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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.

Spatial and mechanistic elucidation of distance tunable Ru dual atom catalysts for efficient CO hydrogenation to ethanol

An antibody–drug conjugate active against antibiotic-resistant <i> <i>Neisseria</i> gonorrhoeae </i>

Neisseria gonorrhoeae is the causative agent of gonorrhea, a sexually transmitted infection which is rising in incidence, with increasing drug-resistant strains posing a significant public health threat. To address the urgent need for novel therapies, we developed an antibody–drug conjugate (ADC) that targets this important human pathogen. We utilized Tridecaptin A 1, a potent antimicrobial peptide (AMP) against Gram-negative bacteria that exhibits significant toxicity against human cells, limiting its development for clinical use. By conjugating the Tridecaptin A 1 analogue, Oct-TriA 1 to a monoclonal antibody (mAb) that specifically targets gonococcal MtrE, the outer membrane component of a drug efflux pump that is upregulated in resistant strains, we aim to selectively deliver the AMP to the gonococcus. However, Oct-TriA 1 was not bactericidal when directly conjugated to mAb. To circumvent this, we exploited an immune evasion mechanism employed by the gonococcus by introducing a linker between Oct-TriA 1 and the mAb which is specifically cleaved by the IgA protease (IgAP) secreted by the gonococcus; the IgAP inactivates human IgA. This ADC has no detectable toxicity for relevant human cells, kills the gonococcus in an MtrE- and IgAP-dependent manner, and is active against a strain which is resistant to first line agents. This modular ADC platform could be extended to other bacterial pathogens which employ proteases to evade immune killing, offering a strategy in the fight against antimicrobial resistance.

Trimeric autotransporter adhesins driving chain-like adhesion diversify surface colonization strategies in Shiga toxin-producing Escherichia coli

Abstract Bacteria frequently colonize host and environmental surfaces under fluid flow. Chain-like adherence pattern (CLAP) is an EibG-mediated surface colonization phenotype of certain Shiga toxin-producing Escherichia coli (STEC) that lack the locus of enterocyte effacement (LEE). EibG, an immunoglobulin-binding trimeric autotransporter adhesin, drives CLAP, but the temporal dynamics and genetic diversity underlying chain formation remain unclear. Here, we use live-cell time-lapse imaging to show that chains arise from single cells that elongate and divide without separation. Under flow, chains resist detachment and undergo shear-dependent fragmentation at cell-cell junctions, releasing viable clonal units that disperse downstream. Comparative genomics reveals diversity among EibG-related adhesins and identifies distinct lineages, including chain-like adhesins (Cla) that mediate CLAP while lacking IgG binding. Screening of 1,354 genomes from England shows that claB is present in 95.6% of strains from major LEE-negative STEC serotypes, highlighting its epidemiological prevalence. Targeted mutagenesis demonstrates that chain formation and IgG binding are mediated by distinct structural domains, revealing the modular functional architecture of these adhesins. Furthermore, we show that EibG, ClaA, and ClaB confer robust resistance to complement-mediated killing. Collectively, these findings establish CLAP as a dynamic, surface-associated strategy of LEE-negative STEC and reveal diversification among adhesins that drive this behavior.

Balanced polymorphism in a floral transcription factor underlies the ancient rhythm of daily sex alternation in avocado

In avocado and certain wild relatives in Lauraceae, a highly synchronized daily rhythm of floral sex timing promotes cross-pollination between two hermaphroditic flowering types. A-type plants present female-phase flowers in the morning and male-phase flowers in the afternoon, while B-types show the complementary pattern—a form of heterodichogamy. We mapped this dimorphism to a pair of dominant and recessive haplotypes at SDMYB , which belongs to a subgroup of R2R3 MYB transcription factors established as key regulators of floral maturation with links to circadian hormone signaling. Rhythmic diel SDMYB expression is associated with biphasic floral anthesis, and the dominant allele, which contains nonsynonymous changes in conserved functional domains, exhibits a cis -regulated phase delay, corresponding to the delayed second anthesis of A-type flowers. The SDMYB haplotypes form an ancient trans-species polymorphism, maintained by negative frequency-dependent balancing selection over 42 My, and they segregate in at least 26 nonavocado species, including in a genus where this mating system has not been reported. Although exceptionally old, the polymorphism is absent in other magnoliids with highly similar mating systems, suggesting daily forms of heterodichogamy can convergently evolve when rhythmic floral movements are coupled with the temporal separation of sexes.

The recent enhancement of the surface melt over the Antarctic Peninsula dictated by thermodynamics

Structures of the sodium-coupled phosphate importer SLC34A2 reveal a distinct architecture and gating mechanism

Dysregulation of inorganic phosphate (Pi) homeostasis contributes to metabolic disease, cancer, pathological calcification, and kidney disease. Systemic phosphate balance is regulated by SLC34 transporters that mediate renal Pi retention (SLC34A1/A3) and intestinal dietary Pi absorption (SLC34A2). SLC34s couple Pi uptake to the symport of sodium (Na + ) down its electrochemical gradient. Mutations or altered expression of SLC34 proteins are linked to disorders such as chronic kidney disease, where hyperphosphatemia is a major complication, and the lung disease pulmonary alveolar microlithiasis, caused by inactivating SLC34A2 mutations. SLC34A2 is also overexpressed in most ovarian and uterine tumors, making it an attractive target for antibody–drug conjugates. We present cryoelectron microscopy structures of SLC34A2 when the transporter is empty, bound to Na + ions only, fully loaded with Na + ions and Pi, and bound to an inhibitor phosphonoformic acid, revealing its distinct architecture, substrate and ion binding sites, the role of Na + , and multiple transporter states. Pi binds at a highly symmetric, membrane-embedded pocket positioned approximately mid-membrane and is coordinated by its signature four residue QSSS repeat motifs. Na + shapes the Pi-binding pocket and drives the transition from the outward-open to occluded state. Integrated with functional analyses, these structures reveal that SLC34 transporters operate through an atypical alternating access cycle defined by coordinated elevator movements of an auxiliary gate domain. This work lays a foundational framework for understanding Pi regulation and opens avenues for therapeutic strategies targeting disorders linked to phosphate imbalance.

A second yearly booster dose of the VLA15 Lyme borreliosis vaccine candidate in healthy individuals

Parenthood decisions in uncertain times: Experimental evidence from four countries

Fertility rates are declining across much of the globe, yet the forces driving this decline have become increasingly complex, and classic theories have become less adequate to explain recent trends. While economic and gender-related explanations have long dominated fertility research, emerging global uncertainties, such as climate change, democratic backsliding, economic crises, and regional conflicts, may also shape how individuals evaluate childbearing. In addition to the more classical factors, this cross-national study examines how macrolevel uncertainties influence perceptions of fertility intentions in Italy, Argentina, the United States, and Germany. These countries offer distinct fertility trajectories and face unique combinations of sociopolitical and environmental challenges. Using a conjoint experiment, we examine how individuals evaluate, across hypothetical scenarios, their intention of having a child under varying household, policy, and macrolevel conditions. Across all four countries, material security remains central: household income is the strongest predictor of fertility intentions, with homeownership and childcare playing smaller roles. At the same time, perceptions of macrolevel stability, including expectations about climate conditions, economic prospects, democratic functioning, and peace, exert substantial and meaningful effects, comparable to homeownership and childcare provision but more pronounced than those associated with gender-role arrangements. Cross-country differences show that macroeconomic stability and climate change are most consequential in Argentina, while in the United States respondents are less responsive to geopolitical conflict. These findings show that individuals evaluate childbearing not only through their immediate circumstances, but also through expectations about broader societal futures, highlighting the importance of incorporating macrolevel uncertainty when explaining contemporary fertility decline.

Publisher Correction: CFTR mediates Cl- transport in osteocytes to sustain cell viability and skeletal homeostasis

Treating language contact as normal: Coalescent-theoretic modeling of the prehistory of the Bantu language family

The Bantu language family of sub-Saharan Africa is among the largest in the world by the number of languages, by geographical extent, and by the number of speakers. The expansion of the Bantu languages is an important example of large-scale language-family expansions in the history of humankind. To learn the early prehistory of the Bantu language family, one needs to disentangle the signal of the original splits and diversification from that of the subsequent language contact, known to be strong in the Bantu languages. We introduce a coalescent-theoretic model to computationally study the prehistory of the Bantu family. Our model treats language contact as a norm rather than a rare exception, in contrast to earlier computational work. Applying Approximate Bayesian Computation, we show the rates of both language change and language contact to have been so high within the Bantu family that the signal of the original diversification has been largely erased in the currently available Bantu lexical data.

Interfacial chemistry governs nanoparticle self-sorting during biomimetic crystallization

Abstract Biominerals comprise composite crystals in which organic constituents are spatially organized within mineral matrices with exquisite precision, giving rise to hierarchically ordered architectures. Despite extensive efforts, achieving precise control over organic–inorganic interactions to construct biomimetic composite materials with programmable composition and spatial organization remains a major challenge. Here we show that diblock copolymer nanoparticles with distinct compositions and dimensions—resembling pseudo-proteins—undergo spontaneous self-sorting during occlusion within growing calcite crystals, yielding artificial biominerals in which two nanoparticle populations are selectively localized in distinct crystalline domains. Using in situ monitoring techniques and atomic force microscopy, we demonstrate that this self-sorting process arises from nanoparticle surface chemistry, which leads to differing polymer–mineral interfacial interactions. Moreover, the resulting composite crystals exhibit spatiotemporal release of the occluded species, highlighting the potential for advanced delivery systems. More broadly, self-sorting occlusion establishes a conceptual framework for understanding the spatial organization of organic components in biominerals and provides a versatile strategy for the rational design of next-generation biomimetic materials.

Adaptive molecular convergence is pervasive across deep time and largely decoupled from phenotypic convergence

Reuse of homologous genes during the evolution of similar traits or ecological transitions is often taken as evidence that evolution is repeatable at the molecular level. To study gene reuse, biologists frequently select specific convergent phenotypes and search for signatures of natural selection in genomes associated with those phenotypes. However, the causes and frequency of genome-scale molecular convergence remain unresolved, especially over deep timescales. We use phylotranscriptomics and analyses of sequence evolution to show that adaptive molecular convergence—defined as excess convergence of nonsynonymous substitutions between homologs, consistent with positive selection—is widespread across Medusozoa. Molecular convergence declines slightly over time but persists among lineages separated by over 600 My, consistently exceeding null expectations based on random overlap. Moreover, lineages sharing repeatedly evolved phenotypes (eyes, medusa loss, and upright colonies) do not exhibit elevated molecular convergence relative to other comparisons. Instead, convergence occurs idiosyncratically among species pairs and is broadly concentrated in genes associated with environment-facing functions, including metabolism, immunity, and xenobiotic processing. Our results suggest that selection often drives similar protein substitutions in disparate lineages, but that the selective causes of molecular convergence reflect multifaceted, lineage-specific interactions between organisms and their environments.