Science, 19 Jun 2025, VOL 388, ISSUE 6753

《科学》2025年6月19日，第388卷，6753期

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生物学Biology

Sleep need–dependent plasticity of a thalamic circuit promotes homeostatic recovery sleep

睡眠需求依赖性丘脑回路可塑性促进稳态恢复性睡眠

▲ 作者：Sang Soo Lee, Qiang Liu et al.

▲链接：

https://www.science.org/doi/10.1126/science.adm8203

▲ 摘要：长时间清醒会导致持续而深度的恢复性睡眠（RS）。然而，介导这一过程的神经回路机制仍未明晰。通过对小鼠进行神经回路筛查，研究人员发现了一组在睡眠剥夺（SD）期间被激活、且对睡眠稳态有必要性的丘脑室旁核（RE）神经元。光遗传学激活RE神经元会产生一种特殊表型：小鼠先出现睡前行为（理毛和整理巢穴），随后进入类似于RS的长时间深度睡眠。

在SD期间抑制RE神经元活动会损害后续的RS，表明这些神经元传递睡眠需求信号。RE神经元作用于促睡眠区未定带细胞的上游，且SD会引发该回路的可塑性变化以增强其连接强度。这些发现揭示了睡眠需求通过改变睡眠回路的功能耦合，以促进持续深度睡眠的神经机制。

▲ Abstract：Prolonged wakefulness leads to persistent, deep recovery sleep (RS). However, the neuronal circuits that mediate this process remain elusive. From a circuit screen in mice, we identified a group of thalamic nucleus reuniens (RE) neurons activated during sleep deprivation (SD) and required for sleep homeostasis. Optogenetic activation of RE neurons leads to an unusual phenotype: presleep behaviors (grooming and nest organizing) followed by prolonged, intense sleep that resembles RS. Inhibiting RE activity during SD impairs subsequent RS, which suggests that these neurons signal sleep need. RE neurons act upstream of sleep-promoting zona incerta cells, and SD triggers plasticity of this circuit to strengthen their connectivity. These findings reveal a circuit mechanism by which sleep need transforms the functional coupling of a sleep circuit to promote persistent, deep sleep.

化学Chemistry

Limitations of chemical monitoring hinder aquatic risk evaluations on the macroscale

化学监测的局限性制约大尺度水生风险评估

▲ 作者：Sascha Bub, Lara L. Petschick  et al.

▲链接：

https://www.science.org/doi/10.1126/science.adn5356

▲摘要：大尺度化学监测数据评估需要化学物质、空间和时间三维信息的整合。在此，研究人员关联了美国6400万条地表水监测记录（涉及1900种化学物质，时间跨度为1958至2019年，覆盖31万个监测站点）以及3700万条分析检测限与体内/体外毒性阈值数据。研究发现，在约29.7万种潜在环境关注化学物质中，可用于回溯性风险评估的暴露数据不足1%。

与20世纪70年代主要监测持久性无机污染物的情况不同，现行监测体系对大量有机化学物质及其降解产物的管控存在明显缺失。监测的化学覆盖度和空间覆盖度不足，加之部分高毒性物质的检测限值设置过高，导致重要化学物质的风险认知存在系统性偏差。

▲ Abstract：Macroscale evaluations of chemical monitoring data require the integration of chemical, spatial, and temporal dimensions. Here, we linked 64 million US surface water monitoring records (1900 chemicals, date range 1958 to 2019, 310,000 sites) and 37 million analytical limits and in vivo and in silico toxicity thresholds. We found that the exposure data required for retrospective risk assessment were available for less than 1% of chemicals with potential environmental concern (n ≈ 297,000). In contrast to the situation with persistent and often inorganic contaminants in the 1970s, current monitoring schemes lack control of a much larger number of organic chemicals and their degradates. Insufficient chemical and spatial coverage of monitoring, along with analytical limits being far too high to track some of the most toxic chemicals, biases risk perceptions for important chemicals.

Excision of organic macrocycles from covalent organic frameworks

共价有机框架中有机大环结构的精确切除

▲ 作者：Roberto Sánchez-Naya, Juan Pablo Cavalieri et al.

▲链接：

https://www.science.org/doi/10.1126/science.adw4126

▲摘要：传统分子合成通常通过简单分子前体间的分步反应实现。该研究报道了一种基于"剪裁化学"方法的有机分子合成新方法，可以从有序延伸的有机结构中精准切除目标分子。

研究人员通过选择性切割共价有机框架，成功制备了系列大环化合物：包括8种环原子数为114、138和162的大环聚酰胺，以及1种114原子环的大环聚酰亚胺。这种分子切除策略将有机合成的适用范围拓展至传统方法难以获得的大分子体系。

▲ Abstract：Molecules are typically synthesized through stepwise processes involving chemical reactions between simple molecular precursors. Here, we report an advance in the synthesis of new organic molecules based on the approach of clip-off chemistry, in which molecules are excised from ordered, extended organic structures. We synthesized macrocycles by selectively cleaving them out of covalent organic frameworks. The synthesized macrocycles include eight macrocyclic polyamides with 114-, 138-, and 162-atom rings, and one 114-atom ring macrocyclic polyimide. This excision approach expands the scope of chemical organic synthesis to previously inaccessible macromolecules.

动物学Zoology

Molecular evolution of sour tolerance in birds

鸟类酸味耐受性的分子演化机制

▲ 作者：Hao Zhang, Lei Luo et al.

▲链接：

https://www.science.org/doi/10.1126/science.adr7946

▲ 摘要：味觉仔塑造动物感知中非常关键。哺乳动物对作为基本味觉之一的酸味具有排斥性，而许多鸟类却经常取食酸性果实，暗示其可能存在酸味耐受机制。该研究揭示了鸟类酸味耐受的分子基础涉及酸味受体[otopetrin 1（OTOP1）]的适应性改变。

研究展示了酸味耐受是鸟类的保守性状，禽类OTOP1表现出酸诱导抑制特性，以及OTOP1调控直接影响酸味感知与耐受能力。通过祖先序列重建发现，酸味耐受能力的提升与鸣禽类群重获甜味感知能力可能处于相同的演化节点。这一转变可能使得鸣禽得以取食更广泛的水果资源，影响了这一种群的演化辐射与多样性形成。

▲ Abstract：Taste is crucial in shaping animal perception. Sourness, one of the primary tastes, is aversive in mammals, whereas many birds frequently consume acidic fruits, suggesting a potential tolerance. Our study uncovers a mechanism enabling avian sour tolerance that involves changes to the sour receptor [otopetrin 1 (OTOP1)]. We demonstrate that sour tolerance is a conserved trait in birds, with avian OTOP1 exhibiting acid-induced inhibition and OTOP1 modulation affecting sour perception and tolerance. Ancestral reconstruction reveals that the increase in acid tolerance may have evolved at the same point in the songbird phylogeny as the regain of sweet sensing in this clade. This shift might have enabled songbirds to feed on a wider range of fruits, affecting the evolution and diversification of the songbird radiation.

地球科学Earth Science

Greener green and bluer blue: Ocean poleward greening over the past two decades

更绿的绿，更蓝的蓝：过去二十年海洋极地绿化现象

▲ 作者：Haipeng Zhao, Manfredi Manizza et al.

▲链接：

https://www.science.org/doi/10.1126/science.adr9715

▲ 摘要：尽管气候变化导致的陆地绿化现象已有充分记载，海洋中的类似趋势却没有被彻底研究。基于卫星观测的海洋叶绿素a（Chl）浓度数据，该研究展示了表层海洋在2003至2022年间呈现显著的向极地绿化趋势。

与此同时，北半球副热带海域叶绿素浓度持续下降。通过构建不平等指数发现，这种叶绿素浓度的纬度差异在过去二十年持续扩大，在北半球表现尤为突出。

水温上升可能是驱动叶绿素变化的主因。这种以海水"更绿的绿，更蓝的蓝"为标志的叶绿素分布失衡现象，可能通过营养级联效应影响高营养级生物，进而对沿海国家渔业与经济产生深远影响。

▲ Abstract：Although the global greening associated with climate change is well documented on land, similar trends in the ocean have not been thoroughly identified. Using satellite observations of ocean chlorophyll a (Chl) concentration, we show that the surface ocean experienced a poleward greening from 2003 to 2022. Contemporaneously, the subtropical regions of the Northern Hemisphere experienced a decrease in Chl. As such, the latitudinal disparity in Chl, as documented by an inequality index, has been increasing over the past two decades, particularly in the Northern Hemisphere. Rising water temperatures may primarily influence the Chl trends. The increasing Chl inequality—marked by “greener green and bluer blue” waters—has the potential to cascade to higher trophic levels, with implications for the fisheries and economies of coastal nations.

Plastic bag bans and fees reduce harmful bag litter on shorelines

塑料袋禁令与收费政策有效减少海岸线有害塑料袋污染

▲ 作者：Anna Papp and Kimberly L. Oremus

▲链接：

https://www.science.org/doi/10.1126/science.adp9274

▲摘要：塑料污染正严重威胁海洋及淡水生态系统及其生态服务功能。尽管全球范围越来越普遍实施内塑料袋禁令与税费政策，但其减少塑料垃圾的实际效果尚不明确。

利用美国不同地理尺度上实施的差异化塑料袋政策，结合公民科学项目收集的45067次海岸线清理数据，该研究系统评估了政策对塑料袋垃圾的影响。

研究发现，相较于无政策地区，实施塑料袋政策的区域在清理垃圾中塑料袋占比下降25%至47%，其中税费政策可能对海岸线垃圾的减排效果更显著。当前，一方面多国政府正考虑出台塑料袋管制政策，另一方面部分地区却通过立法阻挠此类政策推行。该研究为塑料袋政策能有效缓解海岸线塑料污染问题提供了证据。

▲ Abstract：Plastic pollution threatens marine and freshwater ecosystems and the services they provide. Although plastic bag bans and taxes are increasingly implemented worldwide, their effectiveness in reducing plastic litter remains unknown. Leveraging the patchwork of bag policies across different geographic scales in the United States and citizen science data on 45,067 shoreline cleanups, we assess the impact of these policies on plastic bag litter. We find that plastic bag policies lead to a 25 to 47% decrease in plastic bags as a share of total items collected at cleanups relative to areas without policies, with taxes possibly further reducing shoreline litter. At a time when many jurisdictions are considering bag policies, while others are preemptively prohibiting them, our study provides evidence that they mitigate shoreline plastic pollution.