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AI will reorganize science. Will research remain a human enterprise?
Identification of carnivory in the flowering plant Saxifraga via multidisciplinary evidence
Abstract The transformation from prey to predator is a striking adaptive innovation shared by all carnivorous plants, which capture and digest diverse animal prey for nutrients (nitrogen, N). Here, we report carnivory in the alpine flowering plant Saxifraga candelabrum (Saxifragaceae; Saxifragales). Field experiments and herbarium surveys reveal that this plant actively attracts and captures insect prey via glandular hairs. Enzymatic analyses further confirm the ability of plants to digest prey, and isotope labelling experiments using ¹⁵N-labelled insects demonstrate the transfer of nitrogen from prey to plant tissues, thus verifying the presence of carnivory. Genomic comparisons reveal a significant genome-wide convergence in genes related to carnivory (e.g., leaf morphogenesis, digestion and nutrition) across six independent origins of carnivory in diverse flowering plant lineages. Our findings provide definitive evidence of carnivory in Saxifraga , addressing Charles Darwin’s long-standing hypothesis that some Saxifraga species may be capable of carnivory, and further suggest that carnivory may be more widespread among angiosperms than previously recognized.
RelB NF-κB tunes Notch2 signaling to promote IL-23-secreting solitary isolated lymphoid tissue–resident DCs critical for gut immunity
While preserving tolerance toward commensals, dendritic cells (DCs) also orchestrate response against pathogens. The noncanonical RelB NF-κB pathway in DCs curbs tolerogenic Tregs in the intestine. Whether RelB-dependent DC regulations also impact intestinal immunity remains less clear. Here, we show that genetic ablation of RelB in DCs compromises IL-23-dependent immune response in the intestine, imparting vulnerability in Relb ΔCD11c mice to infection with Citrobacter rodentium , an enteropathogen. Our mechanistic studies revealed that RelB supported the expression of RBP-J from a κB site-driven promoter, tuning Notch2 response in DCs. This RelB-mediated Notch2 control specified a solitary isolated lymphoid tissue–resident DC subset, which served as a dominant source of IL-23 in infected mice. Indeed, we found that IL-23 supplementation readily rescued the immune deficiency of Relb ΔCD11c mice, improving bacterial clearance. In sum, we illustrate a previously unrecognized crosstalk between RelB and Notch2 underpinning IL-23-secreting DCs critical for gut immunity.
Translational control by RPL22L1-specific ribosomes enhances DNA repair and chemoresistance
Profile of Morris Moscovitch
Morris Moscovitch’s five-decade career has reshaped scientists’ understanding of how the brain stores and retrieves memories. His Multiple Trace Theory challenged the view that the hippocampus serves only as temporary storage, showing instead that richly detailed episodic memories remain dependent on the hippocampus indefinitely. Moscovitch demonstrated that the hippocampus contributes not just to remembering but to imagination, problem-solving, and social cognition. His recent work reveals that people detect episodic richness in others’ memories and use this signal to guide social preferences. Through collaborative research spanning hemispheric specialization and face recognition, Moscovitch has revealed memory as central to human cognition.
Biomimetic diffusion metamaterials enabled by physical-geometric duality
Comparative archaeology reveals recurrent but nondeterministic pathways through complexification
The amount of variation observed among early complex societies has challenged efforts to understand their social dynamics. We advocate for a comparative approach that directly investigates the forces producing this variation. By holistically ranking 63 trajectories of societal change along five axes of differentiation, we characterize their development from a multidimensional perspective. Our analysis reveals that the majority of these trajectories align with one of six recurrent pathways through “complexification,” identified from broadly similar courses of development shared across multiple trajectories. These patterns provide a framework for understanding the conditions under which different forms of complexity emerged—or failed to do so. Particular attention is paid to the ways in which social and demographic forces interact along these pathways. Crucially, these forces interact probabilistically rather than deterministically, producing widespread tendencies rather than inevitable outcomes. Focusing future research on mediating and confounding variables, expanding the sample of trajectories available for analysis, identifying additional complexification pathways and the social forces at work in them, and leveraging the explanatory potential of trajectories that do not align well with any developmental pattern, will further enrich our understanding of the complexification process.
Coupled air–sea interactions drove and sustained the 2013–2016 North Pacific marine heatwave
Abstract The 2013–2016 marine heatwave (MHW) in the Northeastern Pacific ranks among the most intense extratropical ocean warming events on record. Its intricate evolution has complicated efforts to understand the underlying dynamics crucial for predicting future MHWs. Here, we track the MHW using a closed, three-dimensional Lagrangian heat budget that quantifies the processes driving its evolution. Three-dimensional particle trajectories separate the MHW into northern and southern components and reveal that they are of distinct kinematic origin. We quantitatively demonstrate through a closed budget that advection, rather than surface forcing, plays the dominant role in sustaining the MHW’s heat content. The northern component was maintained by a weakening of Ekman heat transport across the North Pacific Current, combined with reduced wintertime surface heat loss. The southern component was driven by weakened Ekman upwelling caused by reduced alongshore winds over the California Current. We further identify a persistent low sea-level pressure anomaly over the central Pacific that altered wind patterns, redistributing heat and moisture poleward to ultimately force both parts of the MHW. Elevated surface temperatures, in turn, amplified this pressure anomaly, completing a positive feedback loop that sustained the event across multiple years.
An expanded apolipoprotein D family provides spider mites with dual-layer protection against dietary oxidative stress
Plant defense has driven the evolution of species-dependent adaptive strategies in many herbivores, but the molecular mechanisms of adaptation in most arthropods remain largely unknown. The two-spotted spider mite ( Tetranychus urticae ) is a generalist herbivore that feeds by sucking the contents of mesophyll cells, a feeding strategy distinct from that of phloem-feeding insects. Here, we show the unexpected differential expression of apolipoprotein D ( ApoD ) genes during feeding when mites are transferred to different host plant species, as well as extreme gene family expansion (64 ApoD paralogs, the largest reported in any organism). We find that ApoD proteins protect mites against reactive oxygen species (ROS) during feeding, and we identify a dual-layer mechanism by which ApoD proteins counteract plant ROS defenses during ingestion and digestion. First, the salivary protein TuApoD2 is secreted during the ingestion of mesophyll cell contents, where it interacts with glycolate oxidase 2 (GOX2) to inhibit H 2 O 2 generation. After ingestion, TuApoD33 in the gut cells also interacts with GOX2 to maintain the inhibition of H 2 O 2 generation. These findings suggest that the evolutionary expansion of the ApoD gene family is a key component of the molecular arms race between herbivorous mites and host plants.
In vivo CRISPR screening identifies metastasis suppressors in triple-negative breast cancer
Mitochondrial pearling is controlled by the inner membrane and mediates segregation of the luminal content and membrane scission
Membrane pearling, the transformation of a smooth tubule into a chain of bead-like swellings connected by narrow membrane tethers, is a widely observed shape change. While it has been well studied for synthetic lipid and unilamellar intracellular membranes, the mechanism underlying the pearling of the peculiar double-membrane architecture of tubular mitochondria remained elusive. Here, we addressed the role of the strongly convoluted inner mitochondrial membrane (IMM) in pearling driven by stretching. Using a light-gated, mitochondria-specific mechanostimulator to apply stretching forces to mitochondria in live cells, we demonstrated that stretching triggers pearling of whole tubular mitochondria. Moreover, we found that pearling requires the presence of the IMM, as unilamellar tubules derived solely from the mitochondrial outer membrane elongate uniformly under stretching and never undergo pearling. To understand the physical mechanism by which IMM controls pearling, we developed a theoretical model that considers the lumen, effectively spanned and volumetrically stiffened by cristae, as an elastic continuum. Our computations show that pearling requires the luminal volume to be sufficiently resistant to change, with its effective bulk rigidity modulus exceeding a critical value. Our experimental observations further revealed the functionally important consequences of stretching-induced pearling. mtDNA nucleoids partitioned into the bulges of pearled configurations, suggesting a role for pearling in the reorganization of luminal components. In addition, the membrane fission GTPase DRP1 accumulated at the constrictions of pearled shapes, leading to membrane scission and mitochondrial fragmentation. Our work uncovers the unique biophysical mechanism of mitochondrial pearling and its functional significance for organelle dynamics.
Anisotropy-mediated stress regulation in Mn-substituted VOPO4 enables aqueous zinc batteries with long cycle life
Depletion-induced interactions modulate nanoscale protein diffusion in polymeric crowder solutions
Macromolecular crowding plays a crucial role in modulating protein dynamics in cellular and in vitro environments. Polymeric crowders such as dextran and Ficoll are known to induce entropic forces, including depletion interactions, that promote structural organization, yet their nanoscale consequences for protein dynamics remain poorly understood. Here, we employ megahertz X-ray photon correlation spectroscopy (MHz-XPCS) at the European X-ray Free Electron Laser (XFEL) to probe the dynamics of the protein ferritin in solutions containing sucrose, dextran, and Ficoll. We find pronounced changes in collective protein dynamics in polymeric crowders, revealing depletion-driven short-range attractions that, combined with long-range repulsions, give rise to intermediate-range organization. These mesoscale correlations undergo collective relaxation on microsecond to millisecond timescales, as directly resolved by XPCS through the decay of ferritin density fluctuations. The magnitude of this depends sensitively on crowder molecular weight and type. Normalizing the crowder concentration by c * reveals scaling behavior of ferritin self-diffusion with a crossover near 2 c *, marking a transition from depletion-enhanced mobility to viscosity-dominated slowing. Our results demonstrate that bulk properties alone are insufficient to describe protein dynamics in crowded solutions, highlighting the need to include polymer-specific interactions and depletion theory in models of crowded environments.
Multifunctional metal-organic frameworks for direct photosynthesis of cyclic carbonates from gaseous olefins
Developmental changes in memory structure and precision alter the use of retrieved episodes during decisions for reward
Most widely studied option evaluation strategies rely on knowledge accumulated across repeated experiences. But how should options be evaluated in unfamiliar environments, in which knowledge is sparse? In these situations, how do decision makers make efficient use of limited past experience to guide their choices? One possible strategy is episodic sampling, in which a decision maker retrieves a small number of past decisions from memory to estimate the value of present options. By virtue of their age, children and adolescents have less experience than adults, making episodic sampling a particularly useful strategy for them. At the same time, the effectiveness of episodic sampling derives from memory’s precision and context sensitivity—properties that continue to develop into adolescence and young adulthood. This tension raises a key question: are developmental differences in episodic memory associated with differences in episodic sampling? To address this question, 106 participants, ages 8 to 25, completed a 2-d choice task that dissociated the influence of a single episodic memory from the influence of multiple episodes sharing a common context. At all ages, single episodes biased choices. But, only adults were sensitive to the broader evoked context. Further clarifying the relationship between episodic memory and decision making, differences in memory precision predicted differences in episodic sampling, even after taking into account age, while episodic sampling, in turn, accounted for individual differences in forward planning. Together, these findings suggest that episodic memory guides decision making throughout development, but the character of its influence evolves as memory becomes more precise and richly structured.
Positional grammar of transcription factor binding partitions developmental and stress-response regulation in plants
The floral illusion: A parasitic beetle mimics the scent of flowers to attract bees
Animals are not known to biosynthesize floral chemical signals to manipulate pollinators, although such mimicry could profoundly shape plant–pollinator interactions. Larvae of the poisonous European blister beetle Meloe proscarabaeus parasitize multiple solitary bee species, yet the mechanism enabling host attraction has remained unresolved. Here we show that these larvae lure bees by emitting a bouquet of volatile compounds that closely resembles floral scent. Chemical analyses reveal a complex blend of monoterpenoids derived from ( S )-linalool, a ubiquitous floral volatile. Behavioral assays demonstrate that these compounds function as floral-scent mimics, eliciting attraction in bees and acting as allomones (i.e., interspecific chemical signals that benefit the emitter while disadvantaging the receiver). Transcriptomic and functional analyses identify cytochrome P450 enzymes that oxidize ( S )-linalool, suggesting that larvae biosynthesize these plant-like volatiles de novo. Together, these findings broaden the scope of interkingdom chemical mimicry and uncover a striking form of sensory deception in which an insect chemically assumes the signal identity of a flower, revealing that animals can evolve biosynthetic pathways to exploit plant–pollinator communication.
Vestibular nucleus stimulation for ameliorating locomotor dynamics in a Parkinsonian mouse model
Abstract Postural and locomotor dysfunction represent axial symptoms of Parkinson’s disease (PD), which remain poorly treated by medication and deep brain stimulation. Whilst non-invasive neuromodulation of the vestibular system via the vestibular nucleus complex (VNC) offers a novel therapeutic avenue, the underlying circuits are still poorly characterized. Here we show that the mouse VNC feeds extensive Vglut2 -defined projections into striato-thalamo-subthalamic and caudal medulla motor hubs and receives substantial input from the sensorimotor cortex. Optogenetic activation of excitatory VNC neurons at sub-symptomatic intensities increased cFos -based activity in basal ganglia-associated and brainstem motor targets. Unbiased pose dynamics and motion analysis respectively showed enhancement of behavioural modularity and locomotion with threshold-level stimulation. In a mouse model of PD, the latter further favored naturalistic gait patterns through improved motor coordination. Our data identify excitatory VNC processes as candidates for therapeutic targeting of axial motor dysfunction in the context of PD.
Long-horizon associative learning as a unifying framework for statistical learning across scales
Sensory inputs are rich with temporal patterns that unfold across multiple timescales. Uncovering these regularities is essential for anticipating future events and navigating the environment efficiently. Numerous models have been proposed to account for learning at specific temporal scales; however, they are often designed in isolation and rely on narrowly tuned statistical measures, limiting their generalizability to other paradigms. In contrast, humans typically learn without prior knowledge of the underlying structure or the relevant timescale at which regularities occur. Here, we present a unifying account of statistical learning that spans a wide range of temporal dependencies, from adjacent and nonadjacent transitions to complex network structures. This model, long-horizon associative learning, offers a biologically grounded implementation of the successor representation, or equivalently, the free energy minimization model. Reanalyzing data from 11 previously published studies, we show that a single neural mechanism captures both local statistical regularities and higher-order structural properties. This mechanism rests on graded temporal overlap of associative traces and is governed by a single free parameter (β). This initial domain-general associative learning process, emerging from the graded structure of associations, may later scaffold to higher-level operations such as grouping, categorization, rule abstraction, and memory formation. Overall, this framework offers a conceptual synthesis that bridges disparate strands of the statistical learning literature and reframes apparent paradigm-specific effects as different expressions of a common underlying computation.