表明粗化是由畴边界的曲率驱动的,并且发现随着接近量子临界点,动力学过程会加快。我们对这些现象进行了定量探索,并进一步观察到有序参数的长期振荡,这对应于振幅(“希格斯”)模式。这些观察结果为强关联量子系统和非平衡量子过程中的集体动力学提供了新视角。
『总结』 本研究利用基于里德伯原子阵列的量子模拟器,实验探究了(2+1)维伊辛量子相变中的集体动力学,发现了由畴边界曲率驱动的粗化现象及加速动力学,并观察到有序参数的长期振荡。
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『Abstract』The fate of the West Antarctic Ice Sheet (WAIS) is the largest cause of uncertainty in long-term sea-level projections. In the last interglacial (LIG) around 125,000 years ago, data suggest that sea level was several metres higher than today , and required a significant contribution from Antarctic ice loss, with WAIS usually implicated. Antarctica and the Southern Ocean were warmer than today , by amounts comparable to those expected by 2100 under moderate to high future warming scenarios. However, direct evidence about the size of WAIS in the LIG is sparse. Here we use sea salt data from an ice core from Skytrain Ice Rise, adjacent to WAIS, to show that, during most of the LIG, the Ronne Ice Shelf was still in place, and close to its current extent. Water isotope data are consistent with a retreat of WAIS , but seem inconsistent with more dramatic model realizations in which both WAIS and the large Antarctic ice shelves were lost. This new constraint calls for a reappraisal of other elements of the LIG sea-level budget. It also weakens the observational basis that motivated model simulations projecting the highest end of projections for future rates of sea-level rise to 2300 and beyond.

『摘要』 西南极冰盖(WAIS)的命运是长期海平面预测中最大的不确定因素。大约在12.5万年前的上一个间冰期(LIG),有数据显示海平面比现在高出数米,南极冰盖的大量流失是主要原因,而西南极冰盖通常与此相关。当时南极和南大洋的温度比现在高,升高的幅度与未来中等至高变暖情境下2100年的预期升温幅度相当。然而,关于西南极冰盖在上一个间冰期的规模,直接证据很少。在本文中,我们使用了来自西南极冰盖附近Skytrain冰穹的冰芯中的海盐数据,结果表明,在上一个间冰期的大部分时间里,龙尼冰架仍然存在,并且接近其现在的范围。水同位素数据与西南极冰盖退缩的情况一致,但似乎与更为剧烈的模型预测结果不一致,在那些预测中,西南极冰盖和南极大型冰架均已消失。这一新发现要求重新评估上一个间冰期海平面预算中的其他要素。同时,这也削弱了模型模拟的观察基础,这些模拟曾预测到2300年及以后海平面上升速率将达到最高值。
『总结』 新研究表明西南极冰盖在上个间冰期大部分时间仍存在,这一发现要求重新评估海平面预测模型,并削弱了预测未来海平面大幅上升观点的观察基础。
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『Abstract』Female mammalian cells have two X chromosomes, one of maternal origin and one of paternal origin. During development, one X chromosome randomly becomes inactivated . This renders either the maternal X (X m ) chromosome or the paternal X (X p ) chromosome inactive, causing X mosaicism that varies between female individuals, with some showing considerable or complete skew of the X chromosome that remains active . Parent-of-X origin can modify epigenetics through DNA methylation and possibly gene expression; thus, mosaicism could buffer dysregulated processes in ageing and disease. However, whether X skew or its mosaicism alters functions in female individuals is largely unknown. Here we tested whether skew towards an active X m chromosome influences the brain and body—and then delineated unique features of X m neurons and X p neurons. An active X m chromosome impaired cognition in female mice throughout the lifespan and led to worsened cognition with age. Cognitive deficits were accompanied by X m -mediated acceleration of biological or epigenetic ageing of the hippocampus, a key centre for learning and memory, in female mice. Several genes were imprinted on the X m chromosome of hippocampal neurons, suggesting silenced cognitive loci. CRISPR-mediated activation of X m -imprinted genes improved cognition in ageing female mice. Thus, the X m chromosome impaired cognition, accelerated brain ageing and silenced genes that contribute to cognition in ageing. Understanding how X m impairs brain function could lead to an improved understanding of heterogeneity in cognitive health in female individuals and to X-chromosome-derived pathways that protect against cognitive deficits and brain ageing.

『摘要』 雌性哺乳动物细胞有两条X染色体,一条来自母亲,一条来自父亲。在发育过程中,其中一条X染色体会随机失活。这会导致母系X(X m)染色体或父系X(X p)染色体失活,从而使不同雌性个体间呈现X染色体嵌合体差异,有些个体的活性X染色体存在相当大的偏斜或完全偏斜。亲本X染色体的来源可通过DNA甲基化以及可能的基因表达来修饰表观遗传;因此,嵌合体可减轻衰老和疾病中的失调过程。然而,X染色体偏斜或其嵌合体是否会改变雌性个体的功能,在很大程度上仍不得而知。本研究测试了活性X m染色体的偏斜是否会影响大脑和身体,并描述了X m神经元和X p神经元的独特特征。活性X m染色体在整个生命周期内都会损害雌性小鼠的认知能力,并导致随年龄增长认知能力下降。认知缺陷的同时还伴随着雌性小鼠海马体(学习和记忆的关键中心)生物或表观遗传衰老的X m介导加速。海马体神经元中的X m染色体上存在几个印记基因,表明认知基因座沉默。CRISPR介导的X m印记基因激活改善了老年雌性小鼠的认知能力。因此,X m染色体损害认知能力,加速大脑衰老,并沉默有助于老年认知的基因。了解X m如何损害大脑功能,有助于更好地理解雌性个体认知健康的异质性以及防止认知缺陷和大脑衰老的X染色体衍生途径。
『总结』 研究发现活性X m染色体偏斜会损害雌性小鼠的认知能力,加速大脑衰老,并导致认知相关基因沉默,这有助于研究雌性个体认知健康差异及抗认知衰退和大脑衰老的新途径。
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『Abstract』The robustness of the macroscopic quantum nature of a superconductor can be characterized by the superfluid stiffness, ρ s , a quantity that describes the energy required to vary the phase of the macroscopic quantum wavefunction. In unconventional superconductors, such as cuprates, the low-temperature behaviour of ρ s markedly differs from that of conventional superconductors owing to quasiparticle excitations from gapless points (nodes) in momentum space. Intensive research on the recently discovered magic-angle twisted graphene family has revealed, in addition to superconducting states, strongly correlated electronic states associated with spontaneously broken symmetries, inviting the study of ρ s to uncover the potentially unconventional nature of its superconductivity. Here we report the measurement of ρ s in magic-angle twisted trilayer graphene (TTG), revealing unconventional nodal-gap superconductivity. Utilizing radio-frequency reflectometry techniques to measure the kinetic inductive response of superconducting TTG coupled to a microwave resonator, we find a linear temperature dependence of ρ s at low temperatures and nonlinear Meissner effects in the current-bias dependence, both indicating nodal structures in the superconducting order parameter. Furthermore, the doping dependence shows a linear correlation between the zero-temperature ρ s and the superconducting transition temperature T c , reminiscent of Uemura’s relation in cuprates, suggesting phase-coherence-limited superconductivity. Our results provide strong evidence for nodal superconductivity in TTG and put strong constraints on the mechanisms of these graphene-based superconductors.

『摘要』 超导体宏观量子特性的稳健性可以通过超流刚度ρs来表征,ρs描述了改变宏观量子波函数相位所需的能量。在非传统超导体(如铜酸盐)中,ρs的低温行为与传统超导体明显不同,这是由于动量空间中无间隙点(节点)处的准粒子激发所致。最近发现的魔角扭曲石墨烯系列材料的深入研究表明,除了超导态外,还存在与自发破缺对称性相关的强相关电子态,这促使人们研究ρs,以揭示其超导性可能具有的非传统特性。在此,我们报告了魔角扭曲三层石墨烯(TTG)中ρs的测量结果,揭示了其非传统的节点-间隙超导性。我们利用射频反射技术测量了与微波谐振器耦合的超导TTG的动力学感应响应,发现ρs在低温下呈线性温度依赖性,并且在电流偏置依赖性中表现出非线性迈斯纳效应,这两者均表明超导序参量中存在节点结构。此外,掺杂依赖性显示零温度ρs与超导转变温度Tc之间存在线性相关性,这与铜酸盐中的乌穆拉关系相似,表明这是一种相位相干性受限的超导性。我们的研究结果为TTG中的节点超导性提供了有力证据,并对这类基于石墨烯的超导体的机制施加了严格限制。
『总结』 研究发现魔角扭曲三层石墨烯表现出非传统的节点-间隙超导性,其超流刚度具有线性温度依赖性和非线性迈斯纳效应,为理解石墨烯基超导体的机制提供了重要线索。
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『Abstract』Io experiences tidal deformation as a result of its eccentric orbit around Jupiter, which provides a primary energy source for Io’s continuing volcanic activity and infrared emission . The amount of tidal energy dissipated within Io is enormous and has been suggested to support the large-scale melting of its interior and the formation of a global subsurface magma ocean. If Io has a shallow global magma ocean, its tidal deformation would be much larger than in the case of a more rigid, mostly solid interior . Here we report the measurement of Io’s tidal deformation, quantified by the gravitational tidal Love number k 2 , enabled by two recent flybys of the Juno spacecraft. By combining Juno and Galileo Doppler data from the NASA Deep Space Network and astrometric observations, we recover Re( k 2 ) of 0.125 ± 0.047 (1 σ ) and the tidal dissipation parameter Q of 11.4 ± 3.6 (1 σ ). These measurements confirm that a shallow global magma ocean in Io does not exist and are consistent with Io having a mostly solid mantle . Our results indicate that tidal forces do not universally create global magma oceans, which may be prevented from forming owing to rapid melt ascent, intrusion and eruption , so even strong tidal heating—such as that expected on several known exoplanets and super-Earths —may not guarantee the formation of magma oceans on moons or planetary bodies.

『摘要』 木卫一因其绕木星运行的偏心轨道而发生潮汐形变,这为木卫一持续的火山活动和红外辐射提供了主要能量来源。木卫一内部消散的潮汐能量巨大,据推测足以支持其内部的大规模熔化以及全球性地下岩浆海洋的形成。如果木卫一有一个较浅的全球性岩浆海洋,其潮汐形变将比内部更坚硬、主要为固态的情况下大得多。本文报告了通过朱诺号探测器最近两次飞掠测得的木卫一潮汐形变,以引力潮汐洛夫数k2量化。我们结合了来自美国国家航空航天局深空网络的朱诺号和伽利略号的多普勒数据以及天体测量观测数据,得出k2的实部Re(k2)为0.125±0.047(1σ),潮汐耗散参数Q为11.4±3.6(1σ)。这些测量结果证实,木卫一并不存在浅层的全球性岩浆海洋,而是拥有一个主要为固态的地幔。我们的研究结果表明,潮汐力并不会普遍形成全球性岩浆海洋,由于岩浆快速上升、侵入和喷发,可能会阻止全球性岩浆海洋的形成,因此,即使像在一些已知的外行星和超级地球上预期的那样有强烈的潮汐加热,也不能保证卫星或行星体会形成岩浆海洋。
『总结』 研究表明木卫一不存在浅层全球性岩浆海洋,其潮汐形变测量结果支持其主要为固态地幔,且潮汐力不一定会导致全球性岩浆海洋的形成。
【闲叙】

『Abstract』Metabolites derived from the intestinal microbiota, including bile acids (BA), extensively modulate vertebrate physiology, including development , metabolism , immune responses and cognitive function . However, to what extent host responses balance the physiological effects of microbiota-derived metabolites remains unclear . Here, using untargeted metabolomics of mouse tissues, we identified a family of BA–methylcysteamine (BA–MCY) conjugates that are abundant in the intestine and dependent on vanin 1 (VNN1), a pantetheinase highly expressed in intestinal tissues. This host-dependent MCY conjugation inverts BA function in the hepatobiliary system. Whereas microbiota-derived free BAs function as agonists of the farnesoid X receptor (FXR) and negatively regulate BA production, BA–MCYs act as potent antagonists of FXR and promote expression of BA biosynthesis genes in vivo. Supplementation with stable-isotope-labelled BA–MCY increased BA production in an FXR-dependent manner, and BA–MCY supplementation in a mouse model of hypercholesteraemia decreased lipid accumulation in the liver, consistent with BA–MCYs acting as intestinal FXR antagonists. The levels of BA–MCY were reduced in microbiota-deficient mice and restored by transplantation of human faecal microbiota. Dietary intervention with inulin fibre further increased levels of both free BAs and BA–MCY levels, indicating that BA–MCY production by the host is regulated by levels of microbiota-derived free BAs. We further show that diverse BA–MCYs are also present in human serum. Together, our results indicate that BA–MCY conjugation by the host balances host-dependent and microbiota-dependent metabolic pathways that regulate FXR-dependent physiology.

『摘要』 肠道微生物产生的代谢物,包括胆汁酸(BA),可广泛调节脊椎动物的生理机能,包括发育、代谢、免疫反应和认知功能。然而,宿主反应在多大程度上平衡微生物衍生代谢物的生理作用仍不清楚。本研究通过小鼠组织的非靶向代谢组学研究,鉴定出一类在肠道中丰富且依赖于香草酸-1(VNN1)(一种在肠道组织中高度表达的泛酸酯酶)的胆汁酸-甲基半胱氨酸(BA-MCY)缀合物。这种宿主依赖的MCY缀合作用逆转了胆汁酸在肝胆系统中的功能。微生物衍生的游离胆汁酸作为法尼醇X受体(FXR)的激动剂,负向调节胆汁酸的产生,而BA-MCYs则是FXR的强效拮抗剂,可在体内促进胆汁酸生物合成基因的表达。补充稳定同位素标记的BA-MCY以FXR依赖的方式增加胆汁酸的产生,并且在高胆固醇血症小鼠模型中补充BA-MCY可减少肝脏中的脂质积累,这与BA-MCYs作为肠道FXR拮抗剂的作用一致。在无微生物小鼠中,BA-MCY的水平降低,而通过移植人类粪便微生物可使其恢复。通过菊粉纤维进行饮食干预可进一步增加游离胆汁酸和BA-MCY的水平,表明宿主产生的BA-MCY受微生物衍生的游离胆汁酸水平的调节。本研究还进一步表明,人血清中也存在多种BA-MCYs。综上,我们的研究结果表明,宿主进行的BA-MCY缀合作用平衡了依赖宿主和依赖微生物的代谢途径,这些途径可调节依赖FXR的生理机能。
『总结』 研究发现,宿主依赖的胆汁酸-甲基半胱氨酸缀合作用通过调节FXR信号通路,平衡了宿主和微生物依赖的代谢途径。
【闲叙】

『Abstract』Lung metastases occur in up to 54% of patients with metastatic tumours . Contributing factors to this high frequency include the physical properties of the pulmonary system and a less oxidative environment that may favour the survival of cancer cells . Moreover, secreted factors from primary tumours alter immune cells and the extracellular matrix of the lung, creating a permissive pre-metastatic environment primed for the arriving cancer cells . Nutrients are also primed during pre-metastatic niche formation . Yet, whether and how nutrients available in organs in which tumours metastasize confer cancer cells with aggressive traits is mostly undefined. Here we found that pulmonary aspartate triggers a cellular signalling cascade in disseminated cancer cells, resulting in a translational programme that boosts aggressiveness of lung metastases. Specifically, we observe that patients and mice with breast cancer have high concentrations of aspartate in their lung interstitial fluid. This extracellular aspartate activates the ionotropic N -methyl- d -aspartate receptor in cancer cells, which promotes CREB-dependent expression of deoxyhypusine hydroxylase ( DOHH ). DOHH is essential for hypusination, a post-translational modification that is required for the activity of the non-classical translation initiation factor eIF5A. In turn, a translational programme with TGFβ signalling as a central hub promotes collagen synthesis in lung-disseminated breast cancer cells. We detected key proteins of this mechanism in lung metastases from patients with breast cancer. In summary, we found that aspartate, a classical biosynthesis metabolite, functions in the lung environment as an extracellular signalling molecule to promote aggressiveness of metastases.

『摘要』 肺转移发生在高达54%的转移性肿瘤患者身上。造成这一高频率的因素包括肺系统的物理特性和较低的氧化环境,这种环境可能有利于癌细胞的存活。此外,原发肿瘤分泌的物质会改变免疫细胞和肺的细胞外基质,为即将到来的癌细胞创造一个有利的转移前环境。在转移前生态位形成过程中,营养物质也做好了准备。然而,肿瘤转移所在器官中的营养物质是否以及如何赋予癌细胞侵袭性特征,目前尚不清楚。本研究发现,肺中的天冬氨酸会在扩散的癌细胞中触发一系列细胞信号,从而产生一个促进肺转移侵袭性的翻译程序。具体而言,我们观察到乳腺癌患者和小鼠的肺间质液中天冬氨酸浓度较高。这种细胞外的天冬氨酸会激活癌细胞中的离子型N-甲基-D-天冬氨酸受体,进而促进CREB依赖性脱氧羟赖氨酸羟化酶(DOHH)的表达。DOHH对于羟赖氨酸化至关重要,羟赖氨酸化是一种非经典翻译起始因子eIF5A活性所需的翻译后修饰。相应地,一个以转化生长因子β(TGFβ)信号传导为中心的翻译程序会促进肺扩散乳腺癌细胞中的胶原合成。我们在乳腺癌患者的肺转移灶中检测到了这一机制的关键蛋白。
『总结』 研究发现,天冬氨酸作为一种经典的生物合成代谢产物,在肺环境中作为细胞外信号分子促进转移的侵袭性。
【闲叙】

『Abstract』Non-ribosomal peptide synthetases are assembly line biosynthetic pathways that are used to produce critical therapeutic drugs and are typically arranged as large multi-domain proteins called megasynthetases . They synthesize polypeptides using peptidyl carrier proteins that shuttle each amino acid through modular loading, modification and elongation steps, and remain challenging to structurally characterize, owing in part to the inherent dynamics of their multi-domain and multi-modular architectures . Here we have developed site-selective crosslinking probes to conformationally constrain and resolve the interactions between carrier proteins and their partner enzymatic domains . We apply tetrazine click chemistry to trap the condensation of two carrier protein substrates within the active site of the condensation domain that unites the first two modules of tyrocidine biosynthesis and report the high-resolution cryo-EM structure of this complex. Together with the X-ray crystal structure of the first carrier protein crosslinked to its epimerization domain, these structures highlight captured intermodular recognition events and define the processive movement of a carrier protein from one catalytic step to the next. Characterization of these structural relationships remains central to understanding the molecular details of these unique synthetases and critically informs future synthetic biology design of these pathways.

『摘要』 非核糖体肽合成酶是用于生产关键治疗药物的一种流水线式生物合成途径,通常表现为被称为巨型合成酶的大型多结构域蛋白。它们利用肽基载体蛋白合成多肽,该载体蛋白通过模块化的加载、修饰和延长步骤转运每种氨基酸,并且由于其多结构域和多模块化架构的固有动态性,这些合成酶的结构特征仍然难以解析。在这里,我们开发了位点选择性交联探针,用于限制载体蛋白的构象并解析载体蛋白与其伴侣酶结构域之间的相互作用。我们应用四嗪点击化学方法,捕捉两个载体蛋白底物在凝聚结构域活性位点内的缩合,该结构域结合了酪罗西丁生物合成的前两个模块,并报告了这一复合物的高分辨率冷冻电子显微镜结构。结合首个与差向异构化结构域交联的载体蛋白的X射线晶体结构,这些结构凸显了捕获的模块间识别事件,并定义了载体蛋白从一个催化步骤到下一个的连续运动。解析这些结构关系对于理解这些独特合成酶的分子细节至关重要,并为未来这些途径的合成生物学设计提供了关键信息。
『总结』 研究开发了位点选择性交联探针,解析了非核糖体肽合成酶中载体蛋白与酶结构域的相互作用,并通过高分辨率结构分析揭示了其分子机制,为合成生物学设计提供了重要信息。
【闲叙】

『Abstract』Crosslinked thermosets are highly durable materials, but overcoming their petrochemical origins and inability to be recycled poses a grand challenge . Many strategies to access crosslinked polymers that are bioderived or degradable-by-design have been proposed, but they require several resource-intensive synthesis and purification steps and are not yet feasible alternatives to conventional consumer materials . Here we present a modular, one-pot synthesis of degradable thermosets from the commercially available, biosourced monomer 2,3-dihydrofuran (DHF) . In the presence of a ruthenium catalyst and photoacid generator, DHF undergoes slow ring-opening metathesis polymerization to give a soft polymer; then, exposure to light triggers strong acid generation and promotes the cationic polymerization of the same DHF monomer to spatially crosslink and strengthen the material . By manipulating catalyst loading and light exposure, we can access materials with physical properties spanning orders of magnitude and achieve spatially resolved material domains. Importantly, the DHF-based thermosets undergo stimuli-selective degradation and can be recycled to the monomer under mild heating. The use of two distinct polymerization mechanisms on a single functional group allows the synthesis of degradable and recyclable thermoset materials with precisely controlled properties.

『摘要』 交联热固性材料是一种高度耐用的材料,但要克服其石化来源和无法回收的问题是一项巨大挑战。人们已提出许多策略来获取生物衍生或按设计可降解的交联聚合物,但这些策略需要多个资源密集型的合成和纯化步骤,目前尚无法成为传统消费材料的可行替代品。本文介绍了一种模块化的、一锅法合成可降解热固性材料的方法,该方法使用的是市面上可获得的、生物源的单体2,3-二氢呋喃(DHF)。在钌催化剂和光酸产生剂的存在下,DHF发生缓慢的开环易位聚合,生成一种软聚合物;随后,曝光会触发强酸的生成,并促进相同DHF单体的阳离子聚合,使其在空间上发生交联并使材料得到强化。通过调整催化剂用量和曝光量,我们可以获得物理性能跨越多个数量级的材料,并实现空间分辨的材料域。重要的是,基于DHF的热固性材料可发生刺激性选择性降解,并且在温和加热条件下可回收为单体。在单一官能团上使用两种不同的聚合机制,可以合成具有精确控制性能的可降解和可回收热固性材料。
『总结』 本研究通过一锅法,利用2,3-二氢呋喃单体合成了可降解且可回收的热固性材料,解决了传统交联热固性材料无法回收的问题,并通过调整合成条件实现了对材料性能的精确控制。
【闲叙】

『Abstract』Biological ageing can be defined as a gradual loss of homeostasis across various aspects of molecular and cellular function . Mammalian brains consist of thousands of cell types , which may be differentially susceptible or resilient to ageing. Here we present a comprehensive single-cell RNA sequencing dataset containing roughly 1.2 million high-quality single-cell transcriptomes of brain cells from young adult and aged mice of both sexes, from regions spanning the forebrain, midbrain and hindbrain. High-resolution clustering of all cells results in 847 cell clusters and reveals at least 14 age-biased clusters that are mostly glial types. At the broader cell subclass and supertype levels, we find age-associated gene expression signatures and provide a list of 2,449 unique differentially expressed genes (age-DE genes) for many neuronal and non-neuronal cell types. Whereas most age-DE genes are unique to specific cell types, we observe common signatures with ageing across cell types, including a decrease in expression of genes related to neuronal structure and function in many neuron types, major astrocyte types and mature oligodendrocytes, and an increase in expression of genes related to immune function, antigen presentation, inflammation, and cell motility in immune cell types and some vascular cell types. Finally, we observe that some of the cell types that demonstrate the greatest sensitivity to ageing are concentrated around the third ventricle in the hypothalamus, including tanycytes, ependymal cells, and certain neuron types in the arcuate nucleus, dorsomedial nucleus and paraventricular nucleus that express genes canonically related to energy homeostasis. Many of these types demonstrate both a decrease in neuronal function and an increase in immune response. These findings suggest that the third ventricle in the hypothalamus may be a hub for ageing in the mouse brain. Overall, this study systematically delineates a dynamic landscape of cell-type-specific transcriptomic changes in the brain associated with normal ageing that will serve as a foundation for the investigation of functional changes in ageing and the interaction of ageing and disease.

『摘要』 生物衰老可定义为分子和细胞功能各方面稳态的逐渐丧失。哺乳动物的大脑由数千种细胞类型组成,这些细胞类型对衰老的易感性或抗逆性可能各不相同。本文提供了一个全面的单细胞RNA测序数据集,其中包含来自年轻成年和老年雄性和雌性小鼠的前脑、中脑和后脑区域的约120万个高质量的脑细胞单细胞转录组。对所有细胞进行高分辨率聚类,得到847个细胞簇,并发现至少14个与年龄相关的簇,主要为胶质细胞类型。在更广泛的细胞亚类和超类层面,本文发现了与年龄相关的基因表达特征,并列出了2449个在许多神经元和非神经元细胞类型中差异表达的独特基因(年龄差异表达基因)。虽然大多数年龄差异表达基因在特定细胞类型中是唯一的,但本文也观察到了跨细胞类型与衰老相关的共同特征,包括许多神经元类型、主要星形胶质细胞类型和成熟少突胶质细胞中,与神经元结构和功能相关的基因表达减少;以及在免疫细胞类型和某些血管细胞类型中,与免疫功能、抗原呈递、炎症和细胞运动相关的基因表达增加。最后,本文观察到一些对衰老最敏感的细胞类型集中在下丘脑的第三脑室周围,包括鞣质细胞、室管膜细胞以及弓状核、背内侧核和室旁核中表达与能量稳态经典相关基因的某些神经元类型。其中许多类型均表现出神经元功能降低和免疫反应增强。这些发现表明,下丘脑的第三脑室可能是小鼠大脑衰老的中心。总体而言,本研究系统地描绘了与正常衰老相关的大脑细胞类型特异性转录组变化的动态图谱,这将为探究衰老过程中的功能变化以及衰老与疾病的相互作用奠定基础。
『总结』 本研究通过单细胞RNA测序揭示了小鼠大脑中与正常衰老相关的细胞类型特异性转录组变化,发现下丘脑的第三脑室可能是大脑衰老的中心。
【闲叙】

『Abstract』Cancer cells in the tumour microenvironment use various mechanisms to evade the immune system, particularly T cell attack . For example, metabolic reprogramming in the tumour microenvironment and mitochondrial dysfunction in tumour-infiltrating lymphocytes (TILs) impair antitumour immune responses . However, detailed mechanisms of such processes remain unclear. Here we analyse clinical specimens and identify mitochondrial DNA (mtDNA) mutations in TILs that are shared with cancer cells. Moreover, mitochondria with mtDNA mutations from cancer cells are able to transfer to TILs. Typically, mitochondria in TILs readily undergo mitophagy through reactive oxygen species. However, mitochondria transferred from cancer cells do not undergo mitophagy, which we find is due to mitophagy-inhibitory molecules. These molecules attach to mitochondria and together are transferred to TILs, which results in homoplasmic replacement. T cells that acquire mtDNA mutations from cancer cells exhibit metabolic abnormalities and senescence, with defects in effector functions and memory formation. This in turn leads to impaired antitumour immunity both in vitro and in vivo. Accordingly, the presence of an mtDNA mutation in tumour tissue is a poor prognostic factor for immune checkpoint inhibitors in patients with melanoma or non-small-cell lung cancer. These findings reveal a previously unknown mechanism of cancer immune evasion through mitochondrial transfer and can contribute to the development of future cancer immunotherapies.

『摘要』 肿瘤微环境中的癌细胞利用多种机制逃避免疫系统,尤其是T细胞的攻击。例如,肿瘤微环境中的代谢重编程和肿瘤浸润淋巴细胞(TILs)中的线粒体功能障碍会损害抗肿瘤免疫反应。然而,这些过程的详细机制尚不清楚。本研究分析了临床样本,发现肿瘤浸润淋巴细胞中存在与癌细胞共有的线粒体DNA(mtDNA)突变。此外,癌细胞中具有mtDNA突变的线粒体能够转移到肿瘤浸润淋巴细胞中。通常,肿瘤浸润淋巴细胞中的线粒体易通过活性氧发生线粒体自噬。然而,从癌细胞转移而来的线粒体不会发生线粒体自噬,本研究发现这是由于存在抑制线粒体自噬的分子。这些分子附着在线粒体上并随之转移到肿瘤浸润淋巴细胞中,导致纯合性线粒体DNA替换。从癌细胞中获得mtDNA突变的T细胞会表现出代谢异常和衰老,同时效应功能和记忆形成出现缺陷。这反过来又会导致体内和体外抗肿瘤免疫受损。因此,肿瘤组织中存在mtDNA突变是黑色素瘤或非小细胞肺癌患者免疫检查点抑制剂疗效不佳的预后因素。这些研究结果揭示了一种先前未知的通过线粒体转移实现癌症免疫逃避的机制,并有助于未来癌症免疫疗法的发展。
『总结』 本研究发现了癌细胞通过线粒体转移和mtDNA突变逃避免疫系统的新机制,为癌症免疫治疗的发展提供了新思路。
【闲叙】

『Abstract』Dense crowds form some of the most dangerous environments in modern society . Dangers arise from uncontrolled collective motions, leading to compression against walls, suffocation and fatalities . Our current understanding of crowd dynamics primarily relies on heuristic collision models, which effectively capture the behaviour observed in small groups of people . However, the emergent dynamics of dense crowds, composed of thousands of individuals, remains a formidable many-body problem lacking quantitative experimental characterization and explanations rooted in first principles. Here we analyse the dynamics of thousands of densely packed individuals at the San Fermin festival (Spain) and infer a physical theory of dense crowds in confinement. Our measurements reveal that dense crowds can self-organize into macroscopic chiral oscillators, coordinating the orbital motion of hundreds of individuals without external guidance. Guided by these measurements and symmetry principles, we construct a mechanical model of dense-crowd motion. Our model demonstrates that emergent odd frictional forces drive a non-reciprocal phase transition towards collective chiral oscillations, capturing all our experimental observations. To test the robustness of our findings, we show that similar chiral dynamics emerged at the onset of the 2010 Love Parade disaster and propose a protocol that could help anticipate these previously unpredictable dynamics.

『摘要』 现代社会中,密集人群构成了最危险的环境之一。失控的集体运动会带来危险,导致人群被挤压到墙边、窒息甚至死亡。目前,我们对人群动态的理解主要基于启发式碰撞模型,这些模型能够有效地捕捉小群体中的行为。然而,由数千人组成的密集人群的涌现动态仍然是一个巨大的多体问题,缺乏基于第一性原理的定量实验表征和解释。在本文中,我们分析了西班牙圣费尔明节上数千名密集聚集者的动态,并推断出了受限空间内密集人群的物理理论。我们的测量结果表明,密集人群可以自我组织成宏观的手性振荡器,无需外部引导就能协调数百人的轨道运动。在这些测量结果和对称性原则的指导下,我们构建了一个密集人群运动的力学模型。我们的模型表明,涌现的奇数摩擦力驱动了向集体手性振荡的非互易相变,捕捉到了我们所有的实验观察结果。为了验证我们的发现的稳健性,我们表明2010年Love Parade灾难发生时也出现了类似的手性动态,并提出了一种协议,可能有助于预测这些以前无法预测的动态。
『总结』 本研究通过分析西班牙圣费尔明节上密集人群的动态,发现了人群可以自我组织成手性振荡器,并构建了相应的力学模型,为预测和理解密集人群中的危险动态提供了新的视角。
【闲叙】

『Abstract』Non-ribosomal peptide synthetases (NRPSs) are megaenzymes responsible for the biosynthesis of many clinically important natural products, from early modern medicines (penicillin, bacitracin) to current blockbuster drugs (cubicin, vancomycin) and newly approved therapeutics (rezafungin) . The key chemical step in these biosyntheses is amide bond formation between aminoacyl building blocks, catalysed by the condensation (C) domain . There has been much debate over the mechanism of this reaction . NRPS condensation has been difficult to fully characterize because it is one of many successive reactions in the NRPS synthetic cycle and because the canonical substrates are each attached transiently as thioesters to mobile carrier domains, which are often both contained in the same very flexible protein as the C domain. Here we have produced a dimodular NRPS protein in two parts, modified each with appropriate non-hydrolysable substrate analogues , assembled the two parts with protein ligation , and solved the structures of the substrate- and product-bound states. The structures show the precise orientation of the megaenzyme preparing the nucleophilic attack of its key chemical step, and enable biochemical assays and quantum mechanical simulations to precisely interrogate the reaction. These data suggest that NRPS C domains use a concerted reaction mechanism, whereby the active-site histidine likely functions not as a general base, but as a crucial stabilizing hydrogen bond acceptor for the developing ammonium.

『摘要』 非核糖体肽合成酶(NRPSs)是负责合成许多具有临床重要性的天然产物的大型酶,这些产物包括早期现代药物(青霉素、杆菌肽)到当前的畅销药物(古巴菌素、万古霉素)以及新获批的治疗药物(雷扎芬净)。这些生物合成的关键化学步骤是由缩合(C)结构域催化的氨基酰基结构单元之间的酰胺键形成。关于这一反应的机制一直存在诸多争议。NRPS缩合难以完全表征,因为它仅是NRPS合成循环中的众多连续反应之一,而且其规范底物均作为硫酯短暂地连接于可移动的载体结构域,而这些载体结构域通常与C结构域都包含在同一个高度灵活的蛋白质中。本研究制作了一种由两部分组成的双模块NRPS蛋白,用适当的非水解底物类似物对每部分进行修饰,通过蛋白质连接技术将这两部分组装起来,并解析了底物结合态和产物结合态的结构。这些结构显示了大型酶在准备其关键化学步骤的亲核攻击时的精确取向,并能够通过生化测定和量子力学模拟来精确探究该反应。这些数据表明,NRPS的C结构域采用协同反应机制,其中活性位点组氨酸可能不是作为广义碱起作用,而是作为发展中铵离子的关键稳定氢键受体。
『总结』 本研究揭示了非核糖体肽合成酶C结构域采用协同反应机制,并通过解析底物结合态和产物结合态的结构,为深入探究其催化机制提供了重要依据。
【闲叙】

『Abstract』The physics of superconductivity in magic-angle twisted bilayer graphene (MATBG) is a topic of keen interest in moire systems research, and it may provide an insight into the pairing mechanism of other strongly correlated materials such as high-critical-temperature superconductors. Here we use d.c. transport and microwave circuit quantum electrodynamics to directly measure the superfluid stiffness of superconducting MATBG through its kinetic inductance. We find the superfluid stiffness to be much larger than expected from conventional Fermi liquid theory. Rather, it is comparable to theoretical predictions and recent experimental indications of quantum geometric effects that are dominant at the magic angle. The temperature dependence of the superfluid stiffness follows a power law, which contraindicates an isotropic Bardeen–Cooper–Schrieffer (BCS) model. Instead, the extracted power-law exponents indicate an anisotropic superconducting gap, whether interpreted in the Fermi liquid framework or by considering the quantum geometry of flat-band superconductivity. Moreover, a quadratic dependence of the superfluid stiffness on both d.c. and microwave current is observed, which is consistent with the Ginzburg–Landau theory. Taken together, our findings show that MATBG is an unconventional superconductor with an anisotropic gap and strongly suggest a connection between quantum geometry, superfluid stiffness and unconventional superconductivity in MATBG. The combined d.c.–microwave measurement platform used here is applicable to the investigation of other atomically thin superconductors.

『摘要』 魔角扭曲双层石墨烯(MATBG)中的超导物理是摩尔纹系统研究中一个备受关注的话题,它或许能够让人们深入了解其他强相关材料(如高临界温度超导体)的配对机制。本研究采用直流传输和微波电路量子电动力学方法,通过测量动力学电感,直接测定了超导MATBG的超流刚度。研究发现,超流刚度远大于传统费米液体理论的预期值,而是与魔角下占主导地位的量子几何效应的理论预测和最新实验结果相当。超流刚度随温度的变化遵循幂律,这与各向同性的巴丁-库珀-施里弗(BCS)模型相矛盾。无论是在费米液体框架内解释,还是考虑平坦带超导的量子几何特性,提取的幂律指数都表明超导能隙具有各向异性。此外,研究还观察到超流刚度与直流电流和微波电流均呈二次方关系,这与金兹堡-朗道理论一致。综上所述,本研究结果表明,MATBG是一种具有各向异性能隙的非传统超导体,并强烈表明MATBG中的量子几何特性、超流刚度和非传统超导性之间存在联系。本研究采用的直流-微波组合测量平台也适用于其他原子级薄超导体的研究。
『总结』 研究发现魔角扭曲双层石墨烯是一种具有各向异性能隙的非传统超导体,其超流刚度与量子几何效应密切相关。
【闲叙】

『Abstract』Stem cells reside in specialized microenvironments, termed niches, at several different locations in tissues . The differential functions of heterogeneous stem cells and niches are important given the increasing clinical applications of stem-cell transplantation and immunotherapy. Whether hierarchical structures among stem cells at distinct niches exist and further control aspects of immune tolerance is unknown. Here we describe previously unknown new hierarchical arrangements in haematopoietic stem cells (HSCs) and bone marrow niches that dictate both regenerative potential and immune privilege. High-level nitric oxide-generating (NO ) HSCs are refractory to immune attack and exhibit delayed albeit robust long-term reconstitution. Such highly immune-privileged, primitive NO HSCs co-localize with distinctive capillaries characterized by primary ciliated endothelium and high levels of the immune-checkpoint molecule CD200. These capillaries regulate the regenerative functions of NO HSCs through the ciliary protein IFT20 together with CD200, endothelial nitric oxide synthase and autophagy signals, which further mediate immunoprotection. Notably, previously described niche constituents, sinusoidal cells and type-H vessels co-localize with less immune-privileged and less potent NO HSCs. Together, we identify highly immune-privileged, late-rising primitive HSCs and characterize their immunoprotective niches comprising specialized vascular domains. Our results indicate that the niche orchestrates hierarchy in stem cells and immune tolerance, and highlight future immunotherapeutic targets.

『摘要』 干细胞存在于组织内多个不同位置的特殊微环境中,即生态位。鉴于干细胞移植和免疫治疗的临床应用日益增多,异质性干细胞和生态位的差异功能显得尤为重要。目前尚不清楚不同生态位的干细胞之间是否存在等级结构以及是否进一步控制免疫耐受的某些方面。本文描述了造血干细胞(HSC)和骨髓生态位中先前未知的新等级排列,这些排列决定了再生潜力和免疫特权。高水平一氧化氮生成(NO)的HSC能抵抗免疫攻击,并表现出虽然延迟但强劲的长期重建能力。这些具有高免疫特权、原始的NO HSC与具有初级纤毛内皮和高水平免疫检查点分子CD200的独特毛细血管共定位。这些毛细血管通过纤毛蛋白IFT20以及CD200、内皮型一氧化氮合酶和自噬信号来调节NO HSC的再生功能,从而进一步介导免疫保护。值得注意的是,先前描述的生态位成分,即窦状细胞和H型血管,与免疫特权较弱且效力较低的NO HSC共定位。综上所述,我们鉴定了具有高免疫特权、后期增殖的原始HSC,并描述了其包含特殊血管域的免疫保护生态位。我们的研究结果表明,生态位决定了干细胞的等级和免疫耐受,并突出了未来的免疫治疗靶点。
『总结』 本研究发现了造血干细胞和骨髓生态位中的新等级结构,这些结构决定了干细胞的再生能力和免疫特权,并提出了潜在的免疫治疗靶点。
【闲叙】

『Abstract』Old age is associated with a decline in cognitive function and an increase in neurodegenerative disease risk . Brain ageing is complex and is accompanied by many cellular changes . Furthermore, the influence that aged cells have on neighbouring cells and how this contributes to tissue decline is unknown. More generally, the tools to systematically address this question in ageing tissues have not yet been developed. Here we generate a spatially resolved single-cell transcriptomics brain atlas of 4.2 million cells from 20 distinct ages across the adult lifespan and across two rejuvenating interventions—exercise and partial reprogramming. We build spatial ageing clocks, machine learning models trained on this spatial transcriptomics atlas, to identify spatial and cell-type-specific transcriptomic fingerprints of ageing, rejuvenation and disease, including for rare cell types. Using spatial ageing clocks and deep learning, we find that T cells, which increasingly infiltrate the brain with age, have a marked pro-ageing proximity effect on neighbouring cells. Surprisingly, neural stem cells have a strong pro-rejuvenating proximity effect on neighbouring cells. We also identify potential mediators of the pro-ageing effect of T cells and the pro-rejuvenating effect of neural stem cells on their neighbours. These results suggest that rare cell types can have a potent influence on their neighbours and could be targeted to counter tissue ageing. Spatial ageing clocks represent a useful tool for studying cell–cell interactions in spatial contexts and should allow scalable assessment of the efficacy of interventions for ageing and disease.

『摘要』 随着年龄的增长,人体认知功能逐渐衰退,神经退行性疾病的风险也会增加。大脑衰老是一个复杂的过程,伴随着许多细胞层面的变化。此外,衰老细胞对周围细胞的影响以及这种影响如何导致组织衰退,目前尚不清楚。总体而言,尚未开发出可系统解决衰老组织中这一问题的工具。本文生成了一个包含来自成人整个生命周期20个不同年龄段以及经过运动和部分重编程两种干预措施后共计420万个细胞的空间分辨单细胞转录组大脑图谱。我们构建了空间衰老时钟,这是一种基于该空间转录组图谱训练的机器学习模型,用于识别衰老、恢复活力和疾病(包括罕见细胞类型)的空间和细胞类型特异性转录组指纹。利用空间衰老时钟和深度学习技术,我们发现随着年龄增长而越来越多地浸润大脑的T细胞对邻近细胞具有显著的促衰老邻近效应。令人惊讶的是,神经干细胞对邻近细胞具有强烈的促恢复活力邻近效应。我们还确定了T细胞促衰老效应和神经干细胞对邻近细胞的促恢复活力效应的潜在介质。这些结果表明,罕见细胞类型对其邻近细胞具有强烈影响,或可成为对抗组织衰老的靶点。空间衰老时钟是研究空间背景下细胞间相互作用的有用工具,应可实现对衰老和疾病干预措施效果的可扩展评估。
『总结』 本研究构建了大脑单细胞转录组图谱和空间衰老时钟,发现T细胞和神经干细胞对邻近细胞分别有促衰老和促恢复活力的作用,提出罕见细胞类型或可成为对抗组织衰老的新靶点。
【闲叙】

『Abstract』Carbon–hydrogen (C–H) bonds are the foundation of essentially every organic molecule, making them an ideal place to do chemical synthesis. The key challenge is achieving selectivity for one particular C( sp )−H bond . In recent years, metalloenzymes have been found to perform C( sp )−H bond functionalization . Despite substantial progresses in the past two decades , enzymatic halogenation and pseudohalogenation of unactivated C( sp )−H—providing a functional handle for further modification—have been achieved with only non-haem iron/α-ketoglutarate-dependent halogenases, and are therefore limited by the chemistry possible with these enzymes . Here we report the discovery and characterization of a previously unknown halogenase ApnU, part of a protein family containing domain of unknown function 3328 (DUF3328). ApnU uses copper in its active site to catalyse iterative chlorinations on multiple unactivated C( sp )−H bonds. By taking advantage of the softer copper centre, we demonstrate that ApnU can catalyse unprecedented enzymatic C( sp )−H bond functionalization such as iodination and thiocyanation. Using biochemical characterization and proteomics analysis, we identified the functional oligomeric state of ApnU as a covalently linked homodimer, which contains three essential pairs—one interchain and two intrachain—of disulfide bonds. The metal-coordination active site in ApnU consists of binuclear type II copper centres, as revealed by electron paramagnetic resonance spectroscopy. This discovery expands the enzymatic capability of C( sp )−H halogenases and provides a foundational understanding of this family of binuclear copper-dependent oxidative enzymes.

『摘要』 碳-氢(C-H)键基本上是所有有机分子的基础,这使其成为进行化学合成的理想场所。其中的关键挑战是实现对特定C(sp)-H键的选择性。近年来,人们发现金属酶可以执行C(sp)-H键的功能化。尽管在过去二十年中取得了重大进展,但非活化C(sp)-H键的酶促卤化和拟卤化——为进一步修饰提供了功能性抓手——仅可通过非血红素铁/α-酮戊二酸依赖性卤化酶来实现,并因此受到这些酶可实现的化学反应的限制。在此,我们报告了一种先前未知的卤化酶ApnU的发现及其特征,该酶是含有功能未知结构域3328(DUF3328)的蛋白质家族的一部分。ApnU在其活性位点使用铜来催化多个非活化C(sp)-H键上的迭代氯化。通过利用较软的铜中心,我们证明ApnU可以催化前所未有的酶促C(sp)-H键功能化,如碘化和硫氰化。通过生物化学特征和蛋白质组学分析,我们确定了ApnU的功能性寡聚状态为共价连接的同源二聚体,其中包含三对必不可少的二硫键——一对链间二硫键和两对链内二硫键。电子顺磁共振光谱显示,ApnU中的金属配位活性位点由双核II型铜中心组成。这一发现扩展了C(sp)-H卤化酶的酶促能力,并为理解这类双核铜依赖性氧化酶提供了基础。
『总结』 研究发现了新的卤化酶ApnU,其利用铜催化非活化C(sp)-H键的功能化,这一发现扩展了对C(sp)-H卤化酶酶促能力的认识。
【闲叙】

『Abstract』As the brain transitions from wakefulness to sleep, processing of external information diminishes while restorative processes, such as glymphatic removal of waste products, are activated. Yet, it is not known what drives brain clearance during sleep. We here employed an array of technologies and identified tightly synchronized oscillations in norepinephrine, cerebral blood volume, and cerebrospinal fluid (CSF) as the strongest predictors of glymphatic clearance during NREM sleep. Optogenetic stimulation of the locus coeruleus induced anti-correlated changes in vasomotion and CSF signal. Furthermore, stimulation of arterial oscillations enhanced CSF inflow, demonstrating that vasomotion acts as a pump driving CSF into the brain. On the contrary, the sleep aid zolpidem suppressed norepinephrine oscillations and glymphatic flow, highlighting the critical role of norepinephrine-driven vascular dynamics in brain clearance. Thus, the micro-architectural organization of NREM sleep, driven by norepinephrine fluctuations and vascular dynamics, is a key determinant for glymphatic clearance.

『摘要』 在大脑从清醒状态过渡到睡眠状态时,外部信息的处理能力减弱,而恢复过程(如通过胶质淋巴系统清除废物)则被激活。然而,目前尚不清楚睡眠期间是什么驱动了大脑的清除过程。本研究采用了一系列技术,发现去甲肾上腺素、脑血容量和脑脊液(CSF)的紧密同步振荡是非快速眼动(NREM)睡眠期间胶质淋巴清除的最强预测因子。蓝斑的光遗传学刺激引起了血管运动和脑脊液信号的反向变化。此外,刺激动脉振荡可增强脑脊液流入,这表明血管运动起到驱动脑脊液进入大脑的泵的作用。相反,助眠药物唑吡坦抑制了去甲肾上腺素的振荡和胶质淋巴流动,凸显了去甲肾上腺素驱动的血管动力学在大脑清除过程中的关键作用。因此,由去甲肾上腺素波动和血管动力学驱动的NREM睡眠的微结构组织是胶质淋巴清除的关键决定因素。
『总结』 研究发现去甲肾上腺素、脑血容量和脑脊液的同步振荡是NREM睡眠期间大脑胶质淋巴清除的关键因素,揭示了去甲肾上腺素驱动的血管动力学在大脑清除中的重要作用。
【闲叙】

『Abstract』In Huntington’s disease (HD), striatal projection neurons (SPNs) degenerate during midlife; the core biological question involves how the disease-causing DNA repeat (CAG) n in the huntingtin ( HTT ) gene leads to neurodegeneration after decades of biological latency. We developed a single-cell method for measuring this repeat’s length alongside genome-wide RNA expression. We found that the HTT CAG repeat expands somatically from 40–45 to 100–500+ CAGs in SPNs. Somatic expansion from 40 to 150 CAGs had no apparent cell-autonomous effect, but SPNs with 150–500+ CAGs lost positive and then negative features of neuronal identity, de-repressed senescence/apoptosis genes, and were lost. Our results suggest that somatic repeat expansion beyond 150 CAGs causes SPNs to degenerate quickly and asynchronously. We conclude that in HD, at any one time, most neurons have an innocuous but unstable HTT gene and that HD pathogenesis is a DNA process for almost all of a neuron’s life.

『摘要』 在亨廷顿氏病(HD)中,纹状体投射神经元(SPNs)在中年时发生退化;核心生物学问题在于,亨廷顿基因 (HTT) 中的致病DNA重复序列(CAG)n如何在数十年的生物潜伏期后导致神经退行性病变。我们开发了一种单细胞方法,用于测量该重复序列的长度以及全基因组的RNA表达。我们发现,在SPNs中,HTT CAG重复序列在体细胞中从40-45个扩展至100-500+个CAG。体细胞中从40个扩展至150个CAG没有明显细胞自主效应,但具有150-500+个CAG的SPNs会丧失神经元的阳性特征,然后丧失阴性特征,解除对衰老/凋亡基因的抑制,并最终死亡。我们的研究结果表明,体细胞重复序列扩展超过150个CAG会导致SPNs快速且不同步地退化。我们得出结论,在HD中,任何时刻大多数神经元都具有无害但不稳定的HTT基因,并且HD的发病机制几乎是神经元整个生命周期中的DNA过程。
『总结』 研究发现亨廷顿氏病中体细胞CAG重复序列超过150个会导致纹状体投射神经元快速退化,且该病的发病机制是神经元整个生命周期中的DNA过程。
【闲叙】

『Abstract』Zinc is an essential micronutrient that regulates a wide range of physiological processes, most often through zinc binding to protein cysteine residues. Despite being critical for modulation of protein function, the cysteine sites in the majority of the human proteome that are subject to zinc binding remain undefined. Here, we develop ZnCPT, a deep and quantitative mapping of the zinc-binding cysteine proteome. We define 6,173 zinc-binding cysteines, uncovering protein families across major domains of biology that are subject to constitutive or inducible zinc binding. ZnCPT enables systematic discovery of zinc-regulated structural, enzymatic, and allosteric functional domains. On this basis, we identify 52 cancer genetic dependencies subject to zinc binding and nominate malignancies sensitive to zinc-induced cytotoxicity. We discover a mechanism of zinc regulation over glutathione reductase (GSR), which drives cell death in GSR-dependent lung cancers. We provide ZnCPT as a resource for understanding mechanisms of zinc regulation of protein function.

『摘要』 锌是一种必需的微量营养素,可调节广泛的生理过程,最常通过锌与蛋白质半胱氨酸残基的结合来实现。尽管锌对于蛋白质功能的调节至关重要,但在人类蛋白质组中,大部分可能受锌结合的半胱氨酸位点仍不明确。本研究开发了ZnCPT,这是一种深入且定量的锌结合半胱氨酸蛋白质组图谱。我们确定了6173个锌结合半胱氨酸,揭示了生物学主要领域中受组成性或诱导性锌结合的蛋白质家族。ZnCPT能够系统地发现锌调节的结构域、酶功能域和变构功能域。在此基础上,我们确定了52个受锌结合的癌症遗传依赖关系,并指出了对锌诱导的细胞毒性敏感的恶性肿瘤。我们发现了锌对谷胱甘肽还原酶(GSR)的调节机制,该机制可导致GSR依赖性肺癌的细胞死亡。本研究提供ZnCPT作为理解锌调节蛋白质功能机制的资源。
『总结』 本研究开发了ZnCPT方法,揭示了6173个锌结合半胱氨酸,发现了锌调节的新机制,并指出锌结合在癌症中的潜在作用。
【闲叙】

『Abstract』The canonical model of tumor suppressor gene (TSG)-mediated oncogenesis posits that loss of both alleles is necessary for inactivation. Here, through allele-specific analysis of sequencing data from 48,179 cancer patients, we define the prevalence, selective pressure for, and functional consequences of biallelic inactivation across TSGs. TSGs largely assort into distinct classes associated with either pan-cancer (Class 1) or lineage-specific (Class 2) patterns of selection for biallelic loss, although some TSGs are predominantly monoallelically inactivated (Class 3/4). We demonstrate that selection for biallelic inactivation can be utilized to identify driver genes in non-canonical contexts, including among variants of unknown significance (VUSs) of several TSGs such as KEAP1 . Genomic, functional, and clinical data collectively indicate that KEAP1 VUSs phenocopy established KEAP1 oncogenic alleles and that zygosity, rather than variant classification, is predictive of therapeutic response. TSG zygosity is therefore a fundamental determinant of disease etiology and therapeutic sensitivity.

『摘要』 肿瘤抑制基因(TSG)介导的肿瘤发生的经典模型认为,两个等位基因的缺失对于肿瘤抑制基因的失活是必需的。本研究通过对48179名癌症患者的测序数据进行等位基因特异性分析,确定了肿瘤抑制基因中双等位基因失活的流行率、选择压力以及功能后果。肿瘤抑制基因主要分为两类,一类与泛癌症(1类)的双等位基因缺失选择模式相关,另一类与谱系特异性(2类)的选择模式相关,尽管一些肿瘤抑制基因主要以单等位基因失活(3/4类)为主。研究表明,双等位基因失活的选择可用于鉴定非经典情境下的驱动基因,包括几个肿瘤抑制基因(如KEAP1)的未明意义变异(VUS)。基因组、功能和临床数据共同表明,KEAP1的未明意义变异在表型上复制了已确定的KEAP1致癌等位基因,且等位基因状态(而非变异分类)可预测治疗反应。因此,肿瘤抑制基因的等位基因状态是决定疾病病因和治疗敏感性的根本因素。
『总结』 本研究通过大规模数据分析揭示了肿瘤抑制基因双等位基因失活的特征,并指出等位基因状态是预测治疗反应的关键因素。
【闲叙】

『Abstract』In vitro development relies primarily on treating progenitor cells with media-borne morphogens and thus lacks native-like spatial information. Here, we engineer morphogen-secreting organizer cells programmed to self-assemble, via cell adhesion, around mouse embryonic stem (ES) cells in defined architectures. By inducing the morphogen WNT3A and its antagonist DKK1 from organizer cells, we generated diverse morphogen gradients, varying in range and steepness. These gradients were strongly correlated with morphogenetic outcomes: the range of minimum-maximum WNT activity determined the resulting range of anterior-to-posterior (A-P) axis cell lineages. Strikingly, shallow WNT activity gradients, despite showing truncated A-P lineages, yielded higher-resolution tissue morphologies, such as a beating, chambered cardiac-like structure associated with an endothelial network. Thus, synthetic organizer cells, which integrate spatial, temporal, and biochemical information, provide a powerful way to systematically and flexibly direct the development of ES or other progenitor cells in different directions within the morphogenetic landscape.

『摘要』 体外发育主要依赖于用介质传播的形态发生素处理祖细胞,因此缺乏类似原生的空间信息。本研究中,我们设计了能分泌形态发生素的组织者细胞,这些细胞可通过细胞黏附,在特定结构中围绕小鼠胚胎干细胞(ES细胞)进行自组装。我们通过诱导组织者细胞分泌形态发生素WNT3A及其拮抗剂DKK1,生成了范围和陡峭程度各不相同的多种形态发生素梯度。这些梯度与形态发生结果密切相关:WNT活性的最小-最大范围决定了前后(A-P)轴细胞谱系的相应范围。值得注意的是,尽管较浅的WNT活性梯度显示出截断的前后轴谱系,但却产生了更高分辨率的组织形态,如与内皮网络相关的、有搏动的多室心脏样结构。因此,能整合空间、时间和生化信息的合成组织者细胞,为在系统且灵活地指导ES细胞或其他祖细胞在形态发生范围内向不同方向发育提供了一种强有力的方法。
『总结』 本研究设计了能分泌形态发生素的合成组织者细胞,通过形成不同的形态发生素梯度,实现了对小鼠胚胎干细胞等祖细胞发育方向的高分辨率、灵活指导。
【闲叙】

『Abstract』Three proton-sensing G protein-coupled receptors (GPCRs)—GPR4, GPR65, and GPR68—respond to extracellular pH to regulate diverse physiology. How protons activate these receptors is poorly understood. We determined cryogenic-electron microscopy (cryo-EM) structures of each receptor to understand the spatial arrangement of proton-sensing residues. Using deep mutational scanning (DMS), we determined the functional importance of every residue in GPR68 activation by generating ∼9,500 mutants and measuring their effects on signaling and surface expression. Constant-pH molecular dynamics simulations provided insights into the conformational landscape and protonation patterns of key residues. This unbiased approach revealed that, unlike other proton-sensitive channels and receptors, no single site is critical for proton recognition. Instead, a network of titratable residues extends from the extracellular surface to the transmembrane region, converging on canonical motifs to activate proton-sensing GPCRs. Our approach integrating structure, simulations, and unbiased functional interrogation provides a framework for understanding GPCR signaling complexity.

『摘要』 三种质子敏感的G蛋白偶联受体(GPCR)——GPR4、GPR65和GPR68会对细胞外pH值产生响应,进而调节多种生理功能。然而,质子如何激活这些受体,目前尚不清楚。我们通过冷冻电子显微镜(cryo-EM)技术解析了每种受体的结构,从而了解了质子敏感残基的空间排列。利用深度突变扫描(DMS)技术,我们构建了约9500个突变体,并测量了它们对信号传导和表面表达的影响,以此确定了GPR68激活过程中每个残基的功能重要性。恒定pH值分子动力学模拟让我们深入了解了关键残基的构象变化和质子化模式。这种无偏见的方法显示,与其他质子敏感通道和受体不同,质子识别并不依赖于单一的位点。相反,一个由可滴定残基组成的网络从细胞外表面延伸至跨膜区,汇聚于典型基序以激活质子敏感的GPCR。我们这种结合结构解析、模拟和无偏见功能分析的综合方法为理解GPCR信号传导的复杂性提供了一个框架。
『总结』 本研究通过结构解析、模拟和无偏见突变扫描,揭示了质子敏感GPCR的激活机制,发现其依赖于一个由可滴定残基组成的网络,而非单一识别位点。
【闲叙】

『Abstract』Despite recent advances in imaging- and antibody-based methods, achieving in-depth, high-resolution protein mapping across entire tissues remains a significant challenge in spatial proteomics. Here, we present parallel-flow projection and transfer learning across omics data (PLATO), an integrated framework combining microfluidics with deep learning to enable high-resolution mapping of thousands of proteins in whole tissue sections. We validated the PLATO framework by profiling the spatial proteome of the mouse cerebellum, identifying 2,564 protein groups in a single run. We then applied PLATO to rat villus and human breast cancer samples, achieving a spatial resolution of 25 μm and uncovering proteomic dynamics associated with disease states. This approach revealed spatially distinct tumor subtypes, identified key dysregulated proteins, and provided novel insights into the complexity of the tumor microenvironment. We believe that PLATO represents a transformative platform for exploring spatial proteomic regulation and its interplay with genetic and environmental factors.

『摘要』 尽管基于成像和抗体的方法近期取得了进展,但在空间蛋白质组学中,实现对整个组织进行深入、高分辨率的蛋白质图谱绘制仍然是一项重大挑战。本文提出了跨组学数据的并行流投影和迁移学习(PLATO)框架,该框架将微流控技术与深度学习相结合,能够对全组织切片中的数千种蛋白质进行高分辨率图谱绘制。我们通过绘制小鼠小脑的空间蛋白质组图谱对PLATO框架进行了验证,在一次运行中鉴定出2564个蛋白质组。随后,我们将PLATO应用于大鼠肠绒毛和人类乳腺癌样本,实现了25微米的空间分辨率,并揭示了与疾病状态相关的蛋白质组动态变化。该方法揭示了空间上不同的肿瘤亚型,鉴定出了关键失调蛋白质,并为肿瘤微环境的复杂性提供了新见解。我们认为,PLATO是一个用于探索空间蛋白质组调控及其与遗传和环境因素相互作用的变革性平台。
『总结』 PLATO框架结合微流控和深度学习技术,实现了对全组织切片中数千种蛋白质的高分辨率图谱绘制,为空间蛋白质组学研究提供了变革性平台。
【闲叙】

『Abstract』Understanding mammalian preimplantation development, particularly in humans, at the proteomic level remains limited. Here, we applied our comprehensive solution of ultrasensitive proteomic technology to measure the proteomic profiles of oocytes and early embryos and identified nearly 8,000 proteins in humans and over 6,300 proteins in mice. We observed distinct proteomic dynamics before and around zygotic genome activation (ZGA) between the two species. Integrative analysis with translatomic data revealed extensive divergence between translation activation and protein accumulation. Multi-omic analysis indicated that ZGA transcripts often contribute to protein accumulation in blastocysts. Using mouse embryos, we identified several transcriptional regulators critical for early development, thereby linking ZGA to the first lineage specification. Furthermore, single-embryo proteomics of poor-quality embryos from over 100 patient couples provided insights into preimplantation development failure. Our study may contribute to reshaping the framework of mammalian preimplantation development and opening avenues for addressing human infertility.

『摘要』 对哺乳动物(尤其是人类)着床前发育的蛋白质组水平研究仍然有限。本研究采用超灵敏蛋白质组技术综合解决方案,测量了卵母细胞和早期胚胎的蛋白质组特征,在人类中鉴定出近8000种蛋白质,在小鼠中鉴定出6300多种蛋白质。我们观察到两种物种在受精后基因组激活(zygotic genome activation,ZGA)前后表现出不同的蛋白质组动态。与翻译组数据的综合分析显示,翻译激活和蛋白质积累之间存在广泛差异。多组学分析表明,ZGA转录本经常促进囊胚中的蛋白质积累。利用小鼠胚胎,我们确定了几个对早期发育至关重要的转录调控因子,从而将ZGA与首次谱系特化联系起来。此外,对来自100多对患者夫妇的低质量胚胎进行的单胚胎蛋白质组学研究为着床前发育失败提供了见解。本研究或有助于重塑哺乳动物着床前发育的框架,并为解决人类不育问题开辟新途径。
『总结』 本研究通过超灵敏蛋白质组技术揭示了人类和小鼠着床前发育的蛋白质组特征,并发现了ZGA在蛋白质积累和早期发育中的关键作用。
【闲叙】

『Abstract』The detection of molecular patterns associated with invading pathogens is a hallmark of innate immune systems. Prokaryotes deploy sophisticated host defense mechanisms in innate anti-phage immunity. Shedu is a single-component defense system comprising a putative nuclease SduA. Here, we report cryoelectron microscopy (cryo-EM) structures of apo- and double-stranded DNA (dsDNA)-bound tetrameric SduA assemblies, revealing that the N-terminal domains of SduA form a clamp that recognizes free DNA ends. End binding positions the DNA over the PD-(D/E)XK nuclease domain, resulting in dsDNA nicking at a fixed distance from the 5′ end. The end-directed DNA nicking activity of Shedu prevents propagation of linear DNA in vivo . Finally, we show that phages escape Shedu immunity by suppressing their recombination-dependent DNA replication pathway. Taken together, these results define the antiviral mechanism of Shedu systems, underlining the paradigm that recognition of pathogen-specific nucleic acid structures is a conserved feature of innate immunity across all domains of life.

『摘要』 先天免疫系统的一个标志是能够检测到与入侵病原体相关的分子模式。原核生物在先天抗噬菌体免疫中部署了复杂的宿主防御机制。Shedu是一种单组分防御系统,包含一个假定的核酸酶SduA。在此,我们报告了非结合态和结合双链DNA(dsDNA)的四聚体SduA组装体的冷冻电子显微镜(cryo-EM)结构,揭示了SduA的N端结构域形成一个识别游离DNA末端的夹子。末端结合使DNA定位在PD-(D/E)XK核酸酶结构域上,从而在距5′端固定距离处产生dsDNA缺口。Shedu的末端导向DNA缺口活性可阻止线性DNA在体内传播。最后,我们发现噬菌体通过抑制其重组依赖性DNA复制途径来逃避Shedu免疫。综上所述,这些研究结果阐明了Shedu系统的抗病毒机制,强调了识别病原体特异性核酸结构是所有生命领域先天免疫的保守特征这一范式。
『总结』 研究发现Shedu系统通过识别DNA末端并产生缺口来阻止噬菌体DNA传播,揭示了原核生物中一种保守的抗病毒免疫机制。
【闲叙】

『Abstract』Replication and genome encapsidation of many negative-sense RNA viruses take place in virus-induced membraneless organelles termed viral factories (VFs). Although liquid properties of VFs are believed to control the transition from genome replication to nucleocapsid (NC) assembly, VF maturation and interactions with the cellular environment remain elusive. Here, we apply in situ cryo-correlative light and electron tomography to follow NC assembly and changes in VF morphology and their liquid properties during Ebola virus infection. We show that viral NCs transition from loosely packed helical assemblies in early VFs to compact cylinders that arrange into highly organized parallel bundles later in infection. Early VFs associate with intermediate filaments and are devoid of other host material but become progressively accessible to cellular components. Our data suggest that this process is coupled to VF solidification, loss of sphericity, and dispersion and promotes cytoplasmic exposure of NCs to facilitate their transport to budding sites.

『摘要』 许多负链RNA病毒的复制和基因组封装发生在病毒诱导的无膜细胞器即病毒工厂(VFs)中。尽管人们认为病毒工厂的液相特性控制着从基因组复制到核衣壳(NC)组装的转变,但病毒工厂的成熟及其与细胞环境的相互作用仍不清楚。本研究应用原位冷冻相关光电断层扫描技术,追踪埃博拉病毒感染过程中核衣壳的组装、病毒工厂形态的变化及其液相特性。我们的研究表明,在感染初期,病毒核衣壳在病毒工厂中呈松散排列的螺旋状结构,而后逐渐转变为排列成高度有序平行束的紧凑圆柱体。早期的病毒工厂与中间纤维相关,且不含有其他宿主物质,但随着时间的推移,逐渐可被细胞组分接触。我们的数据表明,这一过程与病毒工厂固化、球形丧失及分散有关,并促进了核衣壳暴露于细胞质中,从而有利于它们被运输到出芽位点。
『总结』 本研究揭示了埃博拉病毒感染过程中病毒核衣壳在病毒工厂内的组装过程及病毒工厂形态和液相特性的变化,并发现这些变化促进了核衣壳的运输。
【闲叙】

『Abstract』During early mammalian development, the endoderm germ layer forms the foundation of the respiratory and digestive systems through complex patterning. This intricate process, guided by a series of cell fate decisions, remains only partially understood. Our study introduces innovative genetic tracing codes for 14 distinct endodermal regions using novel mouse strains. By integrating high-throughput and high-precision single-cell RNA sequencing with sophisticated imaging, we detailed the spatiotemporal and genetic lineage differentiation of the endoderm at single-cell resolution. We discovered an unexpected multipotentiality within early endodermal regions, allowing differentiation into various organ primordia. This research illuminates the complex and underestimated phenomenon where endodermal organs develop from multiple origins, prompting a reevaluation of traditional differentiation models. Our findings advance understanding in developmental biology and have significant implications for regenerative medicine and the development of advanced organoid models, providing insights into the intricate mechanisms that guide organogenesis.

『摘要』 在哺乳动物早期发育过程中,内胚层通过复杂的模式化过程形成呼吸系统和消化系统的基础。这一由一系列细胞命运决定所指导的复杂过程,目前仍只是部分为人所知。我们的研究利用新型小鼠品系,为14个不同的内胚层区域引入了创新的遗传追踪代码。通过结合高通量、高精度的单细胞RNA测序与精密成像技术,我们详细阐述了内胚层在单细胞分辨率下的时空和遗传谱系分化。我们发现早期内胚层区域具有一种出乎意料的多能性,可以分化成各种器官原基。本研究揭示了内胚层器官从多个起源发育而来的复杂且被低估的现象,促使人们重新评估传统的分化模型。我们的研究结果推进了对发育生物学的理解,对再生医学和高级类器官模型的开发具有重要意义,为引导器官生成的复杂机制提供了见解。
『总结』 本研究通过新型遗传追踪和单细胞测序技术,揭示了哺乳动物早期内胚层发育的复杂性和多能性,对发育生物学和医学领域有重要影响。
【闲叙】

『Abstract』In a genome-wide association study (GWAS) meta-analysis of 688,808 individuals with major depression (MD) and 4,364,225 controls from 29 countries across diverse and admixed ancestries, we identify 697 associations at 635 loci, 293 of which are novel. Using fine-mapping and functional tools, we find 308 high-confidence gene associations and enrichment of postsynaptic density and receptor clustering. A neural cell-type enrichment analysis utilizing single-cell data implicates excitatory, inhibitory, and medium spiny neurons and the involvement of amygdala neurons in both mouse and human single-cell analyses. The associations are enriched for antidepressant targets and provide potential repurposing opportunities. Polygenic scores trained using European or multi-ancestry data predicted MD status across all ancestries, explaining up to 5.8% of MD liability variance in Europeans. These findings advance our global understanding of MD and reveal biological targets that may be used to target and develop pharmacotherapies addressing the unmet need for effective treatment.

『摘要』 在一项涉及来自29个国家、拥有不同和混合血统的688,808名重度抑郁症(MD)患者和4,364,225名对照者的全基因组关联研究(GWAS)荟萃分析中,我们发现了635个位点上的697个关联,其中293个是新发现的。通过精细定位和功能性工具,我们确定了308个高置信度基因关联,并发现突触后致密物和受体聚集成簇。利用单细胞数据进行神经细胞类型富集分析发现,兴奋性神经元、抑制性神经元和中棘神经元以及杏仁核神经元在小鼠和人类单细胞分析中均有所涉及。这些关联在抗抑郁药物靶点中有所富集,并为药物重新利用提供了潜在机会。使用欧洲或多血统数据训练的基因组多基因评分可以预测所有血统人群的MD状态,解释了欧洲人MD易感性变异高达5.8%。这些发现加深了我们对MD的全球理解,并揭示了可用于针对和开发解决有效治疗未满足需求的药物疗法的生物学靶点。
『总结』 该研究通过GWAS荟萃分析发现了与重度抑郁症相关的新遗传关联和基因靶点,为药物开发和重新利用提供了线索,并解释了MD的部分遗传易感性。
【闲叙】

『Abstract』Protein assembly into functional complexes is critical to life’s processes. While complex assembly is classically described as occurring between fully synthesized proteins, recent work showed that co-translational assembly is prevalent in human cells. However, the biological basis for the existence of this process and the identity of protein pairs that assemble co-translationally remain unknown. We show that co-translational assembly is governed by structural characteristics of complexes and involves mutually stabilized subunits. Accordingly, co-translationally assembling subunits are unstable in isolation and exhibit synchronized proteostasis with their partner. By leveraging structural signatures and AlphaFold2-based predictions, we accurately predicted co-translational assembly, including pair identities, at proteome scale and across species. We validated our predictions by ribosome profiling, stoichiometry perturbations, and single-molecule RNA-fluorescence in situ hybridization (smFISH) experiments that revealed co-localized mRNAs. This work establishes a fundamental connection between protein structure and the translation process, highlighting the overarching impact of three-dimensional structure on gene expression, mRNA localization, and proteostasis.

『摘要』 蛋白质组装成功能性复合物对生命过程至关重要。尽管传统上认为复合物的组装发生在完全合成的蛋白质之间,但最近的研究表明,共翻译组装在人类细胞中普遍存在。然而,这一过程存在的生物学基础以及共翻译组装的蛋白质对的身份仍然未知。我们的研究表明,共翻译组装受复合物结构特征的调控,并涉及相互稳定的亚基。因此,共翻译组装的亚基在单独存在时不稳定,并与其伴侣表现出同步的蛋白质稳态。通过利用结构特征和基于AlphaFold2的预测,我们在蛋白质组范围和跨物种水平上准确预测了共翻译组装,包括蛋白质对的身份。我们通过核糖体分析、化学计量扰动和单分子RNA荧光原位杂交(smFISH)实验验证了我们的预测,这些实验揭示了共定位的mRNA。本研究建立了蛋白质结构与翻译过程之间的基本联系,强调了三维结构对基因表达、mRNA定位和蛋白质稳态的广泛影响。
『总结』 本研究发现共翻译组装受复合物结构调控,利用结构特征和AlphaFold2预测可准确预测该过程,揭示了蛋白质结构与翻译过程的紧密联系。
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『Abstract』Animals have evolved pH-sensing membrane receptors, such as G-protein-coupled receptor 4 (GPR4), to monitor pH changes related to their physiology and generate adaptive reactions. However, the evolutionary trajectory and structural mechanism of proton sensing by GPR4 remain unresolved. Here, we observed a positive correlation between the optimal pH of GPR4 activity and the blood pH range across different species. By solving 7-cryoelectron microscopy (cryo-EM) structures of Xenopus tropicalis GPR4 (xtGPR4) and Mus musculus GPR4 (mmGPR4) under varying pH conditions, we identified that protonation of H and H enabled polar network establishment and tighter association between the extracellular loop 2 (ECL2) and 7 transmembrane (7TM) domain, as well as a conserved propagating path, which are common mechanisms underlying protonation-induced GPR4 activation across different species. Moreover, protonation of distinct extracellular H contributed to the more acidic optimal pH range of xtGPR4. Overall, our study revealed common and distinct mechanisms of proton sensing by GPR4, from a structural, functional, and evolutionary perspective.

『摘要』 动物进化出了pH值感应膜受体,如G蛋白偶联受体4(GPR4),以监测与生理相关的pH值变化并产生适应性反应。然而,GPR4对质子的感应的进化轨迹和结构机制仍不清楚。本研究发现GPR4活性最适pH值与不同物种的血液pH值范围之间存在正相关关系。我们通过解析不同pH条件下热带爪蟾GPR4(xtGPR4)和小家鼠GPR4(mmGPR4)的7-冷冻电子显微镜(cryo-EM)结构发现,H和H的质子化促进了极性网络的形成,并使细胞外环2(ECL2)和7次跨膜(7TM)结构域之间结合更紧密,还形成了一个保守的传播路径;这些是不同物种中质子化诱导GPR4活化的共同机制。此外,细胞外不同H的质子化导致了xtGPR4的最适pH值范围更偏酸性。总体而言,本研究从结构、功能和进化的角度揭示了GPR4对质子的感应的共同和独特机制。
『总结』 本研究揭示了GPR4对质子感应的共同和独特机制,有助于理解不同物种中GPR4的进化、结构和功能。
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『Abstract』Nipah virus (NiV) is a bat-borne, zoonotic RNA virus that is highly pathogenic in humans. The NiV polymerase, which mediates viral genome replication and mRNA transcription, is a promising drug target. We determined the cryoelectron microscopy (cryo-EM) structure of the NiV polymerase complex, comprising the large protein (L) and phosphoprotein (P), and performed structural, biophysical, and in-depth functional analyses of the NiV polymerase. The L protein assembles with a long P tetrameric coiled-coil that is capped by a bundle of ⍺-helices that we show are likely dynamic in solution. Docking studies with a known L inhibitor clarify mechanisms of antiviral drug resistance. In addition, we identified L protein features that are required for both transcription and RNA replication and mutations that have a greater impact on RNA replication than on transcription. Our findings have the potential to aid in the rational development of drugs to combat NiV infection.

『摘要』 尼帕病毒(NiV)是一种蝙蝠传播的、人畜共患的RNA病毒,对人类具有高度致病性。NiV聚合酶介导病毒基因组复制和mRNA转录,是一个有前景的药物靶点。我们利用冷冻电子显微镜(cryo-EM)确定了NiV聚合酶复合物的结构,该复合物由大蛋白(L)和磷蛋白(P)组成,并对NiV聚合酶进行了结构、生物物理和深入的功能分析。L蛋白与一个长的P四聚体卷曲螺旋结合,该螺旋由一个α-螺旋束封端,我们在研究中表明该螺旋束在溶液中可能是动态的。通过与已知L蛋白抑制剂的对接研究,我们阐明了抗病毒药物的耐药机制。此外,我们还发现了L蛋白在转录和RNA复制中均需要的特征,以及那些对RNA复制的影响比对转录的影响更大的突变。我们的研究结果有可能为合理开发抗NiV感染药物提供帮助。
『总结』 本研究通过冷冻电镜等方法解析了NiV聚合酶的结构与功能,为开发抗NiV药物提供了理论基础。
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『Abstract』Structural maintenance of chromosomes (SMC) complexes organize the genome via DNA loop extrusion. Although some SMCs were reported to do so symmetrically, reeling DNA from both sides into the extruded DNA loop simultaneously, others perform loop extrusion asymmetrically toward one direction only. The mechanism underlying this variability remains unclear. Here, we examine the directionality of DNA loop extrusion by SMCs using in vitro single-molecule experiments. We find that cohesin and SMC5/6 do not reel in DNA from both sides, as reported before, but instead extrude DNA asymmetrically, although the direction can switch over time. Asymmetric DNA loop extrusion thus is the shared mechanism across all eukaryotic SMC complexes. For cohesin, direction switches strongly correlate with the turnover of the subunit NIPBL, during which DNA strand switching may occur. Apart from expanding by extrusion, loops frequently diffuse and shrink. The findings reveal that SMCs, surprisingly, can switch directions.

『摘要』 结构维持染色体(SMC)复合物通过DNA环挤出机制来组织基因组。虽然已有报道指出,一些SMC能够对称地进行DNA环挤出,即从两侧同时将DNA卷入挤出的DNA环中,但另一些SMC则仅向一个方向不对称地进行环挤出。这种变异性的潜在机制尚不清楚。本研究通过体外单分子实验,探究了SMC进行DNA环挤出的方向性。我们发现,与之前报道的不同,凝聚素和SMC5/6并不是从两侧同时卷入DNA,而是进行不对称的DNA挤出,尽管挤出方向会随时间而改变。因此,不对称DNA环挤出是所有真核生物SMC复合物共有的机制。对于凝聚素而言,方向的改变与亚单位NIPBL的转换密切相关,在这一过程中可能发生DNA链的转换。除了通过挤出而扩展外,环还会频繁地扩散和收缩。这些发现揭示了一个令人惊讶的事实:SMC可以改变挤出方向。
『总结』 研究发现SMC复合物进行不对称DNA环挤出,且方向可随时间改变,这是所有真核生物SMC共有的机制。
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