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Xu, X.

Publications and source records attributed to Xu, X..

At least 55 records · Page 3Linked to original sources

New genes play a prominent role in evolution of new sperm classes of Drosophila

The widespread and regulated production of infertile parasperm assisting fertilization of eusperm provides a compelling model for elucidating the mechanisms of cellular innovation and altruism. Here we identify two specific parasperm lineages in Drosophila pseudoobscura that are segregated in development from the eusperm lineage by their single-cell transcriptomes. Most X-linked genes, except for species-specific new genes, show testis-specific repressive epigenetic modifications and become downregulated upon meiotic entry, supporting meiotic X chromosome inactivation. Between sperm classes, nearly half of the known meiotic arrest genes and their downstream targets are differentially transcribed, with over 200 genes displaying a gradient of transcription levels correlated with that of tail lengths. New genes are overrepresented throughout the hierarchical regulatory network of sperm divergence and over 60% of them exhibit a new cell-level expression compared to their parental copies. These results together indicate that new genes play a prominent role in the emergence of low-cost parasperm that shield the eusperm until fertilization.

evolutionary biology↗

HnRNPAB-targeted antisense oligonucleotides ameliorate tau pathology and cognitive deficits by modulating Alzheimers disease-associated alternative splicing

Aberrant alternative splicing alters multiple disease-associated splicing events, including MAPT exon 10 inclusion linked to tau pathology, and thereby impacts Alzheimers disease (AD) progression. Heterogeneous nuclear ribonucleoprotein AB (hnRNPAB) functions as a splicing regulator, yet its roles in AD remain poorly defined. Here, we identified AB332, the full-length isoform of hnRNPAB, as a novel repressor of MAPT exon 10 inclusion. AB332 binds a conserved AAUAU motif and recruits RBMX and RBMXL1 through its RRM and glycine-rich domains to assemble a complex. Beyond MAPT, AB332 modulates a network of splicing events in multiple AD-associated genes, including STAG2, ApoER2, MCL-1, PICALM, and zDHHC7. Importantly, the exon 7-skipping isoform AB285 lacks these activities. Transcriptomic analysis of post-mortem brain tissues from AD patients revealed reduced expression of hnRNPAB, while selective downregulation of AB332 was confirmed in the hippocampus of 3xTg AD mice. We performed a systematic antisense oligonucleotide-tiling screen targeting hnRNPAB exon 7 and its flanking intronic regions, identifying ASO30 that specifically upregulated AB332 expression. In 3xTg AD mice, ASO30 restored hippocampal AB332 levels, reduced pathological tau phosphorylation, and rescued cognitive deficits. These findings define a molecular mechanism by which AB332 regulates AD-associated splicing events, thereby providing a therapeutic strategy targeting hnRNPAB for AD. GRAPHICAL ABSTRACT O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=79 SRC="FIGDIR/small/736008v1_ufig1.gif" ALT="Figure 1"> View larger version (23K): org.highwire.dtl.DTLVardef@621096org.highwire.dtl.DTLVardef@2f01b1org.highwire.dtl.DTLVardef@182e6forg.highwire.dtl.DTLVardef@190afd3_HPS_FORMAT_FIGEXP M_FIG C_FIG

molecular biology↗

circPMS1-mediated LIM protein scaffolding promotes cytoskeletal remodeling and melanoma metastasis

Circular RNAs (circRNAs) have been implicated in diverse biological processes and diseases such as cancer; however, their functional roles in tumor biology remain incompletely understood. Here, we identify circPMS1 as an aberrantly upregulated, pro-metastatic circRNA in melanoma. Overexpression and silencing studies revealed that circPMS1 promotes migration and invasion of non-transformed melanocytes and melanoma cells, enhances metastasis in xenograft models, and drives spontaneous dissemination and lymph node metastases in a genetically engineered melanoma mouse model. circPMS1 pro-metastatic activity depends on its circularization and is mediated by a putative secondary structure spanning the back-splice junction and the canonical start codon of the linear PMS1 mRNA. Proteomic analysis identified LIM domain proteins, including ABLIM1, LMO7, and PDLIM7, as circPMS1-bound factors. Mechanistic studies demonstrate that circPMS1 scaffolds these LIM proteins, enhancing their association with actin filaments inducing focal adhesion and cytoskeletal remodeling. This remodeling is associated with RhoA activity, and inhibition of the RhoA pathway attenuates circPMS1-induced migration. Together, these findings establish circPMS1 as a pro-metastatic circRNA that drives melanoma progression by scaffolding LIM domain proteins and regulating cytoskeletal dynamics and cell motility.

Cancer Biology↗

Dynamic gene gain and loss during the divergence of obligate biotrophic powdery mildew pathogens

Powdery mildew outbreaks can result in devastating crop losses across both horticultural and cereal crops. The obligate biotrophic fungi responsible (Erysiphaceae) depend entirely on living plant hosts for survival, extracting nutrients exclusively from living host tissue. Despite their impact, genomic resources for dicot-infecting powdery mildew fungi remain limited, restricting understanding of differentiation in the effector complements that underpin biotrophy across mildew lineages. To address this, we sequenced and assembled genomes from three independent samples each of Podosphaera leucotricha (apple mildew) and P. aphanis sensu lato (strawberry & raspberry mildew). These novel genomes were analysed alongside 44 publicly-available Erysiphaceae genomes to reveal striking inter-species differences in effectorome complements. P. leucotricha encoded the largest predicted effector complement of any powdery mildew pathogen sequenced to date, with major expansions in RALPH and EKA effector families. By contrast, the closely related P. aphanis carried a comparatively small effector repertoire. Together, these data challenge the prevailing view that effector expansion is restricted to monocot-infecting mildews. We observed that the divergence of powdery mildew genera is associated with the contraction of gene families, consistent with a stepwise loss of genes. This pattern was also reflected in the loss of genes that are typically conserved across ascomycete fungi. Taken together our findings highlight the contrasting impact that biotrophic adaptation has had on pathogen genomes, namely the convergent loss of conserved fungal genes alongside the diversification of pathogen effectoromes in response to host immune landscapes.

plant biology↗

Osteocyte Perilacunar/canalicular Remodeling (PLR) Drives Spatially Heterogeneous Lacunar Remodeling During and After Lactation

BackgroundPregnancy and lactation impose substantial demands on maternal calcium homeostasis, leading to pronounced skeletal remodeling during lactation followed by recovery after weaning. Although bone mass is largely returned at the tissue level after weaning, it remains unclear whether osteocyte-level remodeling exhibits a similarly reversible pattern. Osteocytes regulate mineral mobilization through perilacunar/canalicular remodeling (PLR), which is elevated during lactation. However, its spatial and temporal regulation in response to reproduction remains poorly defined. Objective/HypothesisThis study aims to determine whether PLR-regulated lacunar remodeling during reproduction varies with osteocyte location and relative age. We hypothesized that osteocyte PLR-mediated lacunar change is spatially heterogeneous during lactation, varies with osteocyte location and relative age, and may persist after weaning. MethodsFemale wild-type (WT) and osteocyte-specific PTH/PTHrP receptor knockout (cKO) mice were studied across reproductive stages. Longitudinal in vivo DXA and CT were used to assess skeletal changes. Sequential fluorochrome labeling tracked mineral dynamics and defined osteocyte relative age. Osteocyte PLR activity was evaluated by MMP13 immunohistochemistry. Lacunar-canalicular structure (LCS) was assessed using Ploton silver nitrate staining, and spatially resolved lacunar morphology was quantified using high-resolution backscattered scanning electron microscopy (bSEM). ResultsAt the tissue level, reproduction induced distinct skeletal responses, characterized by reversible cortical bone loss and persistent trabecular deterioration. Cortical bone loss during lactation was spatially asymmetric and confined to the posterior cortex. Fluorochrome labeling further resolved surface-specific remodeling patterns during reproduction, including endocortical resorption at the posterior cortex and sustained deposition at anterior endocortical and posterior periosteal surfaces. At the cellular level, osteocyte PLR activity increased during lactation in WT mice and returned after weaning, whereas no changes were observed in cKO mice. Consistently, lacunar size increased during lactation and returned toward baseline after weaning in WT mice but remained unchanged in cKO mice. Spatially resolved analysis demonstrated that lacunar remodeling was heterogeneous across cortical thickness. At the anterior cortex, lacunar enlargement occurred near the endocortical surface during lactation and was reversible after weaning. In contrast, at the posterior cortex, lacunar enlargement occurred near the periosteal surface and persisted after weaning. These spatial patterns corresponded to cortical regions enriched with newly formed osteocytes, whereas pre-existing osteocytes exhibited minimal changes. This spatial heterogeneity was absent in cKO mice. ConclusionOsteocyte PLR-mediated lacunar remodeling during reproduction is spatially heterogeneous and varies with osteocyte location and relative age. These findings demonstrate that recovery at the tissue level does not necessarily extend to the osteocyte microenvironment and identify osteocyte PLR-mediated lacunar remodeling as a spatially structured and potentially persistent component of reproductive skeletal adaptation. Together, these results highlight a previously unrecognized layer of maternal skeletal health.

bioengineering↗

Spatiotemporal Cascade of AP1/CCA1-TOC1 Module Gates Stem Development

Stem development is crucial in plant vertical architecture and overall crop improvement. The molecular mechanisms underlying the initiation and circadian growth of stem remain still enigmatic. Here, we demonstrate that APETALA1 (AP1) spatially initiates circadian stem growth through a noncell-autonomous role of TIMING OF CAB EXPRESSION1 (TOC1) emanating from the floral meristem to inflorescence meristem in Arabidopsis thaliana. Mechanistically, AP1 interacts with and recruits CIRCADIAN CLOCK-ASSOCIATED1 (CCA1) to associate TOC1. Dynamic formation of the AP1-CCA1 complex is crucial for maintaining the circadian rhythmicity and expression of TOC1. Tissue-specific expression of TOC1 in floral meristems rescues the developmental defects of toc1 mutants at both functional and transcriptional levels. Furthermore, TOC1 directly activates the circadian expression of pectin methylesterase gene family, which is critical for its role in stem development. AP1 homologs regulate circadian stem elongation and plant height in wheat and rice, underscoring the conserved mechanism across flowering plants. Our findings uncovered a spatiotemporal regulatory cascade gating stem development and identified candidate genes for crop improvement.

plant biology↗

Plant growth forms shaping biodiversity patterns can guide conservation planning on the Qinghai-Tibet Plateau

Plant growth forms effectively reflect profound evolutionary adaptations that underpin ecosystem functioning; however, how their biogeographic disparities influence conservation prioritization remains poorly understood. We here integrate a comprehensive phylogeny with high-resolution distribution data for 14,468 vascular plant species across the Qinghai-Tibet Plateau, showing that growth-form identity decouples the spatial patterns of taxonomic and phylogenetic diversity, with distinct forms exhibiting marked differences in geographic range sizes and elevational optima (2,200-3,300 m). Although herbs dominate plant assemblages across spatial scales, their proportional abundance decreases along a northwest-to-southeast aridity gradient, yielding to structurally complex, non-herbaceous forms in humid, species-rich regions. Consequently, priority conservation areas derived for individual growth forms exhibit low spatial similarity. Despite this divergence, we identify trees and climbers as highly effective umbrella growth forms: prioritizing these functional groups captures [≥]75% of the multidimensional diversity of all other growth forms within a minimal spatial footprint. Our findings demonstrate that accounting for growth-form-based functional identity is essential for maximizing conservation efficacy, providing a scalable framework for biodiversity hotspots worldwide.

ecology↗

The Role of Osteocyte Estrogen Receptor β in Bone Mass Maintenance and Tibial Stiffness Following Sex Hormone Withdrawal in Male and Female Mice

Sex hormones are essential regulators of skeletal maintenance, but the cell-specific mechanisms by which osteocytes mediate the skeletal consequences of sex hormone deficiency remain incompletely understood. Osteocyte estrogen receptor {beta} (Ot-ER{beta}) has been implicated in sex-specific regulation of bone mass, particularly in male mice, yet its role in coordinating bone morphology and mechanical competence following sex hormone withdrawal is unclear. In this study, male and female mice with osteocyte-targeted ER{beta} deletion (ER{beta}-dOT) and littermate controls were subjected to orchiectomy (ORX), ovariectomy (OVX), or sham surgery at 20 weeks of age. Four weeks later, vertebral and tibial bone morphology were assessed by micro-computed tomography, and tibial mechanical behavior was evaluated using strain gauge-calibrated, microCT-based finite element modeling. ORX induced substantial cancellous bone loss in the lumbar vertebra and proximal tibia of male mice regardless of genotype. In cortical bone, however, ORX reduced tibial cortical area and minimum moment of inertia in male littermate controls, whereas these cortical deficits were attenuated in male ER{beta}-dOT mice. Consistent with these morphological changes, ORX increased finite element-predicted peak tensile and compressive strains in tibial cortical and cancellous compartments and reduced whole-bone stiffness in male controls, but these mechanical deteriorations were largely prevented by Ot-ER{beta} deletion. In contrast, OVX produced modest changes in female tibial cortical geometry and increased cancellous bone strains, but these responses were not strongly dependent on Ot-ER{beta}. Together, these findings reveal that Ot-ER{beta} mediates the skeletal response to sex hormone withdrawal in a sex- and compartment-dependent manner. Specifically, Ot-ER{beta} contributes to ORX-induced deterioration of tibial cortical morphology and mechanical competence in male mice, whereas it is largely dispensable for OVX-induced skeletal changes in female mice. This work highlights osteocyte ER{beta} as a sex-specific regulator linking hormonal status, bone morphology, and load-induced strain environments.

bioengineering↗

Lamin A/C coordinates nuclear mechanics, chromatin architecture, and transcriptional homeostasis in skeletal muscle in vivo

The nuclear lamina provides mechanical integrity to the eukaryotic nucleus and organizes lamina-associated chromatin domains that are important for chromatin architecture and gene-expression regulation. Lamin A/C, a major component of the nuclear lamina, is disrupted in hereditary laminopathies and has also been implicated in aging-associated nuclear dysfunction. Although the mechanical role of Lamin A/C has been extensively studied in vitro, particularly in monolayer cell culture and isolated nuclei, its role in maintaining nuclear mechanics and chromatin organization in intact tissues remains incompletely understood. Here, we investigated how partial and complete Lamin A/C disruption affects nuclear shape, chromatin architecture, intranuclear mechanics, and gene expression in vivo. Across multiple murine tissues, Lamin A/C deficiency did not cause a generalized collapse of nuclear shape or gross tissue architecture. Instead, Lamin A/C disruption preferentially altered chromatin architecture in mechanically stiff tissues, including skeletal muscle and heart. Using live in vivo deformation microscopy during controlled hindlimb muscle stimulation, we quantified real-time multiscale deformation of skeletal muscle tissue and nuclei. These measurements revealed reduced effective nuclear stiffness and altered load sharing between euchromatin-rich and heterochromatin-rich domains after Lamin A/C loss. Super-resolution imaging further showed that partial and complete Lamin A/C disruption uncoupled H3K9me3 from DAPI-dense heterochromatin, indicating a spatial disruption of repressive chromatin organization. Exploratory ATAC-seq suggested increased chromatin accessibility in heterozygous muscle, whereas RNA-seq showed that complete Lamin A/C loss caused broad myopathic transcriptional dysregulation while partial loss preserved a near-wild-type transcriptomic state. Integrated analysis identified HDAC2 as a candidate mechanosensitive compensatory node that may help buffer gene expression after partial Lamin A/C disruption. Together, these results establish Lamin A/C as an in vivo coordinator of nuclear mechanics, heterochromatin organization, and transcriptional homeostasis in skeletal muscle.

cell biology↗

Trichome acylsugar defenses are equally effective against leaf-mining and free-living insects

Trichomes are epidermal projections, crucial components of plant defense systems. Whether these epidermal defenses are effective against leafminers, which infest the internal mesophyll layers, remains unclear. Using the devasting invasive tomato pest, Phthorimaea absoluta (tomato leafminer), and the trichome-rich wild tomato, Solanum pennellii, we demonstrate that trichome produced acylsugars effectively inhibit the growth of endophagous P. absoluta larvae feeding inside leaves. High spatial resolution leaf- and frass-metabolite analysis by MALDI-MSI and Stimulated Raman Scattering microscopy revealed that trichome-synthesized acylsugars are translocated into the mesophyll tissues when larvae infest leaves. We identified an ATP-binding cassette (ABC) transporter, SpABCB5, as the mediator of this translocation and as an essential component of defense against leafminers. These data reveal that epidermal trichomes not only defend against free-living (ectophagous) herbivores through direct contact or rapid deposition of chemical defenses onto leaf surfaces, but also defend against endophagous leafminers by rapidly depositing chemical defenses into internal tissues. By delivering mines against leaf miners, trichomes offer new avenues for breeding crops with resistance to leafminers.

plant biology↗

BRCA1 promotes homologous recombination through separable DNA and RAD51 binding activities within its disordered region.

The breast and ovarian tumor suppressor BRCA1 heterodimerizes with BARD1 to promote DNA double-strand break repair by homologous recombination (HR) and to protect stressed DNA replication forks against nuclease attack. The large, intrinsically disordered central region of BRCA1 harbors binding sites for DNA and multiple repair factors, but its lack of stable structure has hindered mechanistic dissection of these activities. Using biochemical mapping and NMR spectroscopy, we delineate the DNA binding and RAD51 interaction interfaces within this region and construct separation-of-function mutants that selectively ablate each activity. Both DNA binding and RAD51 interaction are required for BRCA1-BARD1 to promote RAD51-mediated DNA strand invasion, and DNA binding also contributes to BLM-DNA2 end resection. These findings provide mechanistic insights into how individual ligand binding activities within BRCA1 contribute to genome maintenance.

biochemistry↗

Circadian misalignment underlies immune escape in breast cancer

Circadian regulation shapes tissue physiology, yet how it organizes cellular and molecular dynamics within the tumor microenvironment (TME) and influences tumor immunity remains unclear. Using temporal single-nucleus multiomic profiling of mouse breast tumors, we uncovered extensive circadian programs that are both cell-type-specific and shared across the TME, governing proliferation and immune responses. Notably, cancer epithelial cells exhibited global acrophase misalignment relative to immune populations. This intercellular desynchrony manifests as temporal decoupling between tumor proliferation and immune activation, discordant antigen presentation and T cell recognition with intrinsic activation-exhaustion overlap in T cells, and asynchronous PD-1/PD-L1 oscillations that sustain checkpoint-mediated suppression. Similar patterns were observed in human triple-negative breast cancer (TNBC). Together, these findings establish intercellular circadian misalignment as a mechanism of tumor immune evasion and position the circadian architecture of the tumor-immune ecosystem as a previously underappreciated determinant of tumor development and therapeutic response. HIGHLIGHTSO_LISingle-cell multiomics maps circadian regulation of tumor-immune programs. C_LIO_LICircadian regulation in cancer epithelial cells is misaligned with immune cell populations. C_LIO_LITumor-immune temporal misalignment undermines antitumor immunity. C_LIO_LICircadian misalignment in human TNBC suggests relevance for immunotherapy timing. C_LI

cancer biology↗

Antibody treatment targeting nitrated alpha-synuclein counteracts protein spreading pathology

-Synuclein nitration is a prominent post-translational modification in Parkinsons disease, but whether nitrated -synuclein merely reflects oxidative stress or actively contributes to pathology remains unclear. Here, we generated and characterized 6G6, an antibody selective for Tyr39-nitrated -synuclein, and tested whether targeting this modified -synuclein species affected pathology in different mouse models of -synuclein aggregation and spread. In two models of -synuclein overexpression targeting medullary vagal neurons, oxidative stress was induced by either exposure to the herbicide paraquat or transgenic heterozygous expression of the Gba1-L444P mutation. Both conditions were characterized by robust -synuclein spreading that was markedly counteracted by 6G6 administration. A third model consisted of an injection of -synuclein fibrils into the striatum of -synuclein-overexpressing mice. In this model, treatment with 6G6 protected against fibril-induced aggregate pathology and ensuing degeneration of nigral dopaminergic neurons. In a pilot human study, CSF levels of Tyr39-nitrated -synuclein were measured and found increased in Parkinson patients as compared to controls. These findings identify Tyr39-nitrated -synuclein as a pathogenic, therapeutically targetable -synuclein species linking oxidative/nitrative stress to PD pathological processes.

neuroscience↗

Novel Muscle-Tropic AAV Capsids with Dramatically Enhanced Transduction and Safety Profiles in Non-Human Primates

Adeno-associated virus (AAV) gene therapy holds immense promise for treating muscular dystrophies, yet its efficacy and safety are constrained by the suboptimal tissue tropism of natural serotypes. Here, we employed the REACH platform, which combines rational design and directed evolution, to engineer muscle targeting vectors. Systemic administration in non-human primates (NHPs) revealed that lead candidate M1 mediates a >10-fold increase in skeletal muscle transduction compared to the AAV9 and 2-3 fold higher than MyoAAV, while concurrently achieving a remarkable 183-fold reduction in liver distribution. Furthermore, M1 exhibited significant de-targeting from key off-target tissues, including dorsal root ganglia (11 fold), lung (27 fold), spleen (2 fold), and kidney (2 fold). These findings demonstrate that the REACH platform can generate AAV capsids with simultaneously enhanced muscle tropism and favorable safety profiles, addressing a critical bottleneck in muscle-directed gene therapy.

bioengineering↗

Genomic Decoding of Specialized Aromatic Hydrocarbon Degradation in Mangrove-Derived Gordonia sp. B7 2

Petroleum pollution has increased worldwide, driving the search for microorganisms with efficient hydrocarbon-degrading capabilities. Here, we report a novel bacterium, Gordonia sp. B7-2, isolated from mangrove sediments in Hainan, China. Phylogenetic analysis based on the 16S rRNA gene and whole-genome sequences, together with digital DNA-DNA hybridization and average nucleotide identity values, supported its classification as a new species within the genus Gordonia. The complete genome of strain B7-2 consists of a single circular chromosome of 5.39 Mb with a G+C content of 65.99%, and encodes 4,887 protein-coding genes. Genomic annotation revealed a complete pathway for aromatic hydrocarbon degradation, including genes encoding protocatechuate 3,4-dioxygenase and biphenyl-2,3-diol 1,2-dioxygenase, whereas genes involved in the initial oxidation of alkanes were absent. Consistent with these genomic predictions, strain B7-2 degraded 64.33% of crude oil (300 mg/L) within 28 days, with rapid degradation during the initial 14 days, followed by a slower phase thereafter, reflecting the dynamics of complex hydrocarbon mixtures. Together, these results demonstrate that strain B7-2 is specialized for the degradation of aromatic hydrocarbons and highlight its potential for targeted petroleum bioremediation. IMPORTANCEMangrove ecosystems are highly vulnerable to petroleum contamination, yet the microorganisms responsible for hydrocarbon turnover in these environments remain poorly characterized. This study describes a new bacterial species, Gordonia sp. B7-2, that exhibits a strong metabolic specialization for aromatic hydrocarbon degradation. Unlike many known oil-degrading bacteria that preferentially utilize alkanes, strain B7-2 targets aromatic components of crude oil, which are among the most persistent and toxic fractions.Its ability to efficiently degrade crude oil highlights its potential in the bioremediation of contaminated coastal environments and expands our understanding of microbial contributions to hydrocarbon cycling in mangrove sediments

microbiology↗

Decoding Immune Reconstitution Failure in People Living with HIV through Single-cell Genomics

Immune non-responders (INRs), a subset of people living with HIV (PLWH), fail to achieve full immune reconstitution and remain at increased risk of morbidity, mortality, and non-AIDS-related illnesses. As the mechanisms underlying this impaired immune recovery remain poorly understood, we performed single-cell multi-omics profiling on peripheral blood mononuclear cells from 43 INRs, 47 immune responders and 53 healthy donors. Our dataset comprises 2,744,009 transcriptomes and 1,226,658 chromatin-accessibility profiles across 58 identified immune cell types. INRs exhibited markedly elevated inflammatory signaling, increased apoptotic activity, and dysregulation of immune-activating ligand-receptor interactions. Additionally, we identified 2,996 interaction cis-eGenes and 5,938 cis-caPeaks, and validated key cell type-specific cis-xQTL effects associated with immune reconstitution failure. Furthermore, we identified 3,551 sc-eQTLs and 872 cell-state interaction eQTLs (ieQTLs) in CD4+ T cells. A genotype-specific upregulation of OAS3 in INRs, likely regulated by STAT1, was identified based on these results. We developed scPRISM (single cell Predictive Reconstitution Immune Status Model), a multi-modal framework that integrates scRNA-seq and scATAC-seq data to perform the dual tasks of differentiating disease states and predicting gene expression from chromatin accessibility, thereby deciphering the cell type-specific cis-regulatory basis of the disease. Our study delineates the transcriptional and epigenomic landscape of immune dysregulation in INRs and provides new genetic insights into HIV-associated immune reconstitution failure. These findings offer a foundation for developing biomarkers and precision therapies to restore immune function in PLWH.

genetics↗

Prefrontal mechanisms of goal progress inference and monitoring in macaque monkeys

Primates pursue goals over extended periods and over multiple steps. The ability to track progress and its rate is critical for such pursuit, yet the neural mechanisms of this tracking are unclear. We recorded single-unit activity from macaque midcingulate cortex (MCC) and lateral prefrontal cortex (LPFC) whilst animals worked for immediate rewards and checked a gauge showing progress towards a larger reward. MCC expressed a temporally extended progress rate signal linked to the long timescale neurons in the region. LPFC expressed progress rate only when inferences on that property were required. In MCC, independent feedback-valence information was also preserved, enabling both readout of work success and rate-specific progress updating. An RNN trained under the same constraints showed that progress rate representations emerge spontaneously, and are critical for tracking goal progress. These results demonstrate a frontal mechanism for inferring and predicting goal progress by extracting progress rate information.

neuroscience↗

Patient-specific "Physical Twin" artery-on-chip platform reveals complex flow-dependent VWF mechanobiology and guides personalized antithrombotic therapy

Ischemic stroke triggered by carotid atherosclerosis remains unpredictable because the thrombosis embolization is governed by patient-specific vascular geometry and hemodynamics that cannot be recapitulated in conventional models. Here, we engineered "Physical Twin" artery-on-chip platforms that reproduce individualized carotid anatomy with humanized subendothelial matrix composition and arterial endothelial phenotype under physiological flow patterns. We then established thrombotic microenvironments following laser-induced injury. Computational fluid dynamics-guided experiments across distinct patient geometries reveal that local shear dictates a mechanobiological hierarchy: high-shear bifurcations ([~]3,000 s-{superscript 1}) produce von Willebrand factor (VWF) A1-dependent thrombi suppressible by conformationally sensitive inhibitors, whereas low-shear stenoses generate fragile aggregates where VWF-integrin IIb{beta} coupling governs embolization overgrowth. Pulsatile flow suppresses thrombotic growth independent of mean shear. Molecular dynamics simulations reveal why conformationally sensitive nanobodies (caplacizumab) outperform shear-independent aptamers (ARC1172) in high-shear bifurcation flow zones. This Physical Twin platform provides a mechanistic blueprint for geometry-informed, personalized antithrombotic therapy selection.

bioengineering↗