前沿速递 | NCS 集萃: 2025-05-01 期 [Up]

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『Abstract』Highly pathogenic avian influenza (HPAI) viruses cross species barriers and have the potential to cause pandemics. In North America, HPAI A(H5N1) viruses related to the goose/Guangdong 2.3.4.4b hemagglutinin phylogenetic clade have infected wild birds, poultry, and mammals. Our genomic analysis and epidemiological investigation showed that a reassortment event in wild bird populations preceded a single wild bird–to-cattle transmission episode. The movement of asymptomatic or presymptomatic cattle has likely played a role in the spread of HPAI within the United States dairy herd. Some molecular markers that may lead to changes in transmission efficiency and phenotype were detected at low frequencies. Continued transmission of H5N1 HPAI within dairy cattle increases the risk for infection and subsequent spread of the virus to human populations.

『摘要』 高致病性禽流感(HPAI)病毒可跨越物种屏障,并有可能引发大流行。在北美,与鹅/广东2.3.4.4b血凝素系统发育进化枝相关的高致病性禽流感A(H5N1)病毒已感染野鸟、家禽和哺乳动物。我们的基因组分析和流行病学调查显示,在单次野鸟到牛的传播事件之前,野鸟群体中发生了一次重配事件。无症状或前驱症状牛的流动可能在美国奶牛群中高致病性禽流感的传播中发挥了作用。一些可能导致传播效率和表型发生变化的分子标记以低频被检出。H5N1高致病性禽流感在奶牛中的持续传播增加了病毒向人类感染及随后在人群中传播的风险。
『总结』 北美出现的H5N1高致病性禽流感病毒已跨越物种感染多种动物,且存在向人类传播的风险。
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『Abstract』Since early 2022, highly pathogenic avian influenza (HPAI) H5N1 virus infections have been reported in wild aquatic birds and poultry throughout the USA with spillover into several mammalian species . In March 2024, HPAIV H5N1 clade 2.3.4.4b was first detected in dairy cows in Texas, USA, and continues to circulate on dairy farms in many states . Milk production and quality are diminished in infected dairy cows, with high virus titres in milk raising concerns of exposure to mammals including humans through consumption . Here we investigated routes of infection with bovine HPAIV H5N1 clade 2.3.4.4b in cynomolgus macaques, a surrogate model for human infection . We show that intranasal or intratracheal inoculation of macaques could cause systemic infection resulting in mild and severe respiratory disease, respectively. By contrast, infection by the orogastric route resulted in limited infection and seroconversion of macaques that remained subclinical.

『摘要』 自2022年初以来,美国各地野生水禽和家禽中报告发生了高致病性禽流感(HPAI)H5N1病毒感染,并蔓延至几种哺乳动物。2024年3月,首次在美国德克萨斯州的奶牛中检测到HPAIV H5N1 2.3.4.4b分支病毒,该病毒继续在许多州的奶牛场中传播。受感染的奶牛产奶量下降,奶质降低,且牛奶中病毒滴度高,引发了对包括人类在内的哺乳动物可能通过食用牛奶而暴露于病毒的担忧。本研究在食蟹猴(人类感染的替代模型)中调查了牛源HPAIV H5N1 2.3.4.4b分支病毒的感染途径。研究表明,通过鼻内或气管内接种可使食蟹猴发生全身性感染,分别导致轻度呼吸系统疾病和重度呼吸系统疾病。相比之下,通过口胃途径感染导致的食蟹猴感染程度有限,且血清阳转,但仍处于亚临床状态。
『总结』 美国发现奶牛中H5N1 2.3.4.4b分支病毒感染,研究发现在食蟹猴中鼻内或气管内接种病毒可致严重呼吸系统疾病,而口胃途径感染则较为轻微。
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『Abstract』Lasso peptides (biologically active molecules with a distinct structurally constrained knotted fold) are natural products that belong to the class of ribosomally synthesized and post-translationally modified peptides . Lasso peptides act on several bacterial targets , but none have been reported to inhibit the ribosome, one of the main targets of antibiotics in the bacterial cell . Here we report the identification and characterization of the lasso peptide antibiotic lariocidin and its internally cyclized derivative lariocidin B, produced by Paenibacillus sp. M2, which has broad-spectrum activity against a range of bacterial pathogens. We show that lariocidins inhibit bacterial growth by binding to the ribosome and interfering with protein synthesis. Structural, genetic and biochemical data show that lariocidins bind at a unique site in the small ribosomal subunit, where they interact with the 16S ribosomal RNA and aminoacyl-tRNA, inhibiting translocation and inducing miscoding. Lariocidin is unaffected by common resistance mechanisms, has a low propensity for generating spontaneous resistance, shows no toxicity to human cells, and has potent in vivo activity in a mouse model of Acinetobacter baumannii infection. Our identification of ribosome-targeting lasso peptides uncovers new routes towards the discovery of alternative protein-synthesis inhibitors and offers a novel chemical scaffold for the development of much-needed antibacterial drugs.

『摘要』 Lasso肽(具有独特结构约束的纽结折叠的生物活性分子)是天然产物,属于核糖体合成和翻译后修饰肽类。Lasso肽作用于多种细菌靶点,但目前尚无Lasso肽抑制核糖体的报道,而核糖体是抗生素在细菌细胞中的主要靶点之一。本文报道了由Paenibacillus sp. M2产生的Lasso肽抗生素lariocidin及其内环化衍生物lariocidin B的鉴定和表征,它们对一系列细菌病原体具有广谱活性。研究表明,lariocidins通过与核糖体结合并干扰蛋白质合成来抑制细菌生长。结构、遗传和生化数据表明,lariocidins结合于小核糖体亚基中的一个独特位点,在该位点它们与16S核糖体RNA和氨基酰-tRNA相互作用,抑制易位并诱导错误编码。Lariocidin不受常见耐药机制的影响,产生自发性耐药的倾向较低,对人细胞无毒,并在小鼠鲍曼不动杆菌感染模型中显示出强大的体内活性。本研究发现了靶向核糖体的Lasso肽,为发现替代性蛋白质合成抑制剂开辟了新途径,并为开发迫切需要的抗菌药物提供了一种新型化学支架。
『总结』 本研究鉴定并表征了两种靶向核糖体的Lasso肽抗生素lariocidin和lariocidin B,为抗菌药物的开发提供了新途径和化学支架。
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『Abstract』Structural disorder within materials gives rise to fascinating phenomena, attributed to the intricate interplay of their thermodynamic and electrochemical properties . Oxygen-redox (OR) electrochemistry offers a breakthrough in capacity limits, while inducing structural disorder with reduced electrochemical reversibility . The conventional explanation for the thermal expansion of solids relies on the Gruneisen relationship, linking the expansion coefficient to the anharmonicity of the crystal lattice . However, this paradigm may not be applicable to OR materials due to the unexplored dynamic disorder–order transition in such systems . Here we reveal the presence of negative thermal expansion with a large coefficient value of −14.4(2) × 10 °C in OR active materials, attributing this to thermally driven disorder–order transitions. The modulation of OR behaviour not only enables precise control over the thermal expansion coefficient of materials, but also establishes a pragmatic framework for the design of functional materials with zero thermal expansion. Furthermore, we demonstrate that the reinstatement of structural disorder within the material can also be accomplished through the electrochemical driving force. By adjusting the cut-off voltages, evaluation of the discharge voltage change indicates a potential for nearly 100% structure recovery. This finding offers a pathway for restoring OR active materials to their pristine state through operando electrochemical processes, presenting a new mitigation strategy to address the persistent challenge of voltage decay.

『摘要』 材料内部的结构无序会引发迷人的现象,这归因于其热力学和电化学特性的复杂相互作用。氧氧化还原(OR)电化学突破了容量限制,同时会诱发结构无序并降低电化学可逆性。传统上对固体热膨胀的解释依赖于格林艾森关系,该关系将膨胀系数与晶体晶格的非谐性联系起来。然而,由于氧氧化还原系统中动态无序-有序转变尚未得到探索,这一范式可能并不适用于氧氧化还原材料。在此,我们发现氧氧化还原活性材料中存在负热膨胀现象,其系数值高达−14.4(2) × 10−6 °C−1,并将其归因于热驱动的无序-有序转变。对氧氧化还原行为的调控不仅能够精确控制材料的热膨胀系数,而且为设计零热膨胀功能材料建立了一个实用的框架。此外,我们还证明,通过电化学驱动力也可以恢复材料内部的结构无序。通过调整截止电压,评估放电电压的变化表明结构有可能近乎100%恢复。这一发现为通过原位电化学过程将氧氧化还原活性材料恢复到其原始状态提供了一条途径,为解决电压衰减这一长期存在的挑战提出了一种新的缓解策略。
『总结』 研究发现氧氧化还原活性材料存在负热膨胀现象,通过调控其行为可精确控制材料的热膨胀系数,同时电化学驱动力可恢复材料结构无序,为材料恢复和电压衰减问题提供了新策略。
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『Abstract』Given the high recurrence rates of hepatocellular carcinoma (HCC) post-resection , improved early identification of patients at high risk for post-resection recurrence would help to improve patient outcomes and prioritize healthcare resources . Here we observed a spatial and HCC recurrence-associated distribution of natural killer (NK) cells in the invasive front and tumour centre from 61 patients. Using extreme gradient boosting and inverse-variance weighting, we developed the tumour immune microenvironment spatial (TIMES) score based on the spatial expression patterns of five biomarkers (SPON2, ZFP36L2, ZFP36, VIM and HLA-DRB1) to predict HCC recurrence risk. The TIMES score (hazard ratio = 88.2, P < 0.001) outperformed current standard tools for patient risk stratification including the TNM and BCLC systems. We validated the model in 231 patients from five multicentred cohorts, achieving a real-world accuracy of 82.2% and specificity of 85.7%. The predictive power of these biomarkers emerged through the integration of their spatial distributions, rather than individual marker expression levels alone. In vivo models, including NK cell-specific Spon2 -knockout mice, revealed that SPON2 enhances IFNγ secretion and NK cell infiltration at the invasive front. Our study introduces TIMES, a publicly accessible tool for predicting HCC recurrence risk, offering insights into its potential to inform treatment decisions for early-stage HCC.

『摘要』 鉴于肝细胞癌(HCC)切除术后复发率较高,改进高危复发患者的早期识别方法有助于改善患者预后并优化医疗资源配置。本研究观察了61例患者的侵袭前沿和肿瘤中心的自然杀伤(NK)细胞的空间分布及其与HCC复发的相关性。采用极端梯度提升和逆方差加权方法,我们基于五种生物标志物(SPON2、ZFP36L2、ZFP36、VIM和HLA-DRB1)的空间表达模式,开发了肿瘤免疫微环境空间(TIMES)评分来预测HCC复发风险。TIMES评分(风险比=88.2,P<0.001)在患者风险分层方面优于包括TNM和BCLC系统在内的当前标准工具。我们在来自五个多中心的231例患者中对模型进行了验证,现实世界的准确率达到82.2%,特异性达到85.7%。这些生物标志物的预测能力是通过整合其空间分布而显现的,而非仅依赖单个标志物的表达水平。体内模型(包括NK细胞特异性Spon2敲除小鼠)显示,SPON2可增强侵袭前沿的干扰素γ(IFNγ)分泌和NK细胞浸润。本研究推出了TIMES这一公开可用的预测HCC复发风险的工具,为早期HCC治疗决策提供了新见解。
『总结』 本研究开发并验证了TIMES评分,一种基于五种生物标志物空间表达模式的预测HCC复发风险的新工具,其在患者风险分层方面优于现有标准,并揭示了SPON2在增强NK细胞功能中的作用。
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『Abstract』Stable, nonprecious catalysts are vital for large-scale alkaline water electrolysis. Here, we report a grafted superstructure, MOF@POM, formed by self-assembling a metal-organic framework (MOF) with polyoxometalate (POM). In situ electrochemical transformation converts MOF into active metal (oxy)hydroxides to produce a catalyst with a low overpotential of 178 millivolts at 10 milliamperes per square centimeter in alkaline electrolyte. An anion exchange membrane water electrolyzer incorporating this catalyst achieves 3 amperes per square centimeter at 1.78 volts at 80°C and stable operation at 2 amperes per square centimeter for 5140 hours at room temperature. In situ electrochemical spectroscopy and theoretical studies reveal that the synergistic interactions between metal atoms create a fast electron-transfer channel from catalytic iron and cobalt sites, nickel, and tungsten in the polyoxometalate to the electrode, stabilizing the metal sites and preventing dissolution.

『摘要』 为实现大规模碱性水电解,稳定且非贵金属催化剂至关重要。本文报告了一种接枝的超结构MOF@POM,由金属有机骨架(MOF)与多金属氧酸盐(POM)自组装而成。通过原位电化学转化,MOF转变为活性金属(氧)氢氧化物,从而在碱性电解质中产生了在10毫安每平方厘米下具有178毫伏低过电位的催化剂。使用该催化剂的阴离子交换膜水电解槽在80°C时达到了3安每平方厘米的电流密度,且在1.78伏的电压下工作;在室温、2安每平方厘米的电流密度下,能稳定运行5140小时。原位电化学光谱研究和理论研究表明,金属原子之间的协同作用在催化铁和钴位点、多金属氧酸盐中的镍和钨与电极之间创建了一条快速电子转移通道,从而稳定了金属位点并防止了其溶解。
『总结』 本文报告了一种MOF@POM超结构催化剂,通过原位电化学转化实现了高效稳定的碱性水电解,金属原子间的协同作用促进了快速电子转移并稳定了金属位点。
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『Abstract』Long-range and anisotropic dipolar interactions profoundly modify the dynamics of particles hopping in a periodic lattice potential. We report the realization of a generalized t-J model with dipolar interactions using a system of ultracold fermionic molecules with spin encoded in the two lowest rotational states. We independently tuned the dipolar Ising and spin-exchange couplings and the molecular motion and studied their interplay on coherent spin dynamics. Using Ramsey spectroscopy, we observed and modeled interaction-driven contrast decay that depends strongly both on the strength of the anisotropy between Ising and spin-exchange couplings and on motion. This study paves the way for future exploration of kinetic spin dynamics and quantum magnetism with highly tunable molecular platforms in regimes that are challenging for existing numerical and analytical methods.

『摘要』 长程且各向异性的偶极相互作用极大地改变了粒子在周期性晶格势中跃迁的动力学。我们报告了使用自旋编码在两个最低旋转态中的超冷费米分子系统,实现了具有偶极相互作用的广义t-J模型。我们独立调整了偶极伊辛相互作用和自旋交换耦合以及分子运动,并研究了它们对相干自旋动力学的相互影响。通过拉姆齐光谱学,我们观察并模拟了相互作用驱动的对比度衰减,这种衰减强烈依赖于伊辛相互作用和自旋交换耦合之间各向异性的强度以及运动。本研究为未来利用高度可调的分子平台,在现有数值和解析方法难以解决的领域,探索动力学自旋动力学和量子磁性铺平了道路。
『总结』 本研究通过超冷费米分子系统实现了具有偶极相互作用的广义t-J模型,为探索动力学自旋动力学和量子磁性提供了新途径。
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『Abstract』Four-wave mixing is a nonlinear optical phenomenon that can be used for wideband low-noise optical amplification and wavelength conversion. It has been extensively investigated for applications in communications , computing , metrology , imaging and quantum optics . With its advantages of small footprint, large nonlinearity and dispersion-engineering capability, optical integrated waveguides are excellent candidates for realizing high-gain and large-bandwidth four-wave mixing for which anomalous dispersion is a key condition. Various waveguides based on, for example, silicon, aluminium gallium arsenide and nonlinear glass have been studied , but suffer from considerable gain and bandwidth reductions, as conventional design approaches for anomalous dispersion result in multi-mode operation. We present a methodology for fabricating nonlinear waveguides with simultaneous single-mode operation and anomalous dispersion for ultra-broadband operation and high-efficiency four-wave mixing. Although we implemented this in silicon nitride waveguides, the design approach can be used with other platforms as well. By using higher-order dispersion, we achieved unprecedented amplification bandwidths of more than 300 nm in these ultra-low-loss integrated waveguides. Penalty-free all-optical wavelength conversion of 100 Gbit s data in a single optical channel of over 200 nm was realized. These single-mode dispersion-engineered nonlinear waveguides could become practical building blocks in various nonlinear photonics applications.

『摘要』 四波混频是一种非线性光学现象,可用于宽带低噪声光放大和波长转换。该现象已在通信、计算、计量、成像和量子光学等领域得到了广泛研究。光学集成波导具有体积小、非线性强和色散工程能力强的优点,是实现高增益、大带宽四波混频的绝佳选择,而反常色散是实现这一过程的关键条件。目前,研究者们已研究了基于硅、铝镓砷和非线性玻璃等多种材料的波导,但由于传统的反常色散设计方法会导致多模运行,增益和带宽都会大幅降低。本研究提出了一种制作方法,能制作出同时具有单模运行和反常色散特性的非线性波导,从而实现超宽带运行和高效四波混频。虽然我们是在氮化硅波导中实现的,但这种设计方法也可用于其他平台。通过利用高阶色散,我们在这些超低损耗集成波导中实现了超过300纳米的前所未有的放大带宽。此外,还在超过200纳米的单光信道上实现了100 Gbit/s数据的无惩罚全光波长转换。这些经过色散工程的单模非线性波导有望成为各种非线性光子学应用中的实用构建模块。
『总结』 本研究提出了一种能同时实现单模运行和反常色散的非线性波导制作方法,该方法在氮化硅波导中实现超宽带高效四波混频,为非线性光子学应用提供了新的实用构建模块。
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『Abstract』Mesenchymal plasticity has been extensively described in advanced epithelial cancers; however, its functional role in malignant progression is controversial . The function of epithelial-to-mesenchymal transition (EMT) and cell plasticity in tumour heterogeneity and clonal evolution is poorly understood. Here we clarify the contribution of EMT to malignant progression in pancreatic cancer. We used somatic mosaic genome engineering technologies to trace and ablate malignant mesenchymal lineages along the EMT continuum. The experimental evidence clarifies the essential contribution of mesenchymal lineages to pancreatic cancer evolution. Spatial genomic analysis, single-cell transcriptomic and epigenomic profiling of EMT clarifies its contribution to the emergence of genomic instability, including events of chromothripsis. Genetic ablation of mesenchymal lineages robustly abolished these mutational processes and evolutionary patterns, as confirmed by cross-species analysis of pancreatic and other human solid tumours. Mechanistically, we identified that malignant cells with mesenchymal features display increased chromatin accessibility, particularly in the pericentromeric and centromeric regions, in turn resulting in delayed mitosis and catastrophic cell division. Thus, EMT favours the emergence of genomic-unstable, highly fit tumour cells, which strongly supports the concept of cell-state-restricted patterns of evolution, whereby cancer cell speciation is propagated to progeny within restricted functional compartments. Restraining the evolutionary routes through ablation of clones capable of mesenchymal plasticity, and extinction of the derived lineages, halts the malignant potential of one of the most aggressive forms of human cancer.

『摘要』 间质可塑性在晚期上皮癌中已被广泛描述;然而,其在恶性进展中的功能作用尚存争议。上皮-间质转化(epithelial-to-mesenchymal transition,EMT)和细胞可塑性在肿瘤异质性和克隆进化中的作用尚不清楚。本研究阐明了EMT在胰腺癌恶性进展中的贡献。我们采用体细胞镶嵌基因组工程技术来追踪并清除沿EMT连续体的恶性间质谱系。实验证据阐明了间质谱系对胰腺癌进化的重要贡献。对EMT进行空间基因组分析、单细胞转录组和表观基因组分析,阐明了其对基因组不稳定性(包括染色质碎裂事件)出现的作用。对胰腺癌和其他人类实体瘤进行跨物种分析证实,遗传清除间质谱系可有力消除这些突变过程和进化模式。从机制上讲,我们发现具有间质特征的恶性肿瘤细胞表现出更高的染色质可及性,特别是在近着丝粒和着丝粒区域,这反过来会导致有丝分裂延迟和细胞灾难性分裂。因此,EMT有利于基因组不稳定、高度适应的肿瘤细胞的出现,这一发现有力支持了细胞状态限制性进化模式的概念,即癌细胞特化在限制性功能区内传播给后代。通过清除具有间质可塑性的克隆和消灭衍生谱系来限制进化途径,可阻止这种最具侵袭性的人类癌症之一的恶性潜能。
『总结』 本研究表明间质谱系对胰腺癌进化有重要贡献,且阐明了EMT通过促进基因组不稳定性和高度适应的肿瘤细胞出现,支持了细胞状态限制性进化模式,并指出清除具有间质可塑性的克隆可遏制恶性潜能。
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『Abstract』Tumour cells often evade immune pressure exerted by CD8 T cells or immunotherapies through mechanisms that are largely unclear . Here, using complementary in vivo and in vitro CRISPR–Cas9 genetic screens to target metabolic factors, we established voltage-dependent anion channel 2 (VDAC2) as an immune signal-dependent checkpoint that curtails interferon-γ (IFNγ)-mediated tumour destruction and inflammatory reprogramming of the tumour microenvironment. Targeting VDAC2 in tumour cells enabled IFNγ-induced cell death and cGAS–STING activation, and markedly improved anti-tumour effects and immunotherapeutic responses. Using a genome-scale genetic interaction screen, we identified BAK as the mediator of VDAC2-deficiency-induced effects. Mechanistically, IFNγ stimulation increased BIM, BID and BAK expression, with VDAC2 deficiency eliciting uncontrolled IFNγ-induced BAK activation and mitochondrial damage. Consequently, mitochondrial DNA was aberrantly released into the cytosol and triggered robust activation of cGAS–STING signalling and type I IFN response. Importantly, co-deletion of STING signalling components dampened the therapeutic effects of VDAC2 depletion in tumour cells, suggesting that targeting VDAC2 integrates CD8 T cell- and IFNγ-mediated adaptive immunity with a tumour-intrinsic innate immune-like response. Together, our findings reveal VDAC2 as a dual-action target to overcome tumour immune evasion and establish the importance of coordinately destructing and inflaming tumours to enable efficacious cancer immunotherapy.

『摘要』 肿瘤细胞经常通过一些尚不完全清楚的机制逃避CD8 T细胞或免疫疗法施加的免疫压力。本研究利用互补的体内和体外CRISPR–Cas9基因筛选技术针对代谢因素,确定电压依赖性阴离子通道2(VDAC2)是一个免疫信号依赖性检查点,可抑制干扰素-γ(IFNγ)介导的肿瘤破坏和肿瘤微环境的炎症重编程。在肿瘤细胞中靶向VDAC2可诱导IFNγ介导的细胞死亡和cGAS–STING活化,并显著改善抗肿瘤作用和免疫治疗效果。通过基因组规模的遗传相互作用筛选,本研究确定了BAK是VDAC2缺失诱导效应的介导因子。在机制上,IFNγ刺激增加了BIM、BID和BAK的表达,而VDAC2缺失则引起IFNγ诱导的BAK活化和线粒体损伤失控。因此,线粒体DNA异常释放到细胞质中,并触发cGAS–STING信号传导和I型IFN反应的强烈活化。重要的是,共同缺失STING信号传导组分会减弱肿瘤细胞中VDAC2耗竭的治疗效果,这表明靶向VDAC2可将CD8 T细胞和IFNγ介导的适应性免疫与肿瘤内在的先天免疫样反应结合起来。综上所述,本研究发现VDAC2是克服肿瘤免疫逃避的双重作用靶点,并阐明了协调破坏和炎症肿瘤对于实现有效癌症免疫治疗的重要性。
『总结』 本研究揭示了VDAC2在肿瘤免疫逃避中的作用,并证明靶向VDAC2可结合适应性免疫和肿瘤内在免疫反应,提高癌症免疫治疗的效果。
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『Abstract』Social grouping increases survival in many species, including humans . By contrast, social isolation generates an aversive state (‘loneliness’) that motivates social seeking and heightens social interaction upon reunion . The observed rebound in social interaction triggered by isolation suggests a homeostatic process underlying the control of social need, similar to physiological drives such as hunger, thirst or sleep . In this study, we assessed social responses in several mouse strains, among which FVB/NJ mice emerged as highly, and C57BL/6J mice as moderately, sensitive to social isolation. Using both strains, we uncovered two previously uncharacterized neuronal populations in the hypothalamic preoptic nucleus that are activated during either social isolation or social rebound and orchestrate the behaviour display of social need and social satiety, respectively. We identified direct connectivity between these two populations and with brain areas associated with social behaviour, emotional state, reward and physiological needs and showed that mice require touch to assess the presence of others and fulfil their social need. These data show a brain-wide neural system underlying social homeostasis and provide significant mechanistic insights into the nature and function of circuits controlling instinctive social need and for the understanding of healthy and diseased brain states associated with social context.

『摘要』 许多物种(包括人类)通过群体生活来提高生存几率。相比之下,社会孤立会产生一种厌恶状态(“孤独感”),这种状态会促使个体寻求社交,并在重新团聚时加强社交互动。观察到的由孤立引发的社交互动反弹表明,社交需求的控制背后存在一种与饥饿、口渴或睡眠等生理驱动力相似的稳态过程。在本研究中,我们评估了几种小鼠品系的社交反应,其中FVB/NJ小鼠对社交孤立的敏感度较高,而C57BL/6J小鼠的敏感度适中。利用这两种品系的小鼠,我们发现了下丘脑视前核中两个以前未被表征的神经元群体,它们在社交孤立或社交反弹期间被激活,并分别协调社交需求和社交满足的行为表现。我们确定了这两个神经元群体之间的直接连接,以及与社交行为、情绪状态、奖励和生理需求相关脑区的连接,并表明小鼠需要通过触觉来评估其他个体的存在并满足其社交需求。这些数据揭示了一个控制社交稳态的全脑神经系统,并为理解控制本能社交需求的神经回路的性质和功能,以及理解与健康和疾病相关的社交情境下的大脑状态提供了重要的机制见解。
『总结』 研究发现下丘脑视前核中的两个神经元群体在社交孤立或反弹期间被激活,揭示了控制社交稳态的全脑神经系统,为理解社交需求的神经机制提供了新见解。
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『Abstract』The electric double layer (EDL) is critical in electrochemical capacitors and transistors, on-water chemistry, and bioelectric technologies. Ion dynamics within the EDL define the limits for charging and discharging processes. Classical EDL models struggle at high electrolyte concentrations, and observing EDL dynamics has been challenging. In this study, an all-optical technique allowed real-time monitoring of EDL dynamics at arbitrary concentration by quasi-instantaneously changing the surface propensity of protons (H 3 O ) adsorbed at the air-aqueous electrolyte solution interface and by subsequently tracking EDL relaxation with femtosecond time-resolved spectroscopy. EDL reorganization occurred on picosecond timescales and was strongly concentration dependent. Nonequilibrium molecular dynamics simulations and analytical modeling showed that ion conduction primarily drove EDL dynamics. This research quantified EDL dynamics and identified its primary driver, providing insights for optimization of electrochemical applications.

『摘要』 电双层(EDL)在电化学电容器和晶体管、水面化学以及生物电技术中至关重要。电双层内的离子动力学决定了充电和放电过程的极限。传统的电双层模型在高电解质浓度下存在局限,且观测电双层的动力学一直具有挑战性。在这项研究中,一种全光学技术通过准瞬时改变吸附在空气-水基电解质溶液界面的质子(H3O+)的表面倾向,并随后用飞秒时间分辨光谱追踪电双层的松弛过程,从而实现了对任意浓度下电双层动力学的实时监测。电双层的重组发生在皮秒时间尺度上,并且强烈依赖于浓度。非平衡分子动力学模拟和分析建模表明,离子传导是驱动电双层动力学的主要因素。这项研究量化了电双层动力学并确定了其主要驱动力,为优化电化学应用提供了见解。
『总结』 该研究通过全光学技术实时监测了任意浓度下的电双层动力学,并发现离子传导是其主要驱动力,为电化学应用的优化提供了新见解。
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『Abstract』The Saharo-Arabian Desert is one of the largest biogeographical barriers on Earth, impeding dispersals between Africa and Eurasia, including movements of past hominins. Recent research suggests that this barrier has been in place since at least 11 million years ago . In contrast, fossil evidence from the late Miocene epoch and the Pleistocene epoch suggests the episodic presence within the Saharo-Arabian Desert interior of water-dependent fauna (for example, crocodiles, equids, hippopotamids and proboscideans) , sustained by rivers and lakes that are largely absent from today’s arid landscape. Although numerous humid phases occurred in southern Arabia during the past 1.1 million years , little is known about Arabia’s palaeoclimate before this time. Here, based on a climatic record from desert speleothems, we show recurrent humid intervals in the central Arabian interior over the past 8 million years. Precipitation during humid intervals decreased and became more variable over time, as the monsoon’s influence weakened, coinciding with enhanced Northern Hemisphere polar ice cover during the Pleistocene. Wetter conditions likely facilitated mammalian dispersals between Africa and Eurasia, with Arabia acting as a key crossroads for continental-scale biogeographic exchanges.

『摘要』 撒哈拉-阿拉伯沙漠是地球上最大的生物地理屏障之一,阻碍了非洲与欧亚大陆之间的物种迁移,包括古代人类的迁徙。近期研究表明,这一屏障至少在1100万年前就已形成。相比之下,来自中新世晚期和更新世的化石证据表明,撒哈拉-阿拉伯沙漠腹地曾间歇性存在依赖水源的动物群(例如鳄鱼、马类、河马类和长鼻类),这些动物依赖当时丰富的河流和湖泊生存,而这些水体在当今干旱的景观中已大多消失。尽管在过去110万年间,阿拉伯南部曾多次出现湿润期,但在此之前阿拉伯地区的古气候状况却鲜为人知。本研究基于沙漠洞穴石笋的气候记录,揭示了阿拉伯内陆中部在过去800万年里反复出现的湿润期。随着季风影响的减弱,湿润期的降水量随时间推移而减少且变得更加多变,这与更新世期间北半球极地冰盖扩张的现象相吻合。更为湿润的气候条件可能促进了非洲与欧亚大陆之间的哺乳动物迁徙,使阿拉伯地区成为大陆尺度生物地理交流的关键枢纽。
『总结』 新研究表明撒哈拉-阿拉伯沙漠腹地800万年来存在反复湿润期,可能促进了非洲与欧亚大陆的哺乳动物迁徙。
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『Abstract』Gliomas are incurable malignancies notable for having an immunosuppressive microenvironment with abundant myeloid cells, the immunomodulatory phenotypes of which remain poorly defined . Here we systematically investigate these phenotypes by integrating single-cell RNA sequencing, chromatin accessibility, spatial transcriptomics and glioma organoid explant systems. We discovered four immunomodulatory expression programs: microglial inflammatory and scavenger immunosuppressive programs, which are both unique to primary brain tumours, and systemic inflammatory and complement immunosuppressive programs, which are also expressed by non-brain tumours. The programs are not contingent on myeloid cell type, developmental origin or tumour mutational state, but instead are driven by microenvironmental cues, including tumour hypoxia, interleukin-1β, TGFβ and standard-of-care dexamethasone treatment. Their relative expression can predict immunotherapy response and overall survival. By associating the respective programs with mediating genomic elements, transcription factors and signalling pathways, we uncover strategies for manipulating myeloid-cell phenotypes. Our study provides a framework to understand immunomodulation by myeloid cells in glioma and a foundation for the development of more-effective immunotherapies.

『摘要』 胶质瘤是一种无法治愈的恶性肿瘤,其显著特征是具有丰富的髓系细胞和免疫抑制性微环境,但髓系细胞的免疫调节表型尚未明确。本研究通过整合单细胞RNA测序、染色质可及性、空间转录组学和胶质瘤类器官移植系统,系统地研究了这些表型。我们发现了四种免疫调节表达程序:小胶质细胞炎性程序和吞噬细胞免疫抑制程序,这两者都是原发性脑肿瘤特有的;以及系统性炎性程序和补体免疫抑制程序,这两者在非脑肿瘤中也有表达。这些程序的表达不依赖于髓系细胞类型、发育起源或肿瘤的突变状态,而是由微环境信号驱动,包括肿瘤缺氧、白介素-1β、转化生长因子β和标准治疗的地塞米松给药。这些程序的相对表达可以预测免疫治疗的反应和总生存期。通过将各自的程序与介导的基因组元件、转录因子和信号通路相关联,我们发现了调控髓系细胞表型的策略。本研究为理解髓系细胞在胶质瘤中的免疫调节作用提供了一个框架,也为开发更有效的免疫治疗方法奠定了基础。
『总结』 本研究通过多组学方法揭示了胶质瘤中髓系细胞的四种免疫调节表达程序及其驱动因素,为胶质瘤的免疫治疗提供了新的策略和基础。
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『Abstract』Materials with a high electrocaloric effect (ECE) tend to favour a disordered yet easily tunable polar structure. Perovskite ferroelectrics stand out as ideal candidates owing to their high dielectric responses and reasonable thermal conductivity. The introduction of multielement atomic distortions induces a high-polar-entropy state that notably increases the ECE by effectively overcoming the constraints imposed by highly ordered, polar-correlated perovskite structures. Here we developed a lead-free relaxor ferroelectric with strong polar disorder through targeted multielement substitution at both the A and B sites of the perovskite, effectively distorting the lattice structure and inducing a variety of nanoscale polar configurations, polymorphic polar variants and non-polar regions. A combination of these multielement-induced features led to an increased density of interfaces, significantly enhancing the polar entropy. Remarkably, a high ECE for an entropy change of about 15 J kg K under a 10 MV m field is observed for the material across a broad temperature range exceeding 60 °C. The formation of ultrafine, dispersed, multiphase lattice configurations leads to high-polar-entropy ferroelectric oxides with a high ECE and a long lifetime of over 1 million cycles that are suitable for manufacturing multilayer ceramic capacitors for practical electrocaloric refrigeration applications.

『摘要』 具有高电热效应(ECE)的材料往往倾向于具有无序但易于调整的极性结构。钙钛矿型铁电体因其高介电响应和合理的热导率而成为理想的候选材料。引入多元素原子畸变会诱导产生一种高极性熵态,通过有效克服高度有序、极性相关的钙钛矿结构的限制,显著提高了电热效应。本研究通过有针对性地在钙钛矿的A位和B位进行多元素取代,开发了一种具有强极性无序性的无铅弛豫铁电体,有效地扭曲了晶格结构,并诱导产生了多种纳米级极性构型、多态极性变体和非极性区域。这些由多元素诱导产生的特征相结合,提高了界面密度,从而显著增强了极性熵。值得注意的是,在10 MV/m的电场下,该材料在超过60°C的宽温度范围内观察到了约15 J/kg·K的熵变,表现出高热电效应。超细、分散、多相晶格构型的形成导致了具有高电热效应和超过100万次循环长寿命的高极性熵铁电氧化物的产生,适用于制造多层陶瓷电容器,以应用于实际的电热制冷。
『总结』 研究通过多元素取代开发了一种无铅弛豫铁电体,该铁电体具有高极性熵和高电热效应,且循环寿命长,适用于电热制冷应用中的多层陶瓷电容器制造。
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『Abstract』The tumour-suppressor protein BRCA2 has a central role in homology-directed DNA repair by enhancing the formation of RAD51 filaments on resected single-stranded DNA generated at double-stranded DNA breaks and stimulating RAD51 activity . Individuals with BRCA2 mutations are predisposed to cancer; however, BRCA2-deficient tumours are often responsive to targeted therapy with PARP inhibitors (PARPi) . The mechanism by which BRCA2 deficiency renders cells sensitive to PARPi but with minimal toxicity in cells heterozygous for BRCA2 mutations remains unclear. Here we identify a previously unknown role of BRCA2 that is directly linked to the effect of PARP1 inhibition. Using biochemical and single-molecule approaches, we demonstrate that PARPi-mediated PARP1 retention on a resected DNA substrate interferes with RAD51 filament stability and impairs RAD51-mediated DNA strand exchange. Full-length BRCA2 protects RAD51 filaments and counteracts the instability conferred by PARPi-mediated retention by preventing the binding of PARP1 to DNA. Extending these findings to a cellular context, we use quantitative single-molecule localization microscopy to show that BRCA2 prevents PARPi-induced PARP1 retention at homologous-recombination repair sites. By contrast, BRCA2-deficient cells exhibit increased PARP1 retention at these lesions in response to PARPi. These results provide mechanistic insights into the role of BRCA2 in maintaining RAD51 stability and protecting homologous-recombination repair sites by mitigating PARPi-mediated PARP1 retention.

『摘要』 肿瘤抑制蛋白BRCA2在同源导向的DNA修复中起着核心作用,它能促进在双链DNA断裂处产生的单链DNA上RAD51细丝的形成,并刺激RAD51的活性。携带BRCA2突变的人易患癌症;然而,BRCA2缺陷型肿瘤通常对PARP抑制剂(PARPi)的靶向治疗有反应。BRCA2缺失使细胞对PARPi敏感,但在BRCA2杂合突变细胞中却几乎无毒,其作用机制尚不清楚。在这里,我们发现了BRCA2的一个先前未知的作用,该作用与PARP1抑制的效应直接相关。利用生物化学和单分子方法,我们证明,PARPi介导的PARP1在切除的DNA底物上的滞留会干扰RAD51细丝的稳定性,并损害RAD51介导的DNA链交换。全长的BRCA2能保护RAD51细丝,并通过阻止PARP1与DNA的结合来抵消PARPi介导的滞留所引起的不稳定性。将这些研究结果扩展到细胞层面,我们使用定量单分子定位显微镜证明,BRCA2能防止PARPi诱导的PARP1在同源重组修复位点的滞留。相比之下,BRCA2缺陷型细胞在PARPi的作用下,在这些损伤部位表现出增加的PARP1滞留。这些结果为BRCA2通过减轻PARPi介导的PARP1滞留来维持RAD51的稳定性和保护同源重组修复位点的作用提供了机制上的见解。
『总结』 研究发现BRCA2可防止PARPi诱导的PARP1在同源重组修复位点的滞留,从而维持RAD51稳定性和保护修复位点,为理解BRCA2在DNA修复中的作用提供了新机制。
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『Abstract』Long interspersed element–1 (LINE-1) retrotransposons are the only active autonomous transposable elements in humans. They propagate by reverse transcribing their messenger RNA into new genomic locations by a process called target-primed reverse transcription (TPRT). In this work, we present four cryo–electron microscopy structures of the human LINE-1 TPRT complex, revealing the conformational dynamics of open reading frame 2 protein (ORF2p) and its extensive remodeling of the target DNA for TPRT initiation. We observe nicking of the DNA second strand during reverse transcription of the first strand. Structure prediction identifies high-confidence binding sites for LINE-1–associated factors—namely proliferating cell nuclear antigen (PCNA) and cytoplasmic poly(A)-binding protein 1 (PABPC1)—on ORF2p. Together with our structural data, this suggests a mechanism by which these factors regulate retrotransposition and supports a model for TPRT that accounts for retrotransposition outcomes observed in cells.

『摘要』 长散在元件-1(LINE-1)逆转录转座子是人体内唯一活跃的自主转座元件。它们通过一种称为靶引物逆转录(TPRT)的过程,将其信使RNA逆转录到新的基因组位点从而进行传播。在本研究中,我们展示了人类LINE-1 TPRT复合物的四种冷冻电子显微镜结构,揭示了开放阅读框2蛋白(ORF2p)的构象动态及其为启动TPRT对靶DNA进行的大量重塑。我们观察到在第一条链逆转录期间,DNA的第二条链发生了缺口切割。结构预测在ORF2p上确定了LINE-1相关因子(即增殖细胞核抗原(PCNA)和细胞质多聚(A)结合蛋白1(PABPC1))的高置信度结合位点。结合我们的结构数据,这表明了一种机制,通过这些机制,这些因子可以调节逆转录转座,并为TPRT模型提供了支持,该模型解释了细胞中观察到的逆转录转座结果。
『总结』 本研究揭示了人类LINE-1 TPRT复合物的结构,阐明了其关键蛋白的动态构象及相关因子调节逆转录转座的机制。
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『Abstract』Signaling from pathogen sensing to effector activation is a fundamental principle of cellular immunity. Whereas cyclic (oligo)nucleotides have emerged as key signaling molecules, the existence of other messengers remains largely unexplored. In this study, we reveal a bacterial antiphage system that mediates immune signaling through nucleobase modification. Immunity is triggered by phage nucleotide kinases, which, combined with the system-encoded adenosine deaminase, produce deoxyinosine triphosphates (dITPs) as immune messengers. The dITP signal activates a downstream effector to mediate depletion of cellular nicotinamide adenine dinucleotide (oxidized form), resulting in population-level defense through the death of infected cells. To counteract immune signaling, phages deploy specialized enzymes that deplete cellular deoxyadenosine monophosphate, the precursor of dITP messengers. Our findings uncover a nucleobase modification–based antiphage signaling pathway, establishing noncanonical nucleotides as a new type of immune messengers in bacteria.

『摘要』 细胞免疫的一个基本原理是从病原体感知到效应物活化的信号传导。虽然环状(寡)核苷酸已成为关键的信号分子,但其他信使分子的存在在很大程度上仍未被发掘。在本研究中,我们揭示了一种通过碱基修饰介导免疫信号传导的细菌抗噬菌体系统。该系统由噬菌体核苷酸激酶触发免疫,该系统与编码的腺苷脱氨酶结合,产生脱氧肌苷三磷酸(dITP)作为免疫信使。dITP信号激活下游效应物,导致细胞烟酰胺腺嘌呤二核苷酸(氧化态)耗竭,从而通过感染细胞死亡实现群体水平的防御。为了抵消免疫信号,噬菌体会释放特定的酶来耗竭细胞脱氧腺苷单磷酸(dITP信使的前体)。我们的研究结果揭示了一条基于碱基修饰的抗噬菌体信号通路,将非常规核苷酸确立为细菌中一种新型的免疫信使。
『总结』 本研究发现了一种细菌通过碱基修饰介导抗噬菌体免疫信号的新机制,其中脱氧肌苷三磷酸作为新型免疫信使发挥作用。
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『Abstract』Zeolites have exceptional catalytic performance in oil refining and chemical synthesis that can be attributed to their well-defined porous structures that host active sites. This study pinpoints the exact locations of aluminum atoms in ZSM-5 structures—a key zeolite catalyst. Aluminum siting governs catalytic efficiency in acid and redox processes. Anomalous x-ray powder diffraction (AXRPD) at the aluminum K-edge probes the long-range order of aluminum atoms within the ZSM-5 frameworks, precisely quantifying both isolated aluminum atoms and Al(-O-Si-O-) x Al sequences (aluminum pairs). Supported by nuclear magnetic resonance studies, AXRPD unambiguously determines the crystallographic organization of aluminum pairs, recognized spectroscopically as α, β, and γ sites, linking their distribution to superior catalytic activity in propene oligomerization. This combined approach provides essential insights for optimizing zeolite catalysts and enhancing their performance.

『摘要』 沸石在石油炼制和化学合成中具有卓越的催化性能,这归因于其具有明确多孔结构,这些多孔结构承载着活性位点。本研究精确确定了ZSM-5结构(一种关键沸石催化剂)中铝原子的具体位置。铝的位点决定了酸和氧化还原过程中的催化效率。铝K边的异常X射线粉末衍射(AXRPD)探测了ZSM-5骨架中铝原子的长程有序性,准确量化了孤立的铝原子和Al(-O-Si-O-)xAl序列(铝对)。在核磁共振研究的支持下,AXRPD明确确定了铝对的晶体学组织,这些铝对在光谱上被识别为α、β和γ位点,并将其分布与丙烯低聚反应中优越的催化活性联系起来。这种综合方法为优化沸石催化剂和提高其性能提供了重要见解。
『总结』 本研究通过精确确定ZSM-5沸石中铝原子的位置,为优化沸石催化剂和提高其催化性能提供了关键见解。
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『Abstract』Recent advances in quantum communications have underscored the crucial role of optical coherence in developing quantum networks. This resource, which is fundamental to the phase-based architecture of the quantum internet , has enabled the only successful demonstrations of multi-node quantum networks and substantially extended the range of quantum key distribution (QKD) . However, the scalability of coherence-based quantum protocols remains uncertain owing to the specialized hardware required, such as ultra-stable optical cavities and cryogenic photon detectors. Here we implement the coherence-based twin-field QKD protocol over a 254-kilometre commercial telecom network spanning between Frankfurt and Kehl, Germany, achieving encryption key distribution at 110 bits per second. Our results are enabled by a scalable approach to optical coherence distribution, supported by a practical system architecture and non-cryogenic single-photon detection aided by off-band phase stabilization. Our results demonstrate repeater-like quantum communication in an operational network setting, doubling the distance for practical real-world QKD implementations without cryogenic cooling. In addition, to our knowledge, we realized one of the largest QKD networks featuring measurement-device-independent properties . Our research aligns the requirements of coherence-based quantum communication with the capabilities of existing telecommunication infrastructure, which is likely to be useful to the future of high-performance quantum networks, including the implementation of advanced quantum communication protocols, quantum repeaters, quantum sensing networks and distributed quantum computing .

『摘要』 最近的量子通信进展凸显了光相干性在开发量子网络中的关键作用。这一资源对基于相位的量子互联网架构至关重要,它已成功实现了唯一的多节点量子网络演示,并显著扩展了量子密钥分发(QKD)的范围。然而,由于需要超稳定光学腔和低温光子探测器等特殊硬件,基于相干性的量子协议的可扩展性仍然不确定。在此,我们在德国法兰克福和克尔之间跨越254公里的商用电信网络上实现了基于相干性的双场QKD协议,实现了每秒110比特的加密密钥分发。我们的成果得益于一种可扩展的光相干分布方法,该方法得到了实用的系统架构和借助非带内相位稳定的非低温单光子检测的支持。我们的结果展示了在实际网络环境中类似中继器的量子通信,无需低温冷却即可将实际QKD实现的距离加倍。此外,据我们所知,我们实现了具备测量设备无关特性的最大QKD网络之一。我们的研究使基于相干性的量子通信要求与现有电信基础设施的能力相协调,这可能对未来高性能量子网络的发展(包括先进量子通信协议、量子中继器、量子传感网络和分布式量子计算的实施)有所助益。
『总结』 研究团队在德国商用电信网络上实现了基于相干性的双场QKD协议,提升了量子通信的距离和速率,同时使基于相干性的量子通信与现有电信基础设施相协调,有助于未来高性能量子网络的发展。
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『Abstract』Radio-frequency (RF) accelerators providing high-quality relativistic electron beams are an important resource enabling many areas of science, as well as industrial and medical applications. Two decades ago, laser-plasma accelerators that support orders of magnitude higher electric fields than those provided by modern RF cavities produced quasi-monoenergetic electron beams for the first time . Since then, high-brightness electron beams at gigaelectronvolt (GeV) beam energy and competitive beam properties have been demonstrated from only centimetre-long plasmas , a substantial advantage over the hundreds of metres required by RF-cavity-based accelerators. However, despite the considerable progress, the comparably large energy spread and the fluctuation (jitter) in beam energy still effectively prevent laser-plasma accelerators from driving real-world applications. Here we report the generation of a laser-plasma electron beam using active energy compression, resulting in a performance so far only associated with modern RF-based accelerators. Using a magnetic chicane, the electron bunch is first stretched longitudinally to imprint an energy correlation, which is then removed with an active RF cavity. The resulting energy spread and energy jitter are reduced by more than an order of magnitude to below the permille level, meeting the acceptance criteria of a modern synchrotron, thereby opening the path to a compact storage ring injector and other applications.

『摘要』 射频(RF)加速器能提供高质量的相对论电子束,是众多科学领域以及工业和医学应用的重要资源。二十年前,激光等离子体加速器产生了首批准单能电子束,其支持的电场强度比现代射频腔提供的电场高出数个量级。从那时起,仅有数厘米长的等离子体就能产生具有吉电子伏特(GeV)束能量和优良束流特性的高亮度电子束,这相较于基于射频腔的加速器所需的数百米长度具有显著优势。然而,尽管取得了相当大的进展,但相对较大的能散和束流能量波动(抖动)仍然严重阻碍了激光等离子体加速器在实际应用中的推广。本文报告了一种利用主动能量压缩技术产生激光等离子体电子束的方法,该方法所获得的性能迄今为止仅与现代基于射频的加速器相当。通过使用磁偏转器,首先使电子束在纵向上拉长以形成能量相关性,然后利用主动射频腔消除这种相关性。由此,能散和能量抖动降低了一个量级以上,至千分之一以下,达到了现代同步加速器的接收标准,从而为紧凑型储存环注入器和其他应用开辟了道路。
『总结』 研究人员利用主动能量压缩技术成功生成了激光等离子体电子束,其性能与现代基于射频的加速器相当,降低了能散和能量抖动,为激光等离子体加速器的实际应用开辟了新的可能。
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『Abstract』Mutation of some genes drives uncontrolled cell proliferation and cancer. The Philadelphia chromosome in chronic myeloid leukaemia (CML) provided the very first such genetic link to cancer . However, little is known about the trajectory to CML, the rate of BCR::ABL1 clonal expansion and how this affects disease. Using whole-genome sequencing of 1,013 haematopoietic colonies from nine patients with CML aged 22 to 81 years, we reconstruct phylogenetic trees of haematopoiesis. Intronic breaks in BCR and ABL1 were not always observed, and out-of-frame exonic breakpoints in BCR , requiring exon skipping to derive BCR::ABL1 , were also noted. Apart from ASXL1 and RUNX1 mutations, extra myeloid gene mutations were mostly present in wild-type cells. We inferred explosive growth attributed to BCR::ABL1 commencing 3–14 years (confidence interval 2–16 years) before diagnosis, with annual growth rates exceeding 70,000% per year. Mutation accumulation was higher in BCR::ABL1 cells with shorter telomere lengths, reflecting their excessive cell divisions. Clonal expansion rates inversely correlated with the time to diagnosis. BCR::ABL1 in the general population mirrored CML incidence, and advanced and/or blast phase CML was characterized by subsequent genomic evolution. These data highlight the oncogenic potency of BCR::ABL1 fusion and contrast with the slow and sequential clonal trajectories of most cancers.

『摘要』 某些基因的突变会导致细胞失控增殖和癌症的发生。慢性髓系白血病(CML)中的费城染色体是最早发现的与癌症相关的遗传变异。然而,关于CML的发展轨迹、BCR::ABL1克隆扩增的速度以及这对疾病的影响,人们知之甚少。本研究对9名年龄22至81岁的CML患者的1013个造血细胞群进行了全基因组测序,重建了造血的系统发育树。并非总是能观察到BCR和ABL1的内含子断裂,同时还注意到BCR中存在需要外显子跳跃才能推导出BCR::ABL1的框外外显子断裂点。除ASXL1和RUNX1突变外,额外的髓系基因突变大多出现在野生型细胞中。研究人员推断,BCR::ABL1导致的爆发性生长始于诊断前3至14年(置信区间为2至16年),年增长率超过70000%。端粒长度较短的BCR::ABL1细胞中突变累积更多,这反映了其过度的细胞分裂。克隆扩增速率与诊断时间呈负相关。一般人群中的BCR::ABL1融合基因与CML的发生率相符,且进展期和/或急变期CML的特征是随后的基因组进化。这些数据凸显了BCR::ABL1融合的致癌潜力,并与大多数癌症缓慢且顺序性的克隆发展轨迹形成了对比。
『总结』 本研究通过全基因组测序揭示了BCR::ABL1融合基因在CML中的致癌作用及其克隆扩增特点,与多数癌症的克隆发展模式截然不同。
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『Abstract』The phytohormone auxin (Aux) is a principal endogenous developmental signal in plants. It mediates transcriptional reprogramming by a well-established canonical signalling mechanism. TIR1/AFB auxin receptors are F-box subunits of an ubiquitin ligase complex; after auxin perception, they associate with Aux/IAA transcriptional repressors and ubiquitinate them for degradation, thus enabling the activation of auxin response factor (ARF) transcription factors . Here we revise this paradigm by showing that without TIR1 adenylate cyclase (AC) activity , auxin-induced degradation of Aux/IAAs is not sufficient to mediate the transcriptional auxin response. Abolishing the TIR1 AC activity does not affect auxin-induced degradation of Aux/IAAs but renders TIR1 non-functional in mediating transcriptional reprogramming and auxin-regulated development, including shoot, root, root hair growth and lateral root formation. Transgenic plants show that local cAMP production in the vicinity of the Aux/IAA–ARF complex by unrelated AC enzymes bypasses the need for auxin perception and is sufficient to induce ARF-mediated transcription. These discoveries revise the canonical model of auxin signalling and establish TIR1/AFB-produced cAMP as a second messenger essential for transcriptional reprograming.

『摘要』 植物激素生长素(Aux)是植物体内主要的内源发育信号。它通过一种公认的经典信号机制介导转录重编程。TIR1/AFB生长素受体是泛素连接酶复合体的F-box亚基;感知生长素后,它们会与Aux/IAA转录阻遏物结合,并使其泛素化以进行降解,从而激活生长素响应因子(ARF)转录因子。本研究通过证明在没有TIR1腺苷酸环化酶(AC)活性的情况下,生长素诱导的Aux/IAA降解不足以介导转录生长素反应,从而修正了这一范式。消除TIR1 AC活性不会影响生长素诱导的Aux/IAA降解,但会使TIR1在介导转录重编程和生长素调节的发育(包括茎、根、根毛的生长和侧根的形成)方面失去功能。转基因植物的研究表明,无关AC酶在Aux/IAA–ARF复合物附近局部产生的cAMP可以绕过生长素感知的需要,足以诱导ARF介导的转录。这些发现修正了生长素信号转导的经典模型,并确定TIR1/AFB产生的cAMP是转录重编程所必需的第二信使。
『总结』 研究发现TIR1/AFB的腺苷酸环化酶活性对生长素信号转导至关重要,产生的cAMP作为第二信使参与转录重编程。
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『Abstract』Metamaterials with multimodal deformation mechanisms resemble machines , especially when endowed with autonomous functionality. A representative architected assembly, with tunable chirality, converts linear motion into rotation . These chiral metamaterials with a machine-like dual modality have potential use in areas such as wave manipulation , optical activity related to circular polarization and chiral active fluids . However, the dual motions are essentially coupled and cannot be independently controlled. Moreover, they are restricted to small deformation, that is, strain ≤2%, which limits their applications. Here we establish modular chiral metamaterials, consisting of auxetic planar tessellations and origami-inspired columnar arrays, with decoupled actuation. Under single-degree-of-freedom actuation, the assembly twists between 0° and 90°, contracts in-plane up to 25% and shrinks out-of-plane more than 50%. Using experiments and simulations, we show that the deformation of the assembly involves in-plane twist and contraction dominated by the rotating-square tessellations and out-of-plane shrinkage dominated by the tubular Kresling origami arrays. Moreover, we demonstrate two distinct actuation conditions: twist with free translation and linear displacement with free rotation. Our metamaterial is built on a highly modular assembly, which enables reprogrammable instability, local chirality control, tunable loading capacity and scalability. Our concept provides routes towards multimodal, multistable and reprogrammable machines, with applications in robotic transformers, thermoregulation, mechanical memories in hysteresis loops, non-commutative state transition and plug-and-play functional assemblies for energy absorption and information encryption.

『摘要』 具有多模态变形机制的超材料类似于机器,尤其是在被赋予自主功能时更是如此。一种具有可调手性的代表性结构组件能将直线运动转化为旋转运动。这些具有机器般双模态特性的手性超材料在波操控、与圆极化相关的光学活性和手性活性流体等领域具有潜在用途。然而,这两种运动本质上是耦合的,无法独立控制。此外,它们仅限于小变形,即应变≤2%,这限制了其应用范围。在此,我们构建了模块化手性超材料,由负泊松比平面镶嵌结构和折纸启发的柱状阵列组成,二者具有解耦驱动功能。在单自由度驱动下,该组件能在0°至90°之间扭转,平面内收缩可达25%,平面外收缩超过50%。通过实验和模拟,我们发现该组件的变形包括由旋转方形镶嵌结构主导的平面内扭转和收缩,以及由管状Kresling折纸阵列主导的平面外收缩。此外,我们还展示了两种不同的驱动条件:自由平移时的扭转和自由旋转时的线性位移。我们的超材料建立在高度模块化的组件基础上,可实现可重新编程的不稳定性、局部手性控制、可调负载能力和可扩展性。我们的概念为开发多模态、多稳态和可重新编程的机器提供了途径,可应用于变形机器人、温度调节、滞回环中的机械记忆、非交换状态转换以及用于能量吸收和信息加密的即插即用功能组件等领域。
『总结』 本研究开发了模块化手性超材料,通过解耦驱动实现了多种变形模式,并展示了其在多领域应用的潜力,如变形机器人、温控和加密组件等。
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『Abstract』The peripheral nervous system (PNS) orchestrates organ function in health and disease. Most cancers, including pancreatic ductal adenocarcinoma (PDAC), are infiltrated by PNS neurons, and this contributes to the complex tumour microenvironment (TME) . However, neuronal cell bodies reside in various PNS ganglia, far from the tumour mass. Thus, cancer-innervating or healthy-organ-innervating neurons are lacking in current tissue-sequencing datasets. To molecularly characterize pancreas- and PDAC-innervating neurons at single-cell resolution, we developed Trace-n-Seq. This method uses retrograde tracing of axons from tissues to their respective ganglia, followed by single-cell isolation and transcriptomic analysis. By characterizing more than 5,000 individual sympathetic and sensory neurons, with about 4,000 innervating PDAC or healthy pancreas, we reveal novel neuronal cell types and molecular networks that are distinct to the pancreas, pancreatitis, PDAC or melanoma metastasis. We integrate single-cell datasets of innervating neurons and the TME to establish a neuron–cancer–microenvironment interactome, delineate cancer-driven neuronal reprogramming and generate a pancreatic-cancer nerve signature. Pharmacological denervation induces a pro-inflammatory TME and increases the effectiveness of immune-checkpoint inhibitors. The taxane nab-paclitaxel causes intratumoral neuropathy, which attenuates PDAC growth and, in combination with sympathetic denervation, results in synergistic tumour regression. Our multi-dimensional data provide insights into the networks and functions of PDAC-innervating neurons, and support the inclusion of denervation in future therapies.

『摘要』 外周神经系统(PNS)在健康和疾病状态下协调器官功能。大多数癌症,包括胰腺导管腺癌(PDAC),都有PNS神经元的浸润,这促成了复杂的肿瘤微环境(TME)。然而,神经元胞体驻留在各种PNS神经节中,远离肿瘤肿块。因此,目前的组织测序数据集中缺乏支配癌症或健康器官的神经元数据。为了对支配胰腺和PDAC的神经元进行单细胞分辨率的分子特征分析,我们开发了Trace-n-Seq方法。该方法利用从组织到其各自神经节的轴突逆行追踪,然后进行单细胞分离和转录组分析。通过对5000多个独立的交感神经元和感觉神经元(其中约4000个支配PDAC或健康胰腺)进行特征分析,我们发现了新型神经元细胞类型和分子网络,这些在胰腺、胰腺炎、PDAC或黑色素瘤转移中具有特异性。我们整合了支配神经元的单细胞数据集和TME,建立了神经元-癌症-微环境相互作用组,描绘了癌症驱动的神经元重编程,并生成了胰腺癌神经特征。药物去神经支配可诱导促炎TME,并提高免疫检查点抑制剂的有效性。紫杉烷类药物nab-紫杉醇可引起肿瘤内神经病变,从而抑制PDAC生长,并且与交感去神经支配联合使用可导致肿瘤协同消退。我们的多维数据提供了关于支配PDAC的神经元的网络和功能的见解,并支持在未来的治疗中加入去神经支配手段。
『总结』 研究通过开发Trace-n-Seq方法分析了支配胰腺和PDAC的神经元的分子特征,并揭示了神经元与癌症微环境的相互作用,支持去神经支配作为未来癌症治疗的潜在策略。
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『Abstract』To circumvent CRISPR-Cas immunity, phages express anti-CRISPR factors that inhibit the expression or activities of Cas proteins. Whereas most anti-CRISPRs described to date are proteins, recently described small RNAs called RNA anti-CRISPRs (rAcrs) have sequence homology to CRISPR RNAs (crRNAs) and displace them from cognate Cas nucleases. In this work, we report the discovery of rAcrVIA1—a plasmid-encoded small RNA that inhibits the RNA-targeting CRISPR-Cas13 system in its natural host, Listeria seeligeri . We solved the cryo–electron microscopy structure of the Cas13-rAcr complex, which revealed that rAcrVIA1 adopts a fold nearly identical to crRNA despite sharing negligible sequence similarity. Collectively, our findings expand the diversity of rAcrs and reveal an example of immune antagonism through RNA structural mimicry.

『摘要』 为了规避CRISPR-Cas免疫,噬菌体会表达抗CRISPR因子,这些因子可以抑制Cas蛋白的表达或活性。尽管迄今为止描述的大多数抗CRISPR都是蛋白质,但最近发现的一种被称为RNA抗CRISPR(rAcrs)的小RNA与CRISPR RNA(crRNA)具有序列同源性,并能将其从同源Cas核酸酶中取代出来。在本研究中,我们报告了发现了rAcrVIA1——一种质粒编码的小RNA,它在其自然宿主李斯特菌(Listeria seeligeri)中抑制靶向RNA的CRISPR-Cas13系统。我们解析了Cas13-rAcr复合物的冷冻电子显微镜结构,揭示尽管rAcrVIA1与crRNA的序列相似性微不足道,但它却采用了与crRNA几乎相同的折叠方式。综上所述,我们的研究结果扩展了rAcrs的多样性,并揭示了通过RNA结构模拟进行免疫对抗的一个实例。
『总结』 研究发现了一种新的小RNA(rAcrVIA1),它能抑制李斯特菌中的CRISPR-Cas13系统,且其结构与CRISPR RNA相似但序列不同,揭示了RNA结构模拟在免疫对抗中的作用。
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『Abstract』The DNA damage response (DDR) is a multifaceted network of pathways that preserves genome stability . Unravelling the complementary interplay between these pathways remains a challenge . Here we used CRISPR interference (CRISPRi) screening to comprehensively map the genetic interactions required for survival during normal human cell homeostasis across all core DDR genes. We captured known interactions and discovered myriad new connections that are available online. We defined the molecular mechanism of two of the strongest interactions. First, we found that WDR48 works with USP1 to restrain PCNA degradation in FEN1/LIG1-deficient cells. Second, we found that SMARCAL1 and FANCM directly unwind TA-rich DNA cruciforms, preventing catastrophic chromosome breakage by the ERCC1–ERCC4 complex. Our data yield fundamental insights into genome maintenance, provide a springboard for mechanistic investigations into new connections between DDR factors and pinpoint synthetic vulnerabilities that could be exploited in cancer therapy.

『摘要』 DNA损伤反应(DDR)是一个维持基因组稳定性的多方面通路网络。揭示这些通路之间的互补相互作用仍然是一个挑战。在这里,我们使用CRISPR干扰(CRISPRi)筛选技术,全面绘制了在正常人类细胞稳态期间,所有核心DDR基因生存所需的遗传相互作用图谱。我们捕获了已知的相互作用,并发现了大量可在线获取的新联系。我们阐释了其中两种最强相互作用作用的分子机制。首先,我们发现WDR48与USP1协同作用,在FEN1/LIG1缺乏的细胞中抑制PCNA降解。其次,我们发现SMARCAL1和FANCM可直接解开富含TA的DNA十字形结构,从而防止ERCC1-ERCC4复合物导致的灾难性染色体断裂。我们的数据为基因组维持提供了基本见解,为DDR因子之间新联系的机制研究提供了跳板,并指出了癌症治疗中可能利用的合成致死弱点。
『总结』 本研究通过CRISPR干扰筛选揭示了DDR基因间的相互作用图谱,发现了新联系,并阐释了两种最强相互作用的分子机制,为癌症治疗提供了新视角。
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『Abstract』The eukaryote Tree of Life (eToL) depicts the relationships among all eukaryotic organisms; its root represents the Last Eukaryotic Common Ancestor (LECA) from which all extant complex lifeforms are descended . Locating this root is crucial for reconstructing the features of LECA, both as the endpoint of eukaryogenesis and the start point for the evolution of the myriad complex traits underpinning the diversification of living eukaryotes. However, the position of the root remains contentious due to pervasive phylogenetic artefacts stemming from inadequate evolutionary models, poor taxon sampling and limited phylogenetic signal . Here we estimate the root of the eToL with unprecedented resolution on the basis of a new, much larger, dataset of mitochondrial proteins that includes all known eukaryotic supergroups. Our analyses of a 100 taxon × 93 protein dataset with state-of-the-art phylogenetic models and an extensive evaluation of alternative hypotheses show that the eukaryotic root lies between two multi-supergroup assemblages: ‘Opimoda+’ and ‘Diphoda+’. This position is consistently supported across different models and robustness analyses. Notably, groups containing ‘typical excavates’ are placed on both sides of the root, suggesting the complex features of the ‘excavate’ cell architecture trace back to LECA. This study sheds light on the ancestral cells from which extant eukaryotes arose and provides a crucial framework for investigating the origin and evolution of canonical eukaryotic features.

『摘要』 生命之树(eToL)描述了所有真核生物之间的关系;其根部代表最后的真核生物共同祖先(LECA),所有现存复杂生命形式均源自该祖先。确定这一根部对于重构LECA的特征至关重要,这既是真核生物起源的终点,也是支撑现存真核生物多样化的无数复杂特征进化的起点。然而,由于进化模型不充分、分类群取样不足以及系统发育信号有限,由此产生的普遍存在的系统发育伪影使得根部位置仍然存在争议。在这里,我们基于一组新的、更大的包含所有已知真核生物超群的线粒体蛋白质数据集,以前所未有的分辨率对eToL的根部进行了估算。我们对包含100个分类群和93种蛋白质的数据集,采用最先进的系统发育模型,并对各种假设进行了广泛评估,结果表明,真核生物的根部位于两个多超群组合之间:“Opimoda+”和“Diphoda+”。这一结论在不同模型和稳健性分析中均得到了一致支持。值得注意的是,包含“典型挖掘类生物(excavates)”的类群位于根部的两侧,这表明“挖掘类”细胞结构的复杂特征可追溯至LECA。本研究揭示了现存真核生物起源的祖先细胞,并为探究真核生物典型特征的起源和进化提供了关键框架。
『总结』 本研究基于新的大数据集和先进模型,确定了真核生物生命之树的根部位置,并发现“挖掘类”细胞结构的复杂特征可追溯至最后真核生物共同祖先。
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『Abstract』Ceria nanoparticles supported on alumina are widely used in various catalytic reactions, particularly in conjunction with platinum group metals (PGMs) . Here we found that treating these catalysts at temperatures between 750 and about 1,000 °C in the presence of CO and NO in steam (reactive treatment under reducing atmosphere) leads to the dispersion of ceria nanoparticles into high-density 2D (roughly one atomic layer thin) Ce x O y domains, as confirmed by microscopy, X-ray photoelectron spectroscopy (XPS), X-ray absorption spectroscopy (XAS), infrared spectroscopy and density functional theory (DFT) calculations. These domains, which densely cover the alumina, exhibit substantially enhanced oxygen mobility and storage capacity, facilitating easier extraction of oxygen and the formation of Ce sites and oxygen vacancies. As a result, these catalysts—whether with or without PGMs, such as Rh and Pt—show improved activity for several industrially important catalytic reactions, including NO and N 2 O reduction, as well as CO and NO oxidation, even after exposure to harsh ageing conditions. This study shows a catalyst architecture with superior redox properties under conditions that typically cause sintering, offering a pathway to more efficient metal–ceria catalysts for enhanced general catalysis.

『摘要』 氧化铝负载的氧化铈纳米颗粒广泛用于各种催化反应,特别是与铂族金属(PGMs)结合使用时。本研究发现,在蒸汽中存在一氧化碳和一氧化氮的情况下,将这些催化剂在750至1000°C的温度下进行处理(还原气氛下的反应处理),会导致氧化铈纳米颗粒分散成高密度的二维(大约一个原子层厚度)氧化铈(CeₓOᵧ)畴区,这一结果已通过显微镜、X射线光电子能谱(XPS)、X射线吸收光谱(XAS)、红外光谱和密度泛函理论(DFT)计算得到证实。这些密集覆盖在氧化铝上的畴区表现出显著提高的氧迁移能力和储存能力,从而更容易提取氧并形成铈位点和氧空位。因此,这些催化剂(无论是否含有铑和铂等铂族金属)在经受严苛老化条件后,对多种工业上重要的催化反应(包括一氧化氮和氧化亚氮还原以及一氧化碳和一氧化氮氧化)仍表现出更高的活性。本研究展示了一种在通常会引起烧结的条件下具有优异氧化还原性能的催化剂结构,为开发更高效的金属-氧化铈催化剂以提高整体催化性能提供了一条途径。
『总结』 本研究发现通过还原气氛高温处理,氧化铈纳米颗粒可形成高密度的二维畴区,显著提高了催化剂的氧迁移和储存能力,从而增强了多种工业催化反应的活性。
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『Abstract』Organic farming is often considered to be more sustainable than conventional farming. However, both farming systems comprise highly variable management practices. In this study, we show that in organic and conventional arable fields, the multifunctionality of soils decreases with increasing agricultural management intensity. Soil organic carbon content and bacterial biomass, respectively, were the strongest abiotic and biotic predictors of soil multifunctionality. Greater soil multifunctionality was associated with less-frequent inversion tillage and higher frequency of grass-legume cover cropping, and organic farming did not outperform conventional farming. Our results suggest that reducing management intensity will enhance soil multifunctionality in both conventional and organic farming. This implies that, in contexts where high-yielding, high-intensity agriculture prevails, the paradigm of sustainable intensification should be replaced by “productive deintensification.”

『摘要』 有机农业通常被认为比传统农业更具可持续性。然而,这两种农业系统都包含了差异很大的管理实践。在本研究中,我们发现,在有机和传统的可耕地中,土壤的多功能性随着农业管理强度的增加而降低。土壤有机碳含量和细菌生物量分别是土壤多功能性最强的非生物和生物预测因子。土壤多功能性更强与更少进行翻耕以及更高频率地种植草-豆科覆盖作物相关,而有机农业并未优于传统农业。我们的研究结果表明,降低管理强度将提高传统农业和有机农业的土壤多功能性。这意味着,在高产量、高强度的农业占主导地位的情况下,应以“生产性减密化”取代可持续集约化的范式。
『总结』 研究指出,无论是有机农业还是传统农业,降低管理强度都能提高土壤多功能性,建议在以高产量、高强度为主的农业中采用“生产性减密化”。
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『Abstract』Nuclear star clusters (NSCs) are the densest stellar systems in the Universe. These clusters can be found at the centre of all galaxy types but tend to favour galaxies of intermediate stellar mass around 10 M ⊙ (refs. ). At present, two main processes are under debate to explain their formation: in situ star formation from gas infall and migration and merging of globular clusters (GCs) caused by dynamical friction . Studies of NSC stellar populations suggest that the former predominates in massive galaxies, whereas the latter prevails in dwarf galaxies, and both contribute equally at intermediate mass. However, until now, no ongoing merger of GCs has been observed to confirm this scenario. Here we report the serendipitous discovery of five dwarf galaxies with complex nuclear regions, characterized by multiple nuclei and tidal tails, using high-resolution images from the Hubble Space Telescope. These structures have been reproduced in complementary N -body simulations, supporting the interpretation that they result from migrating and merging of star clusters. The small detection rate and short simulated timescales (below 100 Myr) of this process may explain why this has not been observed previously. This study highlights the need for large surveys with high resolution to fully map the migration scenario steps.

『摘要』 核星团(NSCs)是宇宙中密度最高的恒星系统。这些星团位于所有类型星系的中心,但更倾向于存在于恒星质量约为10^7至10^9太阳质量的中等质量星系中(参考文献)。目前,关于核星团的形成有两种主要机制正在讨论中:一是气体落入导致的原地恒星形成,二是由于动力摩擦引起的球状星团(GCs)迁移和合并。对核星团恒星群体的研究表明,在大型星系中,前者占主导地位,而在矮星系中,后者更为普遍,而在中等质量星系中,两者贡献相当。然而,迄今为止,尚未观察到正在进行中的球状星团合并来证实这一假设。在本文中,我们报告了利用哈勃太空望远镜的高分辨率图像意外发现了五个具有复杂核区域的矮星系,这些区域的特点是有多个核和潮汐尾。已在补充的N体模拟中再现了这些结构,支持了它们是由恒星星团迁移和合并产生的解释。这一过程的检测率低且模拟时间尺度短(低于1亿年),这可能是之前未观察到此现象的原因。本研究强调,需要进行大规模的高分辨率调查,以全面描绘恒星迁移的各个步骤。
『总结』 研究发现五个具有复杂核区域的矮星系,支持了恒星星团迁移和合并是核星团形成机制之一的假设,强调了进行大规模高分辨率调查的必要性。
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『Abstract』The search for simple principles that underlie the spatial structure and dynamics of plant communities is a long-standing challenge in ecology . In particular, the relationship between species coexistence and the spatial distribution of plants is challenging to resolve in species-rich communities . Here we present a comprehensive analysis of the spatial patterns of 720 tree species in 21 large forest plots and their consequences for species coexistence. We show that species with low abundance tend to be more spatially aggregated than more abundant species. Moreover, there is a latitudinal gradient in the strength of this negative aggregation–abundance relationship that increases from tropical to temperate forests. We suggest, in line with recent work , that latitudinal gradients in animal seed dispersal and mycorrhizal associations may jointly generate this pattern. By integrating the observed spatial patterns into population models , we derive the conditions under which species can invade from low abundance in terms of spatial patterns, demography, niche overlap and immigration. Evaluation of the spatial-invasion condition for the 720 tree species analysed suggests that temperate and tropical forests both meet the invasion criterion to a similar extent but through contrasting strategies conditioned by their spatial patterns. Our approach opens up new avenues for the integration of observed spatial patterns into ecological theory and underscores the need to understand the interaction among spatial patterns at the neighbourhood scale and multiple ecological processes in greater detail.

『摘要』 在生态学中,寻找决定植物群落空间结构和动态的简单原则一直是一个长期存在的挑战。尤其是在物种丰富的群落中,物种共存与植物空间分布之间的关系很难厘清。本文综合分析了21个大型森林样地中720个树种的空间分布模式及其对物种共存的影响。研究表明,与数量较多的物种相比,数量较少的物种在空间上往往呈聚集分布。此外,这种负聚集-数量关系的强度随纬度梯度变化,从热带森林到温带森林逐渐增强。根据最近的研究,我们认为动物种子散播和菌根共生关系的纬度梯度变化可能共同导致了这种模式。通过将观察到的空间模式纳入种群模型,我们推导出物种在空间模式、种群统计学、生态位重叠和迁入等方面从低数量入侵的条件。对720个树种的空间入侵条件进行评估后发现,温带森林和热带森林在很大程度上都符合入侵标准,但二者采取的策略截然不同,这些策略受其空间模式的制约。我们的研究方法为将观察到的空间模式纳入生态理论开辟了新途径,并强调需要更详细地了解邻域尺度的空间模式与多种生态过程之间的相互作用。
『总结』 本研究通过分析720个树种的空间分布模式,发现物种数量与其空间聚集程度呈负相关,且这种关系随纬度变化,并进一步探讨了其对物种共存及生态理论的影响。
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『Abstract』Starting at middle age, adults often suffer from visceral adiposity and associated adverse metabolic disorders. Lineage tracing in mice revealed that adipose progenitor cells (APCs) in visceral fat undergo extensive adipogenesis during middle age. Thus, despite the low turnover rate of adipocytes in young adults, adipogenesis is unlocked during middle age. Transplantations quantitatively showed that APCs in middle-aged mice exhibited high adipogenic capacity cell-autonomously. Single-cell RNA sequencing identified a distinct APC population, the committed preadipocyte, age-enriched (CP-A), emerging at this age. CP-As demonstrated elevated proliferation and adipogenesis activity. Pharmacological and genetic manipulations indicated that leukemia inhibitory factor receptor signaling was indispensable for CP-A adipogenesis and visceral fat expansion. These findings uncover a fundamental mechanism of age-dependent adipose remodeling, offering critical insights into age-related metabolic diseases.

『摘要』 从中年开始,成年人经常遭受内脏肥胖和相关的不良代谢紊乱。小鼠谱系追踪研究显示,中年期间内脏脂肪中的脂肪祖细胞(APCs)会经历大量的脂肪生成。因此,尽管年轻成年人的脂肪细胞更新率较低,但在中年时期脂肪生成会被激活。移植实验定量表明,中年小鼠的APCs表现出高水平的细胞自主脂肪生成能力。单细胞RNA测序发现了一种在中年时出现的独特APCs群体——定向脂肪前体细胞(CP-A)。CP-As表现出增殖和脂肪生成活性增强。药理学和遗传学研究表明,白血病抑制因子受体信号对CP-A的脂肪生成和内脏脂肪扩张至关重要。这些发现揭示了年龄依赖性脂肪重塑的基本机制,为理解年龄相关代谢疾病提供了关键见解。
『总结』 研究发现中年时期脂肪祖细胞经历大量脂肪生成,揭示了年龄依赖性脂肪重塑机制,对理解年龄相关代谢疾病有重要意义。
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『Abstract』Chemical recycling to monomers is a key strategy for a sustainable circular polymer economy. However, most efforts have focused on polymers with carbon backbones. Recycling of silicone polymers and corresponding materials, featuring a robust inorganic backbone and tunable properties, remains in its infancy. We present a general method for depolymerization of a very wide range of silicone-based materials and postconsumer waste, including end-of-life cross-linked polydimethylsiloxane-based networks within formulated materials. The reaction proceeds at 40°C, harnessing an efficient gallium catalyst for a million-fold rate enhancement and boron trichloride as the chlorine source, to produce nearly quantitative yields of (methyl)chlorosilanes, key intermediates in the Muller-Rochow process that anchors the silicone industry.

『摘要』 化学回收至单体是实现可持续循环聚合物经济的关键策略。然而,目前大多数研究都集中在碳链聚合物上。硅酮聚合物及其相关材料具有坚固的无机骨架和可调的特性,但其回收技术尚处于起步阶段。本研究提出了一种通用方法,用于解聚多种硅基材料和消费后废弃物,包括配方材料中使用寿命到期的交联聚二甲基硅氧烷基网络。该反应在40°C下进行,利用高效的镓催化剂实现百万倍的速率提升,并以三氯化硼作为氯源,几乎定量地产出(甲基)氯硅烷,这是奠定硅酮工业基础的Muller-Rochow工艺中的关键中间体。
『总结』 本研究提出了一种新方法,能够有效解聚多种硅基材料及废弃物,利用镓催化剂和三氯化硼,高产率得到硅酮工业的关键中间体。
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『Abstract』Metastasis is the spread of cancer cells from primary tumours to distant organs and is the cause of 90% of cancer deaths globally . Metastasizing cancer cells are uniquely vulnerable to immune attack, as they are initially deprived of the immunosuppressive microenvironment found within established tumours . There is interest in therapeutically exploiting this immune vulnerability to prevent recurrence in patients with early cancer at risk of metastasis. Here we show that inhibitors of cyclooxygenase 1 (COX-1), including aspirin, enhance immunity to cancer metastasis by releasing T cells from suppression by platelet-derived thromboxane A 2 (TXA 2 ). TXA 2 acts on T cells to trigger an immunosuppressive pathway that is dependent on the guanine exchange factor ARHGEF1, suppressing T cell receptor-driven kinase signalling, proliferation and effector functions. T cell-specific conditional deletion of Arhgef1 in mice increases T cell activation at the metastatic site, provoking immune-mediated rejection of lung and liver metastases. Consequently, restricting the availability of TXA 2 using aspirin, selective COX-1 inhibitors or platelet-specific deletion of COX-1 reduces the rate of metastasis in a manner that is dependent on T cell-intrinsic expression of ARHGEF1 and signalling by TXA 2 in vivo. These findings reveal a novel immunosuppressive pathway that limits T cell immunity to cancer metastasis, providing mechanistic insights into the anti-metastatic activity of aspirin and paving the way for more effective anti-metastatic immunotherapies.

『摘要』 转移是指癌细胞从原发肿瘤扩散到远端器官,这是全球90%癌症死亡的原因。转移中的癌细胞尤其容易受到免疫攻击,因为它们最初缺乏已建立肿瘤中存在的免疫抑制微环境。人们有兴趣利用这种免疫易感性进行治疗,以防止有转移风险的早期癌症患者复发。本研究表明,环氧合酶1(COX-1)抑制剂(包括阿司匹林)可通过解除血小板衍生的血栓烷A2(TXA2)对T细胞的抑制来增强对癌症转移的免疫力。TXA2作用于T细胞,触发一条依赖于鸟嘌呤交换因子ARHGEF1的免疫抑制途径,抑制T细胞受体驱动的激酶信号传导、增殖和效应功能。在小鼠体内特异性条件性敲除T细胞的Arhgef1,可增加转移部位的T细胞活化,引发免疫介导的肺和肝转移排斥反应。因此,通过使用阿司匹林、选择性COX-1抑制剂或血小板特异性敲除COX-1来限制TXA2的可利用性,可降低转移率,这种方式依赖于T细胞内在表达的ARHGEF1和体内TXA2的信号传导。这些研究结果揭示了一条限制T细胞对癌症转移免疫力的新型免疫抑制途径,为阿司匹林的抗转移活性提供了机制见解,并为更有效的抗转移免疫疗法铺平了道路。
『总结』 本研究表明阿司匹林等COX-1抑制剂通过阻断TXA2介导的免疫抑制途径,增强了T细胞对癌症转移的免疫力,为开发更有效的抗转移免疫疗法提供了新视角。
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『Abstract』Successful cancer immunotherapy requires a patient to mount an effective immune response against tumors; however, many cancers evade the body’s immune system. To investigate the basis for treatment failure, we examined spontaneous mouse models of hepatocellular carcinoma (HCC) with either an inflamed T cell–rich or a noninflamed T cell–deprived tumor microenvironment (TME). Our studies reveal that erythropoietin (EPO) secreted by tumor cells determines tumor immunotype. Tumor-derived EPO autonomously generates a noninflamed TME by interacting with its cognate receptor EPOR on tumor-associated macrophages (TAMs). EPO signaling prompts TAMs to become immunoregulatory through NRF2-mediated heme depletion. Removing either tumor-derived EPO or EPOR on TAMs leads to an inflamed TME and tumor regression independent of genotype, owing to augmented antitumor T cell immunity. Thus, the EPO/EPOR axis functions as an immunosuppressive switch for antitumor immunity.

『摘要』 成功的癌症免疫治疗需要患者对肿瘤产生有效的免疫反应;然而,许多癌症能够逃避人体的免疫系统。为了探究治疗失败的原因,我们研究了具有炎性T细胞富集型或非炎性T细胞缺乏型肿瘤微环境(TME)的自发性小鼠肝细胞癌(HCC)模型。我们的研究表明,肿瘤细胞分泌的促红细胞生成素(EPO)决定了肿瘤的免疫类型。肿瘤来源的EPO通过与肿瘤相关巨噬细胞(TAM)上的同源受体EPOR相互作用,自主生成非炎性TME。EPO信号通过NRF2介导的血红素耗竭促使TAM发挥免疫调节作用。去除肿瘤来源的EPO或TAM上的EPOR,可因抗肿瘤T细胞免疫增强而导致炎性TME和肿瘤消退,且与基因型无关。因此,EPO/EPOR轴是抗肿瘤免疫的免疫抑制开关。
『总结』 研究发现肿瘤细胞分泌的EPO通过与TAM上的EPOR相互作用,形成了免疫抑制的微环境,是免疫治疗失败的原因之一。
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『Abstract』Protein polymer scaffolds composed of death fold (DF) proteins are critical to the formation of signalosomes in immune signaling. The biophysical properties that these polymeric scaffolds require for signal transduction are not clearly defined. Here, we engineered single-component DF signalosomes. We found that functionality depends on the stability provided by the DF polymer, which could also be achieved with a bacterial DF domain, a synthetic filament-forming domain, and amyloid-like sequences. This demonstrates the importance of polymer stability and inducibility irrespective of the motif’s origin. By varying the number of included TRAF6 interaction motifs, we demonstrate that avidity is a tunable property that can control the amplitude of signaling outputs. This work lays out a reductionist framework to elucidate the required signaling properties through polymeric scaffolds by adjusting their assembly kinetics, stability, and avidity.

『摘要』 由死亡折叠(DF)蛋白组成的蛋白质聚合物支架对于免疫信号传导中的信号复合体形成至关重要。这些聚合物支架用于信号传导所需的生物物理特性尚不明确。本研究构建了单组分DF信号复合体。我们发现,功能性取决于DF聚合物提供的稳定性,而这种稳定性也可以通过细菌DF结构域、合成纤维形成结构域和类淀粉样序列来实现。这表明,无论基序的来源如何,聚合物稳定性和可诱导性都很重要。通过改变所包含的TRAF6相互作用基序的数量,本研究证明亲合力是一种可调特性,能够控制信号输出的幅度。本研究建立了一个还原论框架,通过调整聚合物支架的组装动力学、稳定性和亲合力来阐明其所需的信号传导特性。
『总结』 本研究通过构建单组分DF信号复合体,揭示了聚合物支架的稳定性和亲合力对信号传导的重要性,并提出了一个通过调整支架特性来阐明其信号传导功能的框架。
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『Abstract』The stability of hazardous volcanic systems is strongly influenced by the uppermost magma storage depth and volatile exsolution . Despite abundant evidence for an upper crustal magma reservoir beneath Yellowstone caldera , its depth and the properties at its top have not been well constrained. New controlled-source seismic imaging illuminates a sharp reflective cap of the magma reservoir approximately 3.8 km beneath the northeastern caldera. Magma ascent to such low pressure is expected to drive volatile exsolution and potentially localized accumulation of bubbles near the top of the reservoir , but this process typically remains hidden in contemporary volcanic systems. P-wave and P-to-S-wave reflections from the sharp top of the Yellowstone magma reservoir indicate that a mixture of supercritical fluid and magma fills the pore space at the cap of the approximately 3–8-km-deep low-shear-velocity layer imaged by seismic tomography . The results are consistent with partial retention of bubbles exsolved from an upper crustal reservoir with ongoing magma supply from a volatile-enriched mantle source. Bubble accumulation can eventually lead to reservoir instability , but the bubble volume fraction seismically estimated at the top of the reservoir today is lower than typical estimates of pre-eruptive conditions for rhyolites , and measurements of the hydrothermal system document high fluxes of magmatic volatiles escaping to the surface . We infer that the magma reservoir is in a stable state of efficient bubble ascent into the hydrothermal system on the basis of estimates that it is a crystal-rich (less than 30% porosity) reservoir for which dynamic modelling favours channelized bubble escape that prevents instability .

『摘要』 危险火山系统的稳定性受到最上部岩浆储存深度和挥发分释放的强烈影响。尽管有大量证据表明黄石火山口下存在一个上地壳岩浆库,但其深度和顶部特性尚未明确。新的可控震源地震成像显示,火山口东北部下方约3.8公里处有一个岩浆库的清晰反射盖层。岩浆上升到如此低的压力区域,预计会驱动挥发分的释放,并可能在岩浆库顶部附近形成局部气泡聚集,但这一过程在当代火山系统中通常难以察觉。来自黄石岩浆库顶部清晰界面的P波和P-S转换波反射表明,超临界流体和岩浆的混合物填充了地震层析成像显示的约3-8公里深的低剪切速度层顶部的孔隙空间。这些结果与上地壳岩浆库中部分气泡留存以及富含挥发分的地幔源持续供应岩浆的情况相符。气泡聚集最终可能导致岩浆库失稳,但根据地震估算,如今岩浆库顶部的气泡体积分数低于流纹岩喷发前条件的典型估算值,而热液系统的测量结果显示,有大量岩浆挥发分逃逸到地表。我们推断,根据估计,该岩浆库是一个富含晶体(孔隙率小于30%)的岩浆库,动态模拟显示其倾向于通道化气泡逃逸,从而防止失稳,因此该岩浆库处于气泡有效上升至热液系统的稳定状态。
『总结』 新研究表明,黄石火山下方的岩浆库目前处于稳定状态,尽管存在气泡聚集和挥发分释放的过程,但气泡通过通道化逃逸防止了岩浆库失稳。
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『Abstract』Lepidoptera is the most herbivorous of all the insect orders, with predatory caterpillars globally comprising less than 0.13% of the nearly 200,000 moth and butterfly species. Here, we report a species in which caterpillars are carnivorous inhabitants of spider’s webs, feeding on the arthropods that they find there. This Hawaiian lineage also boasts an unprecedented and macabre practice of decorating its portable larval home with the body parts of the spider prey it harvests from the web where it resides. Phylogenomic data suggest that the origin of this unique spider cohabitant is at least six million years old, more than one million years older than Hawaii’s current high islands. After decades of searching, only one species has been discovered, and it is restricted to 15 square kilometers of a single mountain range on the island of Oʻahu, meaning that other members of the lineage have disappeared from older islands. Conservation action to save this globally unique lineage is imperative and overdue.

『摘要』 鳞翅目是昆虫纲中最具草食性的目,而在全球近20万种蛾类和蝴蝶种类中,食肉性的毛毛虫占比不到0.13%。本研究报告了一种毛毛虫新物种,它们以蜘蛛网为栖息地,捕食网上的节肢动物为食。这种夏威夷毛毛虫还会用一种前所未有的诡异方式装饰其便携式的幼虫居所,即用它们从栖息的蜘蛛网上捕获的蜘蛛猎物身体部位来装点。基因组系统发育学数据表明,这种独特的蜘蛛共生物种的起源至少可以追溯到600万年前,比夏威夷现有的高岛形成还要早100多万年。经过数十年的搜寻,仅发现了一个物种,而且它仅限于欧胡岛上单一山脉的15平方公里范围内,这意味着该物种的其他成员已经从更古老的岛屿上消失了。采取保护行动拯救这一全球独一无二的物种刻不容缓。
『总结』 研究发现了一种以蜘蛛网为栖息地并捕食网上节肢动物的夏威夷毛毛虫新物种,该物种装饰居所的方式独特且起源古老,但目前仅存于欧胡岛一隅,亟需保护。
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『Abstract』Human accelerated regions (HARs) are conserved genomic loci that have experienced rapid nucleotide substitutions following the divergence from chimpanzees . HARs are enriched in candidate regulatory regions near neurodevelopmental genes, suggesting their roles in gene regulation . However, their target genes and functional contributions to human brain development remain largely uncharacterized. Here we elucidate the cis -regulatory functions of HARs in human and chimpanzee induced pluripotent stem (iPS) cell-induced excitatory neurons. Using genomic and chromatin looping information, we prioritized 20 HARs and their chimpanzee orthologues for functional characterization via single-cell CRISPR interference, and demonstrated their species-specific gene regulatory functions. Our findings reveal diverse functional outcomes of HAR-mediated cis -regulation in human neurons, including attenuated NPAS3 expression by altering the binding affinities of multiple transcription factors in HAR202 and maintaining iPS cell pluripotency and neuronal differentiation capacities through the upregulation of PUM2 by 2xHAR.319. Finally, we used prime editing to demonstrate differential enhancer activity caused by several HAR26;2xHAR.178 variants. In particular, we link one variant in HAR26;2xHAR.178 to elevated SOCS2 expression and increased neurite outgrowth in human neurons. Thus, our study sheds new light on the endogenous gene regulatory functions of HARs and their potential contribution to human brain evolution.

『摘要』 人类加速区(HARs)是保守的基因组位点,在与黑猩猩分歧后经历了快速的核苷酸替代。HARs在神经发育基因附近的候选调控区域中高度富集,表明其在基因调控中的作用。然而,HARs的靶基因及其对人类大脑发育的功能贡献仍大多未知。本研究阐明了HARs在人类和黑猩猩诱导多能干细胞(iPS)诱导的兴奋性神经元中的顺式调控功能。利用基因组和染色质环化信息,本研究优先选择了20个HARs及其黑猩猩直系同源序列,通过单细胞CRISPR干扰进行功能表征,并验证了它们的物种特异性基因调控功能。研究发现,HAR介导的人类神经元中的顺式调控产生了多种功能结果,包括通过改变HAR202中多个转录因子的结合亲和力来减弱NPAS3表达,以及通过2xHAR.319上调PUM2来维持iPS细胞的多能性和神经元分化能力。最后,本研究利用首相编辑技术证明了几个HAR26;2xHAR.178变异体引起的增强子活性差异。特别是,本研究将HAR26;2xHAR.178中的一个变异体与人类神经元中SOCS2表达升高和神经突生长增加联系起来。因此,本研究揭示了HARs的内源性基因调控功能及其对人类大脑进化潜在贡献的新见解。
『总结』 本研究发现了人类加速区(HARs)在人类和黑猩猩神经元中的顺式调控功能,并揭示了HARs对人类大脑发育和进化的潜在贡献。
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