前沿速递 | NCS 集萃: 2025-05-16 期 [Up]

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『Abstract』Abstract Two-dimensional strongly interacting electrons crystalize into a solid phase known as the Wigner crystal at low densities and form a Fermi liquid at high densities. At intermediate densities, the two-dimensional solid evolves into a strongly correlated liquid phase around a critical density. We observed this quantum melting of a disordered Wigner solid in bilayer molybdenum diselenide (MoSe 2 ) using a noninvasive scanning tunneling microscopy imaging technique. At low densities, the Wigner solid forms nanocrystalline domains pinned by local disorder. It exhibits a quantum densification behavior with increased densities in the solid phase. Above a threshold density, the Wigner solid melts locally and enters a mixed phase in which solid and liquid regions coexist. The liquid regions expand and form a percolation network at even higher densities.

『摘要』 在低密度下,二维强相互作用电子会结晶成称为魏格纳晶体的固相,而在高密度下则形成费米液体。在中等密度下,二维固体在临界密度附近演变成强相关液体相。我们使用无创扫描隧道显微镜成像技术,在双层二硒化钼(MoSe2)中观察到了这种无序魏格纳固体的量子熔化现象。在低密度下,魏格纳固体形成由局部无序固定的纳米晶体域,在固体相中随着密度的增加而表现出量子致密化行为。当密度超过阈值时,魏格纳固体局部熔化并进入固液共存的混合相。随着密度的进一步增加,液体区域扩张并形成渗流网络。
『总结』 研究通过无创扫描隧道显微镜成像技术观察到二维强相互作用电子在双层二硒化钼中随密度变化展现从魏格纳固体到费米液体的量子相变过程。
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『Abstract』Abstract How astrocytes regulate neuronal circuits is a fundamental question in neurobiology. Specifically, how astrocytes respond to different neurotransmitters in vivo and how they affect downstream circuit modulation are questions that remain to be fully elucidated. Here, we report a mechanism in Drosophila by which G protein–coupled adrenergic signaling in astrocytes can control—or “gate”—their ability to respond to other neurotransmitters. Further, we show that manipulating this pathway potently regulates neuronal circuit activity and animal behavior. This gating mechanism is conserved in cultured primary mammalian astrocytes, suggesting that it might be an ancient feature of astrocyte circuit function. Our work establishes a mechanism by which astrocytes dynamically respond to and modulate neuronal activity in different brain regions and in different behavioral states.

『摘要』 星形胶质细胞如何调节神经元回路是神经生物学中的一个基本问题。具体而言,星形胶质细胞在体内如何对不同神经递质作出反应以及它们如何影响下游回路调节,这些问题仍有待充分阐明。本文报告了在果蝇中的一种机制,通过这种机制,星形胶质细胞中的G蛋白偶联肾上腺素能信号传导可以控制或“调控”星形胶质细胞对其他神经递质的反应能力。此外,我们的研究表明,调控该通路可有效调节神经元回路活动和动物行为。这种调控机制在培养的原代哺乳动物星形胶质细胞中也是保守的,表明它可能是星形胶质细胞回路功能的一个古老特征。我们的研究揭示了一种机制,即星形胶质细胞可动态响应并调节不同脑区和不同行为状态下的神经元活动。
『总结』 本研究发现星形胶质细胞通过G蛋白偶联肾上腺素能信号传导机制调控其对神经递质的反应,该机制在不同物种中保守,对神经元活动和动物行为有重要影响。
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『Abstract』Abstract Mountain biodiversity reorganizes rapidly as species shift upslope to track temperatures. Pervasive species redistribution poses substantial threats to mountain ecosystems, a phenomenon sometimes described as an “escalator to extinction,” primarily through mountaintop extinctions, range shift gaps (i.e., rapid shifts of suitable temperatures getting ahead of narrow-range species’ upper limits), and lowland biodiversity attrition, yet empirical evidence remains scarce. In this study, our analysis of 8800 records of historical and modern elevational range limits for 440 animal and 1629 plant species revealed little evidence supporting the proposed threats. Observed changes largely fell within random expectations, accounting for geometric constraints. Although delayed mountaintop extinctions point to accumulating extinction debt, concurrent range expansions of both narrow-range and lowland species suggest thermal niche underfilling, processes that collectively drive biotic homogenization across biologically complex mountain ecosystems.

『摘要』 随着物种向山坡上移动以追踪适宜温度,山地生物多样性正在快速重组。物种的大规模重新分布对山地生态系统构成了重大威胁,这一现象有时被称为“通向灭绝的自动扶梯”,主要通过山顶物种灭绝、分布区转移缺口(即适宜温度快速变化超过了分布区狭窄物种的上限)和低地生物多样性减少等方式,但目前仍缺乏实证证据。在这项研究中,我们分析了440种动物和1629种植物的历史和现代海拔分布范围记录的8800个数据,结果发现几乎没有证据支持上述威胁。考虑到几何约束因素,观察到的变化大多在随机预期范围内。虽然山顶物种灭绝有所延迟,表明存在灭绝债务累积,但分布区狭窄物种和低地物种的同时扩张表明热量生态位未充分填充,这些过程共同推动了生物结构复杂的山地生态系统中的生物同质化。
『总结』 研究表明,尽管存在物种重新分布,但目前对山地生态系统所谓“通向灭绝的自动扶梯”威胁的实证证据不足,观察到的变化多为随机且受几何约束影响。
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『Abstract』Abstract Programmable gene integration in human cells has the potential to enable mutation-agnostic treatments for loss-of-function genetic diseases and facilitate many applications in the life sciences. CRISPR-associated transposases (CASTs) catalyze RNA-guided DNA integration but thus far demonstrate minimal activity in human cells. Using phage-assisted continuous evolution (PACE), we generated CAST variants with >200-fold average improved integration activity. The evolved CAST system (evoCAST) achieves ~10 to 30% integration efficiencies of kilobase-size DNA cargoes in human cells across 14 tested genomic target sites, including safe harbor loci, sites used for immunotherapy, and genes implicated in loss-of-function diseases, with undetected indels and low levels of off-target integration. Collectively, our findings establish a platform for the laboratory evolution of CASTs and advance a versatile system for programmable gene integration in living systems.

『摘要』 在人类细胞中,可编程基因整合有可能为功能丧失性遗传病提供与突变无关的治疗方法,并促进生命科学领域的诸多应用。CRISPR相关转座酶(CAST)可催化RNA引导的DNA整合,但在人类细胞中迄今为止表现出的活性极低。我们利用噬菌体辅助连续进化(PACE)技术,生成了CAST变体,其平均整合活性提高了200倍以上。进化后的CAST系统(evoCAST)在14个经过测试的人类细胞基因组靶位点(包括安全港位点、免疫治疗所用位点和功能丧失性疾病相关基因)上实现了千碱基大小DNA货物的~10%至30%的整合效率,未检测到插入或缺失,且脱靶整合水平较低。总体而言,我们的研究结果为CAST的实验室进化建立了一个平台,并为活体系中的可编程基因整合提供了一个多功能系统。
『总结』 研究通过噬菌体辅助连续进化提高了CRISPR相关转座酶的活性,实现了在人类细胞中高效、精准的可编程基因整合。
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『Abstract』Abstract Bats are important reservoirs of zoonotic pathogens, but suitable model systems for comprehensively exploring host-pathogen interactions and assessing spillover risks remain limited. To address this gap, we developed a collection of bat organoid models spanning five species and four organ types. This multispecies, multiorgan organoid panel showed species- and tissue-specific replication patterns for several viruses, offering robust pathophysiological models for studying respiratory, renal, and enteric zoonotic viruses. Using this platform, we successfully isolated and characterized bat-borne mammalian orthoreoviruses and paramyxoviruses, demonstrating the utility of these organoid panels for virome surveillance. Furthermore, we successfully tested known antiviral drugs for their efficacy against bat virus isolates.

『摘要』 蝙蝠是动物源性病原体的重要宿主,但用于全面探索宿主-病原体相互作用和评估溢出风险的合适模型系统仍然有限。为填补这一空白,本研究团队开发了涵盖五种蝙蝠和四种器官类型的蝙蝠类器官模型集合。这种多物种、多器官的类器官面板显示了多种病毒在物种和组织特异性的复制模式,为研究呼吸道、肾脏和肠道动物源性病毒提供了强有力的病理生理模型。利用该平台,研究团队成功分离并鉴定了蝙蝠携带的哺乳动物正呼肠孤病毒和副黏病毒,证明了这些类器官面板在病毒组监测中的实用性。此外,研究团队还成功测试了已知抗病毒药物对蝙蝠病毒分离株的疗效。
『总结』 本研究开发了涵盖多种蝙蝠和器官类型的类器官模型,为病毒研究和抗病毒药物测试提供了有力工具。
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『Abstract』Abstract Both neurons and glia communicate through diffusible neuromodulators; however, how neuron-glial interactions in such neuromodulatory networks influence circuit computation and behavior is unclear. During futility-induced behavioral transitions in the larval zebrafish, the neuromodulator norepinephrine (NE) drives fast excitation and delayed inhibition of behavior and circuit activity. We found that astroglial purinergic signaling implements the inhibitory arm of this motif. In larval zebrafish, NE triggers astroglial release of adenosine triphosphate (ATP), extracellular conversion of ATP into adenosine, and behavioral suppression through activation of hindbrain neuronal adenosine receptors. Our results suggest a computational and behavioral role for an evolutionarily conserved astroglial purinergic signaling axis in NE-mediated behavioral and brain state transitions and position astroglia as important effectors in neuromodulatory signaling.

『摘要』 神经元和胶质细胞都通过可扩散的神经调节剂进行通信;然而,这类神经调节网络中神经元-胶质细胞的相互作用如何影响环路计算和行为尚不清楚。在幼斑马鱼由饥饿诱导的行为转变过程中,神经调节剂去甲肾上腺素(NE)驱动行为和环路活动的快速兴奋和延迟抑制。本研究发现星形胶质细胞的嘌呤能信号传导实现了这一基序的抑制部分。在幼斑马鱼中,NE触发星形胶质细胞释放三磷酸腺苷(ATP),ATP在细胞外转化为腺苷,并通过激活后脑神经元腺苷受体来抑制行为。研究结果提示,在去甲肾上腺素介导的行为和脑状态转变过程中,进化上保守的星形胶质细胞嘌呤能信号传导轴在计算和行为上发挥作用,并表明星形胶质细胞是神经调节信号传导中的重要效应器。
『总结』 研究表明,星形胶质细胞的嘌呤能信号在去甲肾上腺素介导的幼斑马鱼行为和脑状态转变中发挥重要作用。
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『Abstract』Abstract Brazil, the largest Latin American country, is underrepresented in genomic research despite boasting the world’s largest recently admixed population. In this study, we generated 2723 high-coverage whole-genome sequences from the Brazilian population, including urban, rural, and riverine communities representing diverse ethnic backgrounds. We reveal the impressive genomic diversity of Brazilians, identifying >8 million previously unknown variants, including 36,637 predicted deleterious and potentially affecting population health. We found a positive correlation between these deleterious variants and ancestry. Brazilian genomes are a global haplotype mosaic shaped by nonrandom mating, with peak admixture in the 18th and 19th centuries. Within this diversity, ancestry-specific haplotypes exhibit an uneven spatiotemporal distribution. We also identified putatively selected genes in this diverse population, primarily linked to fertility, immune response, and metabolic traits.

『摘要』 巴西是拉丁美洲最大的国家,尽管拥有世界上最大规模的近期混血人口,但在基因组研究中的代表性却不足。在本研究中,我们从巴西人口中生成了2723个高覆盖率的全基因组序列,包括代表不同种族背景的城市、农村和河边社区。我们揭示了巴西人令人印象深刻的基因组多样性,发现了超过800万个先前未知的变异,其中包括36637个预测为有害且可能影响人口健康的变异。我们发现这些有害变异与祖先之间存在正相关关系。巴西人的基因组是一个由非随机交配形成的全球单倍型镶嵌体,混血高峰出现在18世纪和19世纪。在这种多样性中,特定祖先的单倍型呈现出不均匀的时空分布。我们还在这个多样化的人群中发现了可能受到选择的基因,主要与生育能力、免疫反应和代谢特征相关。
『总结』 本研究揭示了巴西人口的基因组多样性,发现了大量新的基因变异,并分析了这些变异与祖先的关系以及可能受到选择的基因。
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『Abstract』Abstract The regulation of G protein–coupled receptor signaling by different orthosteric ligands is thought to occur through shifts in dynamically interconverting, conformational distributions. Such changes in dynamical distributions have been detected so far only by very sparse, often non-native experimental probes at low resolution. Using a recently developed paramagnetic nuclear magnetic resonance (NMR) method, we could assign and follow 81 H- N NMR correlations in the β 1 -adrenergic receptor β 1 AR at ambient conditions in response to various orthosteric ligands in the absence or presence of a G protein–mimicking nanobody. The comparison reveals the dynamics and mechanism of the central, highly conserved xWIPF 3 motif, contiguous regions of rigid and loose conformational coupling separated by conserved prolines during signal transmission, and the plasticity of the intracellular face in response to transducer binding.

『摘要』 正文:G蛋白偶联受体信号转导的不同正位配体的调节被认为是通过动态相互转化、构象分布的变化来实现的。迄今为止,这种动态分布的变化只能通过极少数且通常是非天然的、低分辨率的实验探针来检测。我们使用最近开发的顺磁核磁共振(NMR)方法,在没有或有G蛋白模拟纳米抗体的情况下,能够在环境温度下跟踪β1-肾上腺素能受体(β1AR)中81个H-N核磁共振相关性的变化以响应不同的正位配体。通过比较,我们揭示了中心高度保守的xWIPF3基序的动力学和机制,信号转导过程中被保守的脯氨酸分隔开的刚性和松散构象偶联的连续区域,以及胞内面在响应传感器结合时的可塑性。
『总结』 利用顺磁核磁共振技术,我们揭示了β1-肾上腺素能受体中不同正位配体调节下的构象分布变化及其信号转导机制。
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『Abstract』Abstract Climate affects habitat, food availability, and the movement and sustainability of all life. In this work, we apply Indigenous and Western scientific methods, including genomics and isotope profiling, on fossils from across Beringia to explore the effect of climate change on horses. We find that Late Pleistocene horses from Alaska and northern Yukon are related to populations from Eurasia and crossed the Bering land bridge multiple times during the last glacial interval. We also find deeply divergent lineages north and south of the American ice sheets that genetically influenced populations across Beringia and into Eurasia. As climate warmed and horses entered the ice-free corridor connecting Beringia and midcontinental America, restricted mobility and food availability impeded population growth. Our combined Western and Indigenous framework offers critical guidance for wildlife conservation amid ongoing climate change.

『摘要』 气候影响着栖息地、食物获取,以及所有生物的活动和存续。在这项研究中,我们对来自整个白令吉亚(Beringia)的化石应用了原住民和西方的科学方法,包括基因组学和同位素分析,以探索气候变化对马的影响。我们发现,阿拉斯加和北育空地区的更新世晚期马与欧亚大陆的种群有亲缘关系,并在上一个冰河时代多次穿越白令陆桥。我们还发现,美洲冰盖南北两侧的种群谱系存在巨大差异,这些差异在遗传学上对白令吉亚乃至欧亚大陆的种群都产生了影响。随着气候变暖,马匹进入连接白令吉亚和美国中西部的无冰走廊,但活动范围受限和食物获取困难阻碍了种群增长。我们结合西方和原住民知识框架的研究为当前气候变化下的野生动物保护提供了重要指导。
『总结』 本研究结合原住民和西方科学方法,揭示了气候变化对马种群的影响,强调了在气候变化背景下结合不同知识体系进行野生动物保护的重要性。
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『Abstract』Abstract Genome sequencing of 1537 individuals from 139 ethnic groups reveals the genetic characteristics of understudied populations in North Asia and South America. Our analysis demonstrates that West Siberian ancestry, represented by the Kets and Nenets, contributed to the genetic ancestry of most Siberian populations. West Beringians, including the Koryaks, Inuit, and Luoravetlans, exhibit genetic adaptation to Arctic climate, including medically relevant variants. In South America, early migrants split into four groups—Amazonians, Andeans, Chaco Amerindians, and Patagonians—~13,900 years ago. Their longest migration led to population decline, whereas settlement in South America’s diverse environments caused instant spatial isolation, reducing genetic and immunogenic diversity. These findings highlight how population history and environmental pressures shaped the genetic architecture of human populations across North Asia and South America.

『摘要』 对来自139个民族的1537名个体进行基因组测序,揭示了北亚和南美研究较少的族群的遗传特征。我们的分析表明,以西伯利亚西部的克特人和涅涅茨人为代表的祖先群体对大多数西伯利亚族群的遗传血统有贡献。包括科里亚克人、因纽特人和罗拉韦特兰人在内的西白令海人表现出对北极气候的遗传适应性,包括一些具有医学意义的基因变异。在南美洲,早期移民者在约13900年前分化为四个群体:亚马孙人、安第斯人、查科美洲印第安人和巴塔哥尼亚人。他们耗时最长的迁徙导致了人口减少,而在南美洲多样化的环境中定居则造成了即时的空间隔离,降低了遗传和免疫原性多样性。这些发现揭示了人口历史和环境压力是如何塑造北亚和南美洲人群遗传结构的。
『总结』 通过对北亚和南美多个族群的大规模基因组测序,研究发现人口历史和环境因素对这些地区人群的遗传特征产生了深远影响。
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『Abstract』Abstract Mixing electroactive materials, solid-state electrolytes, and conductive carbon to fabricate composite electrodes is the most practiced but least understood process in all-solid-state batteries, which strongly dictates interfacial stability and charge transport. We report on universal halide segregation at interfaces across various halogen-containing solid-state electrolytes and a family of high-energy chalcogen cathodes enabled by mechanochemical reaction during ultrahigh-speed mixing. Bulk and interface characterizations by multimodal synchrotron x-ray probes and cryo–transmission electron microscopy show that the in situ segregated lithium halide interfacial layers substantially boost effective ion transport and suppress the volume change of bulk chalcogen cathodes. Various all-solid-state lithium-chalcogen cells demonstrate utilization close to 100% and extraordinary cycling stability at commercial-level areal capacities.

『摘要』 在全固态电池中,将电活性材料、固态电解质和导电碳混合以制备复合电极是最常用但最不被理解的过程,这一过程对界面稳定性和电荷传输具有决定性影响。我们报告了在超高速混合过程中,通过机械化学反应在各种含卤素固态电解质和高能量硫族化物阴极之间普遍存在卤素偏析的现象。通过多模式同步加速器X射线探针和冷冻透射电子显微镜对本体和界面进行表征,结果表明,原位偏析的卤化锂界面层显著促进了有效离子传输,并抑制了硫族化物阴极本体的体积变化。各种全固态锂硫族化物电池表现出接近100%的利用率,在商业级面容量下具有非凡的循环稳定性。
『总结』 研究发现,通过机械化学反应在超高速混合过程中,含卤素固态电解质和高能量硫族阴极间普遍存在卤素偏析,这一现象显著提升了全固态锂硫电池性能。
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『Abstract』Abstract Locus ceruleus (LC)–derived norepinephrine (NE) drives network and behavioral adaptations to environmental saliencies by reconfiguring circuit functional connectivity, but the underlying synapse-level mechanisms are elusive. Here, we show that NE remodeling of synaptic function is completely independent from its binding on neuronal receptors. Instead, astrocytic adrenergic receptors and calcium dynamics fully gate the effect of NE on synapses. Additionally, we found that NE suppression of synaptic strength results from an adenosine 5′-triphosphate (ATP)–derived and A1 adenosine receptor–mediated control of presynaptic efficacy. These findings suggest that astrocytes are a core component of neuromodulatory systems and the circuit effector through which NE produces network and behavioral adaptations.

『摘要』 蓝斑(locus ceruleus,LC)衍生的去甲肾上腺素(norepinephrine,NE)通过重新配置回路功能连接来驱动网络和行为对环境显著性的适应,但其潜在的突触层面机制尚不清楚。本研究表明,去甲肾上腺素对突触功能的重塑完全独立于其与神经元受体的结合。相反,星形胶质细胞肾上腺素能受体和钙动态完全掌控了去甲肾上腺素对突触的影响。此外,本研究还发现,去甲肾上腺素对突触强度的抑制作用是由腺苷5'-三磷酸(adenosine 5′-triphosphate,ATP)衍生和A1腺苷受体介导的突触前效能控制所导致的。这些发现表明,星形胶质细胞是神经调节系统的核心组成部分,也是去甲肾上腺素产生网络和行为适应的回路效应器。
『总结』 研究发现去甲肾上腺素通过独立于神经元受体的机制,依赖星形胶质细胞及其钙动态和ATP-A1腺苷受体途径,调节突触功能并驱动网络和行为适应。
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『Abstract』Abstract Latency is a common strategy in a wide range of viral lineages, but its prevalence in giant viruses remains unknown. In this work, we describe a 617–kilo–base pairs integrated giant viral element in the model green alga Chlamydomonas reinhardtii . We resolved the integrated viral genome using long-read sequencing, identified a putative polintovirus-like integrase, and show that viral particles accumulate primarily during the stationary growth phase. A diverse array of viral-encoded selfish genetic elements is expressed during viral activity, including several Fanzor nuclease–encoding transposable elements. In addition, we show that field isolates of Chlamydomonas spp. harbor signatures of endogenous giant viruses related to the C. reinhardtii virus that exhibit similar infection dynamics, suggesting that giant virus latency is prevalent in natural host communities. Our work describes an unusually large temperate virus of a unicellular eukaryote, substantially expanding the scope of cryptic viral infections in the virosphere.

『摘要』 在广泛的病毒谱系中,潜伏是一种常见的策略,但其在巨型病毒中的流行情况尚不清楚。在本研究中,我们在模式绿藻莱茵衣藻中描述了一个617千碱基对的整合巨型病毒元件。我们利用长读长测序技术解析了整合的病毒基因组,鉴定出一种推测的类似多聚整合酶的酶,并发现病毒颗粒主要在稳定生长期积累。在病毒活动期间,会表达多种病毒编码的自私遗传元件,包括几种编码Fanzor核酸酶的转座元件。此外,我们还发现,莱茵衣藻的野外分离株携带了与莱茵衣藻病毒相关的内源性巨型病毒的特征,这些病毒表现出相似的感染动态,这表明巨型病毒的潜伏在自然宿主群体中普遍存在。我们的研究描述了一种单细胞真核生物中异常庞大的温和病毒,极大地扩展了病毒圈中隐匿性病毒感染的范围。
『总结』 研究发现莱茵衣藻中存在一个617千碱基对的整合巨型病毒元件,且巨型病毒潜伏在自然宿主群体中可能普遍存在,这一发现扩展了隐匿性病毒感染的范围。
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『Abstract』Abstract The search for anyons, quasiparticles with fractional charge and exotic exchange statistics, has inspired decades of condensed matter research. Quantum Hall interferometers enable direct observation of the anyon braiding phase through discrete interference phase jumps when the number of encircled localized quasiparticles changes. In this study, we observed this braiding phase in both the filling factor 1/3 and 4/3 fractional quantum Hall states by probing three-state random telegraph noise (RTN) in real time. We found that the observed RTN stems from anyon quasiparticle number n fluctuations, and we reconstructed three Aharonov-Bohm oscillation signals phase shifted by 2π/3, corresponding to the three possible interference branches from braiding around n (mod 3) anyons. Our methods can be readily extended to interference of non-abelian anyons.

『摘要』 数十年来,对任意子(具有分数电荷和奇异交换统计特性的准粒子)的研究一直是凝聚态物理领域的研究热点。量子霍尔干涉仪能够通过离散的干涉相位跃变,直接观察到当环绕的局域准粒子数量变化时任意子的编织相位。在本研究中,我们通过实时监测三态随机电报噪声(RTN),在填充因子为1/3和4/3的分数量子霍尔态中观察到了这种编织相位。我们发现,观察到的RTN源于任意子准粒子数n的波动,并重建了三个相位相差2π/3的阿哈罗诺夫-玻姆振荡信号,对应于环绕n(模3)个任意子时可能产生的三个干涉分支。我们的方法可轻松扩展至非阿贝尔任意子的干涉研究。
『总结』 本研究通过实时监测随机电报噪声,在特定分数量子霍尔态中观察到了任意子的编织相位,并重建了相应的阿哈罗诺夫-玻姆振荡信号。
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『Abstract』Hilbert space dimension is a key resource for quantum information processing . Not only is a large overall Hilbert space an essential requirement for quantum error correction, but a large local Hilbert space can also be advantageous for realizing gates and algorithms more efficiently . As a result, there has been considerable experimental effort in recent years to develop quantum computing platforms using qudits ( d -dimensional quantum systems with d > 2) as the fundamental unit of quantum information . Just as with qubits, quantum error correction of these qudits will be necessary in the long run, but so far, error correction of logical qudits has not been demonstrated experimentally. Here we report the experimental realization of an error-corrected logical qutrit ( d = 3) and ququart ( d = 4), which was achieved with the Gottesman–Kitaev–Preskill bosonic code . Using a reinforcement learning agent , we optimized the Gottesman–Kitaev–Preskill qutrit (ququart) as a ternary (quaternary) quantum memory and achieved beyond break-even error correction with a gain of 1.82 ± 0.03 (1.87 ± 0.03). This work represents a novel way of leveraging the large Hilbert space of a harmonic oscillator to realize hardware-efficient quantum error correction.

『摘要』 希尔伯特空间维度是量子信息处理的关键资源。不仅大的整体希尔伯特空间是量子纠错的基本要求,而且大的局部希尔伯特空间也有助于更高效地实现量子门和算法。因此,近年来,为开发使用量子比特(d维量子系统,d > 2)作为量子信息基本单元的量子计算平台,人们进行了大量的实验努力。与量子比特一样,从长远来看,这些量子比特的量子纠错将是必要的,但迄今为止,逻辑量子比特的纠错尚未在实验中得到验证。在此,我们报告了使用Gottesman-Kitaev-Preskill玻色子码实验实现了纠错逻辑三态量子比特(d = 3)和四态量子比特(d = 4)。我们使用强化学习优化Gottesman-Kitaev-Preskill三态量子比特(四态量子比特)作为三进制(四进制)量子存储器,并实现了超过损益平衡点的纠错,增益为1.82±0.03(1.87±0.03)。这项工作代表了一种利用谐振子的大希尔伯特空间来实现硬件高效量子纠错的新方法。
『总结』 本研究通过使用Gottesman-Kitaev-Preskill玻色子码,实验实现了纠错逻辑三态量子比特和四态量子比特,并展示了利用谐振子大希尔伯特空间进行硬件高效量子纠错的新方法。
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『Abstract』The formation of accessible chromatin around DNA double-strand breaks is essential for their efficient repair . Although the linker histone H1 is known to facilitate higher-order chromatin compaction , the mechanisms by which H1 modifications regulate chromatin relaxation in response to DNA damage are unclear. Here we show that CTP synthase 1 (CTPS1)-catalysed deamidation of H1 asparagine residues 76 and 77 triggers the sequential acetylation of lysine 75 following DNA damage, and this dual modification of H1 is associated with chromatin opening. Mechanistically, the histone acetyltransferase p300 showed a preference for deamidated H1 as a substrate, establishing H1 deamidation as a prerequisite for subsequent acetylation. Moreover, high expression of CTPS1 was associated with resistance to cancer radiotherapy, in both mouse xenograft models and clinical cohorts. These findings provide new insights into how linker histones regulate dynamic chromatin alterations in the DNA damage response.

『摘要』 DNA双链断裂周围形成易接近的染色质对于其高效修复至关重要。尽管已知连接组蛋白H1可促进高级染色质压缩,但H1修饰调节DNA损伤后染色质松弛的机制尚不清楚。本研究发现,CTP合成酶1(CTPS1)催化H1第76和77位天冬酰胺残基的去酰胺化,可触发DNA损伤后第75位赖氨酸的连续乙酰化,H1的这种双重修饰与染色质开放相关。从机制上讲,组蛋白乙酰转移酶p300更倾向于将去酰胺化的H1作为底物,因此H1去酰胺化是后续乙酰化的先决条件。此外,在小鼠异种移植模型和临床队列中,CTPS1的高表达均与癌症放疗抗性相关。这些发现为连接组蛋白如何调节DNA损伤反应中的动态染色质改变提供了新的见解。
『总结』 本研究揭示了CTPS1催化H1去酰胺化和乙酰化的双重修饰机制,及其在染色质开放和癌症放疗抗性中的作用。
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『Abstract』Mitochondrial oxidative phosphorylation (OXPHOS) powers brain activity , and mitochondrial defects are linked to neurodegenerative and neuropsychiatric disorders . To understand the basis of brain activity and behaviour, there is a need to define the molecular energetic landscape of the brain . Here, to bridge the scale gap between cognitive neuroscience and cell biology, we developed a physical voxelization approach to partition a frozen human coronal hemisphere section into 703 voxels comparable to neuroimaging resolution (3 × 3 × 3 mm). In each cortical and subcortical brain voxel, we profiled mitochondrial phenotypes, including OXPHOS enzyme activities, mitochondrial DNA and volume density, and mitochondria-specific respiratory capacity. We show that the human brain contains diverse mitochondrial phenotypes driven by both topology and cell types. Compared with white matter, grey matter contains >50% more mitochondria. Moreover, the mitochondria in grey matter are biochemically optimized for energy transformation, particularly among recently evolved cortical brain regions. Scaling these data to the whole brain, we created a backwards linear regression model that integrates several neuroimaging modalities to generate a brain-wide map of mitochondrial distribution and specialization. This model predicted mitochondrial characteristics in an independent brain region of the same donor brain. This approach and the resulting MitoBrainMap of mitochondrial phenotypes provide a foundation for exploring the molecular energetic landscape that enables normal brain function. This resource also relates to neuroimaging data and defines the subcellular basis for regionalized brain processes relevant to neuropsychiatric and neurodegenerative disorders. All data are available at http://humanmitobrainmap.bcblab.com .

『摘要』 线粒体氧化磷酸化(OXPHOS)为大脑活动提供能量,线粒体缺陷与神经退行性疾病和精神神经障碍有关。为了理解大脑活动和行为的基础,有必要明确大脑的分子能量分布。本文为弥合认知神经科学与细胞生物学之间的规模差距,我们开发了一种物理体素化方法,将冷冻人脑冠状半球切面分割成703个体素,这些体素的分辨率(3×3×3毫米)可与神经影像学相媲美。在每个皮质和皮质下脑体素中,我们分析了线粒体表型,包括OXPHOS酶活性、线粒体DNA和体积密度以及线粒体特异性呼吸容量。研究表明,人类大脑中存在由拓扑结构和细胞类型共同驱动的多种线粒体表型。与白质相比,灰质中的线粒体数量多出50%以上。此外,灰质中的线粒体在生化方面进行了优化,以实现能量转换,特别是在近期进化的皮质脑区。我们将这些数据扩展到整个大脑,创建了一个后向线性回归模型,该模型整合了多种神经成像方式,以生成全脑线粒体分布和特化图。该模型预测了同一捐赠者大脑中独立脑区域的线粒体特征。这种方法和由此产生的线粒体表型MitoBrainMap为探索使大脑正常运作的分子能量分布奠定了基础。该资源还与神经影像学数据相关联,并定义了与神经精神障碍和神经退行性疾病相关的区域化脑过程的亚细胞基础。所有数据均可在http://humanmitobrainmap.bcblab.com上获取。
『总结』 本研究开发了一种物理体素化方法,绘制了人脑线粒体分布和特化图,为探索大脑分子能量分布以及与神经疾病相关的区域化脑过程提供了重要资源。
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『Abstract』Sensitive methods for detection of cell-free RNA (cfRNA) could facilitate non-invasive gene expression profiling and monitoring of diseases . Here we describe RARE-seq (random priming and affinity capture of cfRNA fragments for enrichment analysis by sequencing), a method optimized for cfRNA analysis. We demonstrate that platelet contamination can substantially confound cfRNA analyses and develop an approach to overcome it. In analytical validations, we find RARE-seq to be approximately 50-fold more sensitive for detecting tumour-derived cfRNA than whole-transcriptome RNA sequencing (RNA-seq), with a limit of detection of 0.05%. To explore clinical utility, we profiled 437 plasma samples from 369 individuals with cancer or non-malignant conditions and controls. Detection of non-small-cell lung cancer expression signatures in cfRNA increased with stage (6 out of 20 (30%) in stage I; 5 out of 8 (63%) in stage II; 10 out of 15 (67%) in stage III; 80 out of 96 (83% sensitivity) in stage IV at 95% specificity) and RARE-seq was more sensitive than tumour-naive circulating tumour DNA (ctDNA) analysis. In patients with EGFR -mutant non-small-cell lung cancer who developed resistance to tyrosine kinase inhibitors, we detected both histological transformation and mutation-based resistance mechanisms. Finally, we demonstrate the potential utility of RARE-seq for determination of tissue of origin, assessing benign pulmonary conditions and tracking response to mRNA vaccines. These results highlight the potential value of ultrasensitive cfRNA analysis and provide proof of concept for diverse clinical applications.

『摘要』 游离RNA(cell-free RNA,cfRNA)的灵敏检测方法有助于实现非侵入性基因表达谱分析和疾病监测。本研究团队描述了RARE-seq(通过随机引物和亲和捕获cfRNA片段进行测序富集分析),这是一种针对cfRNA分析优化的方法。研究团队证明,血小板污染会显著干扰cfRNA分析,并开发了一种方法来克服这一问题。在分析验证中,研究团队发现RARE-seq在检测肿瘤来源的cfRNA方面比全转录组RNA测序(RNA-seq)敏感约50倍,检测下限为0.05%。为探索其临床实用性,研究团队对来自369名癌症或非恶性疾病患者及对照个体的437份血浆样本进行了检测。cfRNA中非小细胞肺癌(NSCLC)表达特征的检出率随分期而增加(I期20例中6例(30%);II期8例中5例(63%);III期15例中10例(67%);IV期96例中80例(83%灵敏度),特异性为95%),并且RARE-seq比肿瘤初治循环肿瘤DNA(ctDNA)分析更灵敏。在对酪氨酸激酶抑制剂产生耐药性的EGFR突变非小细胞肺癌患者中,研究团队检测到了组织学转化和基于突变的耐药机制。最后,研究团队证明了RARE-seq在确定组织来源、评估良性肺部疾病和追踪mRNA疫苗反应方面的潜在用途。这些结果凸显了超灵敏cfRNA分析的价值,并为多种临床应用提供了概念验证。
『总结』 RARE-seq作为一种优化的cfRNA分析方法,在癌症检测和监测方面展现出高灵敏度和广泛应用前景。
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『Abstract』Acanthocephala (thorny-headed worms), characterized by the presence of an eversible proboscis with hooks, are a diverse endoparasitic group that infect a wide range of vertebrates and invertebrates . Although long regarded as a separate phylum, they have several putative sister taxa based on morphological features, including Platyhelminthes (flatworms) , Priapulida (penis worms) and Rotifera (wheel animals) . Molecular phylogenies have instead recovered them within rotifers , suggesting acanthocephalans are derived from free-living worms with a jaw apparatus (Gnathifera). Their only fossil record is Late Cretaceous eggs , contributing limited palaeontological information to deciphering their early evolution. Here we describe an acanthocephalan body fossil, Juracanthocephalus daohugouensis gen. et. sp. nov., from the Middle Jurassic Daohugou biota of China. Juracanthocephalus shows unambiguous acanthocephalan characteristics, for example a hooked proboscis, a bursa, as well as a jaw apparatus with discrete elements that is typical of other gnathiferans. Juracanthocephalus shares features with Seisonidea (an epizoic member of Rotifera) and Acanthocephala, bridging the evolutionary gap between jawed rotifers and the obligate parasitic, jawless acanthocephalans. Our results reveal previously unrecognized ecological and morphological diversity in ancient Acanthocephala and highlight the significance of transitional fossils, revealing the origins of this highly enigmatic group of living organisms.

『摘要』 棘头虫(棘头动物门生物),其特征是具有一个带有钩的可翻转吻部,是一类多样化的内寄生虫群体,可感染多种脊椎动物和无脊椎动物。尽管棘头虫长期被视为一个独立的门,但根据形态特征,它们与几个假定的姊妹分类群有关,包括扁形动物门(扁虫)、鳃曳动物门(阴茎虫)和轮虫动物门(轮形动物)。然而,分子系统发育研究却将它们归入轮虫动物门内,这表明棘头虫是由具有颚器的自由生活虫类(颚胃动物)演化而来的。目前棘头虫唯一的化石记录是白垩纪晚期的虫卵,这为解读其早期演化提供的古生物学信息极为有限。本文描述了采自中国中侏罗纪道虎沟生物群中的一种棘头虫躯体化石——道虎沟棘头虫(新属新种)。道虎沟棘头虫具有明确的棘头虫特征,例如带钩的吻部、囊体和具有离散元素的颚器,这些特征是其他颚胃动物的典型特征。道虎沟棘头虫兼具旋轮动物(轮虫动物门中的一种表栖成员)和棘头虫的特征,填补了颚器发达的轮虫和严格寄生、无颚器的棘头虫之间的演化空白。我们的研究结果揭示了古代棘头虫此前未知的生态和形态多样性,并强调了过渡化石的重要性,其揭示了这类极为神秘的现生物种的起源。
『总结』 本研究描述了一种来自中国中侏罗纪的新棘头虫化石,揭示了棘头虫早期演化的新信息,强调了过渡化石在理解此类生物起源中的重要性。
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『Abstract』High-capacity lithium-ion batteries (LIBs) play a critical role as power sources across diverse applications, including portable electronics, electric vehicles (EVs) and renewable-energy-storage systems . However, there is growing concern about the safety of integrated LIB systems, with reports of up to 9,486 incidents between 2020 and 2024 (ref. ). To ensure the safe application of commercial LIBs, it is essential to capture internal signals that enable early failure diagnosis and warning. Monitoring non-uniform temperature and strain distributions within the jelly-roll structures of the battery provides a promising approach to achieving this goal . Here we propose a miniaturized and low-power-consumption system capable of accurate sensing and wireless transmission of internal temperature and strain signals inside LIBs, with negligible influence on its performance. The acquisition of internal temperature signals and the area ratio between initial internal-short-circuited regions and battery electrodes enables quantitative analysis of thermal fusing and thermal runaway phenomena, leading to the evaluation of the intensity of battery thermal runaway and recognition of thermal abuse behaviours. This work provides a foundation for designing next-generation smart LIBs with safety warning and failure positioning capabilities.

『摘要』 大容量锂离子电池(LIBs)在便携式电子设备、电动汽车(EVs)和可再生能源储存系统等众多应用中作为电源发挥着关键作用。然而,人们对集成锂离子电池系统的安全性日益担忧,据报道,2020年至2024年间发生了多达9486起相关事件。为确保商用锂离子电池的安全应用,必须捕捉能够实现早期故障诊断和预警的内部信号。监测电池卷绕结构内部温度和应变分布的不均匀性为实现这一目标提供了一种有前景的方法。本研究提出了一种小型化、低功耗的系统,能够准确感知并无线传输锂离子电池内部的温度和应变信号,同时对电池性能的影响微乎其微。通过获取内部温度信号以及初始内部短路区域与电池电极之间的面积比,可以对热熔断和热失控现象进行定量分析,从而评估电池热失控的强度并识别热滥用行为。本研究为设计具有安全预警和故障定位能力的下一代智能锂离子电池奠定了基础。
『总结』 本研究开发了一种小型低功耗系统,能准确监测并无线传输锂离子电池内部温度和应变信号,有助于实现早期故障诊断,为设计更安全的智能电池提供了基础。
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『Abstract』Many natural motor skills, such as speaking or locomotion, are acquired through a process of trial-and-error learning over the course of development. It has long been hypothesized, motivated by observations in artificial learning experiments, that dopamine has a crucial role in this process. Dopamine in the basal ganglia is thought to guide reward-based trial-and-error learning by encoding reward prediction errors , decreasing after worse-than-predicted reward outcomes and increasing after better-than-predicted ones. Our previous work in adult zebra finches—in which we changed the perceived song quality with distorted auditory feedback—showed that dopamine in Area X, the singing-related basal ganglia, encodes performance prediction error: dopamine is suppressed after worse-than-predicted (distorted syllables) and activated after better-than-predicted (undistorted syllables) performance . However, it remains unknown whether the learning of natural behaviours, such as developmental vocal learning, occurs through dopamine-based reinforcement. Here we tracked song learning trajectories in juvenile zebra finches and used fibre photometry to monitor concurrent dopamine activity in Area X. We found that dopamine was activated after syllable renditions that were closer to the eventual adult version of the song, compared with recent renditions, and suppressed after renditions that were further away. Furthermore, the relationship between dopamine and song fluctuations revealed that dopamine predicted the future evolution of song, suggesting that dopamine drives behaviour. Finally, dopamine activity was explained by the contrast between the quality of the current rendition and the recent history of renditions—consistent with dopamine’s hypothesized role in encoding prediction errors in an actor–critic reinforcement-learning model . Reinforcement-learning algorithms have emerged as a powerful class of model to explain learning in reward-based laboratory tasks, as well as for driving autonomous learning in artificial intelligence . Our results suggest that complex natural behaviours in biological systems can also be acquired through dopamine-mediated reinforcement learning.

『摘要』 在发育过程中,许多自然运动技能,如说话或运动,都是通过试错学习的过程获得的的。受人工学习实验观察结果的启发,人们很早就假设多巴胺在这一过程中起着至关重要的作用。基底神经节中的多巴胺被认为通过编码奖励预测误差来指导基于奖励的试错学习,在奖励结果低于预测值时会减少,而在奖励结果高于预测值时会增加。我们之前在成年斑马雀身上的工作(通过扭曲的听觉反馈来改变它们感知到的歌声质量)表明,与歌唱相关的基底神经节X区的多巴胺会编码表现预测误差:在表现低于预测值(扭曲的音节)时受到抑制,而在表现高于预测值(未扭曲的音节)时被激活。然而,目前尚不清楚自然行为的学习,如发育期的声乐学习,是否也是通过基于多巴胺的强化来进行的。在这里,我们追踪了幼年斑马雀的歌曲学习轨迹,并使用光纤光度法监测X区同时发生的多巴胺活动。我们发现,与最近的演唱相比,当音节演唱更接近歌曲的最终成人版本时,多巴胺会被激活,而当音节演唱与最终版本相差更远时,多巴胺则会受到抑制。此外,多巴胺与歌曲波动之间的关系表明,多巴胺可以预测歌曲的未来演变,这表明多巴胺对行为有驱动作用。最后,多巴胺的活动可以通过当前演唱质量与最近演唱历史的质量之间的对比来解释,这与多巴胺在行动者-评论家强化学习模型中编码预测误差的假设作用相一致。强化学习算法已成为一类强大的模型,可用于解释基于奖励的实验室任务中的学习,以及驱动人工智能中的自主学习。我们的研究结果表明,生物系统中复杂的自然行为也可以通过多巴胺介导的强化学习获得。
『总结』 研究表明,生物系统中复杂的自然行为,如斑马雀的发育期声乐学习,可以通过多巴胺介导的强化学习过程获得。
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『Abstract』Debris disks are exoplanetary systems that contain planets, minor bodies (asteroids, Kuiper belt objects, comets and so on) and micrometre-sized debris dust . Because water ice is the most common frozen volatile, it plays an essential role in the formation of planets and minor bodies. Although water ice has been commonly found in Kuiper belt objects and comets in the Solar System , no definitive evidence for water ice in debris disks has been obtained to date . Here we report the discovery of water ice in the HD 181327 debris disk using the near-infrared spectrograph onboard the James Webb Space Telescope. We detected the solid-state broad absorption feature of water ice at 3 µm including a distinct Fresnel peak at 3.1 µm, which is indicative of large, crystalline water-ice particles. Gradients in the water-ice feature as a function of stellocentric distance reveal a dynamic environment in which water ice is destroyed and replenished. We estimated the water-ice mass fractions as ranging from 0.1% at approximately 85 au to 21% at approximately 113 au, indicating the presence of a water-ice reservoir in the HD 181327 disk beyond the snow line. The icy bodies that release water ice in HD 181327 are probably the extra-solar counterparts of water-ice-rich Kuiper belt objects in our Solar System.

『摘要』 碎片盘是包含行星、小天体(小行星、柯伊伯带天体、彗星等)以及微米级碎片尘埃的外行星系统。由于水冰是最常见的冰冻挥发物,它在行星和小天体的形成过程中起着至关重要的作用。尽管在太阳系中的柯伊伯带天体和彗星中已经普遍发现了水冰,但迄今为止尚未获得碎片盘中存在水冰的明确证据。在此,我们报告使用詹姆斯·韦伯太空望远镜上的近红外光谱仪在HD 181327碎片盘中发现了水冰。我们在3微米处检测到了水冰的固态宽吸收特征,包括在3.1微米处的一个明显的弗雷斯内尔峰,这表明存在大型结晶水冰颗粒。水冰特征随恒星中心距离变化的梯度揭示了一个水冰不断被破坏和补充的动态环境。我们估计,水冰的质量分数在约85天文单位处为0.1%,在约113天文单位处为21%,这表明在HD 181327盘的雪线之外存在一个水冰储存库。在HD 181327中释放水冰的冰冷天体可能是我们太阳系中富含水冰的柯伊伯带天体的外星对应物。
『总结』 研究团队使用詹姆斯·韦伯太空望远镜首次在HD 181327碎片盘中发现了水冰,并估计在该盘的雪线之外存在水冰储存库。
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『Abstract』Flowering plant sexual reproduction requires double fertilization, yielding embryo and endosperm seed compartments: the latter supports embryo growth and seed germination. In an experiment to generate haploid embryos through inhibition of pollen phospholipase activity in sunflower ( Helianthus annus ), we serendipitously discovered that emasculated sunflowers spontaneously form parthenogenic haploid seed. Exploration of genetic, chemical and environmental factors demonstrated that a specific genotype background enabled high parthenogenesis and that full spectrum high-intensity light supplementation boosted parthenogenesis, yielding hundreds of haploid seeds per head. Induction of doubled haploid plants can greatly accelerate plant breeding efficiency; however, despite successful engineering of haploid induction in many crops, few reported systems are commercially scalable . Here we report efficient methods of chemical emasculation and genome doubling to produce fertile plants and enable a scalable sunflower doubled haploid system.

『摘要』 开花植物的有性生殖需要双受精,形成胚和胚乳种子部分:后者支持胚的生长和种子的萌发。在一项通过抑制向日葵(Helianthus annus)花粉磷脂酶活性来产生单倍体胚的实验中,我们意外发现,去雄的向日葵可以自发形成孤雌生殖单倍体种子。对遗传、化学和环境因素的探索表明,特定的基因型背景能够实现高孤雌生殖率,而全光谱高强度的光照补充能够促进孤雌生殖,每株可产生数百粒单倍体种子。诱导双单倍体植株可以大大提高植物育种效率;然而,尽管许多作物的单倍体诱导技术已成功开发,但很少有报道的系统可实现商业化规模应用。在此,我们报告了一种有效的化学去雄和基因组加倍方法,以生产可育植株,并建立一个可扩展的向日葵双单倍体体系。
『总结』 研究发现特定基因型背景和高强度光照可促进向日葵孤雌生殖,同时提出了化学去雄和基因组加倍的高效方法,为建立可扩展的向日葵双单倍体体系提供了可能。
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『Abstract』Pyrazoles are heterocycles commonly found as key substructures in agrochemicals and medicinally active compounds alike . Despite their pervasiveness, established methods fall notably short in delivering complex pyrazoles selectively due to issues of differentiation during either assembly or N- functionalization . This is a direct consequence of a dominant synthetic strategy that attempts to control selectivity-determining bonds between poorly differentiated starting materials. To overcome this longstanding challenge, we here describe a prototypical example of an alternative conceptual approach, ‘strategic atom replacement’, in which we synthesize N- alkyl pyrazoles from isothiazoles. The net forward transformation is a ‘swap’ of the isothiazole sulfur atom with a nitrogen atom and its associated alkyl fragment to deliver the alkylated pyrazole . Linking the two azoles is an orphaned heterocycle class, 1,2,3-thiadiazine- S -oxides, whose synthetic potential has yet to be tapped . By proceeding through these unusual heterocycles, the typical selectivity and separation challenges associated with exclusively bond-based pyrazole preparations are circumvented, and even minimally differentiated peripheral substituents can be discriminated to afford isomerically pure products.

『摘要』 吡唑是杂环化合物,通常作为农药和药物活性化合物中的关键子结构而出现。尽管吡唑类化合物无处不在,但由于在组装或N-官能化过程中的差异化问题,现有方法在选择性合成复杂吡唑类化合物方面明显不足。这是由一种主要合成策略所导致的直接结果,该策略试图控制分化程度较低的起始材料之间的选择性决定键。为了克服这一长期存在的挑战,我们在此描述了一种替代性概念方法的典型示例,即“战略原子替换”,我们通过该方法从异噻唑合成N-烷基吡唑。正向净转化是异噻唑硫原子与氮原子及其相关烷基片段的“交换”,从而得到烷基化吡唑。连接这两种唑类的是一个尚未开发的杂环类别,即1,2,3-噻二嗪-S-氧化物,其合成潜力尚待发掘。通过这种不寻常的杂环进行合成,规避了仅基于键的吡唑制备过程中典型的选择性和分离挑战,甚至可以区分分化程度极低的外围取代基,从而得到异构体纯品。
『总结』 本研究提出“战略原子替换”的新方法,通过异噻唑合成N-烷基吡唑,克服了传统吡唑合成方法中的选择性和分离挑战。
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『Abstract』Adenosine triphosphate (ATP) is the principal energy currency of all living cells . Metabolically impaired obligate intracellular parasites, such as the human pathogens Chlamydia trachomatis and Rickettsia prowazekii , can acquire ATP from their host cells through a unique ATP/adenosine diphosphate (ADP) translocator, which mediates the import of ATP into and the export of ADP and phosphate out of the parasite cells, thus allowing the exploitation of the energy reserves of host cells (also known as energy parasitism). This type of ATP/ADP translocator also exists in the obligate intracellular endosymbionts of protists and the plastids of plants and algae and has been implicated to play an important role in endosymbiosis . The plastid/parasite type of ATP/ADP translocator is phylogenetically and functionally distinct from the mitochondrial ATP/ADP translocator, and its structure and transport mechanism are still unknown. Here we report the cryo-electron microscopy structures of two plastid/parasite types of ATP/ADP translocators in the apo and substrate-bound states. The ATP/ADP-binding pocket is located at the interface between the N and C domains of the translocator, and a conserved asparagine residue within the pocket is critical for substrate specificity. The translocator operates through a rocker-switch alternating access mechanism involving the relative rotation of the two domains as rigid bodies. Our results provide critical insights for understanding ATP translocation across membranes in energy parasitism and endosymbiosis and offer a structural basis for developing drugs against obligate intracellular parasites.

『摘要』 腺苷三磷酸(ATP)是所有活细胞的主要能量货币。代谢受损的专性细胞内寄生生物,如人类病原体沙眼衣原体和普氏立克次体,可通过一种独特的ATP/腺苷二磷酸(ADP)转运蛋白从宿主细胞中获取ATP,该转运蛋白介导ATP进入寄生细胞以及ADP和磷酸盐从寄生细胞中导出,从而利用宿主细胞的能量储备(也称为能量寄生)。这种ATP/ADP转运蛋白也存在于原生生物的专性细胞内共生体和植物及藻类的质体中,并在内共生中发挥着重要作用。质体/寄生型的ATP/ADP转运蛋白在进化起源和功能上与线粒体ATP/ADP转运蛋白不同,其结构和转运机制仍不清楚。在此,我们报告了两种质体/寄生型ATP/ADP转运蛋白在空载状态和底物结合状态下的冷冻电子显微镜结构。ATP/ADP结合口袋位于转运蛋白N端和C端结构域的界面处,口袋内一个保守的天冬酰胺残基对底物特异性至关重要。转运蛋白通过一种涉及两个结构域作为刚体相对旋转的摇摆开关交替访问机制进行运作。我们的研究结果为理解能量寄生和内共生中的ATP跨膜转运提供了关键见解,并为开发针对专性细胞内寄生虫的药物提供了结构基础。
『总结』 本研究揭示了质体/寄生型ATP/ADP转运蛋白的结构和机制,为理解能量寄生和内共生中的ATP跨膜转运提供了新见解,并为药物开发奠定了基础。
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『Abstract』Graphene and transition metal dichalcogenide flat-band systems show similar phase diagrams, replete with magnetic and superconducting phases. An abiding question has been whether magnetic ordering competes with superconductivity or facilitates pairing. For example, recent studies of Bernal bilayer graphene in the presence of enhanced spin–orbit coupling show a substantial increase in the observed domain and critical temperature T c of superconducting states ; however, the mechanism for this enhancement remains unknown. Here we show that introducing spin–orbit coupling in rhombohedral trilayer graphene (RTG) by substrate proximity effect generates new superconducting pockets for both electron and hole doping, with maximal T c ≈ 300 mK, which is three times larger than in RTG encapsulated by hexagonal boron nitride. Using local magnetometry, we show that superconductivity straddles a transition between a spin-canted state with a finite in-plane magnetic moment and a state with complete spin–valley locking. This transition is reproduced in our Hartree–Fock calculations, in which this transition is driven by the competition between spin–orbit coupling and the carrier-density-tuned Hund’s interaction. Our experiment suggests that the enhancement of superconductivity by spin–orbit coupling is driven by a quantitative change in the canting angle rather than a change in the ground state symmetry. These results align with a recently proposed mechanism for the enhancement of superconductivity , in which fluctuations in the spin-canting order contribute to the pairing interaction.

『摘要』 石墨烯和过渡金属二硫化物平带系统表现出相似的相图,其中充满了磁性和超导相。一个长期存在的问题是,磁有序是与超导竞争还是有利于超导配对。例如,最近对存在增强自旋-轨道耦合的Bernal双层石墨烯的研究表明,观察到的超导态畴和临界温度Tc显著增加;然而,这种增强的机制仍不清楚。本文中,我们发现通过衬底邻近效应在菱面体三层石墨烯(RTG)中引入自旋-轨道耦合,为电子和空穴掺杂都产生了新的超导区域,最高Tc约为300mK,这是被六方氮化硼封装的RTG的三倍。我们使用局部磁力测定法表明,超导性跨越了自旋倾斜态(具有有限面内磁矩)和自旋-谷完全锁定态之间的转变。这一转变在我们的Hartree-Fock计算中得到了复现,其中这种转变是由自旋-轨道耦合和载流子密度调制的Hund相互作用之间的竞争驱动的。我们的实验表明,自旋-轨道耦合对超导性的增强是由倾斜角的定量变化驱动的,而非由基态对称性的改变驱动。这些结果与最近提出的一种超导性增强机制相吻合,即自旋倾斜序的波动有助于配对相互作用。
『总结』 研究发现,自旋-轨道耦合通过在菱面体三层石墨烯中引入新超导区域增强了超导性,且这种增强与自旋倾斜角的定量变化有关。
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『Abstract』Methane is an important greenhouse gas and its atmospheric concentration has almost tripled since pre-industrial times . Atmospheric methane mixing ratios vary seasonally, with the seasonal cycle amplitude (SCA) having decreased in northern high latitudes and increased in the subtropics and tropics since the 1980s . These opposing SCA trends can help understanding of long-term changes in the global methane budget, as methane emissions and sinks have opposing effects on the SCA . However, trends in the methane SCA have not yet been explored in detail . Here we use a suite of atmospheric transport model simulations and attribute the observed trends in the seasonal amplitude of methane to changes in emissions and the atmospheric sink from reaction with the hydroxyl radical (OH). We find that the decreasing amplitude in the northern high latitudes is mainly caused by an increase in natural emissions (such as wetlands) owing to a warmer climate, adding evidence to previous studies suggesting a positive climate feedback . In contrast, the enhanced methane amplitude in the subtropics and tropics is mainly attributed to strengthened OH oxidation. Our results provide independent evidence for an increase in tropospheric OH concentration of 10 ± 1% since 1984, which together with an increasing atmospheric methane concentration suggests a 21 ± 1% increase in the atmospheric methane sink.

『摘要』 甲烷是一种重要的温室气体,自工业化前时代以来,其大气浓度几乎增加了两倍。大气中甲烷的混合比例随季节变化,自20世纪80年代以来,季节周期振幅(SCA)在高纬度北方地区有所降低,而在亚热带和热带地区则有所增加。这些相反的季节周期振幅趋势有助于理解全球甲烷收支的长期变化,因为甲烷排放和汇对季节周期振幅有相反的影响。然而,甲烷季节周期振幅的趋势尚未得到详细研究。在本研究中,我们使用了一系列大气传输模型模拟,将观察到的甲烷季节振幅趋势归因于排放量的变化和与羟基(OH)反应的大气汇的变化。我们发现,高纬度北方地区振幅的降低主要是由气候变暖导致的自然排放量(如湿地排放)增加所致,这为先前表明存在正气候反馈的研究提供了佐证。相比之下,亚热带和热带地区甲烷振幅的增强则主要归因于OH氧化的增强。我们的研究结果为自1984年以来对流层OH浓度增加10±1%提供了独立证据,这一发现结合不断上升的大气甲烷浓度,表明大气甲烷汇增加了21±1%。
『总结』 研究发现甲烷季节周期振幅在高纬度降低、在低纬度和热带增强,这分别与气候变暖导致的自然排放增加和OH氧化增强有关,为大气甲烷汇的增加提供了证据。
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『Abstract』Plant absorption is important for the entry of many pollutants into food chains. Although terrestrial microplastics (MPs) can be absorbed by the roots , their upward translocation is slow . Meanwhile, atmospheric MPs are widely present , but strong evidence on their direct absorption by plants is still lacking. Here, analyses using mass spectrometry detection show the widespread occurrence of polyethylene terephthalate (PET) and polystyrene (PS) polymers and oligomers in plant leaves, and identify that their levels increase with atmospheric concentrations and the leaf growth duration. The concentrations of PET and PS polymers can reach up to 10 ng per g dry weight in leaves at the high-pollution areas studied, such as the Dacron factory and a landfill site, and 10 –10 ng per g dry weight of PET and PS can be detected in the open-air-grown leafy vegetables. Nano-sized PET and PS particles in the leaves were visually detected by hyperspectral imaging and atomic force microscopy–infrared spectroscopy. Absorption of the proactively exposed non-labelled, fluorescently labelled or europium-labelled plastic particles by maize ( Zea mays L.) leaves through stomatal pathways, as well as their translocation to the vascular tissue through the apoplastic pathway, and accumulation in trichomes was identified using hyperspectral imaging, confocal microscopy and laser-ablation inductively coupled plasma mass spectrometry. Our results demonstrate that the absorption and accumulation of atmospheric MPs by plant leaves occur widely in the environment, and this should not be neglected when assessing the exposure of humans and other organisms to environmental MPs.

『摘要』 许多污染物通过植物吸收进入食物链,这一过程至关重要。尽管陆生微塑料(MPs)可以被植物根部吸收,但其向上转运的速度很慢。同时,大气中的微塑料也普遍存在,但目前仍缺乏它们被植物直接吸收的有力证据。本研究通过质谱检测分析发现,植物叶片中广泛存在聚对苯二甲酸乙二醇酯(PET)和聚苯乙烯(PS)聚合物及低聚物,且其含量随着大气浓度和叶片生长时间的增加而增加。在研究的高污染地区,如涤纶厂和垃圾填埋场,叶片中PET和PS聚合物的浓度最高可达每克干重10纳克;而在露天种植的叶菜中,也可检测到每克干重10–10纳克的PET和PS。通过高光谱成像和原子力显微镜-红外光谱,在叶片中直观检测到了纳米级的PET和PS颗粒。利用高光谱成像、共聚焦显微镜和激光剥蚀电感耦合等离子体质谱,观察到未标记、荧光标记或铕标记的塑料颗粒均可通过气孔途径被玉米(Zea mays L.)叶片主动吸收,并通过质外体途径转运至维管组织,最终在毛状体中积累。研究结果表明,植物叶片对大气中微塑料的吸收和积累在环境中普遍存在,在评估人类和其他生物接触环境微塑料的风险时,这一点不容忽视。
『总结』 研究发现植物叶片能广泛吸收并积累大气中的微塑料,这在对人类和其他生物的环境微塑料暴露评估中不容忽视。
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『Abstract』Navigating social environments is a fundamental challenge for the brain. It has been established that the brain solves this problem, in part, by representing social information in an agent-centric manner; knowledge about others’ abilities or attitudes is tagged to individuals such as ‘oneself’ or the ‘other’ . This intuitive approach has informed the understanding of key nodes in the social parts of the brain, the dorsomedial prefrontal cortex (dmPFC) and the anterior cingulate cortex (ACC) . However, the patterns or combinations in which individuals might interact with one another is as important as the identities of the individuals. Here, in four studies using functional magnetic resonance imaging, behavioural experiments and a social group decision-making task, we show that the dmPFC and ACC represent the combinatorial possibilities for social interaction afforded by a given situation, and that they do so in a compressed format resembling the basis functions used in spatial, visual and motor domains . The basis functions align with social interaction types, as opposed to individual identities. Our results indicate that there are deep analogies between abstract neural coding schemes in the visual and motor domain and the construction of our sense of social identity.

『摘要』 在社交环境中进行导航是大脑面临的一项基本挑战。已有研究表明,大脑部分地通过以主体为中心的方式表征社交信息来解决这一问题;关于他人能力或态度的知识会被标记为“自己”或“他人”等个体。这种直观的方法有助于理解大脑社交部分的关键节点,即背内侧前额叶皮层(dmPFC)和前扣带皮层(ACC)。然而,个体之间可能产生的互动模式或组合与个体的身份同样重要。在本研究中,我们通过四项研究,使用功能磁共振成像、行为实验和社交群体决策任务,发现dmPFC和ACC表征了特定情境下社交互动的组合可能性,并且它们以一种类似于空间、视觉和运动领域中使用的基函数的压缩格式来实现这一点。这些基函数与社交互动类型相一致,而非个体身份。我们的研究结果表明,视觉和运动领域中的抽象神经编码方案与我们的社会身份感的构建之间存在深刻的相似性。
『总结』 研究发现背内侧前额叶皮层和前扣带皮层以压缩格式表征社交互动的组合可能性,类似于视觉和运动领域中的基函数,表明神经编码方案与社会身份构建有深刻相似性。
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『Abstract』Microglia are the resident immune cells in the brain and have pivotal roles in neurodevelopment and neuroinflammation . This study investigates the function of the immune-checkpoint molecule TIM-3 (encoded by HAVCR2 ) in microglia. TIM-3 was recently identified as a genetic risk factor for late-onset Alzheimer’s disease , and it can induce T cell exhaustion . However, its specific function in brain microglia remains unclear. We demonstrate in mouse models that TGFβ signalling induces TIM-3 expression in microglia. In turn, TIM-3 interacts with SMAD2 and TGFBR2 through its carboxy-terminal tail, which enhances TGFβ signalling by promoting TGFBR-mediated SMAD2 phosphorylation, and this process maintains microglial homeostasis. Genetic deletion of Havcr2 in microglia leads to increased phagocytic activity and a gene-expression profile consistent with the neurodegenerative microglial phenotype (MGnD), also referred to as disease-associated microglia (DAM). Furthermore, microglia-targeted deletion of Havcr2 ameliorates cognitive impairment and reduces amyloid-β pathology in 5×FAD mice (a transgenic model of Alzheimer’s disease). Single-nucleus RNA sequencing revealed a subpopulation of MGnD microglia in Havcr2 -deficient 5×FAD mice characterized by increased pro-phagocytic and anti-inflammatory gene expression alongside reduced pro-inflammatory gene expression. These transcriptomic changes were corroborated by single-cell RNA sequencing data across most microglial clusters in Havcr2 -deficient 5×FAD mice. Our findings reveal that TIM-3 mediates microglia homeostasis through TGFβ signalling and highlight the therapeutic potential of targeting microglial TIM-3 in Alzheimer’s disease.

『摘要』 小胶质细胞是脑中的常驻免疫细胞,在神经发育和神经炎症中发挥着关键作用。本研究探讨了免疫检查点分子TIM-3(由HAVCR2编码)在小胶质细胞中的功能。TIM-3最近被确定为晚发性阿尔茨海默病的遗传风险因素,可诱导T细胞耗竭。然而,其在脑小胶质细胞中的具体功能尚不清楚。我们在小鼠模型中证明,TGFβ信号可诱导小胶质细胞中TIM-3的表达。反过来,TIM-3通过其羧基末端尾部与SMAD2和TGFBR2相互作用,通过促进TGFBR介导的SMAD2磷酸化来增强TGFβ信号,这一过程维持了小胶质细胞的稳态。小胶质细胞中Havcr2的基因缺失会导致吞噬活性增加,并表现出与神经退行性小胶质细胞表型(MGnD)(也称为疾病相关小胶质细胞(DAM))一致的基因表达谱。此外,靶向小胶质细胞删除Havcr2可改善5×FAD小鼠(阿尔茨海默病转基因模型)的认知障碍,并减轻β淀粉样蛋白病变。单细胞核RNA测序发现,Havcr2缺陷的5×FAD小鼠中存在一个MGnD小胶质细胞亚群,其特征是促吞噬和抗炎基因表达增加,而促炎基因表达减少。通过对Havcr2缺陷的5×FAD小鼠中大多数小胶质细胞簇进行单细胞RNA测序分析,进一步证实了这些转录组变化。我们的研究结果表明,TIM-3通过TGFβ信号介导小胶质细胞稳态,并强调了靶向小胶质细胞TIM-3在阿尔茨海默病中的治疗潜力。
『总结』 研究发现TIM-3通过TGFβ信号维持小胶质细胞稳态,靶向小胶质细胞TIM-3或成阿尔茨海默病治疗新策略。
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『Abstract』Ionotropic glutamate receptors (iGluRs) are tetrameric ligand-gated ion channels that mediate most excitatory neurotransmission . iGluRs are gated by glutamate, where on glutamate binding, they open their ion channels to enable cation influx into postsynaptic neurons, initiating signal transduction . The structural mechanics of how glutamate gating occurs in full-length iGluRs is not well understood. Here, using the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid subtype iGluR (AMPAR), we identify the glutamate-gating mechanism. AMPAR activation by glutamate is augmented at physiological temperatures. By preparing AMPARs for cryogenic-electron microscopy at these temperatures, we captured the glutamate-gating mechanism. Activation by glutamate initiates ion channel opening that involves all ion channel helices hinging away from the pore axis in a motif that is conserved across all iGluRs. Desensitization occurs when the local dimer pairs decouple and enables closure of the ion channel below through restoring the channel hinges and refolding the channel gate. Our findings define how glutamate gates iGluRs, provide foundations for therapeutic design and demonstrate how physiological temperatures can alter iGluR function.

『摘要』 离子型谷氨酸受体(iGluRs)是四聚体配体门控离子通道,介导大多数兴奋性神经传递。iGluRs由谷氨酸门控,谷氨酸与其结合后,离子通道打开,使阳离子流入突触后神经元,从而启动信号转导。目前对于全长iGluRs中谷氨酸门控的结构机制尚不完全清楚。本研究利用α-氨基-3-羟基-5-甲基-4-异噁唑丙酸亚型iGluR(AMPAR),揭示了谷氨酸门控机制。在生理温度下,谷氨酸对AMPAR的激活作用增强。我们在这些温度下制备AMPAR,用于冷冻电子显微镜成像,从而捕捉到了谷氨酸门控机制。谷氨酸激活会启动离子通道开放,这一过程中,所有离子通道螺旋都远离孔轴转动,这一基序在所有iGluRs中都是保守的。当局部二聚体对解耦时,会发生脱敏,并通过恢复通道铰链和重构通道闸门,使下方的离子通道得以关闭。我们的研究结果阐明了谷氨酸如何门控iGluRs,为治疗设计提供了基础,并展示了生理温度如何改变iGluR功能。
『总结』 本研究揭示了离子型谷氨酸受体(iGluRs)的谷氨酸门控机制,为相关疾病的治疗设计提供了理论基础,并发现生理温度能影响iGluR功能。
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『Abstract』Haematopoietic stem cells maintain blood production throughout life . Although extensively characterized using the laboratory mouse, little is known about clonal selection and population dynamics of the haematopoietic stem cell pool during murine ageing. We isolated stem cells and progenitors from young and old mice, identifying 221,890 somatic mutations genome-wide in 1,845 single-cell-derived colonies. Mouse stem cells and progenitors accrue approximately 45 somatic mutations per year, a rate only approximately threefold greater than human progenitors despite the vastly different organismal sizes and lifespans. Phylogenetic patterns show that stem and multipotent progenitor cell pools are established during embryogenesis, after which they independently self-renew in parallel over life, evenly contributing to differentiated progenitors and peripheral blood. The stem cell pool grows steadily over the mouse lifespan to about 70,000 cells, self-renewing about every 6 weeks. Aged mice did not display the profound loss of clonal diversity characteristic of human haematopoietic ageing. However, targeted sequencing showed small, expanded clones in the context of murine ageing, which were larger and more numerous following haematological perturbations, exhibiting a selection landscape similar to humans. Our data illustrate both conserved features of population dynamics of blood and distinct patterns of age-associated somatic evolution in the short-lived mouse.

『摘要』 造血干细胞在一生中维持着血液的产生。尽管利用实验小鼠进行了广泛的研究,但对小鼠衰老过程中造血干细胞池的克隆选择和群体动态仍知之甚少。我们从年轻和年老的小鼠中分离出干细胞和祖细胞,在1845个单细胞衍生菌落中发现了全基因组范围内的221890个体细胞突变。小鼠干细胞和祖细胞每年累积约45个体细胞突变,这一速率仅比人类祖细胞高大约三倍,尽管两者的有机体大小和寿命存在巨大差异。系统发育模式表明,干细胞和多能祖细胞池是在胚胎发育过程中建立的,之后它们在一生中平行地进行独立自我更新,均等地分化为祖细胞和外周血。小鼠的干细胞池在其生命周期中稳步增长至约70000个细胞,每6周左右自我更新一次。老年小鼠并未表现出人类造血衰老所特有的克隆多样性显著丧失的特征。然而,靶向测序显示,在小鼠衰老过程中会出现小而扩增的克隆,这些克隆在血液学扰动后变得更大、数量更多,表现出与人类相似的选择格局。我们的数据揭示了血液群体动态的保守特征以及短寿小鼠中与年龄相关的体细胞进化的独特模式。
『总结』 研究揭示了小鼠造血干细胞池的克隆选择和群体动态特征,以及小鼠衰老过程中的体细胞突变和克隆演化模式。
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『Abstract』Although learning in response to extrinsic reinforcement is theorized to be driven by dopamine signals that encode the difference between expected and experienced rewards , skills that enable verbal or musical expression can be learned without extrinsic reinforcement. Instead, spontaneous execution of these skills is thought to be intrinsically reinforcing . Whether dopamine signals similarly guide learning of these intrinsically reinforced behaviours is unknown. In juvenile zebra finches learning from an adult tutor, dopamine signalling in a song-specialized basal ganglia region is required for successful song copying, a spontaneous, intrinsically reinforced process . Here we show that dopamine dynamics in the song basal ganglia faithfully track the learned quality of juvenile song performance on a rendition-by-rendition basis. Furthermore, dopamine release in the basal ganglia is driven not only by inputs from midbrain dopamine neurons classically associated with reinforcement learning but also by song premotor inputs, which act by means of local cholinergic signalling to elevate dopamine during singing. Although both cholinergic and dopaminergic signalling are necessary for juvenile song learning, only dopamine tracks the learned quality of song performance. Therefore, dopamine dynamics in the basal ganglia encode performance quality during self-directed, long-term learning of natural behaviours.

『摘要』 尽管根据理论,由外在奖励驱动的学习是由多巴胺信号控制的,这些信号编码了预期奖励与实际获得奖励之间的差异,但无需外在奖励也能学会语言表达或音乐表达等技能。相反,人们认为这些技能的自发表现本身就是一种内在奖励。尚不清楚多巴胺信号是否同样引导这些内在奖励行为的学习。幼年斑马雀在学习成年导师的歌声时,需要歌曲特异性基底神经节区域的多巴胺信号才能成功模仿歌曲,这是一个自发且内在奖励的过程。本研究表明,基底神经节中的多巴胺动态变化与幼鸟每次歌曲表演的学习质量密切相关。此外,基底神经节中多巴胺的释放不仅受到传统上与强化学习相关的中脑多巴胺神经元的输入驱动,还受到歌曲运动前输入的驱动,后者通过局部胆碱能信号在唱歌时提高多巴胺水平。虽然胆碱能信号和多巴胺信号对幼年斑马雀学习歌声都是必要的,但只有多巴胺与歌声表演的学习质量相关。因此,在自我指导的长期自然行为学习过程中,基底神经节中的多巴胺动态变化编码了表演的质量。
『总结』 研究表明,基底神经节中的多巴胺信号不仅参与由外在奖励驱动的学习,还编码了幼年斑马雀在自发、内在奖励的歌声学习过程中的表演质量。
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『Abstract』RNA-binding proteins (RBPs) control varied processes, including RNA splicing, stability, transport and translation . Dysfunctional RNA–RBP interactions contribute to the pathogenesis of human disease ; however, characterizing the nature and dynamics of multiprotein assemblies on RNA has been challenging. Here, to address this, non-isotopic ligation-based ultraviolet-light-induced cross-linking and immunoprecipitation was combined with mass spectrometry (irCLIP-RNP) to identify RNA-dependent associated proteins (RDAPs) co-bound to RNA with any RBP of interest. irCLIP-RNP defined landscapes of multimeric protein assemblies on RNA, revealing patterns of RBP–RNA associations, including cell-type-selective combinatorial relationships between RDAPs and primary RBPs. irCLIP-RNP also defined dynamic RDAP remodelling in response to epidermal growth factor (EGF), revealing that EGF-induced recruitment of UPF1 adjacent to HNRNPC promotes splicing surveillance of cell proliferation mRNAs. To identify the RNAs simultaneously co-bound by multiple studied RBPs, a sequential immunoprecipitation irCLIP (Re-CLIP) method was also developed. Re-CLIP confirmed binding relationships observed in irCLIP-RNP and identified HNRNPC and UPF1 RBP co-binding on RND3 and DDX3X mRNAs. irCLIP-RNP and Re-CLIP provide a framework to identify and characterize dynamic RNA–protein assemblies in living cells.

『摘要』 RNA结合蛋白(RBP)控制包括RNA剪接、稳定性、转运和翻译在内的多种过程。RNA与RBP之间的相互作用发生障碍可促进人类疾病的发生;然而,表征RNA上多蛋白复合体的性质和动态一直是一项挑战。本研究为解决这一问题,将非同位素标记的基于连接反应的紫外诱导交联和免疫沉淀技术与质谱分析相结合(irCLIP-RNP),鉴定与任何感兴趣的RBP共同结合RNA的RNA依赖相关蛋白(RDAP)。irCLIP-RNP描绘了RNA上多聚体蛋白复合体的分布情况,揭示了RBP与RNA的结合模式,包括RDAP与主要RBP之间具有细胞类型选择性的组合关系。irCLIP-RNP还揭示了表皮生长因子(EGF)诱导的RDAP动态重塑过程,发现EGF诱导UPF1在HNRNPC附近募集,从而促进细胞增殖mRNA的剪接监控。为鉴定同时与多种所研究RBP结合的RNA,本研究还开发了一种序贯免疫沉淀irCLIP(Re-CLIP)方法。Re-CLIP验证了irCLIP-RNP中观察到的结合关系,并鉴定出HNRNPC和UPF1 RBP在RND3和DDX3X mRNA上的共同结合。irCLIP-RNP和Re-CLIP为研究活细胞中动态RNA-蛋白质复合体的鉴定和表征提供了一个框架。
『总结』 irCLIP-RNP和Re-CLIP技术能够揭示RNA上多蛋白复合体的动态变化和相互作用模式,为研究活细胞中RNA-蛋白质复合体的性质和功能提供了新的工具。
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『Abstract』When two massive objects (black holes, neutron stars or stars) in our universe fly past each other, their gravitational interactions deflect their trajectories . The gravitational waves emitted in the related bound-orbit system—the binary inspiral—are now routinely detected by gravitational-wave observatories . Theoretical physics needs to provide high-precision templates to make use of unprecedented sensitivity and precision of the data from upcoming gravitational-wave observatories . Motivated by this challenge, several analytical and numerical techniques have been developed to approximately solve this gravitational two-body problem. Although numerical relativity is accurate , it is too time-consuming to rapidly produce large numbers of gravitational-wave templates. For this, approximate analytical results are also required . Here we report on a new, highest-precision analytical result for the scattering angle, radiated energy and recoil of a black hole or neutron star scattering encounter at the fifth order in Newton’s gravitational coupling G , assuming a hierarchy in the two masses. This is achieved by modifying state-of-the-art techniques for the scattering of elementary particles in colliders to this classical physics problem in our universe. Our results show that mathematical functions related to Calabi–Yau (CY) manifolds, 2 n -dimensional generalizations of tori, appear in the solution to the radiated energy in these scatterings. We anticipate that our analytical results will allow the development of a new generation of gravitational-wave models, for which the transition to the bound-state problem through analytic continuation and strong-field resummation will need to be performed.

『摘要』 当宇宙中的两个大质量天体(黑洞、中子星或恒星)相互掠过时,它们的引力相互作用会使其轨迹发生偏转。相关束缚轨道系统——即双星旋近——所产生的引力波目前已被引力波天文台常规检测到。理论物理学需要提供高精度的模板,以利用未来引力波天文台提供的前所未有的灵敏度和精确度的数据。面对这一挑战,人们开发了几种分析和数值技术来近似求解这一引力二体问题。尽管数值相对论具有准确性,但要快速生成大量的引力波模板,所需时间太长。因此,也需要近似的分析结果。本文报告了在新牛顿引力耦合G的五阶下,黑洞或中子星散射碰撞的散射角、辐射能量和反冲的最新、最高精度的分析结果,并假设了两个质量之间存在层级关系。这是通过将用于对撞机中基本粒子散射的最先进技术改良后应用于宇宙中的这一经典物理问题而实现的。研究结果表明,在这些散射的辐射能量解中出现了与卡拉比-丘(Calabi-Yau,CY)流形——环面的2n维推广——有关的数学函数。我们预期,这些分析结果将促进新一代引力波模型的开发,并需要通过解析延拓和强场重求和将其过渡到束缚态问题。
『总结』 本文报告了在牛顿引力耦合五阶下,黑洞或中子星散射的高精度分析结果,并指出辐射能量的解中出现了与卡拉比-丘流形有关的数学函数,这将促进新一代引力波模型的开发。
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『Abstract』The relative twist angle between layers of near-lattice-matched van der Waals materials is critical for the emergent phenomena associated with moire flat bands . However, the concept of angle rotation control is not exclusive to moire superlattices in which electrons directly experience a twist-angle-dependent periodic potential. Instead, it can also be used to induce programmable symmetry-breaking perturbations with the goal of stabilizing desired correlated states. Here we experimentally demonstrate ‘moireless’ twist-tuning of superconductivity together with other correlated orders in Bernal bilayer graphene proximitized by tungsten diselenide. The precise alignment between the two materials systematically controls the strength of induced Ising spin–orbit coupling (SOC), profoundly altering the phase diagram. As Ising SOC is increased, superconductivity onsets at a higher displacement field and features a higher critical temperature, reaching up to 0.5 K. Within the main superconducting dome and in the strong Ising SOC limit, we find an unusual phase transition characterized by a nematic redistribution of holes among trigonally warped Fermi pockets and enhanced resilience to in-plane magnetic fields. The superconducting behaviour is theoretically compatible with the prominent role of interband interactions between symmetry-breaking Fermi pockets. Moreover, we identify two additional superconducting regions, one of which descends from an inter-valley coherent normal state and shows a Pauli-limit violation ratio exceeding 40, among the highest for all known superconductors . Our results provide insights into ultraclean graphene superconductors and underscore the potential of utilizing moireless-twist engineering across a wide range of van der Waals heterostructures.

『摘要』 近晶格匹配的范德华材料层之间的相对扭转角对于与摩尔平坦带相关的涌现现象至关重要。然而,角度旋转控制的概念并不局限于摩尔超晶格,在摩尔超晶格中,电子直接经历依赖于扭转角的周期性势场。相反,它还可用于诱导可编程的对称性破缺扰动,以稳定所需的关联态。在此,通过实验演示了在二硒化钨邻近作用下的Bernal双层石墨烯中超导性以及其他关联序的“无摩尔”扭转调控。两种材料之间的精确对准系统地控制了诱导的伊辛自旋-轨道耦合(SOC)的强度,从而深刻改变了相图。随着伊辛SOC的增加,超导性在更高的位移场下出现,并且具有更高的临界温度,最高可达0.5K。在主超导穹顶内和强伊辛SOC极限下,研究发现了一个不寻常的相变,其特征是空穴在三角扭曲的费米口袋中呈向列相重新分布,并且对面内磁场的抗性增强。从理论上讲,超导行为与对称性破缺费米口袋之间的带间相互作用的显著作用相符。此外,还发现了两个额外的超导区域,其中一个源自谷间相干的正常态,并显示出超过40的泡利极限违反比,这是所有已知超导体中最高的比例之一。研究结果为超净石墨烯超导体提供了见解,并强调了在整个范德华异质结构范围内利用无摩尔扭转工程的潜力。
『总结』 研究通过“无摩尔”扭转调控,在二硒化钨邻近作用下的Bernal双层石墨烯中实现了超导性调控,并发现了不寻常的相变和超导区域,强调了无摩尔扭转工程在范德华异质结构中的应用潜力。
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『Abstract』In the future, monsoon rainfall over densely populated South Asia is expected to increase, even as monsoon circulation weakens . By contrast, past warm intervals were marked by both increased rainfall and a strengthening of monsoon circulation , posing a challenge to understanding the response of the South Asian summer monsoon to warming. Here we show consistent South Asian summer monsoon changes in the mid-Pliocene, Last Interglacial, mid-Holocene and future scenarios, characterized by an overall increase in monsoon rainfall, a weakening of the monsoon trough-like circulation over the Bay of Bengal and a strengthening of the monsoon circulation over the northern Arabian Sea, as revealed by a compilation of proxy records and climate simulations. Increased monsoon rainfall is thermodynamically dominated by atmospheric moisture following the rich-get-richer paradigm, and dynamically dominated by the monsoon circulation driven by the enhanced land warming in subtropical western Eurasia and northern Africa. The coherent response of monsoon dynamics across warm climates reconciles past strengthening with future weakening, reinforcing confidence in future projections. Further prediction of South Asian summer monsoon circulation and rainfall by physics-based regression models using past information agrees well with climate model projections, with spatial correlation coefficients of approximately 0.8 and 0.7 under the high-emissions scenario. These findings underscore the promising potential of past analogues, bolstered by palaeoclimate reconstruction, in improving future South Asian summer monsoon projections.

『摘要』 未来,即使季风环流减弱,人口稠密的南亚地区的季风降雨预计也会增加。相比之下,过去的气温升高期间,降雨量增加,季风环流也加强,这给理解南亚夏季风对变暖的响应带来了挑战。本研究通过整合代用记录和气候模拟结果,揭示了中新世中期、末次间冰期、全新世中期以及未来情景下南亚夏季风的一致变化特征:季风降雨总体增加,孟加拉湾上空的季风槽状环流减弱,而阿拉伯海北部的季风环流加强。季风降雨量的增加在热力学上主要受大气水分“富者愈富”范式的控制,在动力学上则主要受亚热带西欧亚和非洲北部陆地变暖加剧所驱动的季风环流的影响。季风动力学在不同温暖气候下的一致响应协调了过去加强与未来减弱的现象,增强了对未来预测的信心。基于物理的回归模型利用过去的信息对南亚夏季风环流和降雨进行进一步预测,结果与气候模型预测高度一致,在高排放情景下,空间相关系数分别为0.8和0.7左右。这些发现凸显了古气候重建所强化的过去类似情况在改进未来南亚夏季风预测方面的潜力。
『总结』 南亚未来季风降雨将增加,尽管季风环流会减弱,这一发现与过去气候变暖期间的特征不同,但基于代用记录和气候模拟的研究增强了对未来预测的信心。
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『Abstract』Defence from environmental threats is provided by physical barriers that confer mechanical protection and prevent the entry of microorganisms . If microorganisms overcome those barriers, however, innate immune cells use toxic chemicals to kill the invading cells . Here we examine immune diversity across tissues and identify a population of neutrophils in the skin that expresses a broad repertoire of proteins and enzymes needed to build the extracellular matrix. In the naive skin, these matrix-producing neutrophils contribute to the composition and structure of the extracellular matrix, reinforce its mechanical properties and promote barrier function. After injury, these neutrophils build ‘rings’ of matrix around wounds, which shield against foreign molecules and bacteria. This structural program relies on TGFβ signalling; disabling the TGFβ receptor in neutrophils impaired ring formation around wounds and facilitated bacterial invasion. We infer that the innate immune system has evolved diverse strategies for defence, including one that physically shields the host from the outside world.

『摘要』 物理屏障可提供机械保护并阻止微生物进入,从而抵御环境威胁。然而,如果微生物突破了这些屏障,先天免疫细胞就会使用有毒化学物质来杀死入侵细胞。本研究检查了不同组织中的免疫多样性,并在皮肤中发现了一群中性粒细胞,这些细胞可表达构建细胞外基质所需的各种蛋白质和酶。在正常皮肤中,这些产生基质的中性粒细胞有助于细胞外基质的构成和结构形成,增强其机械性能,并促进屏障功能。受伤后,这些中性粒细胞会在伤口周围构建基质“环”,以抵御外来分子和细菌的入侵。这一结构程序依赖于转化生长因子β(transforming growth factor-β,TGFβ)信号传导;当中性粒细胞中的TGFβ受体失活时,会损害伤口周围的环形成,并促进细菌入侵。据此,我们推断出先天免疫系统已经进化出多种防御策略,其中一种就是通过物理屏障将宿主与外界隔离。
『总结』 研究发现皮肤中的一类中性粒细胞可构建细胞外基质,增强皮肤屏障并抵御细菌,揭示了先天免疫系统的一种物理防御策略。
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『Abstract』Several hydrogen-rich superconductors have been found to show unprecedentedly high critical temperatures , stimulating investigations into the nature of the superconductivity in these materials. Although their macroscopic superconducting properties are established , microscopic insights into the pairing mechanism remains unclear. Here we characterize the superconducting gap structure in the high-temperature superconductor H 3 S and its deuterium counterpart D 3 S by performing tunnelling spectroscopy measurements. The tunnelling spectra reveal that H 3 S and D 3 S both have a fully gapped structure, which could be well described by a single s -wave Dynes model, with gap values 2 Δ of approximately 60 meV and 44 meV, respectively. Furthermore, we observed gap features of another likely H-depleted H x S superconducting phase in a poorly synthesized hydrogen sulfide sample. Our work offers direct experimental evidence for superconductivity in the hydrogen-rich superconductor H 3 S from a microscopic perspective. It validates the phonon-mediated mechanism of superconducting pairing and provides a foundation for further understanding the origins of high-temperature superconductivity in hydrogen-rich compounds.

『摘要』 研究发现,几种富氢超导体表现出前所未有的高临界温度,这激发了人们对这些材料中超导性本质的研究兴趣。尽管它们的宏观超导特性已经确定,但对其配对机制的微观认识仍不清楚。在本文中,我们通过隧道谱测量表征了高温超导体H3S及其氘对应物D3S的超导能隙结构。隧道谱显示,H3S和D3S均具有完全能隙结构,可用单s波Dynes模型很好地描述,其能隙值2Δ分别约为60 meV和44 meV。此外,我们还在合成不良的硫化氢样品中观察到了另一种可能是氢缺失的HxS超导相的能隙特征。我们的工作从微观角度为富氢超导体H3S中的超导性提供了直接实验证据。它验证了超导配对的声子介导机制,并为进一步理解富氢化合物中高温超导的起源提供了基础。
『总结』 本研究通过隧道谱测量揭示了H3S和D3S的超导能隙结构,为富氢超导体中的超导性提供了实验证据,并支持了声子介导的超导配对机制。
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『Abstract』Membranes are molecular interfaces that compartmentalize cells to control the flow of nutrients and information. These functions are facilitated by diverse collections of lipids, nearly all of which are distributed asymmetrically between the two bilayer leaflets. Most models of biomembrane structure and function include the implicit assumption that these leaflets have similar abundances of phospholipids. Here, we show that this assumption is generally invalid and investigate the consequences of lipid abundance imbalances in mammalian plasma membranes (PMs). Using lipidomics, we report that cytoplasmic leaflets of human erythrocyte membranes have >50% overabundance of phospholipids compared with exoplasmic leaflets. This imbalance is enabled by an asymmetric interleaflet distribution of cholesterol, which regulates cellular cholesterol homeostasis. These features produce unique functional characteristics, including low PM permeability and resting tension in the cytoplasmic leaflet that regulates protein localization.

『摘要』 膜是细胞的分子界面,用于控制营养物质和信息的流动。这些功能由多种脂质共同促进,而这些脂质几乎全都在两层膜叶之间不对称分布。大多数生物膜结构和功能模型都隐含地假设这两层膜叶中的磷脂含量相似。在这里,我们证明了这个假设通常不成立,并研究了哺乳动物质膜(PMs)中脂质含量不平衡的后果。通过脂质组学研究,我们发现人类红细胞膜的细胞质膜叶中的磷脂含量比细胞外膜叶多50%以上。这种不平衡是由胆固醇在两层膜叶之间的不对称分布所实现的,这种分布调节着细胞的胆固醇稳态。这些特征产生了独特的功能特性,包括降低质膜的通透性、细胞质膜叶的低静息张力,以及由此对蛋白质定位的调控。
『总结』 研究发现哺乳动物质膜两层膜叶中磷脂含量并不相似,这种由胆固醇不对称分布导致的不平衡对细胞功能具有重要影响。
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『Abstract』Targeting ubiquitin E3 ligases is therapeutically attractive; however, the absence of an active-site pocket impedes computational approaches for identifying inhibitors. In a large, unbiased biochemical screen, we discover inhibitors that bind a cryptic cavity distant from the catalytic cysteine of the homologous to E6-associated protein C terminus domain (HECT) E3 ligase, SMAD ubiquitin regulatory factor 1 (SMURF1). Structural and biochemical analyses and engineered escape mutants revealed that these inhibitors restrict an essential catalytic motion by extending an α helix over a conserved glycine hinge. SMURF1 levels are increased in pulmonary arterial hypertension (PAH), a disease caused by mutation of bone morphogenetic protein receptor-2 (BMPR2). We demonstrated that SMURF1 inhibition prevented BMPR2 ubiquitylation, normalized bone morphogenetic protein (BMP) signaling, restored pulmonary vascular cell homeostasis, and reversed pathology in established experimental PAH. Leveraging this deep mechanistic understanding, we undertook an in silico machine-learning-based screen to identify inhibitors of the prototypic HECT E6AP and confirmed glycine-hinge-dependent allosteric activity in vitro . Inhibiting HECTs and other glycine-hinge proteins opens a new druggable space.

『摘要』 针对泛素E3连接酶的治疗颇具吸引力;然而,由于缺乏活性位点口袋,利用计算方法鉴定抑制剂受到阻碍。在一项大规模、无偏倚的生化筛选中,我们发现了抑制剂,这些抑制剂结合于与E6相关蛋白C端结构域(HECT)E3连接酶——SMAD泛素调节因子1(SMURF1)的催化半胱氨酸相距甚远的隐蔽空腔。结构分析和生化分析以及设计的逃避突变体显示,这些抑制剂通过在一个保守的甘氨酸铰链上延伸α螺旋来限制一种必要的催化运动。在由骨形态发生蛋白受体-2(BMPR2)突变引起的肺动脉高压(PAH)中,SMURF1水平增加。我们证明,抑制SMURF1可防止BMPR2泛素化,使骨形态发生蛋白(BMP)信号恢复正常,恢复肺动脉血管细胞稳态,并逆转已形成的实验性PAH的病理表现。基于对这一机制的深刻理解,我们采用基于机器学习的计算机筛选方法,鉴定出原型HECT E6AP的抑制剂,并在体外证实了依赖于甘氨酸铰链的变构活性。抑制HECT和其他甘氨酸铰链蛋白为药物开发开辟了新的空间。
『总结』 本研究发现了靶向SMURF1的抑制剂,并通过机制研究揭示了其作用方式,进一步通过计算机筛选拓宽了针对HECT和其他甘氨酸铰链蛋白的药物开发空间。
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『Abstract』How genomic DNA is folded during cell division to form the characteristic rod-shaped mitotic chromosomes essential for faithful genome inheritance is a long-standing open question in biology. Here, we use nanoscale DNA tracing in single dividing cells to directly visualize how the 3D fold of genomic DNA changes during mitosis at scales from single loops to entire chromosomes. Our structural analysis reveals a characteristic genome scaling minimum of 6–8 megabases in mitosis. Combined with data-driven modeling and molecular perturbations, we can show that very large and strongly overlapping loops formed by condensins are the fundamental structuring principle of mitotic chromosomes. These loops compact chromosomes locally and globally to the limit set by chromatin self-repulsion. The characteristic length, density, and increasingly overlapping structure of mitotic loops we observe in 3D fully explain how the rod-shaped mitotic chromosome structure emerges by self-organization during cell division.

『摘要』 在细胞分裂过程中,基因组DNA如何折叠形成对忠实基因组遗传至关重要的特征性杆状有丝分裂染色体,这是生物学中一个长期悬而未决的问题。本研究利用单分裂细胞中的纳米尺度DNA追踪技术,直接可视化有丝分裂过程中基因组DNA从单个环到整个染色体的3D折叠变化。结构分析显示,有丝分裂中基因组的最小特征标度为6~8兆碱基。结合数据驱动建模和分子扰动,我们可以证明由凝聚蛋白形成的非常大且强烈重叠的环是有丝分裂染色体的基本结构原理。这些环使染色体在局部和整体上都压缩至染色质自排斥所设定的极限。我们在3D中观察到的有丝分裂环的特征长度、密度以及越来越重叠的结构,充分解释了杆状有丝分裂染色体结构如何在细胞分裂过程中通过自组织形成。
『总结』 研究揭示了有丝分裂过程中,凝聚蛋白形成的大且重叠的环是染色体结构的基本原理,这些环的特定结构促使杆状有丝分裂染色体通过自组织形成。
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『Abstract』To maintain tissue homeostasis, many cells reside in a quiescent state until prompted to divide. The reactivation of quiescent cells is perturbed with aging and may underlie declining tissue homeostasis and resiliency. The unfolded protein response regulators IRE-1 and XBP-1 are required for the reactivation of quiescent cells in developmentally L1-arrested C. elegans . Utilizing a forward genetic screen in C. elegans , we discovered that macroautophagy targets protein aggregates to lysosomes in quiescent cells, leading to lysosome damage. Genetic inhibition of macroautophagy and stimulation of lysosomes via the overexpression of HLH-30 (TFEB/TFE3) synergistically reduces lysosome damage. Damaged lysosomes require IRE-1/XBP-1 for their repair following prolonged L1 arrest. Protein aggregates are also targeted to lysosomes by macroautophagy in quiescent cultured mammalian cells and are associated with lysosome damage. Thus, lysosome damage is a hallmark of quiescent cells, and limiting lysosome damage by restraining macroautophagy can stimulate their reactivation.

『摘要』 为维持组织稳态,许多细胞处于静止状态,直到被诱导分裂。随着衰老,静止细胞的重新激活会受到干扰,这可能是组织稳态和恢复力下降的原因。未折叠蛋白反应调节因子IRE-1和XBP-1对于发育停滞在L1期的秀丽隐杆线虫中静止细胞的重新激活是必需的。利用秀丽隐杆线虫的正向遗传筛选,我们发现巨自噬作用将蛋白聚集体靶向静止细胞中的溶酶体,导致溶酶体损伤。通过遗传抑制巨自噬作用以及过量表达HLH-30(TFEB/TFE3)刺激溶酶体,可协同减少溶酶体损伤。在长时间L1期停滞后,损伤的溶酶体需要IRE-1/XBP-1进行修复。在静止培养的哺乳动物细胞中,巨自噬作用也将蛋白聚集体靶向溶酶体,并与溶酶体损伤相关。因此,溶酶体损伤是静止细胞的标志,通过抑制巨自噬作用来限制溶酶体损伤可促进其重新激活。
『总结』 研究发现溶酶体损伤是静止细胞的特征,通过抑制巨自噬作用减少溶酶体损伤可促进细胞重新激活。
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『Abstract』Meningeal lymphatics serve as an outlet for cerebrospinal fluid, and their dysfunction is associated with various neurodegenerative conditions. Previous studies have demonstrated that dysfunctional meningeal lymphatics evoke behavioral changes, but the neural mechanisms underlying these changes have remained elusive. Here, we show that prolonged impairment of meningeal lymphatics alters the balance of cortical excitatory and inhibitory synaptic inputs, accompanied by deficits in memory tasks. These synaptic and behavioral alterations induced by lymphatic dysfunction are mediated by microglia, leading to increased expression of the interleukin 6 gene ( Il6 ). IL-6 drives inhibitory synapse phenotypes via a combination of trans - and classical IL-6 signaling. Restoring meningeal lymphatic function in aged mice reverses age-associated synaptic and behavioral alterations. Our findings suggest that dysfunctional meningeal lymphatics adversely impact cortical circuitry through an IL-6-dependent mechanism and identify a potential target for treating aging-associated cognitive decline.

『摘要』 脑膜淋巴管是脑脊液的出口,其功能障碍与多种神经退行性疾病相关。既往研究表明,脑膜淋巴管功能障碍会引发行为变化,但这些变化背后的神经机制一直难以捉摸。本研究发现,脑膜淋巴管长期受损会改变皮层兴奋性突触输入和抑制性突触输入的平衡,同时导致记忆任务表现出现缺陷。淋巴管功能障碍引起的这些突触和行为改变由小胶质细胞介导,导致白细胞介素6基因(Il6)表达增加。白细胞介素-6通过反式信号和传统信号的组合驱动抑制性突触表型。恢复老年小鼠的脑膜淋巴功能可以逆转与年龄相关的突触和行为改变。我们的研究结果表明,脑膜淋巴管功能障碍通过依赖于白细胞介素-6的机制对皮层回路产生不利影响,并确定了一个治疗衰老相关认知衰退的潜在靶点。
『总结』 本研究发现脑膜淋巴管功能障碍通过白细胞介素-6影响皮层突触平衡和行为,为治疗衰老相关的认知衰退提供了新靶点。
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『Abstract』Optical recording of intricate molecular dynamics is becoming an indispensable technique for biological studies, accelerated by the development of new or improved biosensors and microscopy technology. This creates major computational challenges to extract and quantify biologically meaningful spatiotemporal patterns embedded within complex and rich data sources, many of which cannot be captured with existing methods. Here, we introduce activity quantification and analysis (AQuA2), a fast, accurate, and versatile data analysis platform built upon advanced machine-learning techniques. It decomposes complex live-imaging-based datasets into elementary signaling events, allowing accurate and unbiased quantification of molecular activities and identification of consensus functional units. We demonstrate applications across a wide range of biosensors, cell types, organs, animal models, microscopy techniques, and imaging approaches. As exemplar findings, we show how AQuA2 identified drug-dependent interactions between neurons and astroglia, as well as distinct sensorimotor signal propagation patterns in the mouse spinal cord.

『摘要』 光学记录复杂的分子动力学已成为生物学研究中不可或缺的技术,这一发展得益于新型或改进型生物传感器和显微技术的不断进步。然而,从复杂且丰富的数据源中提取和量化具有生物学意义的时空模式带来了重大的计算挑战,其中许多数据无法用现有方法捕获。在此,我们介绍了活动量化与分析(AQuA2),这是一个基于先进机器学习技术构建的快速、准确且多功能的数据分析平台。它可将基于活体成像的复杂数据集分解为基本信号事件,从而实现对分子活动的准确无偏量化以及共识功能单元的识别。我们展示了AQuA2在广泛的生物传感器、细胞类型、器官、动物模型、显微技术和成像方法中的应用。作为示例发现,我们展示了AQuA2如何识别神经元和星形胶质细胞之间的药物依赖性相互作用,以及小鼠脊髓中不同的感觉运动信号传播模式。
『总结』 AQuA2是一个利用先进机器学习技术开发的数据分析平台,可实现对复杂生物数据的快速准确分析,有助于识别分子活动和功能单元。
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『Abstract』Neural reflexes to chemicals in the throat protect the airway from aspiration and infection. Mechanistic understanding of these reflexes remains premature, exemplified by chronic cough—a sensitized cough reflex—being a prevalent unmet clinical need. Here, in mice, a whole-body search for channel synapses—featuring CALHM1/3 channel-mediated neurotransmitter release—and single-cell transcriptomics uncovered subclasses of the Pou2f3 chemosensory cell family in the throat communicating with vagal neurons via this synapse. They express G protein-coupled receptors (GPCRs) for noxious chemicals, T2Rs, which upon stimulation trigger swallow and cough-like expulsive reflexes in the hypopharynx and larynx, respectively. These reflexes were abolished by Calhm3 and Pou2f3 knockout and could be triggered by targeted optogenetic stimulation. Furthermore, aeroallergen exposure augmented CALHM3-dependent expulsive reflex. This study identifies Pou2f3 epithelial cells with channel synapses as chemosensory end organs of airway protective reflexes and sites of their hyperresponsiveness, advancing mechanistic understanding of airway defense programs with distinct therapeutic potential.

『摘要』 喉咙中的化学物质引发的神经反射可以保护气道免受吸入和感染。尽管人们对这些反射的机制有了一定了解,但依然存在不足,例如慢性咳嗽(一种敏感性咳嗽反射)就是一种普遍未满足的临床需求。本研究在小鼠中进行了一项全身性搜索,寻找具有CALHM1/3通道介导的神经递质释放特征的通道突触,并通过单细胞转录组学发现了喉咙中Pou2f3化学感受细胞家族的亚类,这类细胞通过该突触与迷走神经元进行通信。它们表达刺激性化学物质(如苦味物质)的G蛋白偶联受体(GPCRs,即T2Rs),受刺激时会在下咽和喉部触发吞咽和类似咳嗽的排出反射。这些反射在敲除Calhm3和Pou2f3后会消失,并且可以通过靶向光遗传学刺激来触发。此外,气源性过敏原暴露会增强CALHM3依赖性的排出反射。本研究确定了具有通道突触的Pou2f3上皮细胞是气道保护反射的化学感受终末器官以及其高反应性部位,推进了对具有独特治疗潜力的气道防御机制的理解。
『总结』 本研究揭示了Pou2f3上皮细胞通过CALHM1/3通道突触介导气道保护反射,为气道防御机制提供了新的见解和潜在治疗靶点。
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『Abstract』Ferroptosis is a form of cell death due to iron-induced lipid peroxidation. Ferroptosis suppressor protein 1 (FSP1) protects against this death by generating antioxidants, which requires nicotinamide adenine dinucleotide, reduced form (NADH) as a cofactor. We initially uncover that NADH exists at significant levels on cellular membranes and then find that this form of NADH is generated by aldehyde dehydrogenase 7A1 (ALDH7A1) to support FSP1 activity. ALDH7A1 activity also acts directly to decrease lipid peroxidation by consuming reactive aldehydes. Furthermore, ALDH7A1 promotes the membrane recruitment of FSP1, which is instigated by ferroptotic stress activating AMP-activated protein kinase (AMPK) to promote the membrane localization of ALDH7A1 that stabilizes FSP1 on membranes. These findings advance a fundamental understanding of NADH by revealing a previously unappreciated pool on cellular membranes, with the elucidation of its function providing a major understanding of how FSP1 acts and how an aldehyde dehydrogenase protects against ferroptosis.

『摘要』 铁死亡是由于铁介导的脂质过氧化导致的一种细胞死亡形式。铁死亡抑制蛋白1(FSP1)通过生成抗氧化剂来防止这种死亡,这一过程需要还原型烟酰胺腺嘌呤二核苷酸(NADH)作为辅因子。我们最初发现细胞膜上存在大量NADH,随后又发现这种形式的NADH由醛脱氢酶7A1(ALDH7A1)生成,以支持FSP1的活性。ALDH7A1的活性还通过消耗活性醛直接减少脂质过氧化。此外,ALDH7A1可促进FSP1在膜上的募集,这一过程由铁死亡应激激活AMP活化蛋白激酶(AMPK)引发,从而促进ALDH7A1在膜上的定位,进而稳定膜上的FSP1。这些研究结果通过揭示细胞膜上以前未被认识的NADH储存库,增进了对NADH的基本理解,并阐明了FSP1的作用机制以及醛脱氢酶如何防止铁死亡,这具有重大意义。
『总结』 本研究发现细胞膜上的NADH由ALDH7A1生成,可支持FSP1活性并防止铁死亡,增进了对NADH及铁死亡抑制机制的理解。
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『Abstract』Recent breakthroughs in the genetic manipulation of mitochondrial DNA (mtDNA) have enabled precise base substitutions and the efficient elimination of genomes carrying pathogenic mutations. However, reconstituting mtDNA deletions linked to mitochondrial myopathies remains challenging. Here, we engineered mtDNA deletions in human cells by co-expressing end-joining (EJ) machinery and targeted endonucleases. Using mitochondrial EJ (mito-EJ) and mito-ScaI, we generated a panel of clonal cell lines harboring a ∼3.5 kb mtDNA deletion across the full spectrum of heteroplasmy. Investigating these cells revealed a critical threshold of ∼75% deleted genomes, beyond which oxidative phosphorylation (OXPHOS) protein depletion, metabolic disruption, and impaired growth in galactose-containing media were observed. Single-cell multiomic profiling identified two distinct nuclear gene deregulation responses: one triggered at the deletion threshold and another progressively responding to heteroplasmy. Ultimately, we show that our method enables the modeling of disease-associated mtDNA deletions across cell types and could inform the development of targeted therapies.

『摘要』 近期在线粒体DNA(mtDNA)的基因操作方面取得的突破,使得精确的碱基替换和有效消除携带致病突变的基因组成为可能。然而,重建与线粒体肌病相关的mtDNA缺失仍然是一项挑战。本研究通过在人类细胞中共同表达末端连接(EJ)机制和靶向核酸内切酶,构建了mtDNA缺失。利用线粒体EJ(mito-EJ)和mito-ScaI,我们生成了一系列在整个异质性范围内携带约3.5 kb mtDNA缺失的克隆细胞系。对这些细胞的研究发现,约75%的基因组缺失是一个关键阈值,超过该阈值会导致氧化磷酸化(OXPHOS)蛋白减少、代谢紊乱以及在含有半乳糖的培养基中生长受损。单细胞多组学分析发现了两种不同的核基因调控失调反应:一种在缺失阈值时被触发,另一种则随着异质性的增加而逐渐产生反应。最终,我们的研究表明,该方法能够在不同类型的细胞中构建与疾病相关的mtDNA缺失模型,并可为开发靶向疗法提供信息。
『总结』 本研究开发了构建人类细胞中mtDNA缺失的新方法,揭示了与线粒体肌病相关的关键阈值,并展示了其在疾病建模和疗法开发中的应用潜力。
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『Abstract』Advanced gene editing methods have accelerated biomedical discovery and hold great therapeutic promise, but safe and efficient delivery of gene editors remains challenging. In this study, we present a virus-like particle (VLP) system featuring nucleocytosolic shuttling vehicles that retrieve pre-assembled Cas-effectors via aptamer-tagged guide RNAs. This approach ensures preferential loading of fully assembled editor ribonucleoproteins (RNPs) and enhances the efficacy of prime editing, base editing, trans -activators, and nuclease activity coupled to homology-directed repair in multiple immortalized, primary, stem cell, and stem-cell-derived cell types. We also achieve additional protection of inherently unstable prime editing guide RNAs (pegRNAs) by shielding the 3′-exposed end with Csy4/Cas6f, further enhancing editing performance. Furthermore, we identify a minimal set of packaging and budding modules that can serve as a platform for bottom-up engineering of enveloped delivery vehicles. Notably, our system demonstrates superior per-VLP editing efficiency in primary T lymphocytes and two mouse models of inherited retinal disease, highlighting its therapeutic potential.

『摘要』 先进的基因编辑方法加速了生物医学发现,并展现出了巨大的治疗潜力,但基因编辑工具的安全高效递送仍然面临挑战。在本研究中,我们提出了一种类病毒颗粒(VLP)系统,该系统具有核质穿梭载体,可通过适配体标记的引导RNA检索预组装的Cas效应器。这种方法确保了完全组装的编辑核糖核蛋白(RNPs)的优先装载,并提高了多种永生细胞、原代细胞、干细胞和干细胞衍生细胞类型中的精准编辑、碱基编辑、反式激活以及与同源重组修复偶联的核酸酶活性的效率。我们还通过使用Csy4/Cas6f保护3'暴露端,为固有不稳定的精准编辑引导RNA(pegRNA)提供了额外的保护,从而进一步提高了编辑性能。此外,我们确定了一组最小的包装和出芽模块,可作为从头设计包膜递送载体的平台。值得注意的是,我们的系统在原代T淋巴细胞和两种遗传性视网膜疾病的小鼠模型中表现出了优异的每VLP编辑效率,突显了其治疗潜力。
『总结』 本研究开发了一种高效的类病毒颗粒递送系统,实现了基因编辑工具在多种细胞类型中的安全高效递送,并在原发性T淋巴细胞和小鼠模型中验证了其治疗潜力。
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『Abstract』Chimeric antigen receptor (CAR) T cell therapy for solid tumors encounters challenges such as on-target off-tumor toxicity, exhaustion, and limited T cell persistence. Here, we engineer sonogenetic EchoBack-CAR T cells using an ultrasensitive heat-shock promoter screened from a library and integrated with a positive feedback loop from CAR signaling, enabling long-lasting CAR expression upon focused-ultrasound (FUS) stimulation. EchoBack-hGD2CAR T cells, targeting disialoganglioside GD2, exhibited potent cytotoxicity and persistence in 3D glioblastoma (GBM) models. In mice, EchoBack-hGD2CAR T cells suppressed GBM without off-tumor toxicity and outperformed their constitutive counterparts. Single-cell RNA sequencing revealed enhanced cytotoxicity and reduced exhaustion in EchoBack-CAR T cells compared with the standard CAR T cells. This EchoBack design was further adapted to target prostate-specific membrane antigen (EchoBack-PSMACAR) for prostate cancer treatment, demonstrating long-lasting tumor suppression with minimal off-tumor toxicity. Thus, the sonogenetic EchoBack-CAR T cells can serve as a versatile, efficient, and safe strategy for solid tumor treatment.

『摘要』 嵌合抗原受体(CAR)T细胞疗法在治疗实体瘤时面临着诸多挑战,如脱靶毒性、耗竭和T细胞持久性有限等。本研究利用从文库中筛选出的超灵敏热休克启动子,并结合CAR信号的正反馈环路,构建了超声基因EchoBack-CAR T细胞,使CAR在聚焦超声(FUS)刺激下能够持久表达。靶向二唾液酸神经节苷脂GD2的EchoBack-hGD2CAR T细胞在三维胶质母细胞瘤(GBM)模型中表现出强大的细胞毒性和持久性。在小鼠体内,EchoBack-hGD2CAR T细胞能够抑制胶质母细胞瘤,且未产生脱靶毒性,其表现优于常规CAR T细胞。单细胞RNA测序结果显示,与标准CAR T细胞相比,EchoBack-CAR T细胞的细胞毒性增强,耗竭减少。此外,这种EchoBack设计还被改编用于靶向前列腺特异性膜抗原(EchoBack-PSMACAR),以治疗前列腺癌,实现了持久的肿瘤抑制,且脱靶毒性极小。因此,超声基因EchoBack-CAR T细胞可作为一种多功能、高效且安全的实体瘤治疗策略。
『总结』 超声基因EchoBack-CAR T细胞通过超声刺激实现持久CAR表达,有效增强了细胞毒性,减少了耗竭,并在多种实体瘤模型中展现出良好的治疗效果和安全性。
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『Abstract』The organs of many female animals are remodeled by reproduction. Using the mouse intestine, a striking and tractable model of organ resizing, we find that reproductive remodeling is anticipatory and distinct from diet- or microbiota-induced resizing. Reproductive remodeling involves partially irreversible elongation of the small intestine and fully reversible growth of its epithelial villi, associated with an expansion of isthmus progenitors and accelerated enterocyte migration. We identify induction of the SGLT3a transporter in a subset of enterocytes as an early reproductive hallmark. Electrophysiological and genetic interrogations indicate that SGLT3a does not sustain digestive functions or enterocyte health; rather, it detects protons and sodium to extrinsically support the expansion of adjacent Fgfbp1-positive isthmus progenitors, promoting villus growth. Our findings reveal unanticipated specificity to physiological organ remodeling. We suggest that organ- and state-specific growth programs could be leveraged to improve pregnancy outcomes or prevent maladaptive consequences of such growth.

『摘要』 许多雌性动物的器官会因繁殖而发生重塑。利用小鼠肠道这一显著且易于研究的器官大小变化模型,我们发现生殖重塑具有预期性,并且与饮食或微生物群诱导的大小变化不同。生殖重塑包括小肠的部分不可逆伸长和上皮绒毛的完全可逆生长,同时伴随着峡部祖细胞的扩增和肠细胞迁移的加速。我们发现,在一部分肠细胞中诱导表达的SGLT3a转运蛋白是生殖重塑的早期标志。电生理和遗传学研究表明,SGLT3a并不维持消化功能或肠细胞健康;相反,它检测质子和钠离子,以外在方式支持相邻的Fgfbp1阳性峡部祖细胞的扩增,从而促进绒毛生长。我们的研究结果揭示了生理器官重塑的意外特异性。我们认为,可以利用器官和状态特异的生长程序来改善妊娠结局或预防这种生长的不良适应后果。
『总结』 研究发现雌性动物生殖过程中器官重塑具有特异性,与饮食或微生物群无关,SGLT3a转运蛋白在肠细胞中的诱导表达是关键早期标志,这一发现或有助于改善妊娠结局。
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『Abstract』The intestinal immune system maintains tolerance to harmless food proteins and gut microbiota through peripherally derived RORγt Tregs (pTregs), which prevent food intolerance and inflammatory bowel disease. Recent studies suggested that RORγt antigen-presenting cells (APCs), which encompass rare dendritic cell (DC) subsets and type 3 innate lymphoid cells (ILC3s), are key to pTreg induction. Here, we developed a mouse with reduced RORγt APCs by deleting a specific cis -regulatory element of Rorc encoding RORγt. Single-cell RNA sequencing and flow cytometry analyses confirmed the depletion of a RORγt DC subset and ILC3s. These mice showed a secondary reduction in pTregs, impaired tolerance to oral antigens, and an increase in T helper (Th)2 cells. Conversely, ILC3-deficient mice showed no pTregs or Th2 cell abnormalities. Lineage tracing revealed that RORγt DCs share a lymphoid origin with ILC3s, consistent with their similar phenotypic traits. These findings highlight the role of lymphoid RORγt DCs in maintaining intestinal immune balance and preventing conditions like food allergies.

『摘要』 肠道免疫系统通过外周衍生的RORγt调节性T细胞(pTregs)维持对无害食物蛋白和肠道微生物群的耐受性,从而防止食物不耐受和炎症性肠病。近期研究表明,RORγt抗原呈递细胞(APCs),包括罕见的树突状细胞(DC)亚群和3型固有淋巴样细胞(ILC3s),是诱导pTreg的关键。本研究中,我们通过删除编码RORγt的Rorc的特定顺式调控元件,培育出了RORγt APC减少的小鼠。单细胞RNA测序和流式细胞术分析证实了RORγt DC亚群和ILC3的减少。这些小鼠表现出pTreg的二次减少、对口服抗原的耐受性受损以及T辅助(Th)2细胞增加。相比之下,ILC3缺乏的小鼠未出现pTreg或Th2细胞异常。谱系追踪显示,RORγt DC与ILC3具有相同的淋巴系起源,这与它们相似的表型特征一致。这些发现凸显了淋巴系RORγt DC在维持肠道免疫平衡和预防食物过敏等疾病方面的作用。
『总结』 淋巴系RORγt DC对于维持肠道免疫耐受和平衡至关重要,其缺失可能导致食物不耐受和炎症性肠病等问题。
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