Biology subjects

Yang, Y.

Publications and source records attributed to Yang, Y..

At least 73 records · Page 4Linked to original sources

bioRxiv2026

Targeting the Oxysterol Receptor GPR183 to Mitigate Fibrogenesis in Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a progressive and ultimately fatal lung disease with a median survival of 3-5 years after diagnosis. Current antifibrotic therapies slow disease progression, but do not halt or reverse fibrosis, underscoring the need for new therapies. We identified a dysregulated oxysterol-GPR183 axis as a driver of IPF. Oxidized cholesterols were elevated in lungs from IPF patients, with myofibroblasts representing the dominant source of 7,25-hydroxycholesterol (7,25-OHC), the endogenous high affinity ligand for the oxysterol-sensing receptor GPR183. IPF patients had increased GPR183 expression in interstitial and monocyte-like macrophages compared to controls. In a bleomycin-induced model of pulmonary fibrosis genetic deletion of GPR183 reduced disease severity characterized by reduced fibrosis, inflammation, and accumulation of macrophages and myofibroblasts. Pharmacological inhibition of GPR183 with the antagonist NIBR189 attenuated fibrosis when administered preventatively from day 1-7 after bleomycin exposure. Notably, therapeutic treatment with the GPR183 antagonist after commencement of fibrosis development at day 10 post-bleomycin also significantly reduced fibrotic pathology, achieving efficacy comparable to the approved antifibrotic nintedanib. However, the GPR183 antagonist was more potent in reducing inflammation and myofibroblast activation compared to nintedanib. Together, these findings identify an oxysterol-GPR183 signaling axis that contributes to pulmonary fibrogenesis and provide a strong preclinical rationale for targeting GPR183 as a novel therapeutic strategy for IPF. One Sentence SummaryTargeting GPR183 reduced lung fibrosis and inflammation in a preclinical model, supporting GPR183 as a promising new therapy.

immunology↗

bioRxiv2026

Postmitotic Regulation of Neuronal Subpopulations in the Cerebellum

Hundreds of neuronal cell types and subtypes have been identified through transcriptome profiling of the mammalian brain and are thought to arise from lineage-restricted neural progenitors during early development. However, how neurons might further diversify their transcriptional identities during postmitotic development and through adulthood remains poorly understood. Here, we combine genetic and biochemical approaches to uncover granule neuron subpopulations in the anterior cerebellum, which we term C1 and C2. We find that a large proportion of granule neurons predominantly express the C2 gene program during early postmitotic differentiation, but that C2 genes are downregulated in a subset of neurons during late postnatal development, leading to comparable proportions of C1 and C2 neurons in adulthood. Using an in vivo genetic mini-screen, we identify calcium signaling pathways, together with the transcription factor ETV1, that establish the transcriptional program of C2 neurons. Finally, C1 and C2 granule neurons are differentially engaged during behavior and this reflects their roles in cerebellar-dependent associative learning. Together, these findings reveal postmitotic mechanisms that continue to shape neuronal identity in the brain.

neuroscience↗

bioRxiv2026

Plasma membrane PI4P recruits SNAP47 to mediate SNARE-dependent AMPAR exocytosis during synaptic potentiation

The synaptic delivery of the AMPA-type glutamate receptors (AMPARs) is crucial for longterm potentiation (LTP) of excitatory synapses, yet the mechanisms underlying neuronal activity-dependent AMPAR exocytosis at the plasma membrane (PM) remain unclear. We previously demonstrated that the PM synthesis of the phosphoinositide PI4P is enhanced upon LTP induction and that PM PI4P, not PI(4,5)P2, is required for activity-induced AMPAR exocytic trafficking. Here, we show that AMPARs are exocytosed at PI4P-enriched dendritic PM microdomains in potentiated hippocampal neurons. The Q-SNARE SNAP47 binds PI4P via its pleckstrin homology (PH)-like domain. This interaction recruits SNAP47 to the PM, promoting the exocytic fusion of AMPAR vesicles through the SNAP47-Syntaxin-3-VAMP2 SNARE complex. In the hippocampus, the SNAP47-PI4P interaction is necessary for both LTP and long-term memory. Our findings reveal a mechanistic role for PI4P in mediating activity-dependent, SNARE-driven fusion of AMPAR exocytic vesicles with the PM.

neuroscience↗

bioRxiv2026

Selective GRAB sensors reveal distinct endocannabinoid dynamics in vivo

The endocannabinoid system modulates diverse physiological processes via two endogenous lipid ligands, 2-arachidonoylglycerol (2-AG) and anandamide (AEA); however, their specific spatiotemporal dynamics remain poorly understood owing to the lack of selective probes. Here, we developed GRAB2-AG2.0 and GRABAEA2.0, two genetically encoded fluorescent sensors that selectively detect 2-AG and AEA, respectively. Both sensors exhibited high apparent affinity and molecular specificity for their respective ligands, enabling the real-time detection of 2-AG and AEA release evoked by electrical stimulation in cultured neurons and acute brain slices. In freely behaving mice, these sensors revealed ligand- and context-specific eCB dynamics: aversive stimulation preferentially evoked 2-AG, whereas psychoactive drugs produced distinct 2-AG and AEA responses. Notably, {Delta}9-THC elicited a sustained 2-AG signal in the nucleus accumbens shell, and local deletion of Dagla markedly attenuated both this signal and {Delta}9-THC-induced hypolocomotion. These sensors therefore enable detecting 2-AG and AEA signaling seperately and reveal an endogenous 2-AG component of the behavioral response to {Delta}9-THC.

neuroscience↗

bioRxiv2026

RNA-seq meta-analysis and machine learning identify stress-responsive genes and improve genomic prediction in common bean (Phaseolus vulgaris L.) with cross-species application in cowpea (Vigna unguiculata L.)

Common bean (Phaseolus vulgaris L.) is exposed to a broad spectrum of abiotic and biotic stresses that impose severe constraints on productivity, yet the molecular basis of stress tolerance remains poorly resolved, with independent studies yielding inconsistent and incomplete conclusions. To establish a comprehensive picture of the common bean stress transcriptome, we conducted a systematic meta-analysis of publicly available RNA-sequencing datasets spanning abiotic and biotic stress conditions across leaf and root tissues. Integrating statistical meta-analysis with machine-learning approaches, we identified stress-responsive gene sets whose robustness was verified through rigorous statistical approaches including independent dataset validation. Beyond confirming established stress-responsive genes, the machine-learning framework uncovered candidates overlooked by standard significance thresholds in individual studies yet carrying consistent transcriptional signals across studies. Co-expression and protein-protein network analyses further resolved these candidates into functionally coherent modules linked to specific stress-response programs. Notably, ethylene-responsive transcription factors were identified as hub genes in three of four stress-tissue groups, with NAC domain transcription factors emerging as additional hub genes in biotic stress contexts. Importantly, the biological significance of the identified gene sets was validated genomically: marker panels targeting consensus meta-analysis-derived and machine-learning-discovered gene regions improved genomic prediction accuracy for disease resistance traits in common bean and abiotic stress tolerance traits in cowpea relative to a baseline model with equivalent-sized random marker sets. Overall, these findings revealed conserved stress transcriptome signatures in common bean and provided a cross-species, evidence-based framework for prioritizing candidate genes and constructing biologically informed genomic selection tools to advance stress-resilient legume breeding.

genetics↗

bioRxiv2026

Photometallobiocatalytic Asymmetric Radical-Mediated Cross-Coupling of Organotrifluoroborate Salts and Pyridotriazoles

The cooperative integration of photoredox catalysis and metalloenzyme catalysis has emerged as a powerful strategy for enabling stereoselective radical transformations beyond the capabilities of either catalytic mode alone. Herein, we report a photometallobiocatalytic enantioselective intermolecular C-C cross-coupling of pyridotriazoles and secondary alkyltrifluoroborate salts through cooperative catalysis between an organic photosensitizer and an engineered protoglobin. By combining visible-light-mediated radical generation with enzymatic activation of pyridotriazoles to form reactive Fe carbenoid intermediates, this transformation enabled highly enantioselective radical C-C bond formation through a proposed outer-sphere coupling mechanism. Through biocatalyst mining and directed evolution, engineered Aeropyrum pernix protoglobin catalysts were developed that catalyzed this radical C-C coupling with excellent efficiency and stereocontrol. The photobiocatalytic platform exhibited a broad substrate scope with respect to both secondary alkyltrifluoroborate salts and pyridotriazoles, affording a range of valuable N-heterocyclic products in excellent yields and enantioselectivities. Mechanistic studies supported the involvement of radical intermediates and revealed spontaneous binding between the photocatalyst eosin B and the engineered metalloenzyme. By leveraging cooperative photometallobiocatalysis, this work established an underexplored strategy for asymmetric intermolecular radical cross-coupling via an outer-sphere mechanism, further expanding the catalytic repertoire of transition-metal carbenoid chemistry. Entry for the Table of Contents O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=83 SRC="FIGDIR/small/744224v1_ufig1.gif" ALT="Figure 1"> View larger version (12K): org.highwire.dtl.DTLVardef@39f55borg.highwire.dtl.DTLVardef@11b3dfeorg.highwire.dtl.DTLVardef@1832ac2org.highwire.dtl.DTLVardef@6c4f56_HPS_FORMAT_FIGEXP M_FIG An enantioselective photometallobiocatalytic cross-coupling of pyridotriazoles and secondary alkyltrifluoroborate salts is developed. Cooperative catalysis using eosin B and an engineered protoglobin combines visible-light-mediated radical generation with enzymatic metal carbenoid activation, affording valuable N-heterocyclic products in excellent yield and enantioselectivity through an outer-sphere radical coupling pathway. C_FIG

biochemistry↗

bioRxiv2026

CD59 organizes the plasma membrane to sustain oncogenic Ras-MAPK signaling and is a targetable vulnerability in acute myeloid leukemia

Acute myeloid leukemia (AML) is a clinically heterogeneous disease. Although the genetic abnormalities associated with poor prognosis are well defined, how they drive unfavorable outcomes remains unclear. Using published gene-expression and dependency datasets, we searched for cell-surface protein-coding genes associated with poor survival and required for AML growth, prioritizing this class of proteins for its accessibility to biologics. This search identified CD59, a GPI-anchored protein with a canonical role in complement regulation, whose high mRNA expression correlates with adverse-risk genetics and stemness signatures. CD59 silencing impaired proliferation across genetically diverse AML cell lines, reduced leukemic burden, and extended survival in cell xenograft models. Moreover, CD59 expression was enriched on leukemic stem cells (LSCs), and its depletion impaired LSC self-renewal and primary AML engraftment in vivo while sparing normal hematopoiesis. Mechanistically, these effects reflected a non-canonical role for CD59 in sustaining Ras-MAPK signaling, whereby its loss depleted inner-leaflet phosphatidylserine and impaired Ras and c-Raf membrane recruitment and activation. rILYd4, a recombinant fragment of the bacterial toxin intermedilysin that binds and degrades CD59, recapitulated these effects and sensitized cells to venetoclax in vivo. These findings reveal CD59 as a critical regulator of Ras-MAPK signaling required for AML growth and nominate its rILYd4-mediated degradation as a therapeutic strategy.

cancer biology↗

bioRxiv2026

Neural mechanisms of impaired self-compassion in depressed adolescents during social exclusion

Background: Self-compassion has shown to be an effective emotion regulation strategy, but its neural mechanisms remain understudied in adolescents with depression who suffer from social exclusion. This study employed event-related potentials to investigate the psychophysiological mechanisms underlying impaired self-compassion in adolescents with depression during social exclusion. Methods: Thirty-seven adolescents with major depressive disorder (age = 16.46 +/- 2.02) and thirty-two demographically matched healthy controls (age = 16.54 +/- 2.29) completed a social exclusion scenario imagination task. This task presented participants with social exclusion scenarios, asking them to imagine themselves as the excluded individual and subsequently rate their negative emotions. The regulation session required participants to use self-compassionate statements to regulate their emotional responses while imagining and rate how much self-compassion they have engaged in; the non-regulation required them not to use those statements and rate their negative emotions immediately following imagination. EEG signals were recorded during the task, and the late positive potential (LPP) was analyzed to examine the neural responses associated with self-compassion regulation following social exclusion. Results: Compared with the non-regulation condition, both groups showed less negative emotion during the self-compassion regulation condition. Adolescents with depression exhibited significantly lower self-compassion ratings than healthy controls, and showed a significantly smaller decrease in negative emotions. Higher self-compassion ratings were correlated with greater emotion regulation effect, particularly in adolescents with depression. Furthermore, LPP amplitudes were significantly higher in adolescents with depression than in healthy controls during both regulation and non-regulation conditions. Conclusions: Adolescents with depression were characterized by impairment in using self-compassion to downregulate negative emotions when confronted with social exclusion. LPP amplitudes were consistently elevated in adolescents with depression, underscoring their potential as a critical focus for psychophysiologically-informed therapies.

neuroscience↗

bioRxiv2026

Gaussian Accelerated Molecular Dynamics in GROMACS

Gaussian accelerated molecular dynamics (GaMD) enhances conformational sampling by adding a smooth boost potential without requiring predefined collective variables, but an engine-integrated implementation has not been available in GROMACS. Here, we implement total-, dihedral-, and dual-boost GaMD in GROMACS 2025.4, including staged energy-statistics collection, GPU-based bias evaluation and force scaling, restart support, and outputs required for cumulant-based free-energy reweighting. The implementation was evaluated using four benchmark systems spanning conformational free energies, protein folding, and ligand recognition. For alanine dipeptide, a reweighted 100 ns GaMD trajectory recovered the major free-energy basins and rotational barriers in overall agreement with a 1000 ns conventional MD simulation. For chignolin and TC5b, all three independent trajectories for each system sampled native-like folded states from extended conformations within 300 ns and 1 s, respectively; the best TC5b structure had a minimum backbone RMSD of 0.03 nm from the experimental structure. In the benzene-T4 lysozyme system, two of five independent 500 ns trajectories captured both ligand binding and dissociation, yielding a bound pose with a minimum ligand RMSD of 0.06 nm from the crystal structure. Across all four systems, the boost-potential distributions were approximately Gaussian, and second-order cumulant reweighting resolved the expected conformational and binding free-energy basins. These results demonstrate that GROMACS-GaMD provides a practical, GPU-enabled, collective-variable-free enhanced-sampling framework for biomolecular free-energy calculations, protein folding, and ligand-binding studies.

biochemistry↗

bioRxiv2026

High-Specificity Detection of Chromosomal Mosaicism Reveals Cell-Type-Specific Genomic Alteration Patterns in Aging Tissues

Mosaic chromosomal alterations (mCAs) increase with age and are associated with multiple diseases, yet the cell types and states that harbor these alterations remain largely unknown. Because mCAs arise in individual cells prior to clonal expansion, they are typically rare and obscured in bulk data. We develop CHASM, a method for detecting chromosomal copy number alterations (CNA) from single-cell chromatin accessibility (scATAC-seq) data, a scalable modality that captures both cell state and chromosomal alterations. CHASM estimates a CNA-null background for each cell, providing an individualized expectation for chromosomal accessibility, which is critical in non-neoplastic tissues where alteration-carrying cells are not readily distinguishable from normal. By comparing each cell against its expected background, CHASM distinguishes chromosomal alterations from background variation and achieves more stringent control of false positives. We validate CHASM using in silico spike-in experiments, cross-modality comparisons with matched single-cell DNA and RNA data, and established genome-instability contrasts, including p53 deficiency and chromosome Y loss. Applied to multiple aging data sets, CHASM consistently recovers mCA burden in age-susceptible cell populations and reveals aging-associated signatures not detected by existing methods. In a cohort of 99 human kidney samples spanning age and disease conditions, CHASM identifies enrichment of mCAs in injury-associated cell states (VCAM1-high proximal tubule cells). Notably, CHASM detects the age-associated emergence of mCAs in cancer-relevant genomic regions, including chromosomes 3 gains and losses and chromosome 7 gain, in ostensibly normal cell populations. Cells harboring mCAs exhibit activation of injury-response regulatory programs and reduced epithelial identity programs, while elevated mCA burden in specific epithelial populations are associated with increased immune and stromal infiltration. Overall, we develop CHASM for high-specificity detection of CNA at single cell resolution. Applied across tissues, CHASM reveals aging-patterns of genome instability within cell types and implicates mCAs in early, pre-disease cellular states.

bioinformatics↗

bioRxiv2026

Bone Lymphatic Endothelial Cells Form a Distinct Skeletal Population and Drive Skeletal Repair

Bone regeneration relies on specialized vascular niches, yet the contribution of lymphatic vessels across distinct skeletal sites remains poorly understood. Here, we identify bone lymphatics as an essential component of the regenerative microenvironment in the mandible and long bones. We demonstrate that bone lymphatic endothelial cells (LECs) constitute a specialized endothelial population that is transcriptionally and spatially distinct from periosteal LECs. During skeletal repair, bone LECs reactivate a regenerative transcriptional programme, and promote mandibular and fracture healing. In osteonecrosis of the jaw and periodontitis, bone lymphatic-associated signalling is disrupted, identifying impaired lymphatic function as a shared feature of mandibular disease. Therapeutic activation of VEGFC-FLT4 signalling during injury or mandibular disease restores lymphangiogenesis, enhances osteogenesis, and markedly improves bone regeneration. Together, our findings advance the paradigm-shifting role of bone lymphatics positive regulators of bone regeneration and identify lymphatic activation as a promising therapeutic strategy to enhance bone regeneration in mandibular diseases.

cell biology↗

bioRxiv2026

Circadian Clock Gene Modulation and Selective Reprogramming in Response to Virus Infection

The circadian clock regulates fundamental cellular processes that include the host response to infection. However, the intersection of the circadian clock and the mechanisms that drive antiviral immunity remains poorly understood. Copy-back viral genomes (cbVGs) generated during virus replication strongly stimulate immunity during infection with negative-sense RNA viruses. Here, we demonstrate at the single cell level that A549 lung epithelial cells, commonly used to model lung infections, sustain circadian rhythms and upon infection with Sendai virus (SeV) progressively remodel the circadian clock through an innate immune response driven primarily by cbVGs. Furthermore, we show that cbVG-driven changes in circadian gene expression are mediated through two distinct innate immune sensing pathways: the RIG-I adaptor MAVS is required for preferential induction of the BMAL1 paralog ARNTL2, whereas the double-stranded RNA sensor PKR is required for the cbVG-specific induction of the negative-feedback regulators NR1D1, NR1D2, and PER1. A similar cbVG-specific signature was observed during respiratory syncytial virus infection, suggesting that cbVG-driven circadian gene regulation is not unique to SeV. In addition, we established through gain- and loss-of-function experiments that ARNTL2 is functionally required for amplifying the transcriptional response to infection, with selective effects on the expression of specific antiviral genes, including CCL5. Together, these findings establish innate immune signaling triggered by cbVGs as selective driver of circadian clock gene expression during viral infection through distinct sensing pathways and identify ARNTL2 as a previously unrecognized regulator of virus-induced host transcriptional responses.

microbiology↗

bioRxiv2026

Structure of a key adhesin-exopolysaccharide interaction provides insights into matrix assembly in Vibrio cholerae biofilms

Biofilms serve as a protective mechanism for bacteria, including many pathogens. To form such communities, bacteria secrete macromolecules that form an extracellular matrix serving as a barrier against environmental threats, such as predation, antibiotics, and the host immune system. To be effective, a biofilm must anchor to foreign surfaces and retain sufficient stiffness, in the environment or in a host. However, how this matrix self-organizes to support biofilm formation remains a mystery at the molecular level. The human pathogen Vibrio cholerae produces biofilms primarily composed of an exopolysaccharide called VPS (Vibrio polysaccharide), consisting of an unusually-modified repeating tetrasaccharide core unit. VPS engages with two secreted adhesion proteins, Bap1 and RbmC, which adhere the biofilm to abiotic and biotic surfaces, and serve to strengthen the biofilm by interacting with VPS using a conserved {beta}-propeller. To pinpoint the interaction between the adhesins and purified segments of VPS, we determined the [~]1.6 [A] X-ray crystal structure of Bap1 bound to fragmented VPS and used the structure to carry out molecular dynamics simulations. The structure revealed a single binding site consisting of one tetrasaccharide unit involving an induced magnesium binding site. Unexpectedly, the tetrasaccharide adopted a bent state caused by a rotation of the glycosidic bond between the central two monosaccharide units. Using a combination of mutagenesis, light scattering, and in situ fluorescent microscopy, we demonstrate that Bap1 not only facilitates biofilm adhesion, but is also required for proper VPS organization, through the identified binding pocket. Our structure reveals for the first time the interaction between a biofilm exopolysaccharide and matrix protein, as well as insights into conformational changes of exopolysaccharide induced by this binding. Our findings provide a generalizable approach for studying the biophysical and biochemical properties of carbohydrate-dependent biofilm assembly, which may lead to new ways to treat disease caused by biofilm-forming bacterial pathogens by disrupting the exopolysaccharide-protein interactions.

microbiology↗

bioRxiv2026

Brassinosteroid-auxin crosstalk shapes rice flag leaf angle to boost dense planting yield

Flag leaf angle (FLA) critically determines rice yield potential under dense planting conditions. As two pivotal phytohormones determine rice FLA, the antagonistic interaction between brassinosteroid (BR) and auxin remains largely uncharacterized. We here demonstrate that BR signaling reduces auxin biosynthesis to control FLA via regulating the biosynthesis of secondary cell wall (SCW). Genetic evidence demonstrates OsYUC8 mutants disrupt SCW formation, leading to increased FLA. At the molecular level, the BR-related transcription factor OsBZR1 directly binds to and represses OsYUC8 promoter activity, thereby fine-tuning auxin-mediated SCW biosynthesis. Field evaluations reveal that osbzr1 mutants display optimized flag leaf architecture and improved yield performance under high-density cultivation. Our study not only delineates the antagonistic BR-auxin interaction governing FLA but also establishes a genetic strategy for manipulating crop architecture to maximize yield in dense planting conditions. One-sentence summaryOsBZR1-mediated repression of OsYUC8-driven auxin biosynthesis modulates secondary cell wall formation to optimize flag leaf architecture, providing a genetic strategy for maximizing yield under high-density cultivation.

plant biology↗

bioRxiv2026

Neural control of respiration in Drosophila

Adaptive control of breathing is essential for life, yet the neural circuits that couple respiration to locomotion and internal physiological state remain poorly understood. Insects regulate gas exchange through spiracles: valve-like openings in the cuticle that allow oxygen uptake while minimizing water loss. We find that spiracle opening in Drosophila is dynamically matched to flight power and reduced by dehydration. We identify the motor neurons that innervate the spiracle muscles and show that their optogenetic activation closes all eighteen spiracles and rapidly limits flight power. Inhibitory interneurons transmit descending flight commands to the spiracle motor neurons, opening spiracles in proportion to metabolic demand. A parallel interoceptive pathway converges on the same interneurons to close the spiracles and suppress flight. Feedforward descending commands thus couple flight power to spiracle opening, while interoceptive feedback pathways close spiracles to balance oxygen supply against water loss. This compact circuit architecture may reflect a general solution for matching respiration to the competing demands of locomotion and water conservation.

neuroscience↗

bioRxiv2026

Hidden genetic diversity in 320 nearly-complete East Asian genome assemblies

East Asian populations, representing over 20% of the global population, remain critically underrepresented in human genomic studies, limiting our understanding of population-stratified genetic variation and its implications for health and disease. Here we present the first phase of the Asian Pan-Genome project (APG), comprising 320 nearly complete, fully phased haploid genome assemblies from 160 East Asian individuals. These assemblies achieve unprecedented quality, with an average contig N50 of 144.3 megabase pairs and an average quality value of 64.5. Leveraging these superior assemblies, we reveal previously uncharacterized diversity in human repeatome, including population-stratified patterns in centromere satellites and rDNA arrays. Compared to existing global human genome assemblies, the newly generated genomes supplement 152 million base pairs of novel sequences, 355 gene gains, 18,300 structural variation loci and 26 large euchromatic inversions missing from current human pangenomes. We perform population stratification analyses of structural variations, and further resolve the structural haplotypes of complex genomic regions such as Major Histocompatibility Complex and Survival Motor Neuron loci across global pangenomes, exemplifying tandem-duplicate and inversion-rich complex locus architectures in the human genome, respectively. This resource provides a critical foundation for human genetic studies, especially for East Asian populations, promoting more accurate variant discovery, reducing bias, and ultimately advancing the equity and efficacy of genomic medicine.

genomics↗

bioRxiv2026

The Proposed Bone Post-Arterial Type R Capillaries Resolve into Venous and Fatty Acid-Handling Endothelial Cells

Endothelial specialization is increasingly recognized as a fundamental regulator of tissue homeostasis, yet the cellular diversity of the skeletal vasculature remains incompletely resolved. Here, we integrate large-scale single-cell transcriptomics, cross-tissue comparisons, and imaging to comprehensively define endothelial heterogeneity across the skeleton. Our analyses demonstrate that the proposed post- arterial "type R" endothelial population is not a distinct endothelial subtype but instead comprises canonical venous endothelial cells and fatty acid-handling endothelial state. RNA velocity supports a venous continuum, while the proposed type R markers FMO2, and AQP7 lack both endothelial and skeletal specificity. The fatty acid-handling endothelial state, characterized by Lpl and Cd36 is conserved across multiple skeletal sites and non-skeletal tissues, indicating a general endothelial metabolic programme. Within bone, this endothelial state expands following high-fat diet and is suppressed during injury. Together, these findings redefine skeletal endothelial heterogeneity and establish the proposed type R population as part of a venous continuum.

cell biology↗

bioRxiv2026

Nectar chemistry reflects pollination strategies in alpine plant communities

Nectar is a primary floral reward, which can also deter non-specialist pollinators; yet, the role of complex nectar composition in plant-pollinator interactions and its relationship to other floral traits remain understudied, particularly in natural communities. We profiled the nectar metabolome of 43 co-occurring species in an alpine grassland to evaluate relationships among nectar chemistry, phylogeny, floral display traits and pollinator visitation. Field observations revealed a dominant bee vs fly visitation gradient. Several aggregated nectar traits tracked this gradient independently of plant phylogeny, indicating functional convergence: specifically, bee visitation was associated with higher nectar sucrose proportion, greater compound richness, and more divergent profiles of uncommon sugars. Nectar traits exhibited variable relationships to floral display traits, suggesting partial inter-trait phenotypic integration. Together, these findings indicate that detailed features of nectar composition, including phytochemical diversity, play a functional role in floral phenotypes, with previously unappreciated implications for plant-pollinator community ecology.

ecology↗