Science Advances

Nitazenes are driving a wave of overdose deaths in the United States and Europe and often require additional doses of naloxone to reverse. To understand the molecular basis, we conducted a joint experimental and simulation study of three common nitazenes, eto-, etodes-, and protonitazene. Radioligand experiments demonstrated that all three nitazenes display higher receptor affinity and longer dissociation half-lives than fentanyl. Notably, protonitazene dissociates slower than carfentanil and its displacement requires fourfold higher antagonist concentrations. The observed trend in nitazene half-lives is recapitulated by molecular dynamics simulations, which suggest that kinetics is controlled by specific interactions with two receptor subpockets. A newly published cryo-EM structure of fluetonitazene-OR complex confirms the predicted interactions, including a{pi} -hole bond between the nitro group and Tyr1.39, a residue recently shown to modulate OR signaling bias. Our findings suggest slow receptor dissociation as a key factor challenging overdose reversal. The mechanistic insights have implications for understanding opioid toxicity and designing more effective countermeasures.

Dietary patterns worldwide have shifted toward increased consumption of ultraprocessed foods (UPFs), which has been linked to higher disease burden. One mechanism proposed to impact both their consumption and contribution to metabolic disease is altered post-ingestive metabolic response in comparison to nutritionally similar foods. Here, we recruited 57 healthy-weight 18-45-year-old adults to examine the effects of food processing on postprandial metabolism and brain response. Despite nutritional matching, UPF meals evoked a greater insulinemic and energetic response with attenuated carbohydrate oxidation relative to non-UPF meals. Next, between-condition differences in peak carbohydrate oxidation were associated with mesolimbic and superior temporal gyrus activation in response to food cues. Finally, although food value did not differ between conditions, brain responses correlated with food valuation were positive for non-UPF but negative for UPF in visual cortex and striatum. These findings demonstrate that food processing influences post-ingestive metabolism in a way that could help explain long term health effects and differences in food reward through mechanisms beyond calories and macronutrient composition alone.

The adolescent brain is attuned to social and environmental exploration, allowing behavioral adaptation as experiences shape lasting patterns of morphological organization. Using a convolutional neural network on longitudinal structural MRI data, we assess the early part of this developmental window and derive latent brain representations reflecting patterns of structural variability linked to personal, social, and neighborhood conditions in adolescence. These representations offer a flexible framework for mapping brain-trait associations in adolescence and beyond.

Animals rely on olfaction to locate food, mates, and suitable habitats, yet natural odour environments contain thousands of volatile molecules, creating a high-dimensional sensory problem for both nervous systems and the researchers who study them 1-5. For example, a banana emits around 100 individual volatiles4,6. It remains unclear which components of complex odour blends animals have evolved to use as behavioural cues. Here, combining fieldwork, chemical and behavioural analyses, we show across multiple Drosophila species that behaviourally relevant cues can be predicted directly from the statistical structure of natural odour environments. Animals preferentially respond to components that are most distinctive within their natural host odour blends, and therefore most ecologically informative. These cues can be either major or minor blend components. Our results indicate that host-guided olfactory behaviours have evolved to exploit the statistical structure of natural odour environments by selectively targeting the most informative features of odour blends.

In their recent study entitled "Ancient DNA reveals the co-existence of domestic horses, donkeys and their hybrids in the prehistorical northwestern China", Li and colleagues (2026) report the genetic identification of three horses, three donkeys and four first-generation hinny hybrids dating to 400-160 BCE from the Mazongshan jade mining site in northwestern China. While a re-analysis of their ancient DNA sequence data confirms the horse and donkey identifications, it indicates that the four putative hinny specimens were, in fact, donkeys. This revision removes the primary evidence originally shown for the presence of hinnies at this site. Therefore, new data from the Mazongshan bone assemblage are required to support the proposed role of hinny hybrids as integral components of trans-regional trade networks during the Late Warring States and Early Han periods.

Animal venoms represent a major source of chemical novelty, yet how venom compounds originate, diversify, and are maintained across deep evolutionary timescales remains poorly understood. This gap is especially pronounced in cephalopods, which evolved venom systems used in predation, defense, and sexual competition, but whose venom genetic architectures, secretory cell types, and venom-producing glands remain largely unexplored. To date, only a single cephalopod venom compound with confirmed paralytic activity and a known primary sequence, SE-CTX from the golden cuttlefish Acanthosepion esculentum, has been described. Here, we reconstruct the evolutionary history, molecular diversity, and glandular localization of SE-CTX-like proteins using a multimodal approach. We identify 29 homologs across 20 squid and cuttlefish species and define a previously unrecognized venom gene family, which we name deca-ctx, specific to decapodiform cephalopods (squids and cuttlefish). Phylogenetic analyses reveal a single origin of deca-ctx followed by gene duplication and lineage-specific diversification, indicating long-term retention of this venom gene. Predicted DECA-CTX protein structures were separated into two clusters and 20 singletons highlighting potentially extensive structural diversity within a single cephalopod venom gene family. Proteomic analysis confirms expression of five DECA-CTX proteins across three species. Our imaging and histological analyses localize deca-ctx expression to specialized secretory cells within squid and cuttlefish venom glands. Together, these findings reposition SE-CTX as part of an evolutionarily and chemically diverse venom system, rather than an isolated venom protein, and establish cephalopods as a key lineage for investigating how new venom genes arise, diversify, and are integrated into functional venom arsenals.

Reactive oxygen species (ROS) regulate plant development and immunity, but how extracellular ROS signals are decoded and whether the Cysteine-rich Receptor-like Kinases (CRKs) truly serve as the long-suspected ROS sensors remains uncertain. Here, we combine high-throughput interactomics, redox proteomics, structural modelling, and genetics to map a ROS-dependent CRK interaction landscape in Arabidopsis thaliana. Using a redox-dependent interactome assay (RIACRK) on 40 CRK extracellular domains (ECDs), we identified ROS-modulated dimerisation networks with enhanced inter-community connectivity and hub redistribution in the presence of ROS. Integrating this with developmental and flg22-induced expression profiles reveals spatiotemporally limited subnetworks that likely function during activated immunity and leaf senescence, both of which are associated with extensive ROS production. Differential cysteine alkylation coupled with mass spectrometry shows that cysteines in a subset of CRK ectodomains undergo ROS-dependent oxidation. Notably, solvent-exposed, vicinal cysteines C228/C229 in CRK28 emerge as prime redox-sensitive candidates. CRK28 homodimerises and heterodimerises with CRK17 in vivo, and mutation of C228/C229 retains plasma membrane localisation but abolishes CRK28 homodimerisation, indicating a redox-controlled dimerisation switch. Loss of CRK28 delays senescence, while CRK28 overaccumulation from its native promoter causes dwarfism, premature senescence, autoimmune-like phenotypes, extensive phosphoproteome rewiring, and associations with Pathogenesis Related (PR) proteins, ROS-detoxifying enzymes, receptor(-like) kinases, and vesicle trafficking components. These results indicate that CRK28 is a potential ROS-regulated hub connecting extracellular redox signals to CRK network organisation, immune response, and age-related senescence.

Vaccination programs worldwide have effectively reduced the burden of childhood diseases, yet immune responses remain highly heterogeneous among individuals. While host characteristics such as age and sex are established determinants of vaccine immunogenicity, the timing of vaccination, specifically the calendar season of vaccination, remains largely underexplored. Although circadian rhythms are known to regulate daily immune function, evidence for long-term circannual patterns has been limited by the difficulty of collecting year-round vaccination data across diverse populations. Here, we show that the season of vaccination systematically shapes the immune response across a broad range of pediatric vaccines. By leveraging data from 96 randomized control trials worldwide, including over 48,000 children vaccinated against 14 pathogens, we demonstrate that immunogenicity after vaccination follows a pronounced latitudinal gradient, typically peaking during colder months in temperate regions and exhibiting distinct variability in the tropics. These findings suggest that the circadian human immune response might extend to a circannual scale, potentially synchronized by environmental cues. Incorporating the season of vaccination into the design of clinical trials and public health campaigns may optimize vaccine performance and enhance seroprotection.

The effect of climate change on the nutritional quality of plants is poorly understood even though it may have major implications for the food chain and ecosystems. Here we use a dataset covering > 1450 plant species to identify the factors driving plants nutritional properties and develop global projections. We reveal that plant type, CO2, and solar radiation are major drivers controlling nutritional properties. Projections for 2050 show a decline in nutritional quality (-8%, on average at the global scale), measured as the protein to fiber ratio, a strong decrease in minerals (-18%), and a small decrease in digestibility (-3%). Plants in arid and tropical areas will experience the largest decline in quality, which will decline minimally in temperate areas and improve in cold, and polar regions. Quality trends will be opposite in grasses. These results have important implications for livestock management and wildlife conservation.

The mammalian kidney relies on a branched network of collecting ducts for fluid transport and homeostasis. Replicating this network in vitro would parallelize function in synthetic replacement kidneys, yet current organoids have limited branching capacity. Here, we establish a developmentally-informed strategy to control organoid budding through optogenetic control of a receptor tyrosine kinase, RET. We first show pharmacological manipulation of RET signaling controls the extent of branching in mouse embryonic kidneys and human stem cell-derived kidney organoids. Next, we develop an optogenetic RET receptor (optoRET) that signals in a ligand-independent manner via blue light-mediated clustering. Epithelial cells expressing optoRET reproduce stereotyped RET signaling, scattering, and symmetry breaking in response to blue light. Human kidney organoids undergo budding with controllable orientation in response to spatially patterned optoRET stimulation. Our results establish ligand-free optogenetic control of branching and inspire new synthetic biology strategies for epithelial organoid design. HighlightsGDNF-RET controls branching and tip cell state in mouse and human kidney tissues. OptoRET reproduces endogenous RET signaling and morphogenesis in cell lines. OptoRET enables ligand-free budding in human renal epithelial organoids. Spatially patterned optoRET stimulation controls budding orientation.

Auxin, a central hormone coordinating plant growth, integrates both environmental and developmental signals to regulate cell expansion, division, and organ patterning. Among these environmental cues, elevated ambient temperatures trigger a suite of developmental adaptations collectively known as thermomorphogenesis. In this study, we identify nitric oxide (NO) as a key mediator in the temperature-dependent regulation of auxin signaling. Our results show that warm temperatures (28-29 {degrees}C) enhance auxin-induced NO accumulation in Arabidopsis thaliana seedlings. Using pharmacological and genetic approaches, we demonstrate that NO is required for proper thermomorphogenic responses in aerial tissues. This redox signal promotes the stabilization and nuclear localization of the F-box auxin receptor TIR1, a crucial step for the activation of downstream auxin responses. Specifically, tir1-1 seedlings expressing a non-nitrosylatable TIR1 variant mutated at the Cys140 residue exhibit impaired hypocotyl elongation and hyponasty under warm conditions compared to seedlings complemented with wild-type TIR1. These results highlight the functional relevance of the TIR1 Cys140 residue, a known target for S-nitrosylation, in coordinating thermomorphogenic responses. In contrast, the absence of TIR1 S-nitrosylation restricts primary root elongation at 22 {degrees}C but does not affect the growth-promoting effects of warm temperatures. Our findings uncover a novel redox-dependent regulatory layer in auxin signaling, where S-nitrosylation of TIR1 may modulate its stability and subcellular localization in a temperature- and organ-specific manner. This mechanism allows differential growth responses between shoot and root organs and highlights the complexity of hormonal and redox interplay during plant adaptation to elevated temperatures.

Recent studies pioneered the use of classic hallucinogens as rapid-acting antidepressants (RAAD). To further understand the link between their neuromodulatory and antidepressant effects, we combine pharmacodynamic profiles of four classic hallucinogens and the anaesthetic Ketamine with receptor density distributions from both Positron Emission Tomography (PET) and layer-resoluted autoradiography studies to develop anatomical distribution profiles of drug action strengths giving a comparative measure how strong a drug would act in a region of interest. PET-based, we find high action strengths in association cortices for classic hallucinogens, which we contextualise anatomically using functional and cytoarchitectural measures. Autoradiography-based, we observe high action strengths in the supragranular layer and multimodal temporal areas. Finally, we show how Ketamines affinity to high-affinity subtypes of 5-HT2a and D2 receptors produce classic hallucinogen-like neuroanatomical trends. Through highlighting high RAAD action strengths in regions with emotion processing functionality, our results contribute to a mechanistic understanding of rapid antidepressant action.

To elucidate the contribution of chromatin modifications in plant cold response, we performed ChIP-seq for H3K27me3 and H2A.Z in Arabidopsis exposed to short-term cold. We combined our epigenetic data with NET-seq to investigate the direct transcriptional effects of histone marks. Prior to any stress cue, cold regulated genes share a similar chromatin environment with high H2A.Z and H3K27me3. H3K27me3 levels do not correlate with transcriptional activity or elongation speed. However, REF6-mediated reduction of H3K27me3 is essential for regulation of cold controlled genes. H2A.Z occupancy changes revealed a negative correlation between cold-induced changes to H2A.Z and RNAPII activity at differentially expressed genes. Importantly, changing H2A.Z levels preceded transcriptional changes, indicating that the variant functions as a critical cold-induced switch. Further, our data suggests that high H2A.Z levels slow down RNAPII. Thus, H2A.Z is essential for the transcriptional response and a decreased H3K27me3 level is important for the genomic adaptation to cold.

Bone formation during embryonic development requires the rapid and sustained delivery of large amounts of calcium to mineralizing tissue. In avian embryos, this process coincides with a unique physiological transition in calcium supply, shifting from limited yolk reserves to massive mobilization from the eggshell. To address the question of how calcium transport responds to the increasing mineral demand during this transition, we combine micro computed tomography with three-dimensional cryogenic FIB-SEM imaging at different embryonic stages in the developing quail femur. Over this developmental period, bone mineralized volume increases rapidly through periosteal expansion. We observe that bone forming cells consistently contain numerous membrane-bound carriers loaded with mineral precursors throughout all growth stages. By integrating measurements across length scales, we calculate the intracellular velocities required to sustain the observed mineral deposition in the successive developmental stages. Surprisingly, these velocities remain within a similar range across development, despite the significant difference of bone formation rates, and are consistent with active transport by molecular motors. The increasing mineral demand corresponds to the expansion of mineralizing surfaces, which leads to an increasing number of cells, while the transport capacity of individual cells remains similar. Our work reveals a perfect tuning between the calcium transport capacity and bone growth, even in a situation where the skeletal growth is accelerating in the quail embryo. Significance statementDespite the importance of bone mineralization for the integrity of the skeleton, surprisingly little is known about how calcium is transported across the organic matrix to the mineralization sites during embryonal development. Using an avian model, where the main source of calcium shifts from a limited contribution from the yolk to the massive reservoir in the eggshell, we quantify bone mineral deposition using tissue level characterization together with three-dimensional cryogenic nanoscale imaging. We discover that intracellular vesicles containing mineral precursors are transported at similar speed, although the overall mineral deposition rate is increasing six-fold from embryonal day 10 to 14. This shows that the acceleration in mineralization activity is due to an increased number of bone cells rather than to a larger workload for individual cells. These findings demonstrate that rapid bone development is regulated to synchronize growth rates and mineral transport.

The metabolic processes sustaining coral reefs, from carbonate and primary production to secondary production, remain poorly integrated and rarely quantified simultaneously at global scales. This hampers our ability to predict global responses to accelerating human pressures and manage coral reef functioning. Using metabolic scaling and bioenergetic models applied to surveys from 1,100 reefs worldwide, we provide a global, standardized quantification of 14 ecosystem functions spanning benthic (corals and algae) and fish communities. Our analysis reveals a continuous functional spectrum of global coral reefs organized along four dominant axes: 1) primary production, 2) calcification and habitat structure, 3) secondary biomass production and consumption, and 4) biomass turnover. Functions mediated by fish and benthic communities show weak associations at the global scale rather than tight coupling. Climate stressors reduced calcification and local human impacts lowered secondary production. Yet these directional effects unfolded against a backdrop of substantial natural variability in reef functional configurations, such that heavily and minimally impacted reefs overlap substantially in the global functional space. Temporal analyses across three representative reef systems further revealed that functional trajectories following disturbance are context-dependent, with no universal pattern of recovery across locations. This continuous and context-dependent functional spectrum challenges the notion of universal functional benchmarks and supports locally tailored conservation strategies.

Microplastics (MPs) are pervasive environmental contaminants and an emerging component of the human diet1, 2, yet their physiological effects remain poorly defined. Here we show that MPs are detectable in mineralized human bone under non-iatrogenic conditions and impair osteoblast mineralization in a donor-dependent manner. Using a physiologically relevant dietary exposure model, we demonstrate that chronic MP ingestion induces sex- and diet-dependent bone loss in mice, predominantly affecting trabecular architecture, in the absence of intestinal pathology or systemic inflammatory cytokine elevation. Instead, MP exposure selectively enhances gut-derived serotonergic signaling, with increased abundance and activity of enteroendocrine cells without evidence of lineage reprogramming. Single-nuclei transcriptomic profiling of the colon resolves enterochromaffin cells and serotonergic target expression across epithelial and enteric neuronal compartments, revealing discrete mechanosensory adaptations without inflammatory activation. Together, these findings implicate ingestion of MPs as bioactive dietary contaminant that disrupt gut-endocrine communication and compromise skeletal homeostasis, uncovering a previously unrecognized pathway linking environmental plastic exposure to bone health.

Male rodent sexual behavior progresses from appetitive to consummatory mating, implying a sustained internal motivational state. Estrogen receptor 1 (Esr1)-expressing neurons in the medial preoptic area (MPOA) regulate discrete mating actions, but how motivational drive is sustained across mating remains unknown. Here, we identify an MPOA Esr1+ neuronal subtype marked by proenkephalin (Penk) that promotes the transition from mount to intromission. Male mice exhibited a bimodal progression to consummatory mating, and Penk-expressing neurons represented the predominant population recruited for consummatory behaviors. In sexually active males, Penk+ neurons exhibited sustained Ca{superscript 2} dynamics. Chemogenetic manipulation selectively enhanced female-directed consummatory behaviors without affecting intermale interactions. Optogenetic activation of Penk+ neurons or their terminals promoted consummatory behavior over a behaviorally relevant timescale. Thus, MPOA Penk+ neurons provide a circuit substrate for a sustained internal state that ensures successful mating progression.

Deep learning has transformed medical image and video analysis, but it usually requires large, well annotated datasets. In many clinical domains, especially when testing novel mechanistic hypotheses, such retrospective datasets are hard to obtain since acquiring adequate cohorts is time intensive, costly, and operationally difficult. This creates a critical translational gap: scientifically compelling early stage ideas may remain untested due to lack of sufficient sample size to support conventional deep learning pipelines. Developing data-efficient strategies for evaluating new hypotheses within small prospective cohorts is therefore essential to de-risk innovation before large-scale validation. Myofascial Pain Syndrome (MPS) exemplifies this challenge, as quantitative ultrasound imaging biomarkers for MPS remain underexplored. We investigated whether MPS in the upper trapezius can be detected from full B-mode ultrasound videos in a small prospective cohort (11 controls, 13 patients). Videos were automatically preprocessed and resampled using a sliding window strategy to expand training samples (404 clips). A self-supervised Video Diffusion Encoder (VDE) is developed to learn spatiotemporal representations without relying on extensive labeled data, and compared it with transfer-learning-based ResNet, VideoMAE, and SimCLR. Using subject-level stratified four-fold cross-validation, the VDE outperformed transfer learning baselines and achieved performance comparable to SimCLR, with subject-level AUC of 0.79 and accuracy of 0.86, and no significant differences between latent-only and combined trigger point analyses. These results demonstrate that self-supervised diffusion learning can support robust, data-efficient deep learning in small prospective studies, enabling early feasibility testing of innovative ultrasound biomarkers before large-scale clinical trials.

The association of ferredoxin-NADP+ reductase (FNR) with thylakoid membranes constitutes a central regulatory node in photosynthetic electron transport, governing NADPH production essential for carbon fixation. In cyanobacteria and higher plants, this interaction is mediated by an intrinsic FNR domain or specialized proteins, yet the mode of recruitment in green algae has remained enigmatic. Here, we show that in the green microalga Chlamydomonas reinhardtii, FNR is directly tethered to photosystem I-LHCI (PSI-LHCI) through a conserved N-terminal -helix of the antenna protein Lhca4. Cryogenic electron microscopy localizes FNR to the stromal side of PSI proximal to Lhca4, while AlphaFold modeling identifies a specific interaction interface, which we validate using isothermal titration calorimetry. Structural modeling further reveals that the spatial separation between PSI-bound FNR and ferredoxin (Fd) is incompatible with direct electron transfer, indicating that it occurs sequentially rather than through a stable PSI-Fd-FNR complex. Comparative analysis demonstrates that the FNR-binding N-terminal motif of Lhca proteins is conserved across diverse green microalgae, suggesting an evolutionarily conserved strategy for positioning FNR at PSI. Collectively, our results uncover a novel mechanism for FNR recruitment and establish a new principle by which photosynthetic electron partitioning is regulated through spatial organization of electron transfer components.

Neural activity emerges from interactions between local cellular architecture, neuromodulatory systems, and large-scale cortical networks. Yet it remains unclear how this multiscale biological context constrains electrophysiological dynamics in humans and how this changes across the lifespan. We combined resting-state magnetoencephalography (MEG) from 350 adults (18-88 years) with cortical maps reflecting cytoarchitecture, myelination, metabolism, gene expression, and neurotransmitter receptors in a multivariate prediction framework. Specific markers explained most regional variance in MEG power spectra and temporal autocorrelation, similarly for both measures, revealing frequency- and timescale-specific signatures that followed canonical spectral boundaries. Age-related MEG patterns spatially aligned with markers of neuroinflammation, monoaminergic-cholinergic signaling, cortical development and myelination, and cerebrovascular organization. This work identifies key components of an anatomical and molecular scaffold and their relative importance for neural activity across the lifespan, informing future experimental perturbations and generative models.