Nature
Nature is the foremost international weekly scientific journal in the world and is the flagship journal for Nature Portfolio. It publishes the finest peer-reviewed research in all fields of science and technology on the basis of its originality, importance, interdisciplinary interest, timeliness, accessibility, elegance and surprising conclusions. Nature publishes landmark papers, award winning news, leading comment and expert opinion on important, topical scientific news and events that enable readers to share the latest discoveries in science and evolve the discussion amongst the global scientific community.
Single-use plastics are everywhere — but two researchers are redefining the norm and championing sustainability. Single-use plastics are everywhere — but two researchers are redefining the norm and championing sustainability.
Leopard-spotted rocks are ‘an intriguing signal’ of microbial life on Mars. Plus, should the infamous Stanford Prison Experiment be retracted? Leopard-spotted rocks are ‘an intriguing signal’ of microbial life on Mars. Plus, should the infamous Stanford Prison Experiment be retracted?
A huge haul of 128 newfound satellites might be a hint of past collisions in the planet’s orbit, or something else. A huge haul of 128 newfound satellites might be a hint of past collisions in the planet’s orbit, or something else.
A well-timed atmospheric river dropped enough snow on Greenland for its ice sheet to lose 8% less mass than expected. A well-timed atmospheric river dropped enough snow on Greenland for its ice sheet to lose 8% less mass than expected.
Failure to agree on global grants to help low- and middle-income countries to achieve net-zero emissions cannot be the end of the story. An urgent solution is needed. Failure to agree on global grants to help low- and middle-income countries to achieve net-zero emissions cannot be the end of the story. An urgent solution is needed.
The device, to be tested in more people, could be used as a temporary measure for those waiting for a donor organ. The device, to be tested in more people, could be used as a temporary measure for those waiting for a donor organ.
Fears are rising that infectious diseases such as measles could make a comeback now that the anti-vaccine advocate is in charge of the US public-health system. Fears are rising that infectious diseases such as measles could make a comeback now that the anti-vaccine advocate is in charge of the US public-health system.
In the wake of the Trump administration’s funding freezes and job cuts, some researchers are planning their next move. In the wake of the Trump administration’s funding freezes and job cuts, some researchers are planning their next move.
Blue-lined octopuses immobilize their partners with venom to avoid being eaten after sex. Plus, astronomers have discovered 128 new moons orbiting Saturn. Blue-lined octopuses immobilize their partners with venom to avoid being eaten after sex. Plus, astronomers have discovered 128 new moons orbiting Saturn.
The intriguing chemistry of a rock collected by the Perseverance rover could trace to microbial activity — or not. The intriguing chemistry of a rock collected by the Perseverance rover could trace to microbial activity — or not.
Scientists also identified anti-ageing drugs and experimental compounds that could target the genes to reverse decline. Scientists also identified anti-ageing drugs and experimental compounds that could target the genes to reverse decline.
Nature - Reply to: Weather anomalies cannot explain insect decline
The firm has incorporated its Gemini artificial-intelligence model into robots to perform fiddly tasks. The firm has incorporated its Gemini artificial-intelligence model into robots to perform fiddly tasks.
Technique could help researchers probe strange properties of 2D metals — plus, five years after the pandemic, how did COVID change virology? Hear the biggest stories from the world of science | 12 March 2025
Nature - Weather anomalies cannot explain insect decline
State-of-the-art climate models project a substantial decline in precipitation for the Mediterranean region in the future1. Supporting this notion, several studies based on observed precipitation data spanning recent decades have suggested a decrease in Mediterranean precipitation2–4, with some attributing a large fraction of this change to anthropogenic influences3,5. Conversely, certain researchers have underlined that Mediterranean precipitation exhibits considerable spatiotemporal variability driven by atmospheric circulation patterns6,7 maintaining stationarity over the long term8,9. These conflicting perspectives underscore the need for a comprehensive assessment of precipitation changes in this region, given the profound social, economic and environmental implications. Here we show that Mediterranean precipitation has largely remained stationary from 1871 to 2020, albeit with significant multi-decadal and interannual variability. This conclusion is based on the most comprehensive dataset available for the region, encompassing over 23,000 stations across 27 countries. While trends can be identified for some periods and subregions, our findings attribute these trends primarily to atmospheric dynamics, which would be mostly linked to internal variability. Furthermore, our assessment reconciles the observed precipitation trends with Coupled Model Intercomparison Project Phase 6 model simulations, neither of which indicate a prevailing past precipitation trend in the region. The implications of our results extend to environmental, agricultural and water resources planning in one of the world’s prominent climate change hotspots10. Our assessment of a 27-country weather station dataset in the Mediterranean region revealed long-term stability in precipitation over 150 years, along with substantial short-term variability on annual to decadal scales driven by atmospheric circulation; these findings align with the precipitation trends seen in CMIP6 models.
Antigenic variation is an immune evasion strategy used by many different pathogens. It involves the periodic, non-random switch in the expression of different antigens throughout an infection. How the observed hierarchy in antigen expression is achieved has remained a mystery1,2. A key challenge in uncovering this process has been the inability to track transcriptome changes and potential genomic rearrangements in individual cells during a switch event. Here we report the establishment of a highly sensitive single-cell RNA sequencing approach for the model protozoan parasite Trypanosoma brucei. This approach has revealed genomic rearrangements that occur in individual cells during a switch event. Our data show that following a double-strand break in the transcribed antigen-coding gene—an important trigger for antigen switching—the type of repair mechanism and the resultant antigen expression depend on the availability of a homologous repair template in the genome. When such a template was available, repair proceeded through segmental gene conversion, creating new, mosaic antigen-coding genes. Conversely, in the absence of a suitable template, a telomere-adjacent antigen-coding gene from a different part of the genome was activated by break-induced replication. Our results show the critical role of repair sequence availability in the antigen selection mechanism. Furthermore, our study demonstrates the power of highly sensitive single-cell RNA sequencing methods in detecting genomic rearrangements that drive transcriptional changes at the single-cell level. A highly sensitive single-cell RNA sequencing approach reveals genomic features controlling the order of antigen activation in the model protozoan parasite Trypanosoma brucei.
Crop production faces persistent threats from insect-vector-borne viral diseases1,2. Recent advancements have revealed the intricate immune mechanisms that plants deploy against viral pathogens3–8. However, the molecular mechanisms through which plant hosts recognize viral infections and initiate antiviral defence at disease onset have not been elucidated. Here, through the natural infection of rice by inoculation with insect vectors carrying the natural forms of viruses, we show that viral coat proteins are perceived by the RING1–IBR–RING2-type ubiquitin ligase (RBRL), initiating the first step of the natural antiviral response in rice. RBRL subsequently targets an adaptor protein of the transcriptional repression complex of the jasmonate pathway, NOVEL INTERACTOR OF JAZ 3 (NINJA3), for degradation through the ubiquitination system, inducing jasmonate signalling and activating downstream antiviral defence. We further show that this phenomenon is a universal molecular mechanism used by rice plants to perceive viral infections and initiate antiviral signalling cascades. This approach is important not only for obtaining a deeper understanding of virus–host interactions but also for further disease resistance breeding. Viral coat proteins are perceived by the RING1–IBR–RING2-type ubiquitin ligase, initiating the first step of the natural antiviral response in rice.
In a subset of children and adolescents, SARS-CoV-2 infection induces a severe acute hyperinflammatory shock1 termed multisystem inflammatory syndrome in children (MIS-C) at four to eight weeks after infection. MIS-C is characterized by a specific T cell expansion2 and systemic hyperinflammation3. The pathogenesis of MIS-C remains largely unknown. Here we show that acute MIS-C is characterized by impaired reactivation of virus-reactive memory T cells, which depends on increased serum levels of the cytokine TGFβ resembling those that occur during severe COVID-19 (refs. 4,5). This functional impairment in T cell reactivity is accompanied by the presence of TGFβ-response signatures in T cells, B cells and monocytes along with reduced antigen-presentation capabilities of monocytes, and can be reversed by blocking TGFβ. Furthermore, T cell receptor repertoires of patients with MIS-C exhibit expansion of T cells expressing TCRVβ21.3, resembling Epstein–Barr virus (EBV)-reactive T cell clones capable of eliminating EBV-infected B cells. Additionally, serum TGFβ in patients with MIS-C can trigger EBV reactivation, which is reversible with TGFβ blockade. Clinically, the TGFβ-induced defect in T cell reactivity correlates with a higher EBV seroprevalence in patients with MIS-C compared with age-matched controls, along with the occurrence of EBV reactivation. Our findings establish a connection between SARS-CoV-2 infection and COVID-19 sequelae in children, in which impaired T cell cytotoxicity triggered by TGFβ overproduction leads to EBV reactivation and subsequent hyperinflammation. Multisystem inflammatory syndrome following SARS-CoV-2 infection results from increased serum levels of TGFβ, which impairs the reactivation of virus-specific T cells.
The goal of future quantum networks is to enable new internet applications that are impossible to achieve using only classical communication1–3. Up to now, demonstrations of quantum network applications4–6 and functionalities7–12 on quantum processors have been performed in ad hoc software that was specific to the experimental setup, programmed to perform one single task (the application experiment) directly into low-level control devices using expertise in experimental physics. Here we report on the design and implementation of an architecture capable of executing quantum network applications on quantum processors in platform-independent high-level software. We demonstrate the capability of the architecture to execute applications in high-level software by implementing it as a quantum network operating system—QNodeOS—and executing test programs, including a delegated computation from a client to a server13 on two quantum network nodes based on nitrogen-vacancy (NV) centres in diamond14,15. We show how our architecture allows us to maximize the use of quantum network hardware by multitasking different applications. Our architecture can be used to execute programs on any quantum processor platform corresponding to our system model, which we illustrate by demonstrating an extra driver for QNodeOS for a trapped-ion quantum network node based on a single 40Ca+ atom16. Our architecture lays the groundwork for computer science research in quantum network programming and paves the way for the development of software that can bring quantum network technology to society. A new quantum operating system architecture is described that is capable of executing applications on quantum networks in high-level software, which is a step towards bringing quantum network technology to society.
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 descended1. 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 signal1. 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. The root of the eukaryote Tree of Life is estimated from a new, larger dataset of mitochondrial proteins including all known eukaryotic supergroups, showing it lies between two multi-supergroup assemblages.
Two-dimensional (2D) metals are appealing for many emergent phenomena and have recently attracted research interests1–9. Unlike the widely studied 2D van der Waals (vdW) layered materials, 2D metals are extremely challenging to achieve, because they are thermodynamically unstable1,10. Here we develop a vdW squeezing method to realize diverse 2D metals (including Bi, Ga, In, Sn and Pb) at the ångström thickness limit. The achieved 2D metals are stabilized from a complete encapsulation between two MoS2 monolayers and present non-bonded interfaces, enabling access to their intrinsic properties. Transport and Raman measurements on monolayer Bi show excellent physical properties, for example, new phonon mode, enhanced electrical conductivity, notable field effect and large nonlinear Hall conductivity. Our work establishes an effective route for implementing 2D metals, alloys and other 2D non-vdW materials, potentially outlining a bright vision for a broad portfolio of emerging quantum, electronic and photonic devices. Melting and squeezing pure metals between two sapphires covered in molybdenum disulfide produces diverse two-dimensional metals at the ångström thickness limit.
Habitat fragmentation generally reduces biodiversity at the patch scale (α diversity)1. However, there is ongoing debate about whether such negative effects can be alleviated at the landscape scale (γ diversity) if among-patch diversity (β diversity) increases as a result of fragmentation2–6. This controversial view has not been rigorously tested. Here we use a dataset of 4,006 taxa across 37 studies from 6 continents to test the effects of fragmentation on biodiversity across scales by explicitly comparing continuous and fragmented landscapes. We find that fragmented landscapes consistently have both lower α diversity and lower γ diversity. Although fragmented landscapes did tend to have higher β diversity, this did not translate into higher γ diversity. Our findings refute claims that habitat fragmentation can increase biodiversity at landscape scales, and emphasize the need to restore habitat and increase connectivity to minimize biodiversity loss at ever-increasing scales. An analysis of habitat fragmentation using a dataset of more than 4,000 species worldwide shows that fragmentation reduces biodiversity at all scales, and that increases in β diversity do not compensate for the loss of α diversity.
Who the first inhabitants of Western Europe were, what their physical characteristics were, and when and where they lived are some of the pending questions in the study of the settlement of Eurasia during the Early Pleistocene epoch. The available palaeoanthropological information from Western Europe is limited and confined to the Iberian Peninsula1,2. Here we present most of the midface of a hominin found at the TE7 level of the Sima del Elefante site (Sierra de Atapuerca, Spain), dated to between 1.4 million and 1.1 million years ago. This fossil (ATE7-1) represents the earliest human face of Western Europe identified thus far. Most of the morphological features of the midface of this hominin are primitive for the Homo clade and they do not display the modern-like aspect exhibited by Homo antecessor found at the neighbouring Gran Dolina site, also in the Sierra de Atapuerca, and dated to between 900,000 and 800,000 years ago3. Furthermore, ATE7-1 is more derived in the nasoalveolar region than the Dmanisi and other roughly contemporaneous hominins. On the basis of the available evidence, it is reasonable to assign the new human remains from TE7 level to Homo aff. erectus. From the archaeological, palaeontological and palaeoanthropological information obtained in the lower levels of the Sima del Elefante and Gran Dolina sites4–8, we suggest a turnover in the human population in Europe at the end of the Early Pleistocene. A Homo aff. erectus individual dated to 1.4 million to 1.1 million years ago found at Sima del Elefante (Sierra de Atapuerca, Spain) does not display the modern-human-like aspect of Homo antecessor found at the neighbouring Gran Dolina site (900,000–800,000 years ago).
Active systems composed of energy-generating microscopic constituents are a promising platform to create autonomous functional materials1–16 that can, for example, locomote through complex and unpredictable environments. Yet coaxing these energy sources into useful mechanical work has proved challenging. Here we engineer active solids based on centimetre-scale building blocks that perform adaptive locomotion. These prototypes exhibit a non-variational form of elasticity characterized by odd moduli8,12,17, whose magnitude we predict from microscopics using coarse-grained theories and which we validate experimentally. When interacting with an external environment, these active solids spontaneously undergo limit cycles of shape changes, which naturally lead to locomotion such as rolling and crawling. The robustness of the locomotion is rooted in an emergent feedback loop between the active solid and the environment, which is mediated by elastic deformations and stresses. As a result, our active solids are able to accelerate, adjust their gaits and locomote through a variety of terrains with a similar performance to more complex control strategies implemented by neural networks. Our work establishes active solids as a bridge between materials and robots and suggests decentralized strategies to control the nonlinear dynamics of biological systems8,18–22, soft materials5,6,9,11,12,23–25 and driven nanomechanical devices7,26–30. The development of active solids based on centimetre-scale building blocks incorporating odd elasticity shows that they can spontaneously undergo limit cycles of shape changes, leading to adaptive locomotion such as rolling and crawling.
Global ocean surface temperatures were at record levels for more than a year from April 2023 onwards, exceeding the previous record in 2015–2016 by 0.25 °C on average between April 2023 and March 20241. The nearly global extent and unprecedented intensity of this event prompted questions about how exceptional it was and whether climate models can represent such record-shattering jumps in surface ocean temperatures2. Here we construct observation-based synthetic time series to show that a jump in global sea surface temperatures that breaks the previous record by at least 0.25 °C is a 1-in-512-year event under the current long-term warming trend (1-in-205-year to 1-in-1,185-year event; 95% confidence interval). Without a global warming trend, such an event would have been practically impossible. Using 270 simulations from a wide range of fully coupled climate models, we show that these models successfully simulate such record-shattering jumps in global ocean surface temperatures, underpinning the models’ usefulness in understanding the characteristics, drivers and consequences of such events. These model simulations suggest that the record-shattering jump in surface ocean temperatures in 2023–2024 was an extreme event after which surface ocean temperatures are expected to revert to the expected long-term warming trend. Observations and climate models suggest that the global sea surface temperature jump in 2023–2024 was not unexpected and would have been nearly impossible without anthropogenic warming.
Intratumour heterogeneity and phenotypic plasticity drive tumour progression and therapy resistance1,2. Oncogene dosage variation contributes to cell-state transitions and phenotypic heterogeneity3, thereby providing a substrate for somatic evolution. Nonetheless, the genetic mechanisms underlying phenotypic heterogeneity are still poorly understood. Here we show that extrachromosomal DNA (ecDNA) is a major source of high-level focal amplification in key oncogenes and a major contributor of MYC heterogeneity in pancreatic ductal adenocarcinoma (PDAC). We demonstrate that ecDNAs drive varying levels of MYC dosage, depending on their regulatory landscape, enabling cancer cells to rapidly and reversibly adapt to microenvironmental changes. In the absence of selective pressure, a high ecDNA copy number imposes a substantial fitness cost on PDAC cells. We also show that MYC dosage affects cell morphology and dependence of cancer cells on stromal niche factors. Our work provides a detailed analysis of ecDNAs in PDAC and describes a new genetic mechanism driving MYC heterogeneity in PDAC. In a model of pancreatic ductal adenocarcinoma, extrachromosomal DNAs are shown to be a source of high-level focal amplification driving MYC heterogeneity and phenotypic adaptation.
Many natural motor skills, such as speaking or locomotion, are acquired through a process of trial-and-error learning over the course of development. It has long been hypothesized, motivated by observations in artificial learning experiments, that dopamine has a crucial role in this process. Dopamine in the basal ganglia is thought to guide reward-based trial-and-error learning by encoding reward prediction errors1, decreasing after worse-than-predicted reward outcomes and increasing after better-than-predicted ones. Our previous work in adult zebra finches—in which we changed the perceived song quality with distorted auditory feedback—showed that dopamine in Area X, the singing-related basal ganglia, encodes performance prediction error: dopamine is suppressed after worse-than-predicted (distorted syllables) and activated after better-than-predicted (undistorted syllables) performance2. However, it remains unknown whether the learning of natural behaviours, such as developmental vocal learning, occurs through dopamine-based reinforcement. Here we tracked song learning trajectories in juvenile zebra finches and used fibre photometry3 to monitor concurrent dopamine activity in Area X. We found that dopamine was activated after syllable renditions that were closer to the eventual adult version of the song, compared with recent renditions, and suppressed after renditions that were further away. Furthermore, the relationship between dopamine and song fluctuations revealed that dopamine predicted the future evolution of song, suggesting that dopamine drives behaviour. Finally, dopamine activity was explained by the contrast between the quality of the current rendition and the recent history of renditions—consistent with dopamine’s hypothesized role in encoding prediction errors in an actor–critic reinforcement-learning model4,5. Reinforcement-learning algorithms6 have emerged as a powerful class of model to explain learning in reward-based laboratory tasks, as well as for driving autonomous learning in artificial intelligence7. Our results suggest that complex natural behaviours in biological systems can also be acquired through dopamine-mediated reinforcement learning. Studies in zebra finches show that dopamine has a key role as a reinforcement signal in the trial-and-error process of learning that underlies complex natural behaviours.
Mechanical metamaterials with high recoverable elastic energy density, which we refer to as high-enthalpy elastic metamaterials, can offer many enhanced properties, including efficient mechanical energy storage1,2, load-bearing capability, impact resistance and motion agility. These qualities make them ideal for lightweight, miniaturized and multi-functional structures3–8. However, achieving high enthalpy is challenging, as it requires combining conflicting properties: high stiffness, high strength and large recoverable strain9–11. Here, to address this challenge, we construct high-enthalpy elastic metamaterials from freely rotatable chiral metacells. Compared with existing non-chiral lattices, the non-optimized chiral metamaterials simultaneously maintain high stiffness, sustain larger recoverable strain, offer a wider buckling plateau, improve the buckling strength by 5–10 times, enhance enthalpy by 2–160 times and increase energy per mass by 2–32 times. These improvements arise from torsional buckling deformation that is triggered by chirality and is absent in conventional metamaterials. This deformation mode stores considerable additional energy while having a minimal impact on peak stresses that define material failure. Our findings identify a mechanism and provide insight into the design of metamaterials and structures with high mechanical energy storage capacity, a fundamental and general problem of broad engineering interest. High-enthalpy elastic metamaterials constructed from freely rotatable chiral metacells have high stiffness, large recoverable strain and improved buckling strength.
Nanoribbons, nanometre-wide strips of a two-dimensional material, are a unique system in condensed matter. They combine the exotic electronic structures of low-dimensional materials with an enhanced number of exposed edges, where phenomena including ultralong spin coherence times1,2, quantum confinement3 and topologically protected states4,5 can emerge. An exciting prospect for this material concept is the potential for both a tunable semiconducting electronic structure and magnetism along the nanoribbon edge, a key property for spin-based electronics such as (low-energy) non-volatile transistors6. Here we report the magnetic and semiconducting properties of phosphorene nanoribbons (PNRs). We demonstrate that at room temperature, films of PNRs show macroscopic magnetic properties arising from their edge, with internal fields of roughly 240 to 850 mT. In solution, a giant magnetic anisotropy enables the alignment of PNRs at sub-1-T fields. By leveraging this alignment effect, we discover that on photoexcitation, energy is rapidly funnelled to a state that is localized to the magnetic edge and coupled to a symmetry-forbidden edge phonon mode. Our results establish PNRs as a fascinating system for studying the interplay between magnetism and semiconducting ground states at room temperature and provide a stepping-stone towards using low-dimensional nanomaterials in quantum electronics. Phosphorene nanoribbons demonstrate extraordinary magnetic properties, ranging from large internal fields in films to macroscopic alignment in solution, which can be coupled to photoexcitations that localize to the magnetic edge of these ribbons.
Hepatic stellate cells (HSCs) have a central pathogenetic role in the development of liver fibrosis. However, their fibrosis-independent and homeostatic functions remain poorly understood1–5. Here we demonstrate that genetic depletion of HSCs changes WNT activity and zonation of hepatocytes, leading to marked alterations in liver regeneration, cytochrome P450 metabolism and injury. We identify R-spondin 3 (RSPO3), an HSC-enriched modulator of WNT signalling, as responsible for these hepatocyte-regulatory effects of HSCs. HSC-selective deletion of Rspo3 phenocopies the effects of HSC depletion on hepatocyte gene expression, zonation, liver size, regeneration and cytochrome P450-mediated detoxification, and exacerbates alcohol-associated and metabolic dysfunction-associated steatotic liver disease. RSPO3 expression decreases with HSC activation and is inversely associated with outcomes in patients with alcohol-associated and metabolic dysfunction-associated steatotic liver disease. These protective and hepatocyte-regulating functions of HSCs via RSPO3 resemble the R-spondin-expressing stromal niche in other organs and should be integrated into current therapeutic concepts. Hepatic stellate cells regulate hepatocyte functions via R-spondin 3.
Navigating social environments is a fundamental challenge for the brain. It has been established that the brain solves this problem, in part, by representing social information in an agent-centric manner; knowledge about others’ abilities or attitudes is tagged to individuals such as ‘oneself’ or the ‘other’1–6. This intuitive approach has informed the understanding of key nodes in the social parts of the brain, the dorsomedial prefrontal cortex (dmPFC) and the anterior cingulate cortex (ACC)7–9. However, the patterns or combinations in which individuals might interact with one another is as important as the identities of the individuals. Here, in four studies using functional magnetic resonance imaging, behavioural experiments and a social group decision-making task, we show that the dmPFC and ACC represent the combinatorial possibilities for social interaction afforded by a given situation, and that they do so in a compressed format resembling the basis functions used in spatial, visual and motor domains10–12. The basis functions align with social interaction types, as opposed to individual identities. Our results indicate that there are deep analogies between abstract neural coding schemes in the visual and motor domain and the construction of our sense of social identity. A study combining group decision-making tasks with fMRI shows that the brain’s dorsomedial prefrontal cortex uses basis functions, similar to those in the visual, motor and spatial domains, to represent patterns of social interaction.
Adenosine triphosphate (ATP) is the principal energy currency of all living cells1,2. Metabolically impaired obligate intracellular parasites, such as the human pathogens Chlamydia trachomatis and Rickettsia prowazekii, can acquire ATP from their host cells through a unique ATP/adenosine diphosphate (ADP) translocator, which mediates the import of ATP into and the export of ADP and phosphate out of the parasite cells, thus allowing the exploitation of the energy reserves of host cells (also known as energy parasitism). This type of ATP/ADP translocator also exists in the obligate intracellular endosymbionts of protists and the plastids of plants and algae and has been implicated to play an important role in endosymbiosis3–31. The plastid/parasite type of ATP/ADP translocator is phylogenetically and functionally distinct from the mitochondrial ATP/ADP translocator, and its structure and transport mechanism are still unknown. Here we report the cryo-electron microscopy structures of two plastid/parasite types of ATP/ADP translocators in the apo and substrate-bound states. The ATP/ADP-binding pocket is located at the interface between the N and C domains of the translocator, and a conserved asparagine residue within the pocket is critical for substrate specificity. The translocator operates through a rocker-switch alternating access mechanism involving the relative rotation of the two domains as rigid bodies. Our results provide critical insights for understanding ATP translocation across membranes in energy parasitism and endosymbiosis and offer a structural basis for developing drugs against obligate intracellular parasites. ATP/ADP translocators in obligate intracellular parasites and plastids facilitate energy parasitism and endosymbiosis by mediating ATP import and ADP export, with their cryo-EM structures and mechanisms revealed, providing insights for drug development against intracellular pathogens.
Given the high recurrence rates of hepatocellular carcinoma (HCC) post-resection1–3, improved early identification of patients at high risk for post-resection recurrence would help to improve patient outcomes and prioritize healthcare resources4–6. 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. A publicly accessible tool—the TIMES score—for predicting the risk of recurrence of hepatocellular carcinoma is revealed, providing mechanistic insights into the prognostic patterns for hepatocellular carcinoma.
Climate change is expected to increase heavy rainfall with concomitant increases in flooding1. Causes of increased heavy rainfall include the higher water-holding capacity of a warmer atmosphere and changes in atmospheric circulation patterns2, which may translate into future heavy rainfall increases in most of Europe3. However, gathering evidence on the time evolution of past changes has been hampered by data limitations and measurement uncertainties, in particular for short rainfall durations, such as 1 h. Here we show an 8% increase in daily and 15% increase in hourly heavy rainfall over the last four decades by analysing a new dataset comprising 883 stations in Austria from 1900 to 2023. These increases are fully consistent between two independent networks and occurred after a retarding phase between 1960 and 1980. Hourly heavy rainfall changes are aligned with temperature increases with the sensitivity of a 7% increase per 1 °C of warming, in line with Clausius–Clapeyron scaling. Daily heavy rainfall changes, however, are aligned with atmospheric circulation indices with little correlation to air temperature, which suggests a bigger role of atmospheric circulation modes than previously thought. The daily heavy rainfall changes are remarkably consistent with observed flood increases of about 8% in large catchments. The hourly heavy rainfall changes are similarly consistent with flood changes in small catchments, although the flood increase is stronger (25% over the last four decades). Climate adaptation measures in flood management may therefore be more pressing for rivers draining smaller catchment areas than for large rivers. Long-term increases in heavy daily and hourly precipitation in Austria from different climatic mechanisms emphasize the need for flood management adaptation, especially in smaller catchments affected by the increased hourly rainfall.
Magnonic systems provide a fertile playground for bosonic topology1, for example, Dirac2–6 and Weyl7,8 magnons, leading to a variety of exotic phenomena such as charge-free topologically protected boundary modes6,7, the magnon thermal Hall effect9 and the magnon spin Nernst effect10. However, their understanding has been hindered by the absence of fundamental symmetry descriptions of magnetic geometries and spin Hamiltonians primarily governed by isotropic Heisenberg interactions. The ensuing magnon dispersions enable gapless magnon band nodes that go beyond the scenario of representation theory of the magnetic space groups11,12, thus referred to as unconventional magnons. Here we developed spin space group13–17 theory to elucidate collinear magnetic configurations, classifying the 1,421 collinear spin space groups into 4 types, constructing their band representations and providing a comprehensive tabulation of unconventional magnons, such as duodecuple points, octuple nodal lines and charge-4 octuple points. On the basis of the MAGNDATA database18, we identified 498 collinear magnets with unconventional magnons, among which more than 200 magnon band structures were obtained by using first-principles calculations and linear spin wave theory. In addition, we evaluated the influence of the spin–orbit-coupling-induced exchange interaction in these magnets and found that more than 80 per cent are predominantly governed by the Heisenberg interactions, indicating that the spin space group serves as an ideal framework for describing magnon band nodes in most 3d, 4d and half-filled 4f collinear magnets. Spin space group theory is applied to identify more than 200 collinear magnets with unconventional magnons; high-throughput calculations with spin–orbit coupling find that most of these unconventional magnets are dictated by the Heisenberg exchange interaction.
Ancient DNA from the Mediterranean region has revealed long-range connections and population transformations associated with the spread of food-producing economies1–6. However, in contrast to Europe, genetic data from this key transition in northern Africa are limited, and have only been available from the far western Maghreb (Morocco)1–3. Here we present genome-wide data for nine individuals from the Later Stone Age through the Neolithic period from Algeria and Tunisia. The earliest individuals cluster with pre-Neolithic people of the western Maghreb (around 15,000–7,600 years before present (bp)), showing that this ‘Maghrebi’ ancestry profile had a substantial geographic and temporal extent. At least one individual from Djebba (Tunisia), dating to around 8,000 years bp, harboured ancestry from European hunter–gatherers, probably reflecting movement in the Early Holocene across the Strait of Sicily. Later Neolithic people from the eastern Maghreb retained largely local forager ancestry, together with smaller contributions from European farmers (by around 7,000 years bp) and Levantine groups (by around 6,800 years bp), and were thus far less impacted by external gene flow than were populations in other parts of the Neolithic Mediterranean. Ancient DNA from the eastern Maghreb (Tunisia and Algeria) dating between 15,000 and 6,000 years ago shows that this region was far less affected by external gene flow than the rest of the Neolithic Mediterranean, including not only Europe but also the western Maghreb (Morocco).
Frictional interfaces are found in systems ranging from biological joints to earthquake faults. When and how these interfaces slide is a fundamental problem in geosciences and engineering1–20. It is believed that there exists a threshold shear force, called static friction, below which the interface is stationary4,10, despite many studies suggesting that this concept is outdated1,21–28. By contrast, rate-and-state friction formulations1,26,27 predict that interfaces are always sliding29, but this feature is often considered an artefact that calls for modifications30. Here we show that nominally stationary interfaces subjected to constant shear and normal loads, with a driving force that is notably below the classically defined static friction for which creep is known to occur9,27–29, are sliding, but with diminishingly small rates down to 10−12 m s−1. Our precise measurements directly at the interface are enabled by digital image correlation18,31,32. This behaviour contradicts classical models of friction but confirms the prediction of rate-and-state friction1,26,27. The diminishing slip rates of nominally stationary interfaces reflect interface healing, which would manifest itself in higher peak friction in subsequent slip events15,27,33, such as earthquakes and landslides, substantially modifying their nucleation and propagation and hence their hazard3,12,13,34. Digital image correlation measurements show that nominally stationary interfaces subjected to constant shear and normal loads are sliding at extremely small rates, confirming the predictions of rate-and-state friction formulations.
Although learning in response to extrinsic reinforcement is theorized to be driven by dopamine signals that encode the difference between expected and experienced rewards1,2, skills that enable verbal or musical expression can be learned without extrinsic reinforcement. Instead, spontaneous execution of these skills is thought to be intrinsically reinforcing3,4. Whether dopamine signals similarly guide learning of these intrinsically reinforced behaviours is unknown. In juvenile zebra finches learning from an adult tutor, dopamine signalling in a song-specialized basal ganglia region is required for successful song copying, a spontaneous, intrinsically reinforced process5. Here we show that dopamine dynamics in the song basal ganglia faithfully track the learned quality of juvenile song performance on a rendition-by-rendition basis. Furthermore, dopamine release in the basal ganglia is driven not only by inputs from midbrain dopamine neurons classically associated with reinforcement learning but also by song premotor inputs, which act by means of local cholinergic signalling to elevate dopamine during singing. Although both cholinergic and dopaminergic signalling are necessary for juvenile song learning, only dopamine tracks the learned quality of song performance. Therefore, dopamine dynamics in the basal ganglia encode performance quality during self-directed, long-term learning of natural behaviours. Dopamine release in the basal ganglia of the zebra finch is driven by neurons associated with reinforcement learning and by cholinergic signalling, and tracks performance quality during long-term learning of its song.
Optical amplification, crucial for modern communication, primarily relies on erbium-doped fibre amplifiers (EDFAs)1,2. Yet, EDFAs only cover a portion of the low-loss spectrum of optical fibres. This has motivated the development of amplifiers operating beyond the erbium gain window. Pioneering work on optical parametric amplifiers (OPAs)3,4 using intrinsic third-order optical nonlinearity has led to demonstrations of increased channel capacity. OPAs offer high gain, can reach the 3-dB quantum limit for phase-preserving amplifiers and exhibit unidirectional operation. However, power requirements for highly nonlinear fibres3,5–8 or bulk waveguides9,10 have impeded their adoption. By contrast, OPAs based on integrated photonic circuits offer the advantages of substantially increased mode confinement and optical nonlinearity but have been limited in bandwidth11,12. We overcome this challenge by using low-loss gallium phosphide-on-silicon dioxide13–15 photonic integrated circuits (PICs) and attain up to 35 dB of parametric gain with waveguides only a few centimetres long in a compact footprint of 0.25 square millimetres. Fibre-to-fibre net gain exceeding 10 dB across an ultra-broad bandwidth of approximately 140 nm (that is, 17 THz) is achieved, with a threefold increase in the gain window compared with C-band EDFAs. We further demonstrate a high dynamic range for input signals, spanning six orders of magnitude, while maintaining a low noise figure. We exploit these performance characteristics to amplify coherent communication signals. This marks, to our knowledge, the first ultra-broadband, high-gain, continuous-wave amplification in a photonic chip, opening up new capabilities for next-generation integrated photonics. An optical parametric amplifier based on integrated photonic circuits fabricated using low-loss gallium phosphide-on-silicon dioxide demonstrates improved bandwidth and gain performance over state-of-the-art erbium-doped fibre amplifiers while maintaining a low noise figure.
Immune cells called natural killer cells can target and eliminate tumours. The gene expression and spatial distribution of the immune cells in the tumour microenvironment indicates whether liver cancer will recur after surgery. Immune cells called natural killer cells can target and eliminate tumours. The gene expression and spatial distribution of the immune cells in the tumour microenvironment indicates whether liver cancer will recur after surgery.
The partial midface of a hominin fossil has been found in the Sima del Elefante cave site near Burgos, northern Spain, and dates to between 1.4 million and 1.1 million years ago. Its discovery enables the exploration of the facial features of early Europeans and enhances our understanding of the evolutionary history of European ancestors. Fossilized midface is thought to be from a hominin species not previously found in Europe.
William Mills aims to make the website for his laboratory more than just a channel for promoting publications and research projects to the outside world. William Mills aims to make the website for his laboratory more than just a channel for promoting publications and research projects to the outside world.
Tiny anvil squeezes metal atoms into super-thin sheets with strange properties. Tiny anvil squeezes metal atoms into super-thin sheets with strange properties.
The immune molecule TGFβ has been found to weaken immune defences against latent viruses, triggering reactivation of the Epstein–Barr virus. This mechanism links TGFβ release in SARS-CoV-2 infection to multisystem inflammatory syndrome in children, and could inform the development of therapies for managing this serious condition. The molecule TGFβ suppresses the ability of T cells to protect against latent Epstein–Barr virus.
The biologist’s theories about how environments prompt rapid species evolution and extinction propelled her onto the world stage. The biologist’s theories about how environments prompt rapid species evolution and extinction propelled her onto the world stage.
The human brain not only remembers who other people are, it also uses basic mathematical functions called basis functions to store information about how people interact — for example, how they work together or compete. Each basis function specifies part of an interaction pattern, and combinations of them specify complex interactions. A brain region called the medial prefrontal cortex encodes patterns of social interactions as combinations of mathematical functions.
Quantum computers have gained the powerful abstractions that allow programmers of classical computers to design and integrate new apps and hardware, and connect devices into networks with ease. An operating system for quantum computers allows for easy app networking.
Roughly 8,000-year-old remains unearthed from present-day Tunisia held a surprise: European hunter-gatherer ancestry. Roughly 8,000-year-old remains unearthed from present-day Tunisia held a surprise: European hunter-gatherer ancestry.
A global analysis of species in fragmented-forest landscapes reveals species losses in fragments, and that the changes in species composition across fragments is not enough to benefit biodiversity over entire landscapes. Assessing the effect of forest fragmentation on biodiversity.
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