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Zhang, M.

Publications and source records attributed to Zhang, M..

At least 109 records · Page 6Linked to original sources

A Symmetric Systemic Challenge Elicits a Right-Biased Response Mediated by Vasopressin Signaling

Bilaterian animals exhibit operational (functional) asymmetry--population-level, directional left-right differences in physiology and behavior, including responses to spatially symmetric environmental challenges. Whether such symmetry-to-asymmetry conversion can be driven at the systems level by neurohormonal regulators remains unclear. Here we tested whether a spatially symmetric neuroendocrine challenge--water deprivation (WD)--can elicit a directional left-right physiological response in rats using hindlimb postural asymmetry (HL-PA), a binary readout that quantifies left- versus right-sided hindlimb flexion. Twenty-four hours of WD induced robust HL-PA with right hindlimb flexion, revealed under anesthesia. The asymmetry persisted after complete thoracic spinal cord transection, suggesting that humoral signaling, rather than descending neural commands, may maintain the postural bias. Because dehydration recruits the hypothalamic-neurohypophysial arginine vasopressin (AVP) system, we next tested AVP receptor involvement. Both a V1B antagonist (SSR-149415) and a V1A/V2 antagonist (conivaptan) abolished WD-induced HL-PA, supporting an AVP-dependent mechanism that likely operates at least two anatomical sites. AVP signaling may involve pituitary V1B-dependent endocrine output and spinal V1A actions; consistent with the latter, expression of AVP V1A receptors is right-biased in lumbar spinal cord. Together, these findings identify WD as a symmetric systemic challenge capable of imposing a directional peripheral set-point, and implicate vasopressin signaling in symmetry breaking and left-right physiological regulation. Visual summary O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=133 SRC="FIGDIR/small/708998v1_ufig1.gif" ALT="Figure 1"> View larger version (36K): org.highwire.dtl.DTLVardef@10d6b3corg.highwire.dtl.DTLVardef@1fb4b5aorg.highwire.dtl.DTLVardef@11003c0org.highwire.dtl.DTLVardef@66671c_HPS_FORMAT_FIGEXP M_FIG C_FIG

neuroscience↗

Global O-GlcNAcome Identifies O-GlcNAcylated Proteins Regulating Oligodendrocyte Precursor Cells Differentiation

Oligodendrocyte precursor cells (OPCs) differentiate into myelinating oligodendrocytes to form the myelin sheaths essential for neural function, a process frequently compromised during aging and in diseases like multiple sclerosis. However, the regulatory landscape of myelination remains incompletely understood. Here, we perform a comprehensive proteomic analysis of the O-GlcNAcome in postnatal day 0 mouse OPCs, identifying 165 O-GlcNAcylation sites across 118 proteins. These proteins are mostly nuclear and characterized by single-site modifications. Comparative analysis identifies 74 novel sites and 22 proteins uniquely O-GlcNAcylated in OPCs. Molecular docking suggestes that O-GlcNAcylation might act as a dynamic regulator of OPC differentiation. Notably, global O-GlcNAcylation levels increase during the OPC-to-oligodendrocyte transition. By integrating our findings with multiple sclerosis-related transcriptomic and proteomic datasets, we identify candidate proteins linking O-GlcNAc dysregulation to demyelination. Among these, Vimentin (Vim) exhibits a pronounced age-dependent discrepancy between decreased protein levels and elevated mRNA expression during differentiation. We validate Threonine 35 and 63 as key O-GlcNAcylation sites on Vimentin. Functional assays confirm that blocking Vimentin O-GlcNAcylation enhance the OPC differentiation. Collectively, our study establishes the first O-GlcNAc landscape for OPCs and suggests O-GlcNAcylation as a pivotal regulator for OPC differentiation.

neuroscience↗

Not all mantra meditations are equal: Emergence of divergent alpha oscillatory dynamics across mantras

The study of contemplative practices has evolved into a mature field, yet current taxonomies tend to classify all mantra-based meditation approaches as a single category, overlooking potentially different neural states induced by different mantras or different instructions. To address this gap, we conducted a study of 50 novice subjects practicing two types of mantra-based meditation over a six week period to evaluate changes in Electroencephalography (EEG) during and after meditation. Participants were randomly assigned to meditating with the Hare Krishna (HK) and Sa-Ta-Na-Ma (SA) mantras. Using spectral parameterization, we assessed the effects of each type of meditation on individual alpha power (IAP), individual alpha frequency (IAF) and center of gravity (CoG). The results revealed marked differences in alpha dynamics between the two practices. On the one hand, the HK group exhibited widespread IAP decrease and an IAF/CoG increase during mantra meditation that was maintained during rest after the meditation, which became more pronounced after training in the HK meditation. On the other hand, the SA group showed a localized IAP reduction during meditation and significant reduction of IAF during meditation after training. We suggest that the higher cognitive demands of HK induce a more activating, attentionally focused state, whereas SA promotes a more relaxed state. Additional psychological data show that both meditation groups had reduction in stress. Thus, these findings challenge the monolithic classification of mantra meditation and highlight the importance of differentiating practices according to their mechanisms, particularly for their targeted application in mental health contexts.

neuroscience↗

Targeting phosphodiesterase 10A disrupts MAPK signaling pathways in the tumor microenvironment to unleash antitumor immunity

Phosphodiesterase 10A (PDE10A), a cyclic nucleotide-degrading enzyme, is overexpressed in various human cancers. While PDE10A inhibition using small-molecule inhibitors or gene silencing suppresses tumor growth in xenograft models, its precise mechanism of action and immunological impact remain unclear. Here, we report that ADT-030, a novel PDE10A inhibitor, exhibits potent cytotoxicity against a broad range of murine tumor cell lines. ADT-030 is orally bioavailable and effectively suppresses tumor growth across multiple syngeneic mouse models. Notably, its efficacy is diminished in immunodeficient mice or upon CD8+ T cell depletion, highlighting a critical dependence on host immunity. The immunostimulatory properties of ADT-030 are further supported by its ability to induce immunogenic tumor cell death and promote dendritic cell (DC) maturation, its reliance on Batf3-expressing DCs to elicit antitumor CD8+ T cell response, and its synergy with anti-PD-1 therapy. Comprehensive immune profiling in the 4T1 breast cancer model, both in orthotopic and metastatic settings, revealed that ADT-030 selectively reduces myeloid-derived suppressor cells (MDSCs) while normalizing the immune landscape within the tumor. Mechanistically, ADT-030 disrupts multiple components of the mitogen-activated protein kinase (MAPK) signaling network in both tumor cells and MDSCs, leading to induction of apoptosis in these populations. These findings highlight the multi-faceted impact of PDE10A inhibition as a therapeutic strategy that not only disrupts tumor-intrinsic oncogenic signaling to inhibit tumor progression but also reshapes the tumor immune microenvironment to unleash antitumor immunity.

immunology↗

Redox-activated induction of Warburg-type metabolism in the adult heart

Proliferating cells rewire glucose metabolism away from oxidative ATP production towards glycolysis and anabolic branch pathways (the Warburg effect). In contrast, the contractile function of terminally differentiated cardiomyocytes in the heart critically depends upon mitochondrial ATP generation. Adult cardiomyocytes are largely non-proliferative but undergo hypertrophy in response to increased heart workload. A fundamental question in the field is how cardiac metabolism is modified to balance competing energetic and anabolic demands. We previously reported that the redox-signalling H2O2-generating enzyme, NADPH oxidase 4 (NOX4), facilitates compensated cardiac function in hearts undergoing hypertrophic remodelling. Here, we show that NOX4 induces Warburg-type reprogramming of glucose metabolism in the healthy heart, with increased flux into the pentose phosphate, serine and nucleotide biosynthetic pathways. Using an integrated multiomics approach, we uncover a NOX4-regulated network involving interplay between direct transcriptional activation of metabolic genes via NRF2 [aka NFE2L2] and ATF4 and a broader epigenetic regulation. This reprogramming of glucose intermediary metabolism along with previously reported NOX4-mediated enhancement of fatty acid oxidation may serve to optimally support the dual requirements of increased energy demand and remodelling in the heart. Our findings identify a novel paradigm for redox-regulated Warburg-type metabolic reprogramming in the terminally differentiated heart.

physiology↗

MG53 Protects Against Intestinal Inflammation by Inhibiting NLRP3 Inflammasome Activation

Background and ObjectivesInflammatory bowel disease (IBD) involves dysregulated immune responses and chronic intestinal inflammation. The nod-like receptor pyrin domain-containing 3 (NLRP3) inflammasome plays a critical role in IBD pathogenesis, but regulatory mechanisms remain not fully understood. Mitsugumin 53 (MG53, also known as TRIM72), originally identified as a critical membrane repair protein, has emerged as a novel regulator of inflammatory processes. To investigate the protective role of MG53 in colitis and elucidate its mechanisms in regulating NLRP3 inflammasome activation in IBD. MethodsWe used dextran sodium sulfate (DSS)-induced colitis models comparing MG53 knockout (MG53-/-) and wild-type (WT) mice, assessing disease severity, MG53 tissue uptake, and therapeutic effects of recombinant human MG53 (rhMG53). In vitro studies examined rhMG53s effects on NLRP3 inflammasome activation, caspase-1 cleavage, interleukin-1{beta} (IL-1{beta}) secretion, and MG53-NLRP3 interactions. ResultsMG53-/- mice showed more severe colitis with increased weight loss, higher disease activity scores, shortened colons, and greater inflammation. DSS treatment induced the accumulation of circulating MG53 in inflamed colonic tissue. rhMG53 administration ameliorated colitis severity in MG53-/- mice and dose-dependently suppressed NLRP3 inflammasome activation in vitro. MG53 interacted with NLRP3 and reduced apoptosis-associated speck-like protein containing a CARD (ASC) speck formation and NLRP3 oligomerization without affecting upstream signaling or NLRP3 stability. ConclusionMG53 is a physiological regulator of NLRP3 inflammasome activation that protects against colitis, suggesting therapeutic potential for IBD.

immunology↗

Hypothalamic asymmetry in hemisphere-specific neuroendocrine signaling

Brain lesions classically cause contralateral sensorimotor and postural deficits, attributed to the decussation of descending neural pathways. However, recent findings reveal that, beyond neural mechanisms, contralateral effects can also be mediated by the neuroendocrine system via humoral pathways. This raises the possibility that the brain regulates left- and right-sided peripheral processes through hypothalamic neurohormones released into the bloodstream. For such spatially targeted endocrine signaling to occur, hemisphere-specific neural activity must be encoded into side-specific hormonal output--requiring a lateralized organization of hypothalamic neuroendocrine systems. Here, we report molecular asymmetries in the rat hypothalamus that support this mechanism. Transcriptomic analysis revealed asymmetric expression of eleven neurohormonal genes, including Gnrh1, Cck, and Trh, along with distinct left-right side-specific gene co-expression networks. Chemogenetic stimulation of Arg-vasopressin neurons in vasopressin-hM3Dq-mCherry transgenic rats produced generalized changes in these networks--predominantly in the right hypothalamus--suggesting that hypothalamic neurohormonal circuits function as integrated, lateralized ensembles. Stereological analysis revealed asymmetric coordination of vasopressin neurons within the paraventricular nucleus, with the left rostral region decoupled from the right rostral and caudal subregions. Functionally, gonadotropin-releasing hormone, cholecystokinin-8, and thyrotropin-releasing hormone--administered intracisternally in rats with complete spinal cord transection--elicited side-specific peripheral responses, measured as hindlimb postural asymmetry in a binary left-right output model. These neurohormonal effects were therefore transmitted via the humoral route. These findings suggest that multiple hypothalamic neurohormones and their integrated networks are asymmetrically organized, and that their lateralization may be necessary for hemisphere-specific hormonal regulation of peripheral systems.

neuroscience↗

Accurate quantification of canine mitochondrial DNA copy number and its evaluation as a biomarker of brain injury

Acute brain injury is challenging to manage in veterinary medicine, with limited validated means of prognostication currently available. The brain is rich in mitochondrial content and contains thousands of copies of mitochondrial DNA (mtDNA) per cell. We hypothesized that brain cell loss following acute brain injury may result in release of mtDNA into the systemic circulation. To investigate this, mtDNA-CN was measured in blood (n=4-6/group) and cerebral cortex (n=1/group) samples from dogs with and without brain injury using absolute quantification by real-time qPCR. By filtering out regions with homology to nuclear mitochondrial insertion sequences (NumtS) and repetitive regions, oligonucleotide primers were designed to the canine mitochondrial and nuclear genomes. In controls, blood mtDNA-CN ranged from 98 to 288 (mean 193{+/-}72), in cases of brain injury, there was a non-significant trend for higher mtDNA-CN, ranging from 163-453 (mean 244{+/-}106). As expected, cerebral cortex contained higher mtDNA-CN than the blood. In a single case with serial sampling, mtDNA-CN increased five days post-injury. We present for the first time an assay to accurately quantify mtDNA-CN in canine samples, with potential as a biomarker for acute brain injury in veterinary practice. Simple SummaryThis work describes a novel assay to accurately measure absolute levels of canine mitochondrial DNA copy number (mtDNA-CN) in biological samples. We describe the range of mtDNA-CN in canine blood and show pilot data suggesting that blood mtDNA-CN should be evaluated as a potential biomarker of acute brain injury.

molecular biology↗

Physically Grounded Generative Modeling of All-Atom Biomolecular Dynamics

Predicting the kinetic pathways of biomolecular systems at all-atom resolution is crucial for understanding protein function and drug efficacy, yet this task is hindered by the immense computational cost of conventional molecular dynamics (MD) simulations. While deep learning has revolutionized static structure prediction and equilibrium ensemble sampling, simulating the kinetics of conformational transitions remains a critical challenge. We introduce BioKinema, a physically grounded generative model that predicts continuous-time, all-atom biomolecular trajectories at a fraction of the cost of traditional simulations. In particular, BioKinema utilizes a spatial-temporal diffusion architecture motivated by the exponential decay of correlations characteristic of Langevin dynamics, and is explicitly trained to generate trajectories with the correct kinetics and thermodynamics. It employs a hierarchical forecasting-and-interpolation strategy to overcome the error accumulation that often plagues long-horizon generation. Through extensive validation, we demonstrate that BioKinema generates physically stable and dynamically accurate trajectories suitable for rigorous downstream analysis. For protein systems, it reproduces the equilibrium thermodynamics of the conformational ensemble and the underlying kinetics. For protein-ligand complexes, it successfully elucidates mechanisms such as ligand-driven conformational changes and allosteric interactions. Furthermore, BioKinema leverages enhanced sampling data to predict rare kinetic events, emerging as a powerful tool for estimating ligand unbinding pathways. Collectively, these results establish BioKinema as a computationally efficient complement to MD simulations that bridges the gap between static structure and dynamic function, enabling high-throughput exploration of the kinetic landscape for structural biology and drug discovery.

bioinformatics↗

Functional activation reveals a repressor-gated fourth type VI secretion system in clinical Pseudomonas aeruginosa

Pseudomonas aeruginosa is a major opportunistic pathogen in which the type VI secretion system (T6SS) contributes to interbacterial competition and virulence. While most strains encode three T6SSs, we here functionally characterize a fourth system (H4-T6SS) in a clinical P. aeruginosa isolate. The H4-T6SS gene cluster is transcriptionally silent under laboratory conditions. By promoter rewiring, we demonstrate that the H4-T6SS assembles a contractile machine and mediates effector secretion and robust inter- and intraspecific antagonism. We identify a dominant pore-forming effector and its secretion pathway and a silent yet conserved nuclease effector. Genetic and biochemical analyses show that H4-T6SS expression is activated by an H4-encoded transcriptional regulator and repressed by H-NS family proteins. Analysis of over 1,200 clinical isolates reveals that the H4-T6SS is distributed across lineages and geographic regions. Finally, we observe functional crosstalk between H4- and H2-T6SSs. Together, these findings establish H4-T6SS as a functional and repressor-gated secretion system that expands the competitive arsenal of clinical P. aeruginosa.

microbiology↗

Characterization of the Gut Microbiota and Serum Metabolomics in Patients with Type 2 Diabetes Mellitus and Newly Diagnosed Acute Coronary Syndrome

Biomarkers for the early identification of acute coronary syndrome (ACS) risk remain inadequately investigated, particularly in patients with type 2 diabetes mellitus (T2DM), for whom timely clinical intervention may substantially enhance prognostic outcomes. The gut microbiota and serum metabolites may serve as pivotal mediators in the occurrence and progression of ACS among patients with T2DM, and whether these factors can be used for the precise discrimination of patients with T2DM complicated by ACS remains to be explored. Overall, 76 participants were enrolled (38 patients diagnosed with T2DM complicated by ACS and another 38 with T2DM without ACS). 16S rRNA sequencing combined with untargeted LC-MS metabolomics revealed a dysregulated gut-serum axis in patients with T2DM complicated by ACS: enrichment of proinflammatory microorganisms (Enterococcus spp.), reduction of butyrate producers (Butyricimonas spp.) and concomitant dysregulation of circulating lipid metabolites-upregulation of PC(16:0/9:0 (CHO)) and arachidonic acid alongside downregulation of cholesterol sulfate. By integrating multiomics data and applying various feature selection methods, we subsequently identified six key biomarkers. The final constructed combined model robustly distinguished patients with T2DM complicated by ACS from those with T2DM alone (AUC = 0.983), outperforming the other single omics models. Our study revealed that the gut microbiota and related serum metabolites serve as key mediators in the onset and progression of ACS among patients with T2DM, and demonstrated their potential value as noninvasive biomarkers for the early diagnosis of T2DM complicated by ACS. Clinical PerspectiveO_ST_ABSWhat Is New?C_ST_ABSWe combined 16S rRNA sequencing with untargeted LC-MS metabolomics to dissect the gut-serum axis in patients with T2DM complicated by newly diagnosed ACS. We identified distinct gut microbial and serum metabolic signatures that distinguish ACS progression within the T2DM population. A multiomics classifier integrating clinical, microbial, and metabolic variables achieved robust diagnostic performance (AUC = 0.983) and outperformed single omics models. What Are the Clinical Implications?Integrated multiomics biomarkers facilitate the early identification of ACS progression in patients with T2DM, offering novel avenues for precision prevention, dynamic clinical surveillance, and individualized therapeutic strategies. Dysregulations of the gut microbiota and serum metabolome may play an important role in the development and progression of ACS in patients with T2DM.

microbiology↗

Molecular basis of enfumafungin inhibition and resistance in Candida glabrata β-1,3-Glucan synthase FKS1

{beta}-1,3-Glucan synthase FKS1 is essential for fungal cell wall biogenesis and serves as a validated target of widely prescribed antifungal drugs. However, the molecular mechanism of pathogenic FKS1, its modes of inhibition, and the associated resistance mechanisms remain elusive, hindering the antifungal development. Here, we focus on Candida glabrata FKS1, a clinically relevant target frequently linked to antifungal resistance. We present cryo-EM structures of C. glabrata FKS1 in multiple detergent environments and in complex with the triterpenoid antifungal enfumafungin. Integrated functional studies revealed a key catalytic residue within the conserved ED motif and uncovered structural adaptations to different membrane-mimetic environments, rationalizing FKS1s sensitivity to its surrounding membrane context. Enfumafungin binds at the extracellular membrane leaflet of cgFKS1 transmembrane domain, engaging a convex surface separated from the cytosolic active site, consistent with its role as a non-competitive inhibitor. Further analyses identified key enfumafungin-binding residues from TM5-TM6 and elucidated the molecular basis of drug resistance in C. glabrata. Collectively, these findings establish a mechanistic framework for pathogenic FKS1 function and inhibition and provide a molecular basis for the rational design of next-generation antifungal therapeutics.

microbiology↗

Polyploid cardiomyocytes define disease-specific transcriptional states in the mammalian heart

The adult mammalian heart has a limited regenerative capacity. Following injury, cardiomyocytes undergo a hypertrophic response accompanied by polyploidization, which has been described as a barrier to proliferation and regeneration of the heart1,2. However, the unique molecular programs of polyploidy, or genome multiplied cardiomyocytes, and their influence on the disease-related myocardial remodelling process remains unclear. Here, we integrate single-nuclei and high-resolution spatial multi-omics across human, rat, and mouse hearts to define novel cardiac cell states and their tissue niches in ischemic and non-ischemic heart disease. Computational analysis across scales allowed us to generate detailed networks of the cardiac tissue remodelling process as well as tissue and sub-cellular environments uniquely enriched in polyploid cardiomyocytes or their diploid origins. We identify a conserved, dichotomous transcriptional program distinguishing diploid from polyploid cardiomyocytes. Polyploid cardiomyocytes demonstrated rewired metabolic and chromatin-remodeling transcriptional programs and recapitulate the gene signature of immature human fetal cardiomyocytes. Notably, we observe that polyploid cardiomyocytes--rather than the general myocyte population--are the primary sites of enrichment for major heart-failure drug targets, including the mineralocorticoid, {beta}1-adrenergic, and glucagon-like peptide-1 receptors. Based on our cross-species dataset we further identified TNIK, a Wnt-pathway regulator expressed in polyploid cardiomyocytes across species, as a potential therapeutic target and demonstrate that pharmacological TNIK inhibition improves cardiac function after myocardial infarction in rats. Together, this species-spanning, disease-resolved study redefines cardiomyocyte heterogeneity in heart disease and suggests a therapeutic path to heart failure treatment by targeting polyploid cardiomyocytes.

genomics↗

Glucose hypometabolism and hyperphosphorylated Tau synergistically drive neuronal necroptosis

The combination of brain glucose hypometabolism and hyperphosphorylated Tau (p-Tau) pathology is the strongest known clinical predictor of imminent cognitive decline, yet how these factors cooperate to drive dementia remains unknown. Here, we show that glucose hypometabolism synergizes with p-Tau to trigger neuronal loss through necroptosis. Under low-glucose conditions, accumulated p-Tau forms a molecular scaffold that directly recruits the necroptotic kinase RIPK1, while concomitant loss of the necroptosis checkpoint protein A20 removes a critical brake on this death pathway. This dual mechanism thereby precipitates neuronal necroptosis independent of classical TNF/TNFR1 signaling paradigm. Restoring A20 expression with acetyl-L-carnitine as a dietary supplement or preventing the p-Tau - RIPK1 interaction using a RIPK1 derived competitive peptide alleviates neuronal necroptosis and brain atrophy in a Tau transgenic mouse model. Collectively, our findings uncover a previously unrecognized metabolism-driven necroptotic signaling cascade initiated by a p-Tau-RIPK1 hub, providing mechanical insight into how glucose hypometabolism synergizes with p-Tau to drive neurodegeneration.

neuroscience↗

A CRISPR-Based Humanized Model Reveals Cooperative Role of STAG2 Loss in Familial GATA2-Deficient MDS Progression

Myelodysplastic syndrome (MDS) is a heterogeneous myeloid malignancy driven by hematopoietic stem cell dysfunction, leading to ineffective hematopoiesis and cytopenias. Familial GATA2 deficiency is the most common cause of Myelodysplastic syndrome in adolescents, with progression often accelerated by co-occurring mutations, notably STAG2 loss-of-function. Using CRISPR/Cas9-mediated genome engineering in primary human fetal liver-derived hematopoietic stem cells and xenotransplantation in mice, we modeled GATA2-deficient Myelodysplastic syndrome with acquired STAG2 loss to investigate disease initiation and progression. While GATA2 deficiency alone had minimal short-term impact in our model, combined GATA2 and STAG2 loss increased hematopoietic stem cell maintenance and self-renewal, induced a myeloid-lineage bias, and expanded primitive progenitors. Single-cell transcriptional profiling revealed upregulation of stemness genes and inflammatory pathways. This humanized model faithfully recapitulates high-risk GATA2-deficient Myelodysplastic syndrome, providing mechanistic insight into how cooperative mutations drive stem cell expansion, inflammatory signaling, and myeloid skewing. Visual Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=119 SRC="FIGDIR/small/702879v1_ufig1.gif" ALT="Figure 1"> View larger version (20K): org.highwire.dtl.DTLVardef@1972beforg.highwire.dtl.DTLVardef@1c57886org.highwire.dtl.DTLVardef@16bd582org.highwire.dtl.DTLVardef@8e728a_HPS_FORMAT_FIGEXP M_FIG C_FIG Key PointsO_LIHumanized model of familial GATA2-deficiency requires the loss of STAG2 for progression to an MDS disease phenotype C_LIO_LIGATA2-ko+STAG2-ko increase HSC self-renewal, induce a myeloid-lineage bias, and trigger an inflammatory transcriptional program C_LI

cancer biology↗

Early microglial priming in Alzheimer's disease revealed by ME-seq

Epigenetic modifications, particularly DNA methylation, change dynamically with aging and are implicated in Alzheimers Disease (AD), yet how methylation interfaces with transcriptional and chromatin regulation at single-cell resolution remains poorly understood. Progress has been limited by a lack of scalable technologies capable of jointly profiling these regulatory layers. Here, we present ME-seq, a highly scalable technologies capable of simultaneously profiling DNA methylation, gene expression, and chromatin accessibility, while achieving a 100-fold reduction in cost. We generated over 400,000 single-nucleus trimodal profiles from the aging and AD mouse brain across ages, producing the first such atlas of neurodegeneration. We found AD progression triggers pronounced, disease-specific shifts in cellular composition, characterized by accelerated epigenetic aging and the expansion of disease-associated microglia (DAM). Integrative analyses, including aging clocks, revealed that DNA methylation acts as an early priming layer preceding transcriptional activation with IRF1 identified as a methylation-sensitive transcription factor serving as a gatekeeper for DAM activation. Our results establish ME-seq as a transformative tool for large-scale epigenomic dissection, revealing DNA methylation as a primary coordinator of cell-state transitions in the aging brain. Graphic abstract O_FIG O_LINKSMALLFIG WIDTH=195 HEIGHT=200 SRC="FIGDIR/small/702946v1_ufig1.gif" ALT="Figure 1"> View larger version (70K): org.highwire.dtl.DTLVardef@67435dorg.highwire.dtl.DTLVardef@177c22aorg.highwire.dtl.DTLVardef@16c6fd9org.highwire.dtl.DTLVardef@231b92_HPS_FORMAT_FIGEXP M_FIG C_FIG

genomics↗

A dual neural system supporting multi-tasking cognitive flexibility

One ubiquitous feature of human intelligence is the ability to flexibly switch between multiple tasks. Abstract task representations provide a basis for task learning, switching, and generalization, yet how the brain coordinates multiple task representations to support multitasking and task-switching remains poorly understood. We recorded functional MRI activity in human participants while they concurrently held multiple task rules in working memory and prioritized different rules for stimulus processing across trials. Our results reveal two distinct coding schemes for task prioritization. First, an active coding scheme supports the spatial separation of prioritized and unprioritized task rules: prioritized rules are represented across a distributed cortical network, whereas unprioritized rules are only found in the posterior cortex. Second, besides this active scheme, subregions of the default mode network, including the medial prefrontal cortex and hippocampus, contribute to offloading task representations into an unprioritized state and subsequently maintain sustained representations of these rules across trials via latent neural codes. Behavioral predictions using on-task, trial-wise and sustained, block-wise representations further support the neural dissociation. These findings unveil a dual neural system with distinct coding schemes that jointly enable cognitive flexibility for task implementation and switching.

neuroscience↗

The schizophrenia associated protein DISC1 is a multivalent tetrameric hub of conserved ancient fold

DISC1 is a pleiotropic protein with essential roles in neuronal proliferation and migration, intracellular signalling and cargo transport. It associates with a diverse array of partner molecules in these contexts. Mutations at the DISC1 locus are strongly associated with a spectrum of mental illnesses such as schizophrenia and depression. Despite its clinical relevance, the molecular architecture and function of DISC1 have remained largely elusive. We present a cryo-EM structure of the entire conserved core region of DISC1. The structure reveals an intricate homotetrameric assembly that harbours conserved bacteria-derived UVR domains. Four of these domains, one from each monomer, mediate extensive contacts forming two asymmetric dimer units. The dimers in turn interface with each other at two distinct coiled coil domains to achieve a two-fold symmetric tetramer. Mutational analysis shows that this tetrameric architecture enables DISC1 to simultaneously bind multiple copies of NDE1 client protein. Importantly, tetramerization and partner binding are structurally independent functions of DISC1. Altogether, our study provides a compelling molecular model of an ancient bacteria protein fold participating in the assembly of a multivalent mammalian scaffold hub that can coordinate multiple partner molecules.

neuroscience↗