前沿速递 | NCS 集萃: 2025-03-07 期 [Up]

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『Abstract』Abstract Loss of early-life microbial diversity is correlated with diabetes, yet mechanisms by which microbes influence disease remain elusive. We report a critical neonatal window in mice when microbiota disruption results in lifelong metabolic consequences stemming from reduced β cell development. We show evidence for the existence of a similar program in humans and identify specific fungi and bacteria that are sufficient for β cell growth. The microbiota also plays an important role in seeding islet-resident macrophages, and macrophage depletion during development reduces β cells. Candida dubliniensis increases β cells in a macrophage-dependent manner through distinctive cell wall composition and reduces murine diabetes incidence. Provision of C. dubliniensis after β cell ablation or antibiotic treatment improves β cell function. These data identify fungi as critical early-life commensals that promote long-term metabolic health.

『摘要』 研究表明,早期微生物多样性的丧失与糖尿病相关,但微生物影响疾病的机制尚不清楚。本文报告了小鼠的一个关键新生儿窗口期,在此期间微生物群落失衡会导致β细胞发育减少,从而产生终身的代谢后果。本文提供了人类中存在类似机制的证据,并确定了可促进β细胞生长的特定真菌和细菌。微生物群在促进胰岛驻留巨噬细胞的形成中也起着重要作用,而发育过程中巨噬细胞的减少会导致β细胞数量下降。白色念珠菌通过其独特的细胞壁成分以巨噬细胞依赖的方式增加β细胞数量,并降低小鼠的糖尿病发病率。在β细胞消融或抗生素治疗后补充白色念珠菌可改善β细胞功能。这些数据表明,真菌是促进长期代谢健康的关键早期共生微生物。
『总结』 早期生活中微生物多样性影响β细胞发育,特定真菌和细菌对维持β细胞数量和功能至关重要,有助于促进长期代谢健康。
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『Abstract』Abstract Cells have evolved mechanisms to distribute ~10 billion protein molecules to subcellular compartments where diverse proteins involved in shared functions must assemble. In this study, we demonstrate that proteins with shared functions share amino acid sequence codes that guide them to compartment destinations. We developed a protein language model, ProtGPS, that predicts with high performance the compartment localization of human proteins excluded from the training set. ProtGPS successfully guided generation of novel protein sequences that selectively assemble in the nucleolus. ProtGPS identified pathological mutations that change this code and lead to altered subcellular localization of proteins. Our results indicate that protein sequences contain not only a folding code but also a previously unrecognized code governing their distribution to diverse subcellular compartments.

『摘要』 细胞已经进化出机制,将约100亿个蛋白质分子分配到亚细胞区室,在那里具有共同功能的不同蛋白质必须组装在一起。在本研究中,我们证明具有共同功能的蛋白质共享氨基酸序列密码,这些密码将它们引导到目标区室。我们开发了一种蛋白质语言模型ProtGPS,该模型能够高性能地预测被排除在训练集之外的人类蛋白质的区室定位。ProtGPS成功指导了选择性组装在细胞核中的新型蛋白质序列的生成。ProtGPS还鉴定出了改变这一密码并导致蛋白质亚细胞定位改变的病理性突变。我们的研究结果表明,蛋白质序列不仅包含折叠密码,还包含一种先前未被识别的、控制其分配到不同亚细胞区室的密码。
『总结』 研究发现具有共同功能的蛋白质共享定位密码,并开发了模型ProtGPS来预测蛋白质亚细胞定位,同时该模型还能指导新型蛋白质序列生成并鉴定出导致蛋白质定位改变的病理性突变。
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『Abstract』Abstract DNA G-quadruplexes (G4s) are non–B-form DNA secondary structures that threaten genome stability by impeding DNA replication. To elucidate how G4s induce replication fork arrest, we characterized fork collisions with preformed G4s in the parental DNA using reconstituted yeast and human replisomes. We demonstrate that a single G4 in the leading strand template is sufficient to stall replisomes by arresting the CMG helicase. Cryo–electron microscopy structures of stalled yeast and human CMG complexes reveal that the folded G4 is lodged inside the central CMG channel, arresting translocation. The G4 stabilizes the CMG at distinct translocation intermediates, suggesting an unprecedented helical inchworm mechanism for DNA translocation. These findings illuminate the eukaryotic replication fork mechanism under normal and perturbed conditions.

『摘要』 研究发现,DNA G-四联体(G4s)是一种非B型DNA二级结构,会阻碍DNA复制,从而威胁基因组稳定性。为阐明G4s如何诱导复制叉停滞,我们使用重构的酵母和人类复制体,表征了亲本DNA中预先形成的G4s与复制叉的碰撞。研究表明,前导链模板中的单个G4就足以通过阻滞CMG解旋酶来使复制体停滞。冷冻电子显微镜下的停滞酵母和人类CMG复合物结构显示,折叠的G4卡在CMG中央通道内,阻止了易位。G4在CMG不同的易位中间态时使其稳定,表明DNA易位存在一种前所未有的螺旋式尺蠖机制。这些发现阐明了正常和扰动条件下真核生物的复制叉机制。
『总结』 研究发现DNA G-四联体能阻滞CMG解旋酶导致复制体停滞,揭示了一种新的DNA易位机制。
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『Abstract』Abstract Methods for making high-spring-index polymer fiber or yarn muscles have required expensive fabrication by wrapping around a mandrel, which limits their practical applications. We demonstrate an inexpensive mandrel-free method for making polymer muscles that can have a spring index of >50 and a contractile tensile stroke exceeding 97%. This method enables the spring index to be varied along a muscle’s length by varying the plying twist, resulting in muscles that transition between homochiral and heterochiral when either heated or cooled. We demonstrate use of these polymer muscles for robots and environmentally driven comfort-adjusting jackets. This mandrel-free method was used to make high-spring-index carbon nanotube yarns for mechanical energy harvesters, self-powered strain sensors, and solvent-driven and electrochemically driven artificial muscles.

『摘要』 制作高弹簧指数聚合物纤维或纱线肌肉的方法需要围绕芯轴进行昂贵的制作,这限制了它们的实际应用。我们展示了一种无需芯轴的廉价制作聚合物肌肉的方法,该方法制作出的聚合物肌肉弹簧指数可超过50,收缩拉伸行程超过97%。通过改变加捻程度,该方法能够使肌肉的弹簧指数沿其长度变化,从而在加热或冷却时使肌肉在同手性和异手性之间转换。我们展示了这些聚合物肌肉在机器人和环境驱动舒适调节夹克中的应用。这种无芯轴方法还被用于制作高弹簧指数的碳纳米管纱线,用于机械能量收集器、自供电应变传感器以及溶剂驱动和电化学驱动的人工肌肉。
『总结』 研究展示了一种无需芯轴的廉价方法制作高弹簧指数聚合物肌肉,该方法能调整肌肉的弹簧指数并实现同/异手性转换,适用于多种应用场景。
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『Abstract』Abstract Manioc—also called cassava and yuca—is among the world’s most important crops, originating in South America in the early Holocene. Domestication for its starchy roots involved a near-total shift from sexual to clonal propagation, and almost all manioc worldwide is now grown from stem cuttings. In this work, we analyze 573 new and published genomes, focusing on traditional varieties from the Americas and wild relatives from herbaria, to reveal the effects of this shift to clonality. We observe kinship over large distances, maintenance of high genetic diversity, intergenerational heterozygosity enrichment, and genomic mosaics of identity-by-descent haploblocks that connect all manioc worldwide. Interviews with Indigenous traditional farmers in the Brazilian Cerrado illuminate how traditional management strategies for sustaining, diversifying, and sharing the gene pool have shaped manioc diversity.

『摘要』 木薯——也被称为木薯根和树薯——是世界上最重要的作物之一,起源于全新世早期的南美洲。木薯因其富含淀粉的根部而被驯化,这一过程几乎完全从有性繁殖转向了无性繁殖,如今全世界的木薯几乎都是通过茎秆扦插种植的。在本研究中,我们分析了573个新基因组和已发表的基因组,重点关注来自美洲的传统品种和来自植物标本馆的野生亲缘种,以揭示这种向无性繁殖转变的影响。我们观察到了远距离的亲缘关系、高遗传多样性的保持、世代间杂合性的丰富,以及全基因组中通过同源下降的单倍型嵌合体,这些嵌合体将全世界的木薯联系在一起。通过对巴西塞拉多地区土著传统农民的访谈,我们了解了他们为维持、多样化和共享基因库而采取的传统管理策略是如何塑造了木薯的多样性。
『总结』 本研究通过分析基因组和访谈土著农民,揭示了木薯从有性繁殖向无性繁殖转变的影响,以及传统管理策略对木薯多样性形成的贡献。
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『Abstract』Abstract The lattice deformation and structural evolution of perovskite films in response to electric fields, temperature, and light limit the operational endurance of solar cells. We mechanically reinforced perovskite thin films by integrating a polymer-coupled monolithic single-layer graphene interface that led to a twofold enhancement in modulus and hardness. The synergistic effect of graphene and poly(methyl methacrylate) restricted photoinduced lattice expansion and decreased the deformation ratio from 0.31 to 0.08%, which minimized the structural damage caused by dynamic lattice evolution. Solar cell devices maintained >97% of their initial power conversion efficiency after maximum power point tracking for >3670 hours under full-spectrum air mass 1.5 global (AM 1.5 G) sunlight at 90°C.

『摘要』 钙钛矿薄膜在电场、温度和光照作用下的晶格变形和结构演变限制了太阳能电池的耐用性。我们通过将聚合物耦合的单层石墨烯界面整合进去,对钙钛矿薄膜进行了机械强化,使其模量和硬度提高了两倍。石墨烯与聚甲基丙烯酸甲酯(poly(methyl methacrylate))的协同作用限制了光致晶格膨胀,将变形率从0.31%降低至0.08%,从而最大程度地减少了动态晶格演变造成的结构损伤。在90°C下,经空气质量1.5全球光谱(AM 1.5 G)太阳光照射,进行最大功率点追踪3670小时后,太阳能电池器件仍保持了97%以上的初始功率转换效率。
『总结』 通过整合聚合物耦合单层石墨烯界面,钙钛矿薄膜的耐用性得到提升,太阳能电池在长时间高温光照下仍保持了高效率。
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『Abstract』Abstract Understanding the capacity of forests to adapt to climate change is of pivotal importance for conservation science, yet this is still widely unknown. This knowledge gap is particularly acute in high-biodiversity tropical forests. Here, we examined how tropical forests of the Americas have shifted community trait composition in recent decades as a response to changes in climate. Based on historical trait-climate relationships, we found that, overall, the studied functional traits show shifts of less than 8% of what would be expected given the observed changes in climate. However, the recruit assemblage shows shifts of 21% relative to climate change expectation. The most diverse forests on Earth are changing in functional trait composition but at a rate that is fundamentally insufficient to track climate change.

『摘要』 了解森林适应气候变化的能力对于保护科学至关重要,然而这一点仍然鲜为人知。这一知识空白在高生物多样性的热带森林中尤为严重。本研究探讨了美洲热带森林近几十年来如何改变群落特征组成以应对气候变化。基于历史上的特征-气候关系,我们发现,总体而言,所研究的功能特征的变化小于根据观察到的气候变化所预期变化的8%。然而,与气候变化预期相比,新入群落的特征变化达到了21%。地球上最多样化的森林正在改变其功能特征组成,但这一变化速度根本不足以应对气候变化。
『总结』 美洲热带森林的功能特征组成正在变化,但变化速度远不足以应对当前的气候变化。
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『Abstract』Abstract Deconstructive transformation of carbon-carbon double bonds (C=C) is a pivotal strategy in synthetic chemistry and drug discovery. Despite the substantial advances in olefin metathesis and ozonolysis for natural product synthesis through C=C double-bond cleavage, the catalytic remodeling of complex molecules through C=C double-bond deconstruction has been underdeveloped. We report a heterogeneous copper-catalyzed C=C double-bond cleavage, which enables the remodeling of complex molecules by converting the carbons on either side of the C=C double bond to carbonyl and cyano groups, respectively. In particular, this method provides an efficient protocol to conveniently transform terpenoids, glycals, steroids, and bioactive molecules to privileged scaffolds with underexplored chemical space.

『摘要』 在合成化学和药物发现领域,碳-碳双键(C=C)的解构转化是一项至关重要的策略。尽管通过C=C双键裂解进行天然产物合成的烯烃复分解和臭氧分解技术已取得重大进展,但通过C=C双键解构对复杂分子进行催化重塑的方法仍有待开发。本研究团队报告了一种异质铜催化的C=C双键裂解方法,能够通过将C=C双键两侧的碳分别转化为羰基和氰基,从而实现对复杂分子的重塑。特别地,该方法提供了一种高效且便捷的方案,可将萜类化合物、糖苷类化合物、类固醇和生物活性分子转化为具有未充分探索化学空间的特权骨架。
『总结』 本研究开发了一种异质铜催化的C=C双键裂解方法,能有效重塑复杂分子并拓展其化学空间。
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『Abstract』Abstract The ultrafast manipulation of molecular states by charge transfer is essential for characterizing and controlling molecular dynamics. In this study, we demonstrated exciton formation in a single molecule through ultrafast electron tunneling processes between a molecule and a metal tip of a scanning tunneling microscope (STM) using a phase-controlled terahertz (THz) pulse. The pronounced luminescence of the well-defined molecular system under the distinct carrier-envelope phase of the THz pulse revealed that sequential state-selective electron-tunneling processes to the frontier molecular orbitals promoted ultrafast exciton formation in the molecule at the STM junction. Furthermore, ultrafast control of exciton formation was achieved using phase- and delay-controlled THz pulse pairs, providing a route for the regulation of molecular dynamics and the emergence of new molecular functions.

『摘要』 通过电荷转移实现的分子状态的超快操控对于表征和控制分子动力学至关重要。在本研究中,我们使用相位控制的太赫兹(THz)脉冲,通过扫描隧道显微镜(STM)的金属探针与分子之间的超快电子隧穿过程,证明了单个分子中激子的形成。在太赫兹脉冲的不同载波包络相位下,定义明确的分子系统发出显著的荧光,表明依次向前沿分子轨道进行的状态选择性电子隧穿过程促进了STM结处分子中超快激子的形成。此外,使用相位和延迟控制的太赫兹脉冲对实现了对激子形成的超快控制,这为调节分子动力学和新分子功能的出现提供了一条途径。
『总结』 本研究通过STM和相位控制的太赫兹脉冲实现了单个分子中激子的超快形成与控制,为分子动力学调控和新分子功能开发提供了新方法。
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『Abstract』Abstract Numerous declines have been documented across insect groups, and the potential consequences of insect losses are dire. Butterflies are the most surveyed insect taxa, yet analyses have been limited in geographic scale or rely on data from a single monitoring program. Using records of 12.6 million individual butterflies from >76,000 surveys across 35 monitoring programs, we characterized overall and species-specific butterfly abundance trends across the contiguous United States. Between 2000 and 2020, total butterfly abundance fell by 22% across the 554 recorded species. Species-level declines were widespread, with 13 times as many species declining as increasing. The prevalence of declines throughout all regions in the United States highlights an urgent need to protect butterflies from further losses.

『摘要』 已有记录显示,多个昆虫类群的数量都在减少,昆虫数量减少带来的潜在后果是可怕的。蝴蝶是被调查最多的昆虫类群,但相关分析要么地理范围有限,要么依赖于单一监测项目的数据。我们根据来自35个监测项目的7.6万余次调查中的1260万只蝴蝶的记录,描述了美国本土蝴蝶的总体和特定物种的数量变化趋势。2000年至2020年间,在554个有记录的物种中,蝴蝶的总数量下降了22%。物种层面的数量减少十分普遍,数量减少的物种数量是数量增加的物种的13倍。全美所有地区蝴蝶数量普遍减少,凸显出保护蝴蝶免受进一步损失的紧迫性。
『总结』 2000至2020年间美国本土蝴蝶数量下降22%,凸显出保护蝴蝶的紧迫性。
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『Abstract』Abstract The synthesis of nitrogen-containing molecules through carbon–nitrogen (C–N) bond formation is critical for the discovery and preparation of medicines, agrochemicals, and materials. Here, we report the direct insertion of a nitrogen atom into unactivated carbon-carbon double bonds to access aza-allenium intermediates, which can be converted either into nitriles or amidine products, depending on the initial alkene substitution pattern. This operationally simple and highly functionally compatible reaction works on a wide range of unactivated alkenes. PIFA, a commercially available and inexpensive hypervalent iodine reagent, is key to this reactivity. Our mechanistic proposal is supported by chemical trapping experiments, which concomitantly demonstrate the utility of our method to access valuable N -heterocycles. Additionally, our method can be used as a general strategy for synthesizing amides and amines, as well as N-labeled molecules.

『摘要』 通过碳-氮(C-N)键的形成合成含氮分子对于药物、农药和材料的发现与制备至关重要。本文报道了一种将氮原子直接插入非活化碳碳双键中形成氮杂烯丙基正离子中间体的方法,该中间体可根据初始烯烃的取代模式转化为腈类或脒类产品。这种操作简单且高度功能兼容的反应适用于多种非活化烯烃。廉价且可商购的超价碘试剂PIFA是实现这一反应的关键。化学捕获实验为我们的机理推测提供了支持,同时证明了该方法在合成有价值的氮杂环化合物方面的实用性。此外,我们的方法还可作为合成酰胺、胺以及氮标记分子的通用策略。
『总结』 本研究报道了一种利用PIFA将氮原子直接插入非活化碳碳双键的新方法,合成了有价值的氮杂环、酰胺、胺及氮标记分子。
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『Abstract』Abstract The regulation of messenger RNA (mRNA) and protein abundances is well-studied, but less is known about the evolutionary processes shaping their relationship. To address this, we derived a new phylogenetic model and applied it to multispecies mammalian data. Our analyses reveal (i) strong stabilizing selection on protein abundances over macroevolutionary time, (ii) mutations affecting mRNA abundances minimally impact protein abundances, (iii) mRNA abundances evolve under selection to align with protein abundances, and (iv) mRNA abundances adapt faster than protein abundances owing to greater mutational opportunity. These conclusions are supported by comparisons of model parameters with independent functional genomic data. By decomposing mutational and selective influences on mRNA-protein dynamics, our approach provides a framework for discovering the evolutionary rules that drive divergence in gene expression.

『摘要』 信使核糖核酸(mRNA)和蛋白质丰度的调控已得到充分研究,但关于塑造两者关系的进化过程却知之甚少。为解决这一问题,我们推导了一个新的系统发育模型,并将其应用于多种哺乳动物的数据。我们的分析揭示:(i)在宏观进化时间上,蛋白质丰度受到强烈的稳定选择;(ii)影响mRNA丰度的突变对蛋白质丰度的影响很小;(iii)mRNA丰度在选择的作用下进化,以与蛋白质丰度保持一致;(iv)由于突变机会更多,mRNA丰度的适应速度快于蛋白质丰度。这些结论通过与独立的功能基因组数据比较模型参数得到了支持。通过分解对mRNA-蛋白质动态变化的突变和选择影响,我们的方法为发现驱动基因表达差异的进化规则提供了一个框架。
『总结』 本研究通过新推导的系统发育模型揭示了mRNA和蛋白质丰度在进化过程中的相互关系及影响,提出了关于两者丰度适应速度和选择压力的新见解。
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『Abstract』Abstract Peroxisomes are vital but often overlooked metabolic organelles. We found that excessive interferon signaling remodeled macrophage peroxisomes. This loss of peroxisomes impaired inflammation resolution and lung repair during severe respiratory viral infections. Peroxisomes were found to modulate lipid metabolism and mitochondrial health in a macrophage type-specific manner and enhanced alveolar macrophage-mediated tissue repair and alveolar regeneration after viral infection. Peroxisomes also prevented excessive macrophage inflammasome activation and IL-1β release, limiting accumulation of KRT8 dysplastic epithelial progenitors following viral injury. Pharmacologically enhancing peroxisome biogenesis mitigated both acute symptoms and post-acute sequelae of COVID-19 (PASC) in animal models. Thus, macrophage peroxisome dysfunction contributes to chronic lung pathology and fibrosis after severe acute respiratory syndrome coronavirus 2 infection.

『摘要』 过氧化物酶体是至关重要但经常被忽视的代谢细胞器。我们发现,过度的干扰素信号会重塑巨噬细胞的过氧化物酶体。这种过氧化物酶体的缺失会损害严重呼吸道病毒感染过程中的炎症消退和肺部修复。研究发现,过氧化物酶体以巨噬细胞类型特异性的方式调节脂质代谢和线粒体健康,并在病毒感染后促进肺泡巨噬细胞介导的组织修复和肺泡再生。过氧化物酶体还能防止巨噬细胞炎症小体过度激活和IL-1β释放,从而限制病毒感染后KRT8发育不良上皮祖细胞的累积。在动物模型中,通过药物促进过氧化物酶体生成可减轻新型冠状病毒感染(COVID-19)的急性症状和急性期后后遗症(PASC)。因此,巨噬细胞过氧化物酶体功能障碍会导致严重急性呼吸综合征冠状病毒2(SARS-CoV-2)感染后的慢性肺部病变和纤维化。
『总结』 巨噬细胞过氧化物酶体功能障碍会损害炎症消退和肺部修复,导致SARS-CoV-2感染后的慢性肺部病变和纤维化。
【闲叙】

『Abstract』Abstract Millions of ribosomes are packed within mammalian cells, yet we lack tools to visualize them in toto and characterize their subcellular composition. In this study, we present ribosome expansion microscopy (RiboExM) to visualize individual ribosomes and an optogenetic proximity-labeling technique (ALIBi) to probe their composition. We generated a super-resolution ribosomal map, revealing subcellular translational hotspots and enrichment of 60 S subunits near polysomes at the endoplasmic reticulum (ER). We found that Lsg1 tethers 60 S to the ER and regulates translation of select proteins. Additionally, we discovered ribosome heterogeneity at mitochondria guiding translation of metabolism-related transcripts. Lastly, we visualized ribosomes in neurons, revealing a dynamic switch between monosomes and polysomes in neuronal translation. Together, these approaches enable exploration of ribosomal localization and composition at unprecedented resolution.

『摘要』 在哺乳动物细胞中,有数百万个核糖体,但我们缺乏工具来对其整体进行可视化并表征其亚细胞成分。在本研究中,我们开发了核糖体膨胀显微镜(RiboExM)来可视化单个核糖体,以及一种光遗传邻近标记技术(ALIBi)来探究其成分。我们生成了超分辨率核糖体图谱,揭示了亚细胞翻译热点以及内质网(ER)附近多聚体周围的60S亚基富集。我们发现Lsg1将60S锚定到内质网上,并调节特定蛋白质的翻译。此外,我们还发现了线粒体处引导代谢相关转录本翻译的核糖体异质性。最后,我们在神经元中可视化了核糖体,揭示了神经元翻译中单聚体和多聚体之间的动态转换。总的来说,这些方法使我们能够以前所未有的分辨率探索核糖体的定位和成分。
『总结』 本研究开发了新工具来可视化并探究哺乳动物细胞中核糖体的定位和成分,发现了翻译热点、60S亚基的定位机制、核糖体在线粒体中的异质性以及神经元中核糖体的动态变化。
【闲叙】

『Abstract』Abstract Global change drives biodiversity shifts worldwide, but these shifts are poorly understood in highly diverse tropical regions. In tropical mountains, plants are mostly expected to migrate upslope in response to warming. To assess this, we analyze shifts in elevation ranges of species in Mesoamerican cloud forests using three decades of species’ occurrence records. Our findings reveal a mean upslope shift of 1.8 to 2.7 meters per year since 1979 driven by the upslope retreat of the less thermophilic montane species. These shifts are mostly accompanied by retreating lower and upper edges attributed to varying degrees of species’ exposure to deforestation and climate change. Our results highlight the vulnerability of cloud forests under global change and the urgency to increase monitoring of species’ responses.

『摘要』 全球变化驱动了全球生物多样性的变化,但在生物多样性极高的热带地区,这些变化却鲜为人知。在热带山区,植物预计主要会因气温上升而向更高海拔迁移。为了评估这一现象,我们利用中美洲云雾林三十年的物种分布记录,分析了物种分布海拔范围的变化。研究发现,自1979年以来,由于不喜热的山地物种向更高海拔退却,物种分布平均每年向更高海拔移动了1.8至2.7米。这些变化大多伴随着物种分布下缘和上缘的后退,这在不同程度上归因于物种遭受的森林砍伐和气候变化。我们的研究结果突显了云雾林在全球变化下的脆弱性,以及加强监测物种反应的紧迫性。
『总结』 全球变化导致中美洲云雾林物种向更高海拔迁移,凸显了云雾林的脆弱性及监测物种反应的紧迫性。
【闲叙】

『Abstract』Neurons in the hippocampus are correlated with different variables, including space, time, sensory cues, rewards and actions, in which the extent of tuning depends on ongoing task demands . However, it remains uncertain whether such diverse tuning corresponds to distinct functions within the hippocampal network or whether a more generic computation can account for these observations . Here, to disentangle the contribution of externally driven cues versus internal computation, we developed a task in mice in which space, auditory tones, rewards and context were juxtaposed with changing relevance. High-density electrophysiological recordings revealed that neurons were tuned to each of these modalities. By comparing movement paths and action sequences, we observed that external variables had limited direct influence on hippocampal firing. Instead, spiking was influenced by online action plans and modulated by goal uncertainty. Our results suggest that internally generated cell assembly sequences are selected and updated by action plans towards deliberate goals. The apparent tuning of hippocampal neuronal spiking to different sensory modalities might emerge due to alignment to the afforded action progression within a task rather than representation of external cues.

『摘要』 海马体中的神经元与不同的变量相关,包括空间、时间、感官提示、奖励和动作,其中调谐的程度取决于当前任务的需求。然而,目前尚不清楚这种多样的调谐是否与海马网络内的不同功能相对应,或者是否存在一种更通用的计算可以解释这些观察结果。为了理清外部驱动提示和内部计算各自的贡献,本研究为小鼠设计了一项任务,将空间、听觉音调、奖励和情境以不同的相关性并列呈现。高密度电生理记录显示,神经元会对这些模式中的每一种进行调谐。通过比较运动路径和动作序列,我们发现外部变量对海马体放电的直接影响有限。相反,放电受在线行动计划的影响,并受目标不确定性的调节。我们的结果表明,内部生成的细胞集群序列由指向明确目标的行动计划选择和更新。海马体神经元放电对不同感觉模式的明显调谐可能是由于与任务内所提供的动作进程相一致,而非对外部提示的表征。
『总结』 海马体神经元的放电调谐更多受内部行动计划和目标不确定性的影响,而非直接反映外部提示。
【闲叙】

『Abstract』For nearly 450 million years, mycorrhizal fungi have constructed networks to collect and trade nutrient resources with plant roots . Owing to their dependence on host-derived carbon, these fungi face conflicting trade-offs in building networks that balance construction costs against geographical coverage and long-distance resource transport to and from roots . How they navigate these design challenges is unclear . Here, to monitor the construction of living trade networks, we built a custom-designed robot for high-throughput time-lapse imaging that could track over 500,000 fungal nodes simultaneously. We then measured around 100,000 cytoplasmic flow trajectories inside the networks. We found that mycorrhizal fungi build networks as self-regulating travelling waves—pulses of growing tips pull an expanding wave of nutrient-absorbing mycelium, the density of which is self-regulated by fusion. This design offers a solution to conflicting trade demands because relatively small carbon investments fuel fungal range expansions beyond nutrient-depletion zones, fostering exploration for plant partners and nutrients. Over time, networks maintained highly constant transport efficiencies back to roots, while simultaneously adding loops that shorten paths to potential new trade partners. Fungi further enhance transport flux by both widening hyphal tubes and driving faster flows along ‘trunk routes’ of the network . Our findings provide evidence that symbiotic fungi control network-level structure and flows to meet trade demands, and illuminate the design principles of a symbiotic supply-chain network shaped by millions of years of natural selection.

『摘要』 在近4.5亿年的时间里,菌根真菌构建了与植物根部收集和交换营养资源的网络。由于这些真菌依赖宿主衍生的碳,因此在构建网络时,它们需要在建设成本、地理覆盖范围和根部长距离资源运输之间取得平衡,而这存在相互冲突的权衡。它们如何应对这些设计挑战尚不清楚。在这里,为了监测活体交易网络的建设,我们构建了一个定制设计的高通量延时成像机器人,能够同时追踪超过50万个真菌节点。随后,我们测量了网络内约10万个细胞质流动轨迹。我们发现,菌根真菌以自我调节的行波形式构建网络——生长尖端的脉冲拉动着一波营养吸收菌丝体的扩张,菌丝体的密度通过融合进行自我调节。这种设计为解决相互冲突的贸易需求提供了解决方案,因为相对较少的碳投资推动了真菌范围向营养枯竭区以外的扩张,从而促进了对植物合作伙伴和营养物质的探索。随着时间的推移,网络保持了对根部的高度恒定运输效率,同时增加了环路,缩短了通往潜在新贸易伙伴的路径。真菌还通过扩大菌丝管和沿着网络的“主干线”驱动更快的流动来进一步增强运输流量。我们的研究结果证明,共生真菌控制网络层面的结构和流动以满足贸易需求,并揭示了数百万年自然选择所形成的共生供应链网络的设计原则。
『总结』 研究发现菌根真菌以自我调节的行波形式构建与植物根部的营养交易网络,通过平衡建设成本和地理覆盖等冲突需求,实现了高效的资源运输和范围扩张。
【闲叙】

『Abstract』Since the onset of the pandemic, many SARS-CoV-2 variants have emerged, exhibiting substantial evolution in the virus’ spike protein , the main target of neutralizing antibodies . A plausible hypothesis proposes that the virus evolves to evade antibody-mediated neutralization (vaccine- or infection-induced) to maximize its ability to infect an immunologically experienced population . Because viral infection induces neutralizing antibodies, viral evolution may thus navigate on a dynamic immune landscape that is shaped by local infection history. Here we developed a comprehensive mechanistic model, incorporating deep mutational scanning data , antibody pharmacokinetics and regional genomic surveillance data, to predict the variant-specific relative number of susceptible individuals over time. We show that this quantity precisely matched historical variant dynamics, predicted future variant dynamics and explained global differences in variant dynamics. Our work strongly suggests that the ongoing pandemic continues to shape variant-specific population immunity, which determines a variant’s ability to transmit, thus defining variant fitness. The model can be applied to any region by utilizing local genomic surveillance data, allows contextualizing risk assessment of variants and provides information for vaccine design.

『摘要』 自疫情爆发以来,许多SARS-CoV-2变异株相继出现,病毒刺突蛋白(中和抗体的主要靶标)发生了显著进化。一个合理的假设是,病毒进化是为了逃避抗体介导的中和作用(由疫苗或感染诱导),以最大限度地提高其感染具有免疫经验人群的能力。由于病毒感染会诱导产生中和抗体,因此病毒进化可能会在由当地感染史塑造的动态免疫环境中进行。本研究开发了一个综合机制模型,该模型结合了深度突变扫描数据、抗体药代动力学和区域基因组监测数据,用于预测随时间变化的变异株特异性易感人群相对数量。研究结果显示,该数量与历史变异株动态精确匹配,可预测未来变异株动态,并解释了变异株动态的全球差异。本研究强烈表明,持续的大流行继续塑造着变异株特异性的群体免疫,这决定了变异株的传播能力,从而决定了变异株的适应度。该模型可通过利用当地基因组监测数据应用于任何地区,有助于对变异株进行风险评估,并为疫苗设计提供信息。
『总结』 本研究开发了一个综合模型,可预测SARS-CoV-2变异株的易感人群数量变化,揭示了病毒进化与群体免疫之间的相互作用,并为疫苗设计提供了重要信息。
【闲叙】

『Abstract』Extreme droughts generally decrease productivity in grassland ecosystems with negative consequences for nature’s contribution to people . The extent to which this negative effect varies among grassland types and over time in response to multi-year extreme drought remains unclear. Here, using a coordinated distributed experiment that simulated four years of growing-season drought (around 66% rainfall reduction), we compared drought sensitivity within and among six representative grasslands spanning broad precipitation gradients in each of Eurasia and North America—two of the Northern Hemisphere’s largest grass-dominated regions. Aboveground plant production declined substantially with drought in the Eurasian grasslands and the effects accumulated over time, while the declines were less severe and more muted over time in the North American grasslands. Drought effects on species richness shifted from positive to negative in Eurasia, but from negative to positive in North America over time. The differing responses of plant production in these grasslands were accompanied by less common (subordinate) plant species declining in Eurasian grasslands but increasing in North American grasslands. Our findings demonstrate the high production sensitivity of Eurasian compared with North American grasslands to extreme drought (43.6% versus 25.2% reduction), and the key role of subordinate species in determining impacts of extreme drought on grassland productivity.

『摘要』 极端干旱通常会降低草原生态系统的生产力,从而对大自然对人类的贡献产生负面影响。多年极端干旱对不同草原类型及不同时间段的负面效应程度差异仍不清楚。本研究开展了一项协调分布式实验,模拟了四年生长期干旱(降雨量减少约66%),比较了欧亚大陆和北美(北半球两个最大的以草为主的区域)内六个具有代表性的、跨广泛降水梯度的草原在干旱下的敏感性以及这些草原之间的敏感性。在欧亚大陆草原,地上植物生产力随干旱而大幅下降,且影响随时间累积;而在北美草原,生产力下降幅度较小,且随时间推移而减弱。在欧亚大陆,干旱对物种丰富度的影响由正转负;而在北美,这种影响则由负转正。这些草原植物生产力的不同变化还伴随着欧亚大陆草原中不常见(次要)植物物种数量的减少以及北美草原中次要物种数量的增加。我们的研究结果表明,与北美草原相比,欧亚大陆草原对极端干旱的生产力敏感性更高(生产力分别降低43.6%和25.2%),同时,次要物种在决定极端干旱对草原生产力影响方面发挥着关键作用。
『总结』 研究发现欧亚大陆草原相比北美草原对极端干旱的生产力敏感性更高,且次要物种对干旱影响草原生产力有关键作用。
【闲叙】

『Abstract』In subsurface methanogenic ecosystems, the ubiquity of methylated-compound-using archaea—methylotrophic methanogens —implies that methylated compounds have an important role in the ecology and carbon cycling of such habitats. However, the origin of these chemicals remains unclear as there are no known energy metabolisms that generate methylated compounds de novo as a major product. Here we identified an energy metabolism in the subsurface-derived thermophilic anaerobe Zhaonella formicivorans that catalyses the conversion of formate to methanol, thereby producing methanol without requiring methylated compounds as an input. Cultivation experiments showed that formate-driven methanologenesis is inhibited by the accumulation of methanol. However, this limitation can be overcome through methanol consumption by a methylotrophic partner methanogen, Methermicoccus shengliensis . This symbiosis represents a fourth mode of mutualistic cross-feeding driven by thermodynamic necessity (syntrophy), previously thought to rely on transfer of hydrogen, formate or electrons . The unusual metabolism and syntrophy provide insights into the enigmatic presence of methylated compounds in subsurface methanogenic ecosystems and demonstrate how organisms survive at the thermodynamic limit through metabolic symbiosis.

『摘要』 在地下产甲烷生态系统中,利用甲基化化合物的古菌——甲基营养型产甲烷菌——无处不在,这表明甲基化化合物在这类生境的生态和碳循环中起着重要作用。然而,这些化学物质的来源尚不清楚,因为目前尚不知道有任何能量代谢过程会以甲基化化合物作为主要产物从头生成它们。本研究在地下衍生的嗜热厌氧菌Zhaonella formicivorans中发现了一种能量代谢过程,该过程能催化甲酸盐转化为甲醇,从而无需甲基化化合物作为输入即可产生甲醇。培养实验表明,甲酸盐驱动的甲醇生成会受到甲醇积累的抑制。然而,当甲醇被甲基营养型共生产甲烷菌——胜利油田甲烷球菌(Methermicoccus shengliensis)消耗时,这种限制就可以被克服。这种共生关系代表了第四种由热力学必要性(共养作用)驱动的互利共生交叉营养模式,而此前人们认为这种模式依赖于氢、甲酸盐或电子的转移。这种不寻常的代谢和共养作用为甲基化化合物在地下产甲烷生态系统中神秘存在提供了见解,并揭示了生物体如何通过代谢共生在热力学极限下生存。
『总结』 研究发现地下嗜热厌氧菌可通过新代谢途径将甲酸盐转化为甲醇,这种代谢和与甲基营养型产甲烷菌的共养作用揭示了甲基化化合物在地下产甲烷生态系统中的来源及生物体在热力学极限下的生存机制。
【闲叙】

『Abstract』Multijunction photovoltaics (PVs) are gaining prominence owing to their superior capability of achieving power conversion efficiencies (PCEs) beyond the radiative limit of single-junction cells , for which improving narrow-bandgap (NBG) tin–lead perovskites is critical for thin-film devices . Here, with a focus on understanding the chemistry of tin–lead perovskite precursor solutions, we find that Sn( ii ) species dominate interactions with precursors and additives and uncover the exclusive role of carboxylic acid in regulating solution colloidal properties and film crystallization and ammonium in improving film optoelectronic properties. Materials that combine these two functional groups, amino acid salts, considerably improve the semiconducting quality and homogeneity of perovskite films, surpassing the effect of the individual functional groups when introduced as part of separate molecules. Our enhanced tin–lead perovskite layer allows us to fabricate solar cells with PCEs of 23.9%, 29.7% (certified 29.26%) and 28.7% for single-junction, double-junction and triple-junction devices, respectively. Our 1-cm triple-junction devices show PCEs of 28.4% (certified 27.28%). Encapsulated triple-junction cells maintain 80% of their initial efficiencies after 860 h maximum power point tracking (MPPT) in ambient. We further fabricate quadruple-junction devices and obtain PCEs of 27.9% with the highest open-circuit voltage of 4.94 V. This work establishes a new benchmark for multijunction PVs.

『摘要』 多结光伏(PV)电池因能够实现超越单结电池辐射极限的功率转换效率(PCE)而日益受到重视,对于薄膜器件而言,改善窄带隙(NBG)锡-铅钙钛矿材料至关重要。本文聚焦于理解锡-铅钙钛矿前驱体溶液的化学性质,我们发现,二价锡物种在前驱体和添加剂的相互作用中占主导地位,并揭示了羧酸在调节溶液胶体性质和薄膜结晶以及铵盐在改善薄膜光电性能方面的独特作用。将这两种官能团结合起来的材料,即氨基酸盐,能显著提高钙钛矿薄膜的半导体质量和均匀性,当它们作为独立分子的一部分引入时,其效果超越了单一官能团。我们利用改良后的锡-铅钙钛矿层制备出了单结、双结和三结器件,其PCE分别达到23.9%、29.7%(认证值为29.26%)和28.7%。我们的1厘米三结器件表现出28.4%的PCE(认证值为27.28%)。封装后的三结电池在环境条件下进行860小时的最大功率点跟踪(MPPT)后,仍保持其初始效率的80%。我们还制备了四结器件,获得了27.9%的PCE,开路电压最高达到4.94伏。这项工作为多结光伏电池树立了新的基准。
『总结』 本研究通过改进锡-铅钙钛矿材料,提高了多结光伏电池的功率转换效率,并树立了新的性能基准。
【闲叙】

『Abstract』UM171 is a potent agonist of ex vivo human haematopoietic stem cell self-renewal . By co-opting KBTBD4, a substrate receptor of the CUL3–RING E3 ubiquitin ligase (CRL3) complex, UM171 promotes the degradation of the LSD1–CoREST corepressor complex, thereby limiting haematopoietic stem cell attrition . However, the direct target and mechanism of action of UM171 remain unclear. Here we show that UM171 acts as a molecular glue to induce high-affinity interactions between KBTBD4 and HDAC1/2 to promote corepressor degradation. Through proteomics and chemical inhibitor studies, we identify the principal target of UM171 as HDAC1/2. Cryo-electron microscopy analysis of dimeric KBTBD4 bound to UM171 and the LSD1–HDAC1–CoREST complex identifies an asymmetric assembly in which a single UM171 molecule enables a pair of KELCH-repeat propeller domains to recruit the HDAC1 catalytic domain. One KBTBD4 propeller partially masks the rim of the HDAC1 active site, which is exploited by UM171 to extend the E3–neosubstrate interface. The other propeller cooperatively strengthens HDAC1 binding through a distinct interface. The overall CoREST–HDAC1/2–KBTBD4 interaction is further buttressed by the endogenous cofactor inositol hexakisphosphate, which acts as a second molecular glue. The functional relevance of the quaternary complex interaction surfaces is demonstrated by base editor scanning of KBTBD4 and HDAC1 . By delineating the direct target of UM171 and its mechanism of action, we reveal how the cooperativity offered by a dimeric CRL3 E3 can be leveraged by a small molecule degrader.

『摘要』 UM171是一种强效的人体造血干细胞体外自我更新激动剂。UM171通过利用CUL3–RING E3泛素连接酶(CRL3)复合物的底物受体KBTBD4,促进LSD1–CoREST共阻遏物复合体的降解,从而限制造血干细胞的消耗。然而,UM171的直接靶点和作用机制尚不清楚。本研究发现,UM171作为一种分子胶,可诱导KBTBD4与HDAC1/2之间发生高亲和力相互作用,从而促进共阻遏物的降解。通过蛋白质组学和化学抑制剂研究,本研究确定HDAC1/2是UM171的主要靶点。对结合UM171的二聚体KBTBD4和LSD1–HDAC1–CoREST复合体进行冷冻电子显微镜分析,本研究发现了一种不对称组装结构,其中一个UM171分子可使一对KELCH重复螺旋桨结构域招募HDAC1催化结构域。一个KBTBD4螺旋桨部分掩盖了HDAC1活性位点的边缘,UM171利用这一点扩展了E3–新底物界面。另一个螺旋桨则通过不同的界面协同增强与HDAC1的结合。内源性辅因子肌醇六磷酸作为第二种分子胶,进一步巩固了整体的CoREST–HDAC1/2–KBTBD4相互作用。通过对KBTBD4和HDAC1进行碱基编辑扫描,本研究证明了四元复合体相互作用表面的功能相关性。本研究通过阐述UM171的直接靶点及其作用机制,揭示了二聚体CRL3 E3提供的协同作用如何被小分子降解剂所利用。
『总结』 本研究发现UM171作为分子胶诱导KBTBD4与HDAC1/2高亲和力结合,促进共阻遏物降解,揭示了UM171的直接靶点和作用机制。
【闲叙】

『Abstract』Intra-atomic orbital hybridization and interatomic bond formation are the two fundamental processes when real atoms are condensed to form matter . Artificial atoms mimic real atoms by demonstrating discrete energy levels attributable to quantum confinement . As such, they offer a solid-state analogue for simulating intra-atomic orbital hybridization and interatomic bond formation. Signatures of interatomic bond formation have been extensively observed in various artificial atoms . However, direct evidence of the intra-atomic orbital hybridization in the artificial atoms remains to be experimentally demonstrated. Here we realize the orbital hybridization in artificial atoms by altering the shape of the artificial atoms. The anisotropy of the confining potential gives rise to the hybridization between quasibound states with different orbital quantum numbers within the artificial atom. These hybridized orbits are directly visualized in real space in our experiment and are well reproduced by both numerical calculations and analytical derivations. Our study opens an avenue for designing artificial matter that cannot be accessed on real atoms through experiments. Moreover, the results obtained inspire the progressive control of quantum states in diverse systems.

『摘要』 原子内轨道杂化和原子间键合是真实原子凝聚形成物质的两个基本过程。人造原子通过表现出由量子限制产生的离散能级来模拟真实原子。因此,它们为模拟原子内轨道杂化和原子间键合提供了固态类似物。原子间键合的特征已在各种人造原子中被广泛观察到。然而,人造原子中原子内轨道杂化的直接证据仍有待实验证实。在本文中,我们通过改变人造原子的形状实现了其轨道杂化。限制势的各向异性导致了人造原子内具有不同轨道量子数的准束缚态之间的杂化。在我们的实验中,这些杂化轨道在真实空间中被直接可视化,并且数值计算和解析推导都能很好地复现该结果。我们的研究为设计无法通过实验在真实原子上实现的人造物质开辟了一条新途径。此外,所获得的结果为在不同系统中逐步控制量子态提供了启发。
『总结』 本研究通过改变人造原子的形状实现了原子内轨道杂化,并观察到杂化轨道,为人造物质的设计和量子态控制提供了新的途径。
【闲叙】

『Abstract』Argonaute proteins are categorized into AGO and PIWI clades. Across most animal species, AGO-clade proteins are widely expressed in various cell types, and regulate normal gene expression . By contrast, PIWI-clade proteins predominantly function during gametogenesis to suppress transposons and ensure fertility . Both clades use nucleic acid guides for target recognition by means of base pairing, crucial for initiating target silencing, often through direct cleavage. AGO-clade proteins use a narrow channel to secure a tight guide–target interaction . By contrast, PIWI proteins feature a wider channel that potentially allows mismatches during pairing, broadening target silencing capability . However, the mechanism of PIWI-mediated target cleavage remains unclear. Here we demonstrate that after target binding, PIWI proteins undergo a conformational change from an ‘open’ state to a ‘locked’ state, facilitating base pairing and enhancing target cleavage efficiency. This transition involves narrowing of the binding channel and repositioning of the PIWI-interacting RNA–target duplex towards the MID-PIWI lobe, establishing extensive contacts for duplex stabilization. During this transition, we also identify an intermediate ‘comma-shaped’ conformation, which might recruit GTSF1, a known auxiliary protein that enhances PIWI cleavage activity . GTSF1 facilitates the transition to the locked state by linking the PIWI domain to the RNA duplex, thereby expediting the conformational change critical for efficient target cleavage. These findings explain the molecular mechanisms underlying PIWI–PIWI-interacting RNA complex function in target RNA cleavage, providing insights into how dynamic conformational changes from PIWI proteins coordinate cofactors to safeguard gametogenesis.

『摘要』 Argonaute蛋白分为AGO和PIWI两大类。在大多数动物物种中,AGO类蛋白在各种细胞类型中广泛表达,并调节正常基因表达。相比之下,PIWI类蛋白主要在配子生成过程中发挥作用,抑制转座子并确保生育能力。这两类蛋白都通过碱基配对的核酸引导物进行靶标识别,这对于启动靶标沉默至关重要,通常是通过直接裂解实现的。AGO类蛋白使用狭窄的通道来确保引导物与靶标之间的紧密结合。相反,PIWI蛋白具有更宽的通道,在配对时可能允许错配,从而扩大了靶标沉默的能力。然而,PIWI介导的靶标裂解机制尚不清楚。本研究表明,在靶标结合后,PIWI蛋白从“开放”状态转变为“锁定”状态,从而促进碱基配对并提高靶标裂解效率。这种转变涉及结合通道的变窄以及PIWI相互作用RNA-靶标双链体向MID-PIWI叶的重新定位,从而建立广泛的接触以稳定双链体。在这一转变过程中,我们还发现了一种中间“逗号状”构象,其可能招募已知的辅助蛋白GTSF1,后者能增强PIWI的裂解活性。GTSF1通过将PIWI结构域与RNA双链体连接,促进向锁定状态的转变,从而加速了对于高效靶标裂解至关重要的构象变化。这些发现解释了PIWI-PIWI相互作用RNA复合物在靶标RNA裂解中的分子机制,为了解PIWI蛋白的动态构象变化如何协调辅助因子以保护配子生成提供了见解。
『总结』 本研究揭示了PIWI蛋白在靶标结合后从“开放”状态转变为“锁定”状态,进而促进靶标裂解的分子机制,并发现GTSF1在这一过程中起辅助作用。
【闲叙】

『Abstract』The neuromodulators dopamine (DA) and serotonin (5-hydroxytryptamine; 5HT) powerfully regulate associative learning . Similarities in the activity and connectivity of these neuromodulatory systems have inspired competing models of how DA and 5HT interact to drive the formation of new associations . However, these hypotheses have not been tested directly because it has not been possible to interrogate and manipulate multiple neuromodulatory systems in a single subject. Here we establish a mouse model that enables simultaneous genetic access to the brain’s DA and 5HT neurons. Anterograde tracing revealed the nucleus accumbens (NAc) to be a putative hotspot for the integration of convergent DA and 5HT signals. Simultaneous recording of DA and 5HT axon activity, together with genetically encoded DA and 5HT sensor recordings, revealed that rewards increase DA signalling and decrease 5HT signalling in the NAc. Optogenetically dampening DA or 5HT reward responses individually produced modest behavioural deficits in an appetitive conditioning task, while blunting both signals together profoundly disrupted learning and reinforcement. Optogenetically reproducing DA and 5HT reward responses together was sufficient to drive the acquisition of new associations and supported reinforcement more potently than either manipulation did alone. Together, these results demonstrate that striatal DA and 5HT signals shape learning by exerting opponent control of reinforcement.

『摘要』 神经调节剂多巴胺(DA)和5-羟色胺(5-hydroxytryptamine;5HT)对联想学习有着强大的调节作用。这些神经调节系统在活动与连接性上的相似性启发了人们对DA和5HT如何相互作用以促进新联想形成的竞争模型。然而,由于无法在同一受试者中探询和操控多个神经调节系统,这些假设一直未得到直接验证。本研究建立了一个小鼠模型,该模型能够同时实现对大脑DA和5HT神经元的基因访问。顺行追踪显示,伏隔核(NAc)可能是DA和5HT会聚信号整合的热点区域。同时记录DA和5HT轴突活动以及基因编码的DA和5HT传感器记录显示,奖励会增加伏隔核中的DA信号并减少5HT信号。在食欲条件反射任务中,单独通过光遗传学方法减弱DA或5HT的奖励反应只会引起轻度的行为缺陷,而同时阻断这两种信号则会严重破坏学习和强化。同时利用光遗传学方法重现DA和5HT的奖励反应足以驱动新联想的获得,并且比单独进行任一种操控更能有效地支持强化。总体而言,这些结果表明,纹状体中的DA和5HT信号通过发挥对强化的对立控制来塑造学习行为。
『总结』 本研究通过小鼠模型发现,纹状体中的多巴胺和5-羟色胺信号通过相互对立地控制强化过程来共同塑造联想学习。
【闲叙】

『Abstract』Tropical deforestation was found to cause large reductions in precipitation using a range of observation-based datasets . However, the limitations of satellite-based space-for-time statistical analysis have hindered understanding of the roles of reshaped mesoscale atmospheric circulation and regional precipitation recycling at different scales. These effects are considered nonlocal effects, which are distinct from the local effects governed by deforestation-induced reductions in evapotranspiration (ET). Here we show reversed precipitation responses to Amazon deforestation across wet and dry seasons. During the wet season, deforested grids experienced a noteworthy increase in precipitation (0.96 mm month per percentage point forest loss), primarily attributed to enhanced mesoscale atmospheric circulation (that is, nonlocal effect). These nonlocal increases weaken with distance from deforested grids, leading to significant precipitation reductions in buffers beyond 60 km. Conversely, during the dry season, precipitation decreases in deforested grids and throughout all analysis buffers, with local effects from reduced ET dominating. Our findings highlight the intricate balance between local effects and nonlocal effects in driving deforestation–precipitation responses across different seasons and scales and emphasize the urgent need to address the rapid and extensive loss of forest in the Amazon region.

『摘要』 基于一系列基于观测的数据集发现,热带森林砍伐会导致降水量大幅减少。然而,基于卫星的空间换时间统计分析的局限性阻碍了人们对改变后的中尺度大气环流和区域降水循环在不同尺度上所起作用的理解。这些影响被视为非局地效应,与由森林砍伐导致的蒸散量(ET)减少所控制的局地效应不同。本文揭示了亚马孙森林砍伐在湿季和干季对降水产生的相反影响。在湿季,森林砍伐区域降水量显著增加(每损失一个百分点的森林面积,月降水量增加0.96毫米),这主要是由于中尺度大气环流增强(即非局地效应)。这种非局地的降水增加随距砍伐区的距离增加而减弱,导致距砍伐区60公里以外的缓冲区降水量显著减少。相反,在干季,砍伐区及其所有分析缓冲区的降水量均有所减少,此时由蒸散量减少引起的局地效应占据主导地位。本研究结果揭示了不同季节和尺度下驱动森林砍伐与降水响应的局地效应与非局地效应之间的微妙平衡,并强调了迫切需要解决亚马孙地区森林快速大面积丧失的问题。
『总结』 研究指出亚马孙森林砍伐在湿季和干季对降水有相反影响,强调了局地效应与非局地效应在不同季节和尺度上的复杂作用,并呼吁紧迫解决亚马孙森林的快速丧失问题。
【闲叙】

『Abstract』Cancer mutations can create neomorphic protein–protein interactions to drive aberrant function . As a substrate receptor of the CULLIN3-RING E3 ubiquitin ligase complex, KBTBD4 is recurrently mutated in medulloblastoma , the most common embryonal brain tumour in children . These mutations impart gain-of-function to KBTBD4 to induce aberrant degradation of the transcriptional corepressor CoREST . However, their mechanism remains unresolved. Here we establish that KBTBD4 mutations promote CoREST degradation through engaging HDAC1/2 as the direct target of the mutant substrate receptor. Using deep mutational scanning, we chart the mutational landscape of the KBTBD4 cancer hotspot, revealing distinct preferences by which insertions and substitutions can promote gain-of-function and the critical residues involved in the hotspot interaction. Cryo-electron microscopy analysis of two distinct KBTBD4 cancer mutants bound to LSD1–HDAC1–CoREST reveals that a KBTBD4 homodimer asymmetrically engages HDAC1 with two KELCH-repeat β-propeller domains. The interface between HDAC1 and one of the KBTBD4 β-propellers is stabilized by the medulloblastoma mutations, which insert a bulky side chain into the HDAC1 active site pocket. Our structural and mutational analyses inform how this hotspot E3–neosubstrate interface can be chemically modulated. First, we unveil a converging shape-complementarity-based mechanism between gain-of-function E3 mutations and a molecular glue degrader, UM171. Second, we demonstrate that HDAC1/2 inhibitors can block the mutant KBTBD4–HDAC1 interface and proliferation of KBTBD4-mutant medulloblastoma cells. Altogether, our work reveals the structural and mechanistic basis of cancer mutation-driven neomorphic protein–protein interactions.

『摘要』 癌症突变可产生新的蛋白质-蛋白质相互作用,从而驱动异常功能。作为CULLIN3-RING E3泛素连接酶复合体的底物受体,KBTBD4在儿童最常见的胚胎性脑瘤——髓母细胞瘤中经常发生突变。这些突变使KBTBD4获得功能,诱导转录共抑制因子CoREST的异常降解。然而,其机制尚不清楚。本研究发现,KBTBD4突变通过使HDAC1/2成为突变底物受体的直接靶点来促进CoREST降解。我们通过深度突变扫描绘制了KBTBD4癌症热点突变的图谱,揭示了插入和替换促进获得功能的不同偏好性以及热点相互作用中的关键残基。对两种不同的KBTBD4癌症突变体与LSD1–HDAC1–CoREST结合的冷冻电子显微镜分析显示,KBTBD4同源二聚体以不对称的方式通过两个KELCH重复β-螺旋桨结构域与HDAC1结合。髓母细胞瘤突变将一个庞大的侧链插入HDAC1活性位点口袋中,从而稳定了HDAC1与其中一个KBTBD4 β-螺旋桨结构域之间的界面。我们的结构和突变分析阐明了这个热点E3–新底物界面如何受到化学调节。首先,我们揭示了在获得功能的E3突变体和分子胶降解剂UM171之间存在一种基于形状互补的趋同机制。其次,我们证明HDAC1/2抑制剂可以阻断突变体KBTBD4–HDAC1界面以及KBTBD4突变髓母细胞瘤细胞的增殖。总的来说,我们的研究揭示了癌症突变驱动的新蛋白质-蛋白质相互作用的结构和机制基础。
『总结』 本研究揭示了KBTBD4癌症突变通过促进CoREST降解驱动异常功能的新机制,并发现HDAC1/2抑制剂可以阻断这一过程,为癌症治疗提供了新的思路。
【闲叙】

『Abstract』The North Pontic Region was the meeting point of the farmers of Old Europe and the foragers and pastoralists of the Eurasian steppe , and the source of migrations deep into Europe . Here we report genome-wide data from 81 prehistoric North Pontic individuals to understand the genetic makeup of its people. North Pontic foragers had ancestry from Balkan and Eastern hunter-gatherers as well as European farmers and, occasionally, Caucasus hunter-gatherers. During the Eneolithic period, a wave of migrants from the Caucasus–Lower Volga area bypassed local foragers to mix in equal parts with Trypillian farmers, forming the people of the Usatove culture around 4500 bce . A temporally overlapping wave of migrants from the Caucasus–Lower Volga blended with foragers instead of farmers to form Serednii Stih people . The third wave was the Yamna—descendants of the Serednii Stih who formed by mixture around 4000 bce and expanded during the Early Bronze Age (3300 bce ). The temporal gap between Serednii Stih and the Yamna is bridged by a genetically Yamna individual from Mykhailivka, Ukraine (3635–3383 bce ), a site of archaeological continuity across the Eneolithic–Bronze Age transition and a likely epicentre of Yamna formation. Each of these three waves of migration propagated distinctive ancestries while also incorporating outsiders, a flexible strategy that may explain the success of the peoples of the North Pontic in spreading their genes and culture across Eurasia .

『摘要』 北庞蒂克地区是欧洲古老农耕民族与欧亚大陆草原上的觅食者和游牧民族的交汇点,也是深入欧洲迁徙的源头。我们对81名史前北庞蒂克个体的全基因组数据进行了报告,以了解其人群的遗传构成。北庞蒂克的觅食者拥有巴尔干半岛和东部狩猎采集者以及欧洲农民的祖先血统,偶尔也会有高加索狩猎采集者的血统。在铜石并用时代,来自高加索-下伏尔加地区的一波移民绕过了当地的觅食者,与特里波利安农民以相同的比例混合,在公元前4500年左右形成了乌萨托夫文化民族。与此同时,另一波来自高加索-下伏尔加地区的移民与觅食者而非农民融合,形成了谢列德尼·斯蒂赫文化民族。第三波是雅姆纳人,他们是谢列德尼·斯蒂赫人的后裔,该民族大约在公元前4000年左右形成,并在青铜时代早期(公元前3300年)扩张。谢列德尼·斯蒂赫文化与雅姆纳文化之间的时间空白,由来自乌克兰米哈伊洛夫卡(公元前3635-3383年)的一个具有雅姆纳人遗传特征的个体填补,该地是跨越铜石并用时代至青铜时代过渡期的考古连续遗址,也可能是雅姆纳文化形成的中心。这三波移民在传播各自独特祖先血统的同时,也吸纳了外来者,这种灵活的策略或许解释了北庞蒂克地区人民为何能够成功地将他们的基因和文化传播到整个欧亚大陆。
『总结』 研究通过分析81名史前北庞蒂克个体的基因组数据,揭示了该地区人群复杂的遗传构成及三次主要的迁徙浪潮,这些迁徙不仅传播了独特的祖先血统,还通过灵活吸纳外来者促进了基因和文化的广泛传播。
【闲叙】

『Abstract』The Casarabe culture (500–1400 ce ), spreading over roughly 4,500 km of the monumental mounds region of the Llanos de Moxos, Bolivia, is one of the clearest examples of urbanism in pre-Columbian (pre-1492 ce ) Amazonia. It exhibits a four-tier hierarchical settlement pattern, with hundreds of monumental mounds interconnected by canals and causeways . Despite archaeological evidence indicating that maize was cultivated by this society , it is unknown whether it was the staple crop and which type of agricultural farming system was used to support this urban-scale society. Here, we address this issue by integration of remote sensing, field survey and microbotanical analyses, which shows that the Casarabe culture invested heavily in landscape engineering, constructing a complex system of drainage canals (to drain excess water during the rainy season) and newly documented savannah farm ponds (to retain water in the dry season). Phytolith analyses of 178 samples from 18 soil profiles in drained fields, farm ponds and forested settings record the singular and ubiquitous presence of maize ( Zea mays ) in pre-Columbian fields and farm ponds, and an absence of evidence for agricultural practices in the forest. Collectively, our findings show how the Casarabe culture managed the savannah landscape for intensive year-round maize monoculture that probably sustained its relatively large population. Our results have implications for how we conceive agricultural systems in Amazonia, and show an example of a Neolithic-like, grain-based agrarian economy in the Amazon.

『摘要』 卡萨拉贝文化(公元 500 年至 1400 年)遍布玻利维亚莫克索斯平原(Llanos de Moxos)纪念性土丘区约 4500 公里的区域,是哥伦布时代前(公元 1492 年前)亚马逊地区城市主义最清晰的例证之一。它呈现出一种四层等级聚落模式,数百个纪念性土丘通过运河和堤道相互连接。尽管有考古证据表明该社会种植了玉米,但尚不清楚玉米是否是其主要作物,也不清楚采用了何种农业耕作制度来支撑这一城市规模的社会。本研究通过整合遥感技术、实地调查和微植物学分析解决了这一问题,结果表明卡萨拉贝文化在景观工程方面投入巨大,建造了复杂的排水渠系统(用于在雨季排掉多余的水)和新发现的热带稀树草原农场池塘(用于在旱季蓄水)。对排水田地、农场池塘和森林环境中的 18 个土壤剖面中的 178 个样本进行的植硅体分析记录了哥伦布时代前田地和农场池塘中玉米(Zea mays)单一且无处不在的存在,以及森林中没有农业活动迹象的情况。总的来说,我们的研究结果表明,卡萨拉贝文化如何通过管理热带稀树草原景观进行全年玉米密集型单一种植,这可能支撑了其相对庞大的人口。我们的研究结果对亚马逊农业系统的构想具有重要意义,并展示了亚马逊地区一个类似新石器时代的、以粮食为基础的农业经济范例。
『总结』 研究表明,卡萨拉贝文化利用复杂的水利工程和全年玉米单一种植支撑了庞大人口,揭示了亚马逊地区类似新石器时代的农业经济模式。
【闲叙】

『Abstract』Antimicrobial compounds are essential for controlling bacterial infections. Stress-induced bacterial tolerance and persisters can undermine antimicrobial activities under laboratory conditions, but their quantitative effects under physiological conditions remain unclear . Here we determined constraints on clearance of Salmonella by antimicrobials in infected mice and tissue-mimicking chemostats. The antibiotics enrofloxacin and ceftriaxone exhibited poor anti- Salmonella activity under both conditions, primarily owing to severe nutrient starvation, which restricted Salmonella replication . Other infection-associated conditions, such as acidic pH, glucose, oxidative stress, nitrosative stress, antimicrobial peptides, osmolarity, oxygen limitation, carbon dioxide and carbonate, as well as drug efflux, toxin–antitoxin modules and cell size had limited effects. A subset of resilient Salmonella appeared as a key obstacle for clearance by enrofloxacin, based on the biphasic decline of Salmonella colony-forming units. However, these data were misleading, because colony formation was confounded by extensive post-exposure killing. More accurate single-cell, real-time assays showed uniformly slow damage, indicating high resilience across the entire Salmonella population. The resulting extensive survival of bulk bacteria minimized the effect of hyper-resilient persisters. Thus, starvation-induced general resilience of Salmonella was the main cause of poor antibiotic clearance. These findings highlight the importance of quantifying antibiotic activity with real-time, single-cell assays under physiological conditions.

『摘要』 抗菌化合物对于控制细菌感染至关重要。在实验室条件下,压力诱导的细菌耐受性和持留菌可破坏抗菌活性,但其在生理条件下的定量影响尚不清楚。本研究确定了在受感染的小鼠和模拟组织的恒化器中,抗菌药物对沙门氏菌清除的限制因素。在这两种条件下,抗生素恩诺沙星和头孢曲松对沙门氏菌的抗菌活性均较差,这主要是由于严重的营养饥饿限制了沙门氏菌的复制。其他与感染相关的条件,如酸性pH值、葡萄糖、氧化应激、硝化应激、抗菌肽、渗透压、氧限制、二氧化碳和碳酸盐以及药物外排、毒素-抗毒素模块和细胞大小的影响均有限。根据沙门氏菌菌落形成单位的双相下降,一部分具有抗性的沙门氏菌似乎是恩诺沙星清除的主要障碍。然而,这些数据具有误导性,因为菌落形成受到了暴露后广泛杀菌作用的干扰。更准确的单细胞实时检测显示沙门氏菌受到的损伤较为一致且缓慢,表明整个沙门氏菌群体都具有高抗性。由此导致的大量细菌存活,使超抗性持留菌的影响降到最低。因此,饥饿诱导的沙门氏菌普遍抗性是抗生素清除效果差的主要原因。这些发现强调了在生理条件下,用实时单细胞检测法定量抗生素活性的重要性。
『总结』 饥饿诱导的沙门氏菌普遍抗性导致抗生素清除效果差,实时单细胞检测有助于在生理条件下准确评估抗生素活性。
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『Abstract』Quantum networks that distribute entanglement among remote nodes will unlock transformational technologies in quantum computing, communication and sensing . However, state-of-the-art networks use only a single optically addressed qubit per node; this constrains both the quantum communication bandwidth and memory resources, greatly impeding scalability. Solid-state platforms provide a valuable resource for multiplexed quantum networking in which multiple spectrally distinguishable qubits can be hosted in nano-scale volumes. Here we harness this resource by implementing a two-node network consisting of several rare-earth ions coupled to nanophotonic cavities . This is accomplished with a protocol that entangles distinguishable Yb ions through frequency-erasing photon detection combined with real-time quantum feedforward. This method is robust to slow optical frequency fluctuations occurring on timescales longer than a single entanglement attempt: a universal challenge amongst solid-state emitters. We demonstrate the enhanced functionality of these multi-emitter nodes in two ways. First, we mitigate the bottlenecks to the entanglement distribution rate through multiplexed entanglement of two remote ion pairs . Second, we prepare multipartite W-states comprising three distinguishable ions as a resource for advanced quantum networking protocols . These results lay the groundwork for scalable quantum networking based on rare-earth ions.

『摘要』 量子网络能够在远程节点之间分发纠缠态,从而在量子计算、通信和传感领域解锁革命性技术。然而,目前最先进的网络在每个节点上仅使用一个光学寻址的量子比特,这限制了量子通信的带宽和存储资源,极大地阻碍了网络的扩展性。固态平台为多路复用量子网络提供了宝贵的资源,其中多个光谱可区分的量子比特可以存在于纳米级体积内。在此,我们通过构建一个由多个与纳米光子腔耦合的稀土离子组成的两节点网络来利用这一资源。这是通过一种协议实现的,该协议通过结合实时量子前馈的频率擦除光子检测来纠缠可区分的镱(Yb)离子。这种方法对于在单次纠缠尝试时间尺度以上发生的慢速光学频率波动具有鲁棒性:这是固态发射体面临的一个普遍挑战。我们通过两种方式展示了这些多发射节点增强的功能。首先,我们通过两个远程离子对的多路复用纠缠来缓解纠缠分发速率的瓶颈。其次,我们制备了由三个可区分离子组成的多方W态,作为高级量子网络协议的资源。这些结果为基于稀土离子的可扩展量子网络奠定了基础。
『总结』 研究展示了利用稀土离子和纳米光子腔构建的两节点量子网络,通过多路复用纠缠和制备多方W态,为可扩展的量子网络奠定了基础。
【闲叙】

『Abstract』Mergers of binary neutron stars emit signals in both the gravitational-wave (GW) and electromagnetic spectra. Famously, the 2017 multi-messenger observation of GW170817 (refs. ) led to scientific discoveries across cosmology , nuclear physics and gravity . Central to these results were the sky localization and distance obtained from the GW data, which, in the case of GW170817, helped to identify the associated electromagnetic transient, AT 2017gfo (ref. ), 11 h after the GW signal. Fast analysis of GW data is critical for directing time-sensitive electromagnetic observations. However, owing to challenges arising from the length and complexity of signals, it is often necessary to make approximations that sacrifice accuracy. Here we present a machine-learning framework that performs complete binary neutron star inference in just 1 s without making any such approximations. Our approach enhances multi-messenger observations by providing: (1) accurate localization even before the merger; (2) improved localization precision by around 30% compared to approximate low-latency methods; and (3) detailed information on luminosity distance, inclination and masses, which can be used to prioritize expensive telescope time. Additionally, the flexibility and reduced cost of our method open new opportunities for equation-of-state studies. Finally, we demonstrate that our method scales to long signals, up to an hour in length, thus serving as a blueprint for data analysis for next-generation ground- and space-based detectors.

『摘要』 双中子星合并会在引力波(GW)和电磁频谱中发出信号。众所周知,2017年对GW170817的多信使观测在宇宙学、核物理学和引力领域取得了科学发现。这些成果的核心是基于引力波数据获得的天区定位和距离,就GW170817而言,这些数据帮助人们在引力波信号发出11小时后确定了相关的电磁瞬变源AT 2017gfo。对引力波数据进行快速分析对于指导时间敏感的电磁观测至关重要。然而,由于信号持续时间长且复杂,往往需要进行近似处理,而这会牺牲准确性。在此,我们提出了一个机器学习框架,该框架仅需1秒即可完成双中子星的完整推断,且无需进行任何近似处理。我们的方法通过以下方式为多信使观测提供了增强:(1)即使在合并前也能进行准确定位;(2)与近似低延迟方法相比,定位精度提高了约30%;(3)提供有关光度距离、倾角和质量的详细信息,这些信息可用于优先安排宝贵的望远镜观测时间。此外,我们的方法具有灵活性和低成本的特点,为状态方程研究开辟了新的机会。最后,我们证明了我们的方法适用于长达一小时的长信号,因此可作为下一代地面和空间探测器数据分析的蓝图。
『总结』 该研究提出了一个机器学习框架,能在1秒内完成对双中子星的完整推断,提高了定位的准确性和精度,为多信使观测和状态方程研究提供了新方法。
【闲叙】

『Abstract』Chirality is a ubiquitous and fundamental asymmetry in nature . Recently, the interaction of chiral objects with spin currents has attracted enormous attention from both scientific and technological perspectives . Of particular interest is the current-driven motion of chiral topological excitations such as chiral magnetic domain walls in chiral three-dimensional magnetic structures that could allow for high-density memory-storage devices. Here we use state-of-the-art multiphoton lithography to create three-dimensional chiral magnetic ribbons and perform current-induced motion of chiral domain walls. The ribbons are designed to have a clockwise or anticlockwise chiral twist with a variable magnitude. We find that domain walls can either pass through the ribbon or are impeded, depending on their chirality and configuration and the geometrical chiral twist of the ribbon. The interplay between the magnetic exchange energy and the geometrical twist generates a torsional field that favours chiral Bloch-type walls rather than the Neel-type wall favoured by the intrinsic magnetic properties of the magnetic ribbon itself. Furthermore, the interplay of spin chirality and chiral twist results in a non-reciprocal domain wall motion, namely, a domain wall filter or diode . Our findings show how the interplay between geometrical and spin chiralities can lead to new functionalities that could allow for innovative chiral spintronics.

『摘要』 手性是自然界中无处不在且根本性的不对称现象。近年来,从科学和技术角度来看,手性物体与自旋流的相互作用引起了广泛关注。尤其值得关注的是,手性三维磁结构中的手性拓扑激发(如手性磁畴壁)的电流驱动运动,这有望应用于高密度存储器件。在此,我们使用最先进的多光子光刻技术创建了三维手性磁带,并实现了电流诱导的手性畴壁运动。这些磁带被设计为具有可变大小的顺时针或逆时针手性扭曲。我们发现,畴壁既可以通过磁带,也可以被阻碍,这取决于它们的手性和构型以及磁带的几何手性扭曲。磁交换能与几何扭曲之间的相互作用产生了一个扭转场,该场有利于手性布洛赫型畴壁,而非磁带本身固有磁性所偏好的奈尔型畴壁。此外,自旋手性与手性扭曲之间的相互作用导致了非互易的畴壁运动,即畴壁滤波器或二极管。我们的研究结果展示了几何手性与自旋手性之间的相互作用如何产生新的功能,从而推动创新的手性自旋电子学发展。
『总结』 研究通过多光子光刻技术创建三维手性磁带,并观察到电流驱动下手性畴壁的运动及非互易性,揭示了几何手性与自旋手性相互作用在创新手性自旋电子学中的潜力。
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『Abstract』Snakebite envenoming remains a devastating and neglected tropical disease, claiming over 100,000 lives annually and causing severe complications and long-lasting disabilities for many more . Three-finger toxins (3FTx) are highly toxic components of elapid snake venoms that can cause diverse pathologies, including severe tissue damage and inhibition of nicotinic acetylcholine receptors, resulting in life-threatening neurotoxicity . At present, the only available treatments for snakebites consist of polyclonal antibodies derived from the plasma of immunized animals, which have high cost and limited efficacy against 3FTxs . Here we used deep learning methods to de novo design proteins to bind short-chain and long-chain α-neurotoxins and cytotoxins from the 3FTx family. With limited experimental screening, we obtained protein designs with remarkable thermal stability, high binding affinity and near-atomic-level agreement with the computational models. The designed proteins effectively neutralized all three 3FTx subfamilies in vitro and protected mice from a lethal neurotoxin challenge. Such potent, stable and readily manufacturable toxin-neutralizing proteins could provide the basis for safer, cost-effective and widely accessible next-generation antivenom therapeutics. Beyond snakebite, our results highlight how computational design could help democratize therapeutic discovery, particularly in resource-limited settings, by substantially reducing costs and resource requirements for the development of therapies for neglected tropical diseases.

『摘要』 蛇咬伤中毒仍然是一种破坏性强且被忽视的热带疾病,每年导致超过10万人死亡,并给更多人造成严重并发症和长期残疾。三指毒素(3FTx)是眼镜蛇科蛇毒中毒性很强的成分,可引起多种病理反应,包括严重组织损伤和抑制烟碱型乙酰胆碱受体,从而产生危及生命的神经毒性。目前,蛇咬伤唯一可用的治疗方法是使用免疫动物血浆中提取的多克隆抗体,但这种方法成本高,且对3FTx的疗效有限。本研究采用深度学习方法,从头设计蛋白质,以结合3FTx家族中的短链和长链α-神经毒素及细胞毒素。经过有限的实验筛选,我们获得了具有显著热稳定性、高结合亲和力且与计算模型几乎达到原子水平一致性的蛋白质设计。设计的蛋白质在体外有效中和了3FTx的所有三个亚家族,并保护小鼠免受致死性神经毒素的攻击。这种效力强、稳定性好且易于制造的毒素中和蛋白可为更安全、成本效益高且易于获得的下一代抗蛇毒疗法奠定基础。除蛇咬伤外,我们的研究结果还突出了计算设计如何通过大幅降低被忽视热带疾病治疗方法的成本和资源需求,来帮助实现治疗发现的民主化,特别是在资源有限的环境中。
『总结』 研究通过深度学习设计出了能中和蛇毒中三指毒素的蛋白质,为开发更安全、成本效益高且广泛可用的抗蛇毒疗法提供了基础,并强调了计算设计在降低被忽视热带疾病治疗成本方面的潜力。
【闲叙】

『Abstract』The Yamnaya archaeological complex appeared around 3300 bc across the steppes north of the Black and Caspian Seas, and by 3000 bc it reached its maximal extent, ranging from Hungary in the west to Kazakhstan in the east. To localize Yamnaya origins among the preceding Eneolithic people, we assembled ancient DNA from 435 individuals, demonstrating three genetic clines. A Caucasus–lower Volga (CLV) cline suffused with Caucasus hunter-gatherer ancestry extended between a Caucasus Neolithic southern end and a northern end at Berezhnovka along the lower Volga river. Bidirectional gene flow created intermediate populations, such as the north Caucasus Maikop people, and those at Remontnoye on the steppe. The Volga cline was formed as CLV people mixed with upriver populations of Eastern hunter-gatherer ancestry, creating hypervariable groups, including one at Khvalynsk. The Dnipro cline was formed when CLV people moved west, mixing with people with Ukraine Neolithic hunter-gatherer ancestry along the Dnipro and Don rivers to establish Serednii Stih groups, from whom Yamnaya ancestors formed around 4000 bc and grew rapidly after 3750–3350 bc . The CLV people contributed around four-fifths of the ancestry of the Yamnaya and, entering Anatolia, probably from the east, at least one-tenth of the ancestry of Bronze Age central Anatolians, who spoke Hittite . We therefore propose that the final unity of the speakers of ‘proto-Indo-Anatolian’, the language ancestral to both Anatolian and Indo-European people, occurred in CLV people some time between 4400 bc and 4000 bc .

『摘要』 雅姆纳亚考古遗址群约公元前3300年出现在黑海和里海北部的草原地带,到公元前3000年达到最大范围,从西部的匈牙利延伸到东部的哈萨克斯坦。为了确定雅姆纳亚人在先前铜石并用时代人群中的起源,我们从435名个体中收集了古DNA,展示了三条遗传渐变线。其中,高加索-下伏尔加(CLV)渐变线充满了高加索狩猎采集者的血统,延伸至高加索地区新石器时代南端的下伏尔加河以及北端的别列日诺夫卡。双向基因流动产生了中间群体,如北高加索的迈科普人和草原上的雷蒙特诺耶人。伏尔加渐变线是由CLV人群与上游具有东欧狩猎采集者血统的人群混合而形成的,由此产生了包括赫瓦林斯克人在内的高度多样化的群体。当CLV人群向西迁移,与第聂伯河和顿河沿岸具有乌克兰新石器时代狩猎采集者血统的人群混合,形成了谢列德尼·斯蒂赫群体,雅姆纳亚人的祖先大约在公元前4000年由此形成,并在公元前3750年至公元前3350年后迅速增长,从而形成了第聂伯渐变线。CLV人群为雅姆纳亚人贡献了大约五分之四的血统,在进入安纳托利亚时(可能从东部进入),为青铜时代中安纳托利亚人(讲赫梯语的人群)贡献了至少十分之一的血统。因此,我们认为,“原始印欧-安纳托利亚语”(安纳托利亚人和印欧语系人群的祖先语言)使用者的最终统一发生在公元前4400年至公元前4000年间的某个时候,统一的人群即为CLV人群。
『总结』 研究表明,雅姆纳亚考古遗址群起源于公元前3300年左右的草原地带,其祖先主要源自高加索-下伏尔加人群,且在公元前4400年至4000年间,这一人群可能促成了“原始印欧-安纳托利亚语”使用者的最终统一。
【闲叙】

『Abstract』Hofstadter’s butterfly, the predicted energy spectrum for non-interacting electrons confined to a two-dimensional lattice in a magnetic field, is one of the most remarkable fractal structures in nature . At rational ratios of magnetic flux quanta per lattice unit cell, this spectrum shows self-similar distributions of energy levels that reflect its recursive construction. For most materials, Hofstadter’s butterfly is predicted under experimental conditions that are unachievable using laboratory-scale magnetic fields . More recently, electrical transport studies have provided evidence for Hofstadter’s butterfly in materials engineered to have artificially large lattice constants , such as those with moire superlattices . Yet, so far, direct spectroscopy of the fractal energy spectrum predicted by Hofstadter nearly 50 years ago has remained out of reach. Here we use high-resolution scanning tunnelling microscopy/spectroscopy (STM/STS) to investigate the flat electronic bands in twisted bilayer graphene (TBG) near the predicted second magic angle , an ideal setting for spectroscopic studies of Hofstadter’s spectrum. Our study shows the fractionalization of flat moire bands into discrete Hofstadter subbands and discerns experimental signatures of self-similarity of this spectrum. Moreover, our measurements uncover a spectrum that evolves dynamically with electron density, showing phenomena beyond that of Hofstadter’s original model owing to the combined effects of strong correlations, Coulomb interactions and the quantum degeneracy of electrons in TBG.

『摘要』 霍夫施塔特蝴蝶结是预测的在磁场中受限于二维晶格的非相互作用电子的能量谱,是自然界中最显著的分形结构之一。在每个晶胞的磁通量子的有理比下,该能谱显示出能级的自相似分布,这反映了其递归结构。对于大多数材料而言,霍夫施塔特蝴蝶结是在实验条件下预测出来的,但这些条件在实验室规模的磁场中是无法实现的。最近,电输运研究已经在人为设计具有较大晶格常数的材料(如具有摩尔超晶格的材料)中提供了霍夫施塔特蝴蝶结存在的证据。然而,迄今为止,近50年前霍夫施塔特预测的分形能谱的直接光谱学研究仍然无法实现。在这里,我们使用高分辨率扫描隧道显微镜/光谱学(STM/STS)来研究扭曲双层石墨烯(TBG)中接近预测的第二个魔角时的平坦电子带,这是光谱学研究霍夫施塔特能谱的理想环境。我们的研究显示了平坦摩尔带分裂为离散的霍夫施塔特子带,并辨别出了该能谱自相似性的实验特征。此外,我们的测量还揭示了一个随电子密度动态演化的能谱,由于扭曲双层石墨烯中强相关性、库仑相互作用和电子量子简并的综合作用,该能谱显示出了超越霍夫施塔特原始模型的现象。
『总结』 本研究利用高分辨率扫描隧道显微镜/光谱学在扭曲双层石墨烯中观察到了霍夫施塔特蝴蝶结的分形能谱特征,并发现该能谱随电子密度动态演化,展现出超越原有模型的新现象。
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『Abstract』Soil alkalinization and global warming are predicted to pose major challenges to agriculture in the future, as they continue to accelerate, markedly reducing global arable land and crop yields . Therefore, strategies for future agriculture are needed to further improve globally cultivated, relatively high-yielding Green Revolution varieties (GRVs) derived from the SEMIDWARF 1 ( SD1 ) gene . Here we propose that precise regulation of the phytohormone gibberellin (GA) to optimal levels is the key to not only confer alkali–thermal tolerance to GRVs, but also to further enhance their yield. Endogenous modulation of ALKALI-THERMAL TOLERANCE 1/2 ( ATT1/2 ), quantitative trait loci encoding GA20-oxidases or exogenous application of GA minimized rice yield loss affected by sodic soils. Mechanistically, high GA concentrations induce reactive oxygen species over-accumulation, whereas low GA concentrations repress the expression of stress-tolerance genes by means of DELLA–NGR5-mediated H3K27me3 methylation. We further showed that ATT1 induces large fluctuations in GA levels, whereas ATT2 is the ideal candidate for fine-tuning GA concentrations to appropriate levels to balance reactive oxygen species and H3K27me3 methylation to improve alkali–thermal tolerance and yield. Thus, ATT2 is expected to be a potential new post-Green Revolution gene that could be harnessed to develop and use marginal lands for sustainable agriculture in the future.

『摘要』 土壤碱化和全球变暖预计将对未来的农业构成重大挑战,随着这两者的持续加速,全球可耕地和作物产量将显著减少。因此,未来的农业战略需要进一步完善源自SEMIDWARF 1(SD1)基因的全球范围内种植的高产绿色革命品种(GRVs)。本文提出,将植物激素赤霉素(GA)精确调节至最佳水平,不仅是赋予GRVs耐碱耐热性的关键,而且还可进一步提高其产量。内源性调节耐碱耐热性1/2(ATT1/2)(编码GA20-氧化酶的数量性状基因座)或外源性施用赤霉素可最大程度地减少盐碱土对水稻产量的影响。从机制上讲,高浓度的赤霉素会诱导活性氧过度积累,而低浓度的赤霉素则会通过DELLA-NGR5介导的H3K27me3甲基化抑制抗逆基因的表达。研究还表明,ATT1会导致赤霉素水平大幅波动,而ATT2是将赤霉素浓度微调至适当水平以平衡活性氧和H3K27me3甲基化从而提高耐碱耐热性和产量的理想候选基因。因此,ATT2有望成为绿色革命之后的一个潜在新基因,可用于开发和利用边际土地,以实现未来农业的可持续发展。
『总结』 调节植物激素赤霉素至最佳水平是提升绿色革命品种耐碱耐热性和产量的关键,ATT2基因有望成为未来农业可持续发展的新基因。
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『Abstract』Investigating glacial isostatic adjustment has been the standard method to decipher Earth’s interior viscosity structure , but such an approach has been rarely applied to other planets because of a lack of observational data . The north polar cap of Mars is the only millions-of-years-old surface feature that can induce measurable surface deformation on this planet, thereby holding clues to its present-day internal viscosity structure . Here we investigate the emplacement of this ice cap by combining thermal evolution models , viscoelastic deformation calculations and radar observations . We show that downward motion of the northern regions is ongoing and can be constrained by analyses of the time-variable gravity field and NASA’s InSight seismic moment rate . Only models with present-day high viscosities (2–6 × 10 Pa s for depths greater than 500 km), strong mantle depletion in radiogenic elements (more than 90%) and thick average crusts (thicker than 40 km) are consistent with the negligible flexure beneath the polar cap seen by radars. The northern lithosphere must deform at less than 0.13 mm per year and have a seismic efficiency less than 0.3 to satisfy gravity and seismic constraints, respectively. Our models show that the north polar cap formed over the last 1.7–12.0 Myr and that glacial isostatic adjustment can be further constrained by future gravity recovery missions to Mars .

『摘要』 研究冰川均衡调整一直是揭示地球内部黏性结构的标准方法,但由于缺乏观测数据,这种方法很少应用于其他行星。火星的北极冰盖是该星球上唯一能引起可测量地表形变的数百万年历史的地表特征,因此掌握着火星现今内部黏性结构的线索。本研究结合了热演化模型、黏弹性形变计算和雷达观测,对这片冰盖的形成进行了调查。研究表明,火星北部地区目前仍在持续向下运动,可通过分析时变重力场和美国国家航空航天局(NASA)的“洞察号”(InSight)地震矩率来对其进行约束。只有当下方深度超过500千米区域的现今黏度高(2×10 Pa s至6×10 Pa s)、放射性生热元素强烈亏损的地幔(超过90%)以及平均地壳较厚(超过40千米)时,才与雷达观测到的北极冰盖下方可忽略不计的挠曲情况一致。为满足重力和地震约束条件,火星北极岩石圈的形变必须低于每年0.13毫米,且地震效率必须低于0.3。我们的模型表明,北极冰盖形成于距今170万至1200万年前,而未来的火星重力恢复任务可进一步约束冰川均衡调整。
『总结』 本研究结合多种方法调查火星北极冰盖的形成,揭示了火星内部的高黏度、地幔特征和地壳厚度,并指出冰川均衡调整可被未来的火星探测任务进一步约束。
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『Abstract』Broadly neutralizing antibodies (bNAbs) show potential to prevent human immunodeficiency virus (HIV-1) infection in humans . However, there are limited data on the antibody concentrations required to prevent infection. Clinical trials of bNAb prophylaxis have demonstrated partial efficacy , but the sampling frequency typically does not allow precise timing of infection events and concurrent antibody levels. Here, using simian immunodeficiency virus (SIV) infection of rhesus macaques, we show that although potent bNAbs can delay the onset of acute viremia, subclinical infections occur while bNAb levels remain high. Serial SIV challenge of monkeys given partially and fully neutralizing bNAbs revealed that ‘viral blips’—low and transient plasma viremia—often occur while serum bNAb concentrations are well above currently accepted protective levels. To understand the precise timing of the infections resulting in such blips, we performed plasma viral sequencing on monkeys that were serially challenged with genetically barcoded SIV after bNAb administration. These analyses showed that subclinical infections occurred in most animals that were given potent bNAb prophylaxis. These subclinical infections occurred while antibody concentrations were 2- to 400-fold higher than the levels required to prevent fully viremic breakthrough infection. This study demonstrates that immunoprophylaxis can mask subclinical infections, which may affect the interpretation of prophylactic HIV-1 bNAb clinical trials.

『摘要』 广泛中和抗体(bNAbs)有潜力预防人类免疫缺陷病毒(HIV-1)感染。然而,关于预防感染所需的抗体浓度数据有限。bNAb预防的临床试验已显示出部分有效性,但采样频率通常无法精确确定感染事件和同时期的抗体水平。在本研究中,我们使用猿免疫缺陷病毒(SIV)感染恒河猴模型,发现虽然强效bNAbs可以延迟急性病毒血症的发作,但在bNAb水平仍然较高时仍会发生亚临床感染。对给予部分和完全中和性bNAbs的猴子进行连续SIV攻击显示,当血清bNAb浓度远高于目前公认的保护水平时,经常会出现“病毒闪烁”——即低水平和短暂的血浆病毒血症。为了了解导致此类病毒闪烁的感染的确切时间,我们对bNAb给药后接受基因条形码SIV连续攻击的猴子进行了血浆病毒测序。这些分析表明,在大多数接受强效bNAb预防的动物中都发生了亚临床感染。这些亚临床感染发生在抗体浓度比预防完全病毒血症突破性感染所需水平高2至400倍时。本研究表明,免疫预防可能会掩盖亚临床感染,这可能影响HIV-1 bNAb预防性临床试验的结果解释。
『总结』 本研究表明强效广泛中和抗体虽能延迟病毒血症发作,但高抗体水平下仍可能发生亚临床感染,这可能影响HIV-1预防性临床试验的结果解读。
【闲叙】

『Abstract』Imaging inflammation holds immense potential for advancing the diagnosis, treatment and prognosis of many conditions . The lack of a specific and sensitive positron emission tomography (PET) probe to detect inflammation is a critical challenge. To bridge this gap, we present CD45-PET imaging, which detects inflammation with exceptional sensitivity and clarity in several preclinical models. Notably, the intensity of the CD45-PET signal correlates robustly with the severity of disease in models of inflammatory lung and bowel diseases, outperforming F-fluorodeoxyglucose PET, the most widely used imaging modality for inflammation globally. Longitudinal CD45-PET imaging further enables precise monitoring of dynamic changes in tissue-specific inflammatory profiles. Finally, we developed a human CD45-PET probe for clinical translation that effectively detects human immune cells in a humanized mouse model. CD45-PET imaging holds substantial clinical promise, offering a tool for guiding diagnostic and therapeutic decisions for inflammatory diseases through a precise, whole-body assessment of the inflammation profiles of individual patients.

『摘要』 成像炎症在推动多种疾病的诊断、治疗和预后方面具有巨大潜力。然而,缺乏特异性和敏感性高的正电子发射断层扫描(PET)探针来检测炎症是一项严峻挑战。为弥补这一空白,我们提出了CD45-PET成像技术,该技术在多种临床前模型中能以极高的敏感性和清晰度检测到炎症。值得注意的是,在炎性肺病和肠病模型中,CD45-PET信号的强度与疾病的严重程度密切相关,其表现优于全球最常用的炎症成像方式F-氟代脱氧葡萄糖PET。此外,纵向CD45-PET成像还能够精确监测组织特异性炎症特征的动态变化。最后,我们开发了一种用于临床转化的人CD45-PET探针,该探针在人源化小鼠模型中能有效检测到人的免疫细胞。CD45-PET成像在临床应用上前景广阔,它能够对单个患者的炎症特征进行精确的全身评估,从而为炎症性疾病的诊断和治疗决策提供指导工具。
『总结』 CD45-PET成像技术能高灵敏度和清晰地检测炎症,与疾病严重程度密切相关,为炎症性疾病的诊疗提供了新工具。
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『Abstract』Despite advancements in wearable technologies , barriers remain in achieving distributed computation located persistently on the human body. Here a textile fibre computer that monolithically combines analogue sensing, digital memory, processing and communication in a mass of less than 5 g is presented. Enabled by a foldable interposer, the two-dimensional pad architectures of microdevices were mapped to three-dimensional cylindrical layouts conforming to fibre geometry. Through connection with helical copper microwires, eight microdevices were thermally drawn into a machine-washable elastic fibre capable of more than 60% stretch. This programmable fibre, which incorporates a 32-bit floating-point microcontroller, independently performs edge computing tasks even when braided, woven, knitted or seam-sewn into garments. The universality of the assembly process allows for the integration of additional functions with simple modifications, including a rechargeable fibre power source that operates the computer for nearly 6 h. Finally, we surmount the perennial limitation of rigid interconnects by implementing two wireless communication schemes involving woven optical links and seam-inserted radio-frequency communications. To demonstrate its utility, we show that garments equipped with four fibre computers, one per limb, operating individually trained neural networks achieve, on average, 67% accuracy in classifying physical activity. However, when networked, inference accuracy increases to 95% using simple weighted voting.

『摘要』 尽管可穿戴技术取得了进步,但要实现持续位于人体上的分布式计算仍存在障碍。本文介绍了一种纺织纤维计算机,它将模拟传感、数字存储、处理和通信功能单片集成在一个质量不到5克的装置中。借助可折叠的中介层,微器件的二维焊盘架构被映射到符合纤维几何形状的三维圆柱布局上。通过与螺旋状铜微线连接,八个微器件被热拉成一根可机洗的弹性纤维,该纤维能够拉伸60%以上。这种可编程纤维内置32位浮点微控制器,即使在编织、机织、针织或缝制成衣物后,也能独立执行边缘计算任务。该组装过程的通用性允许通过简单的修改来整合更多功能,包括一个可充电的纤维电源,使计算机能够运行近6个小时。最后,我们通过实施涉及编织光链路和缝隙插入式射频通信的两种无线通信方案,克服了刚性互连长期存在的局限性。为了证明其实用性,我们展示了配备有四台纤维计算机的服装(每个肢体上一台),它们运行各自经过训练的神经网络,在分类身体活动时的平均准确率为67%。然而,当这些计算机联网后,使用简单的加权投票,推理准确率提高到了95%。
『总结』 研究人员开发了一种集成多种功能的纺织纤维计算机,并展示了其在衣物中的分布式计算、无线通信和活动分类能力。
【闲叙】

『Abstract』Elastocaloric cooling using shape memory alloys (SMAs) has attracted considerable interest as an environmentally friendly, energy-efficient alternative to conventional vapour-compression refrigeration . However, the limited cooling power of existing devices (≤300 W) hampers the commercialization of this technology . Here we constructed a kilowatt-scale elastocaloric cooling device using compressive tubular NiTi in an ‘SMAs in series–fluid in parallel’ architecture, referred to as the multi-cell architecture. A large specific cooling power of 12.3 W g was achieved by the large surface-area-to-volume ratio of thin-walled tubular NiTi at high-frequency operation (3.5 Hz), complemented by graphene nanofluid as an efficient heat transfer agent. Furthermore, the multi-cell architecture ensures a sufficient elastocaloric mass for tight assembly while maintaining a low system fluid pressure. Our device achieves a cooling power of 1,284 W on the fluid side at zero temperature lift during the initial 500,000 cycles, demonstrating the potential of this green cooling technology for a decarbonized future .

『摘要』 使用形状记忆合金 (SMA) 的弹热制冷作为一种环保、高效的制冷方式,已成为传统蒸气压缩制冷的颇具前景的替代品。然而,现有设备的制冷功率有限(≤300瓦),阻碍了这项技术的商业化应用。本文中,我们构建了一种千瓦级的弹热制冷设备,该设备采用“串联SMA-并联流体”架构(即多室架构)中的压缩管状NiTi合金。通过高频操作(3.5赫兹)下薄壁管状NiTi合金的大表面积体积比,加上石墨烯纳米流体作为高效传热剂,实现了12.3瓦/克的高比制冷功率。此外,多室架构在保持系统低流体压力的同时,确保了紧密组装所需的足够弹热质量。我们的设备在最初的50万个循环中,在零温度提升的情况下,流体侧实现了1284瓦的制冷功率,展示了这种绿色制冷技术在未来脱碳方面的潜力。
『总结』 本文构建了一种采用多室架构和石墨烯纳米流体的高效千瓦级弹热制冷设备,展示了其在环保制冷领域的商业化应用潜力。
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『Abstract』Low temperature severely limits the growth, yield, and geographical distribution of maize ( Zea mays L.). How maize adapts to cold climates remains largely unclear. Here, we identify a basic helix-loop-helix (bHLH) transcription factor, COLD-RESPONSIVE OPERATION LOCUS 1 (COOL1), as a crucial regulator of maize cold tolerance through genome-wide association studies. Natural variations in the COOL1 promoter affect the binding affinity of ELONGATED HYPOCOTYL5 (HY5), a transcriptional factor repressing COOL1 transcription. COOL1, in turn, negatively regulates downstream cold-responsive genes, thereby modulating cold tolerance. Moreover, calcium-dependent protein kinase CPK17 translocates to the nucleus and stabilizes COOL1 in response to cold stress. Intriguingly, the cold-tolerant allele of COOL1 is predominantly distributed in northern high latitudes with cold climates. This study defines a previously unknown pathway by which the COOL1-centered module regulates cold tolerance for high latitudinal adaptation in maize.

『摘要』 低温严重限制玉米(Zea mays L.)的生长、产量和地理分布。然而,玉米如何适应寒冷气候仍不清楚。本研究通过全基因组关联研究,确定了一个basic helix-loop-helix(bHLH)转录因子——冷响应操作位点1(COOL1),它是玉米耐寒性的关键调控因子。COOL1启动子的自然变异会影响转录因子ELONGATED HYPOCOTYL5(HY5)的结合亲和力,而HY5会抑制COOL1的转录。COOL1则会负向调节下游冷响应基因,从而调节耐寒性。此外,在冷胁迫下,钙依赖蛋白激酶CPK17会转移到细胞核中并稳定COOL1。有趣的是,耐寒型COOL1等位基因主要分布在气候寒冷的高纬度北方地区。本研究确定了一个以COOL1为中心的模块调节玉米高纬度适应耐寒性的新途径。
『总结』 本研究发现了COOL1转录因子是玉米耐寒性的关键调控因子,并阐明了其在高纬度适应中的新途径。
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『Abstract』Coronavirus fusion with and entry into the host cell depends on viral spike, which acts as a crucial component of viral infection. However, the lack of receptor-activated spike intermediate conformation has hindered a comprehensive understanding of spike-induced membrane fusion. Here, we captured an angiotensin-converting enzyme 2 (ACE2)-induced early fusion intermediate conformation (E-FIC) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike in which heptad repeat 1 (HR1) in S2 has ejected while S1 remains attached. This E-FIC can transition to the late FIC after S2′ cleavage. Leveraging this discovery, we designed an E-FIC-targeted dual-functional antiviral protein, AL5E. AL5E effectively inactivated ACE2-using coronaviruses and inhibited their infection, outperforming a mono-functional antiviral in protecting animals against these coronaviruses. This study has identified the E-FIC and used it as a target for the development of a dual-functional antiviral for the prevention and treatment of ACE2-using coronavirus infection.

『摘要』 冠状病毒与宿主细胞的融合和进入依赖于病毒刺突蛋白,这是病毒感染的关键组分。然而,由于缺乏受体活化的刺突蛋白中间构象,阻碍了人们对刺突蛋白诱导膜融合的全面理解。本研究捕获了血管紧张素转换酶2(ACE2)诱导的严重急性呼吸综合征冠状病毒2(SARS-CoV-2)刺突蛋白的早期融合中间构象(E-FIC),其中S2中的七肽重复序列1(HR1)已弹出,而S1仍保持附着状态。S2'裂解后,这种E-FIC可以转变为晚期FIC。基于这一发现,研究团队设计了一种针对E-FIC的双功能抗病毒蛋白AL5E。AL5E有效灭活了使用ACE2的冠状病毒并抑制了其感染,在保护动物免受这些冠状病毒感染方面优于单功能抗病毒药物。本研究鉴定出了E-FIC,并将其作为开发双功能抗病毒药物以预防和治疗使用ACE2的冠状病毒感染的靶点。
『总结』 本研究发现SARS-CoV-2刺突蛋白的早期融合中间构象,并基于此设计了一种双功能抗病毒蛋白AL5E,有效对抗使用ACE2的冠状病毒。
【闲叙】

『Abstract』Cancer is the leading cause of death from disease in children. Survival depends not only on surgery, cytostatic drugs, and radiation but also on systemic immune responses. Factors influencing these immune responses in children of different ages and tumor types are unknown. Novel immunotherapies can enhance anti-tumor immune responses, but few children have benefited, and markers of effective responses are lacking. Here, we present a systems-level analysis of immune responses in 191 children within a population-based cohort with diverse tumors and reveal that age and tumor type shape immune responses differently. Systemic inflammation and cytotoxic T cell responses correlate with tumor mutation rates and immune cell infiltration. Clonally expanded T cell responses are rarely detected in blood or tumors at diagnosis but are sometimes elicited during treatment. Expanded T cells are similarly regulated in children and adults with more immunogenic cancers. This research aims to facilitate the development of precision immunotherapies for children with cancer.

『摘要』 癌症是儿童疾病死亡的主要原因。儿童的存活不仅取决于手术、细胞抑制剂和放疗,还取决于全身免疫反应。影响不同年龄和不同类型的肿瘤儿童免疫反应的因素尚不清楚。新型免疫疗法可以增强抗肿瘤免疫反应,但获益的儿童寥寥无几,并且缺乏有效反应的标志物。本文基于人群的队列研究,对191名患有不同肿瘤的儿童进行了免疫系统水平分析,发现年龄和肿瘤类型对免疫反应的影响不同。全身性炎症和细胞毒性T细胞反应与肿瘤的突变率和免疫细胞浸润相关。在诊断时,很少在血液或肿瘤中检测到克隆性扩增的T细胞反应,但有时在治疗过程中会引发。在患有免疫原性较强癌症的儿童和成人中,扩增的T细胞受到类似的调控。本研究旨在促进针对儿童癌症的精准免疫疗法的发展。
『总结』 本研究通过对191名患有不同肿瘤儿童的免疫系统分析,发现年龄和肿瘤类型影响免疫反应,提出了促进儿童癌症精准免疫疗法发展的新方向。
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『Abstract』Biocatalytic cascades with spatial proximity can orchestrate multistep pathways to form metabolic highways, which enhance the overall catalytic efficiency. However, the effect of spatial organization on catalytic activity is poorly understood, and multienzyme architectural engineering with predictable performance remains unrealized. Here, we developed a standardized framework, called iMARS, to rapidly design the optimal multienzyme architecture by integrating high-throughput activity tests and structural analysis. The approach showed potential for industrial-scale applications, with artificial fusion enzymes designed by iMARS significantly improving the production of resveratrol by 45.1-fold and raspberry ketone by 11.3-fold in vivo , as well as enhancing ergothioneine synthesis in fed-batch fermentation. In addition, iMARS greatly enhanced the in vitro catalytic efficiency of the multienzyme complexes for PET plastic depolymerization and vanillin biosynthesis. As a generalizable and flexible strategy at molecular level, iMARS could greatly facilitate green chemistry, synthetic biology, and biomanufacturing.

『摘要』 空间邻近的生物催化级联可以协调多步途径以形成代谢高速通道,从而提高整体催化效率。然而,人们对空间组织对催化活性的影响知之甚少,具有可预测性能的多酶结构工程尚未实现。在此,我们开发了一个名为iMARS的标准化框架,通过整合高通量活性测试和结构分析,快速设计出最优的多酶结构。该方法在工业规模应用中展现出潜力,iMARS设计的人工融合酶在体内显著提高了白藜芦醇的产量(45.1倍)和覆盆子酮的产量(11.3倍),并且在补料分批发酵中增强了麦角硫因的合成。此外,iMARS极大地提高了多酶复合物在体外催化PET塑料解聚和香草醛生物合成方面的效率。作为一种在分子层面可推广且灵活的策略,iMARS可极大地促进绿色化学、合成生物学和生物制造的发展。
『总结』 研究团队开发了iMARS标准化框架,能快速设计最优多酶结构,提高催化效率,并在多种生物制造和化学应用中展现了显著提升效果。
【闲叙】

『Abstract』The amphipod Hirondellea gigas is a dominant species inhabiting the deepest part of the ocean (∼6,800–11,000 m), but little is known about its genetic adaptation and population dynamics. Here, we present a chromosome-level genome of H. gigas , characterized by a large genome size of 13.92 Gb. Whole-genome sequencing of 510 individuals from the Mariana Trench indicates no population differentiation across depths, suggesting its capacity to tolerate hydrostatic pressure across wide ranges. H. gigas in the West Philippine Basin is genetically divergent from the Mariana and Yap Trenches, suggesting genetic isolation attributed to the geographic separation of hadal features. A drastic reduction in effective population size potentially reflects glacial-interglacial changes. By integrating multi-omics analysis, we propose host-symbiotic microbial interactions may be crucial in the adaptation of H. gigas to the extremely high-pressure and food-limited environment. Our findings provide clues for adaptation to the hadal zone and population genetics.

『摘要』 两足动物Hirondellea gigas是栖息在海洋最深处(约6800~11000米)的优势物种,但其遗传适应性和种群动态尚不清楚。本研究获得了H. gigas的染色体级基因组,其基因组大小达139.2亿碱基对。对来自马里亚纳海沟的510个个体进行全基因组测序,结果表明不同深度的种群之间没有分化,表明H. gigas能够在很大范围内耐受静水压。西菲律宾海盆中的H. gigas与马里亚纳海沟和雅浦海沟的H. gigas存在遗传差异,表明由于海沟特征的地理隔离而产生了遗传隔离。有效种群规模的急剧减少可能反映了冰期-间冰期的变化。通过整合多组学分析,本研究推测宿主-共生微生物的相互作用对于H. gigas适应极端高压和食物有限的环境至关重要。本研究结果为适应海沟环境和种群遗传学提供了线索。
『总结』 本研究揭示了H. gigas的染色体级基因组特征及其适应深海环境的遗传机制,并发现了其种群动态和遗传差异。
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『Abstract』The nervous system needs to balance the stability of neural representations with plasticity. It is unclear what the representational stability of simple well-rehearsed actions is, particularly in humans, and their adaptability to new contexts. Using an electrocorticography brain-computer interface (BCI) in tetraplegic participants, we found that the low-dimensional manifold and relative representational distances for a repertoire of simple imagined movements were remarkably stable. The manifold’s absolute location, however, demonstrated constrained day-to-day drift. Strikingly, neural statistics, especially variance, could be flexibly regulated to increase representational distances during BCI control without somatotopic changes. Discernability strengthened with practice and was BCI-specific, demonstrating contextual specificity. Sampling representational plasticity and drift across days subsequently uncovered a meta-representational structure with generalizable decision boundaries for the repertoire; this allowed long-term neuroprosthetic control of a robotic arm and hand for reaching and grasping. Our study offers insights into mesoscale representational statistics that also enable long-term complex neuroprosthetic control.

『摘要』 神经系统需要在神经表征的稳定性和可塑性之间取得平衡。目前尚不清楚简单的熟练动作(尤其是在人类中)的表征稳定性如何,也不清楚这些动作对新情境的适应能力如何。我们使用脑电皮层描记术脑机接口(BCI)对四肢瘫痪的参与者进行了研究,发现一组简单想象运动的低维流形和相对表征距离非常稳定。然而,流形的绝对位置表现出有限的逐日漂移。值得注意的是,在不改变体表感觉区域分布的情况下,神经统计数据(特别是方差)可以灵活调节,以增加BCI控制期间的表征距离。可分辨性随着练习而增强,且具有BCI特异性,表现出情境特异性。连续多天对表征可塑性和漂移进行采样后,我们发现了一种具有通用决策边界的元表征结构,该结构能够实现机器人手臂和手部的长期神经假肢控制,以完成伸展和抓握动作。我们的研究提供了对中层表征统计数据的见解,这些统计数据也能实现长期的复杂神经假肢控制。
『总结』 研究表明人类神经系统能通过灵活调节神经统计数据来平衡表征稳定性与可塑性,实现了机器人手臂和手部的长期神经假肢控制。
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『Abstract』Systematic exploration of the hadal zone, Earth’s deepest oceanic realm, has historically faced technical limitations. Here, we collected 1,648 sediment samples at 6–11 km in the Mariana Trench, Yap Trench, and Philippine Basin for the Mariana Trench Environment and Ecology Research (MEER) project. Metagenomic and 16S rRNA gene amplicon sequencing generated the 92-Tbp MEER dataset, comprising 7,564 species (89.4% unreported), indicating high taxonomic novelty. Unlike in reported environments, neutral drift played a minimal role, while homogeneous selection (HoS, 50.5%) and dispersal limitation (DL, 43.8%) emerged as dominant ecological drivers. HoS favored streamlined genomes with key functions for hadal adaptation, e.g., aromatic compound utilization (oligotrophic adaptation) and antioxidation (high-pressure adaptation). Conversely, DL promoted versatile metabolism with larger genomes. These findings indicated that environmental factors drive the high taxonomic novelty in the hadal zone, advancing our understanding of the ecological mechanisms governing microbial ecosystems in such an extreme oceanic environment.

『摘要』 历史上,对地球最深海洋区域——超深渊带的系统探索一直面临技术限制。本研究为马里亚纳海沟环境与生态研究(MEER)项目,在马里亚纳海沟、雅浦海沟和菲律宾海盆6~11千米深处采集了1648份沉积物样本。通过宏基因组学和16S rRNA基因扩增子测序,我们获得了92 Tb大小的MEER数据集,其中包含7564个物种(89.4%为新物种),这表明该区域具有很高的分类学新颖性。与已报道的环境不同,在此环境中,中性漂变的作用微乎其微,而同质选择(HoS,占50.5%)和扩散限制(DL,占43.8%)成为主要的生态驱动因素。同质选择倾向于具有超深渊适应关键功能(如芳香化合物利用——寡营养适应,和抗氧化——高压适应)的精简基因组。相反,扩散限制则促进了具有更大基因组的多样化代谢。这些发现表明,环境因素驱动了超深渊带的高分类学新颖性,增进了我们对这种极端海洋环境中微生物生态系统生态机制的理解。
『总结』 研究通过大量沉积物样本分析,揭示了超深渊带微生物生态系统的高分类学新颖性及其主要生态驱动因素。
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『Abstract』The deep sea, especially hadal zones, characterized by high-hydrostatic pressure, low temperatures, and near-total darkness, present some of the most challenging environments for life on Earth. However, teleost fish have successfully colonized these extreme habitats through complex adaptations. We generated genome assemblies of 12 species, including 11 deep-sea fishes. Our findings reconstructed the teleost deep-sea colonization history and revealed the overall impact of the deep-sea environment on fishes. Interestingly, our results question the previously assumed linear correlation between trimethylamine oxide (TMAO) content and depth. By contrast, we observed a convergent aa replacement in the rtf1 gene in most deep-sea fishes under 3,000 m, and in vitro experiments suggest that this mutation can influence transcriptional efficiency, which is likely to be advantageous in the deep-sea environment. Moreover, our study underlines the pervasive impact of human activities, as we detected the presence of persistent organic pollutants in species from the Mariana Trench.

『摘要』 深海,尤其是海沟区,以高静水压、低温和几乎完全黑暗为特征,是地球上生命面临的最具挑战性的环境之一。然而,硬骨鱼类通过复杂的适应机制成功地在这些极端栖息地中繁衍生息。我们为12个物种(包括11种深海鱼类)生成了基因组组装。我们的研究结果重构了硬骨鱼类的深海殖民历史,并揭示了深海环境对鱼类的整体影响。有趣的是,我们的研究结果对先前关于三甲胺氧化物(TMAO)含量与深度之间存在线性相关性的假设提出了质疑。相反,我们在大多数生活在3000米以下的深海鱼类中观察到了rtf1基因中的一个趋同氨基酸替换,体外实验表明这种突变可以影响转录效率,这在深海环境中可能是有利的。此外,我们的研究还强调了人类活动的广泛影响,因为我们在马里亚纳海沟的物种中检测到了持久性有机污染物的存在。
『总结』 本研究通过基因组分析揭示了硬骨鱼类在深海极端环境中的适应机制,对TMAO含量与深度的关系提出了新见解,并发现了rtf1基因突变对深海鱼类的潜在益处,同时指出了人类活动对深海生态的影响。
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『Abstract』Little is known about metabolic vulnerabilities in oncogene-driven lung cancer. Here, we perform a phosphoproteomic screen in anaplastic lymphoma kinase ( ALK )-rearranged (“ALK+”) patient-derived cell lines and identify guanylate kinase 1 (GUK1), a guanosine diphosphate (GDP)-synthesizing enzyme, as a target of ALK signaling in lung cancer. We demonstrate that ALK binds to and phosphorylates GUK1 at tyrosine 74 (Y74), resulting in increased GDP biosynthesis. Spatial imaging of ALK+ patient tumor specimens shows enhanced phosphorylation of GUK1 that significantly correlates with guanine nucleotides in situ . Abrogation of GUK1 phosphorylation reduces intracellular GDP and guanosine triphosphate (GTP) pools and decreases mitogen-activated protein kinase (MAPK) signaling and Ras-GTP loading. A GUK1 variant that cannot be phosphorylated (Y74F) decreases tumor proliferation in vitro and in vivo . Beyond ALK, other oncogenic fusion proteins in lung cancer also regulate GUK1 phosphorylation. These studies may pave the way for the development of new therapeutic approaches by exploiting metabolic dependencies in oncogene-driven lung cancers.

『摘要』 目前对癌基因驱动的肺癌中的代谢脆弱性知之甚少。本研究对间变性淋巴瘤激酶(ALK)重排(“ALK+”)的患者源性细胞系进行了磷酸化蛋白质组筛选,并确定鸟苷酸激酶1(GUK1)(一种合成鸟苷二磷酸(GDP)的酶)是肺癌中ALK信号传导的靶点。研究证明,ALK与GUK1结合并在酪氨酸74(Y74)位点上使其磷酸化,导致GDP生物合成增加。ALK+患者肿瘤标本的空间成像显示,GUK1的磷酸化增强,与原位鸟嘌呤核苷酸显著相关。抑制GUK1磷酸化可减少细胞内GDP和鸟苷三磷酸(GTP)库,并降低丝裂原活化蛋白激酶(MAPK)信号传导和Ras-GTP加载。一种无法磷酸化的GUK1变体(Y74F)可在体内外降低肿瘤增殖。除ALK外,肺癌中的其他癌性融合蛋白也可调节GUK1的磷酸化。本研究通过利用癌基因驱动肺癌的代谢依赖性,可能为新治疗方法的开发铺平道路。
『总结』 本研究发现GUK1是肺癌中ALK信号传导的靶点,其磷酸化可促进肿瘤增殖,且其他癌性融合蛋白也可调节GUK1磷酸化,这可能为肺癌治疗提供新策略。
【闲叙】

『Abstract』The centromere is the chromosomal locus that recruits the kinetochore, directing faithful propagation of the genome during cell division. Using cryo-ET on human mitotic chromosomes, we reveal a distinctive architecture at the centromere: clustered 20- to 25-nm nucleosome-associated complexes within chromatin clearings that delineate them from surrounding chromatin. Centromere components CENP-C and CENP-N are each required for the integrity of the complexes, while CENP-C is also required to maintain the chromatin clearing. We find that CENP-C is required in mitosis, not just for kinetochore assembly, likely reflecting its role in organizing the inner kinetochore during chromosome segregation. We further visualize the scaffold of the fibrous corona, a structure amplified at unattached kinetochores, revealing crescent-shaped parallel arrays of fibrils extending >1 μm. Thus, we reveal how the organization of centromeric chromatin creates a clearing at the site of kinetochore formation as well as the nature of kinetochore amplification mediated by corona fibrils.

『摘要』 着丝粒是招募动粒的染色体基因座,可在细胞分裂过程中指导基因组的忠实传播。我们利用冷冻电子断层扫描技术对人类有丝分裂染色体进行了研究,揭示了着丝粒的独特结构:染色质间隙内聚集了20至25纳米的核小体相关复合物,这些复合物与周围的染色质有明显的界限。着丝粒组分CENP-C和CENP-N对于复合物的完整性都是必不可少的,而CENP-C对于维持染色质间隙也同样重要。我们发现,在有丝分裂过程中,CENP-C不仅是动粒组装所必需的,很可能还反映了其在染色体分离过程中组织内动粒的作用。我们还进一步观察了纤维冠的支架,这是一种在未结合的动粒处扩增的结构,显示出超过1微米的月牙形平行纤维阵列。因此,我们揭示了着丝粒染色质的组织如何在动粒形成部位产生间隙,以及冠纤维介导的动粒扩增的性质。
『总结』 研究揭示了着丝粒的独特结构及其在动粒形成和扩增中的关键作用,特别是CENP-C和CENP-N对于维持这一结构的重要性。
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『Abstract』Most land plants form symbioses with microbes to acquire nutrients but also must restrict infection by pathogens. Here, we show that a single pair of lysin-motif-containing receptor-like kinases, MpaLYR and MpaCERK1, mediates both immunity and symbiosis in the liverwort Marchantia paleacea . MpaLYR has a higher affinity for long-chain (CO7) versus short-chain chitin oligomers (CO4). Although both CO7 and CO4 can activate symbiosis-related genes, CO7 triggers stronger immune responses than CO4 in a dosage-dependent manner. CO4 can inhibit CO7-induced strong immune responses, recapitulating the early response to inoculation with the symbiont arbuscular mycorrhizal fungi. We show that phosphate starvation of plants increases their production of strigolactone, which stimulates CO4/CO5 secretion from mycorrhizal fungi, thereby prioritizing symbiosis over immunity. Thus, a single pair of LysM receptors mediates dosage-dependent perception of different chitin oligomers to discern symbiotic and pathogenic microbes in M. paleacea , which may facilitate terrestrialization.

『摘要』 大多数陆生植物与微生物形成共生关系以获取营养,但同时也必须限制病原体的感染。本研究发现,在地钱(Marchantia paleacea)中,仅一对含有溶菌酶基序的受体样激酶MpaLYR和MpaCERK1就能介导免疫和共生。相较于短链几丁质低聚物(CO4),MpaLYR对长链几丁质低聚物(CO7)具有更高的亲和力。虽然CO7和CO4都能激活与共生相关的基因,但CO7会以剂量依赖的方式引发比CO4更强烈的免疫反应。CO4能够抑制CO7诱导的强烈免疫反应,这模拟了对丛枝菌根真菌接种的早期反应。研究表明,植物的磷酸盐饥饿会增加其独脚金内酯的产生,这会刺激菌根真菌分泌CO4/CO5,从而优先促进共生而非免疫。因此,在地钱中,仅一对LysM受体就能以剂量依赖的方式感知不同的几丁质低聚物,从而区分共生微生物和病原微生物,这可能促进了植物的陆生化。
『总结』 地钱中的一对LysM受体能够感知不同长度的几丁质低聚物,以剂量依赖的方式介导对共生和病原微生物的识别。
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『Abstract』Industrialization adversely affects the gut microbiome and predisposes individuals to chronic non-communicable diseases. We tested a microbiome restoration strategy comprising a diet that recapitulated key characteristics of non-industrialized dietary patterns (restore diet) and a bacterium rarely found in industrialized microbiomes ( Limosilactobacillus reuteri ) in a randomized controlled feeding trial in healthy Canadian adults. The restore diet, despite reducing gut microbiome diversity, enhanced the persistence of L. reuteri strain from rural Papua New Guinea (PB-W1) and redressed several microbiome features altered by industrialization. The diet also beneficially altered microbiota-derived plasma metabolites implicated in the etiology of chronic non-communicable diseases. Considerable cardiometabolic benefits were observed independently of L. reuteri administration, several of which could be accurately predicted by baseline and diet-responsive microbiome features. The findings suggest that a dietary intervention targeted toward restoring the gut microbiome can improve host-microbiome interactions that likely underpin chronic pathologies, which can guide dietary recommendations and the development of therapeutic and nutritional strategies.

『摘要』 工业化对肠道微生物群产生不利影响,并使个体容易患上慢性非传染性疾病。我们在一项针对健康加拿大成年人的随机对照喂养试验中,测试了一种微生物群恢复策略,该策略包括一种重现非工业化饮食模式关键特征的饮食(恢复饮食)和一种在工业化微生物群中很少发现的细菌(路氏乳杆菌)。恢复饮食虽然降低了肠道微生物群的多样性,但增强了来自巴布亚新几内亚农村的路氏乳杆菌菌株(PB-W1)的持久性,并恢复了工业化改变的一些微生物群特征。该饮食还有益地改变了与慢性非传染性疾病病因相关的微生物群衍生血浆代谢物。在不考虑路氏乳杆菌给药的情况下,也观察到了显著的心血管代谢益处,其中一些益处可以通过基线和饮食反应性微生物群特征准确预测。研究结果表明,针对恢复肠道微生物群的饮食干预可以改善宿主与微生物群的相互作用,这种相互作用可能是慢性病理的基础,从而可以为饮食建议以及治疗和营养策略的制定提供指导。
『总结』 恢复肠道微生物群的饮食干预有助于改善与慢性非传染性疾病相关的宿主-微生物群相互作用。
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『Abstract』A meta-genome-wide association study across eight psychiatric disorders has highlighted the genetic architecture of pleiotropy in major psychiatric disorders. However, mechanisms underlying pleiotropic effects of the associated variants remain to be explored. We conducted a massively parallel reporter assay to decode the regulatory logic of variants with pleiotropic and disorder-specific effects. Pleiotropic variants differ from disorder-specific variants by exhibiting chromatin accessibility that extends across diverse cell types in the neuronal lineage and by altering motifs for transcription factors with higher connectivity in protein-protein interaction networks. We mapped pleiotropic and disorder-specific variants to putative target genes using functional genomics approaches and CRISPR perturbation. In vivo CRISPR perturbation of a pleiotropic and a disorder-specific gene suggests that pleiotropy may involve the regulation of genes expressed broadly across neuronal cell types and with higher network connectivity.

『摘要』 一项跨越八种精神障碍的元全基因组关联研究突显了主要精神障碍中多效性的遗传结构。然而,相关变异体多效性作用的机制仍有待探索。我们进行了一项大规模并行报告基因分析,以破译具有多效性和疾病特异性效应变异体的调控逻辑。多效性变异体与疾病特异性变异体的不同之处在于,它们表现出的神经细胞谱系中多种细胞类型均具有的染色质可及性,并改变了在蛋白质-蛋白质相互作用网络中连接度更高的转录因子的基序。我们使用功能基因组学方法和CRISPR干扰技术将多效性和疾病特异性变异体映射到推定靶基因。对一个多效性基因和一个疾病特异性基因进行体内CRISPR干扰表明,多效性可能涉及在多种神经细胞类型中广泛表达且网络连接度更高的基因的调控。
『总结』 研究发现多效性变异体与疾病特异性变异体具有不同的调控逻辑,多效性可能涉及广泛表达和高网络连接度基因的调控。
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『Abstract』Knowledge of protein-metabolite interactions can enhance mechanistic understanding and chemical probing of biochemical processes, but the discovery of endogenous ligands remains challenging. Here, we combined rapid affinity purification with precision mass spectrometry and high-resolution molecular docking to precisely map the physical associations of 296 chemically diverse small-molecule metabolite ligands with 69 distinct essential enzymes and 45 transcription factors in the gram-negative bacterium Escherichia coli . We then conducted systematic metabolic pathway integration, pan-microbial evolutionary projections, and independent in-depth biophysical characterization experiments to define the functional significance of ligand interfaces. This effort revealed principles governing functional crosstalk on a network level, divergent patterns of binding pocket conservation, and scaffolds for designing selective chemical probes. This structurally resolved ligand interactome mapping pipeline can be scaled to illuminate the native small-molecule networks of complete cells and potentially entire multi-cellular communities.

『摘要』 了解蛋白质-代谢物相互作用可以增强对生化过程机制的理解和化学探针的开发,但内源性配体的发现仍然具有挑战性。本研究将快速亲和纯化技术、精密质谱技术和高分辨率分子对接技术相结合,精确绘制了革兰氏阴性菌大肠杆菌中296种化学性质不同的小分子代谢物配体与69种不同的必需酶和45种转录因子的物理结合图谱。随后,我们进行了系统的代谢途径整合、全微生物进化预测以及独立的深入生物物理表征实验,以明确配体界面的功能意义。这一研究揭示了网络水平上功能串扰的支配原则、结合口袋保守性的不同模式以及设计选择性化学探针的支架。这种结构解析的配体相互作用组绘制流程可扩展应用于揭示完整细胞乃至整个多细胞群落的天然小分子网络。
『总结』 本研究通过综合技术精确绘制了大肠杆菌中小分子代谢物配体与酶及转录因子的物理结合图谱,并揭示了其功能意义和设计化学探针的潜力。
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『Abstract』Current efforts investigating parturition timing mechanisms have focused on the proximal triggers of labor onset generated in late pregnancy. By studying the delayed parturition phenotype of mice with uterine fibroblast deficiencies in the histone H3K27me3 demethylase KDM6B, we provide evidence that parturition timing is regulated by events that take place in early pregnancy. Immediately after copulation, uterine fibroblasts engage in a locus-specific epigenetic program that abruptly adjusts H3K27me3 levels across their genome. In the absence of KDM6B, many of the adjusted loci over-accumulate H3K27me3. This over-accumulation leads to nearby genes being misexpressed in mid-to-late gestation, a delayed effect partly attributable to a second locus-specific but KDM6B-independent process initiated within uterine fibroblasts soon after implantation. This second process employs progressive H3K27me3 loss to temporally structure post-midgestational patterns of gene induction. Further dissection of the ways uterine programming controls parturition timing may have relevance to human pregnancy complications such as preterm labor.

『摘要』 目前,研究分娩时机机制的工作主要集中在妊娠晚期产生的分娩发作的近端触发因素上。通过研究组蛋白H3K27me3去甲基化酶KDM6B缺乏导致子宫成纤维细胞不足的延迟分娩小鼠表型,我们提供了证据,证明分娩时机受到妊娠早期发生的事件的调控。交配后,子宫成纤维细胞立即参与一种位点特异性的表观遗传程序,该程序会在其整个基因组中急剧调整H3K27me3的水平。在缺乏KDM6B的情况下,许多经过调整的位点会过度积累H3K27me3。这种过度积累会导致附近基因在妊娠中后期错误表达,这种延迟效应部分归因于植入后不久在子宫成纤维细胞中启动的第二个位点特异性但独立于KDM6B的过程。第二个过程利用H3K27me3的逐渐丧失来构建妊娠中期后基因诱导的时间模式。进一步剖析子宫编程控制分娩时机的方式可能与早产等人类妊娠并发症相关。
『总结』 研究发现分娩时机受到妊娠早期子宫成纤维细胞表观遗传程序的调控。
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