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Biology subjects

Zhao, Z.

Publications and source records attributed to Zhao, Z..

At least 91 records · Page 5Linked to original sources

Single-Cell Atlas of Transcription and Chromatin States Reveals Regulatory Programs in the Human Brain

Directly measuring chromatin states alongside transcription is essential for understanding how cell-type-specific regulatory programs are established and maintained in the adult human brain. We present a large-scale single-cell multimodal atlas generated by jointly profiling transcriptome with active (H3K27ac) and repressive (H3K27me3) histone modifications across 18 brain regions. We profile >750,000 nuclei spanning 160 cell types and integrate these data with chromatin accessibility, DNA methylation, 3D genome architecture, and spatial transcriptome. This framework annotates >500,000 regulatory elements and resolves cell-type-specific chromatin states. We link enhancers to target genes, infer gene regulatory networks, and classify chromatin interactions, revealing neuron-enriched long-range Polycomb repression of developmental genes. Integrating these maps with GWAS data and sequence-based model prioritizes noncoding variants, effector genes, and vulnerable cell types for neuropsychiatric disorders. Finally, cross-species comparisons show conserved activation but more divergent repression. Together, this study provides a functional reference for interpreting noncoding variants, epigenetic memory, and brain organization. HIGHLIGHTSO_LIJoint single-cell profiling of transcriptomes with active or repressive histone modification in >750,000 nuclei across adult human brain. C_LIO_LIChromatin state annotation of >500,000 candidate cis-regulatory elements distinguishes active enhancers from accessible and Polycomb-repressed regions. C_LIO_LICell-type-resolved regulatory networks and sequence-based deep learning model prioritize functional neuropsychiatric risk variants. C_LIO_LISpatial epigenomic imputation reveals laminar layer-specific Polycomb repression programs. C_LIO_LIIntegration with 3D genome architecture reveals neuron-specific super long-range chromatin loops silencing early developmental genes. C_LIO_LIEvolutionary analysis uncovers conserved active regulatory grammar but divergent repressive landscape. C_LI

genomics↗

Structural mechanism of Necrocide 1 activation of human TRPM4 that triggers necrosis by sodium overload

The small molecule Necrocide 1 (NC1) constitutively activates human TRPM4, triggering Na influx and leading to necrotic cell death, a process termed Necrosis by Sodium Overload (NECSO). NC1 activation is specific to human TRPM4 and does not affect most of the other mammalian TRPM4 orthologs. Here, we elucidate the molecular mechanism underlying NC1 activation and its species-specific selectivity for human TRPM4 using a combination of single-particle cryo-EM, electrophysiology, and cell death assays. We identify the NC1-binding site and the key molecular determinants responsible for channel activation. In addition, we explain the insensitivity of mouse TRPM4 to NC1 and pinpoint specific residues that define NC1 specificity for human TRPM4. Given the upregulation of TRPM4 in various human cancers, our mechanistic insights into NC1 activation and specificity provide a framework for the potential development of cancer therapeutics targeting TRPM4-mediated necrosis.

biophysics↗

A Single-Cell and Spatial 3D Multi-omic Atlas of Developing Human Basal Ganglia and Inhibitory Neurons

The human basal ganglia (BG), subcortical nuclei fundamental to motor regulation and cognitive modulation, is constructed from neurons produced during gestation in the adjacent ganglionic eminences (GEs). GEs are transient structures in the ventral prenatal brain that also generate GABAergic inhibitory neurons which migrate to destinations in the BG, cortex and other destinations. This study aims to elucidate the epigenomic and 3D-genomic dynamics involved in the specification and maturation of GEs and GE-derived neurons, using single-nucleus methyl-3C sequencing (snm3C-seq), highly-multiplexed spatial transcriptomics, and chromatin+RNA single-molecule imaging. Our multi-modal data support a heterogeneous temporal progression across GE subregions, with the lateral GE (LGE) showing declining neurogenic activity in mid-gestation and caudal GE (CGE) exhibiting ongoing developmental progression through infancy. We identified regulatory programs that specify subtypes of BG principal cells, medium spiny neurons (MSN), via synchronized maturation of the 3D-epigenome. In infant brains, we found a transient short-range enriched (SE) chromatin conformation during the transition between oligodendrocyte progenitors (OPCs) and oligodendrocytes (ODCs), and a temporary shift toward Long-range Enriched (LE) chromatin conformation in projection neurons, extending previous works showing the differentiation of neurons and glial cells is associated with permanent SE and LE conformation, respectively. Lastly, we found that gene regulatory regions active in MSNs were enriched in loci associated with genetic risk for neuropsychiatric disease. Our study delineates the highly complex, lineage-specific 3D genomic dynamics in ventral progenitors and basal ganglia populations of the perinatal human brain. HighlightsO_LIJoint 3D genome and DNA methylome analysis of ventral brain progenitor zones C_LIO_LIHeterogeneous developmental progressions of the ganglionic eminences C_LIO_LIDistinct development dynamics and regulatory landscape of MSNs and interneurons C_LIO_LITransient remodeling of the 3D-genome in neurons and oligodendrocyte progenitors C_LI

genomics↗

Leptin Receptor+ cells create a perisinusoidal niche for thrombopoiesis in the bone marrow by synthesizing CXCL14

Leptin Receptor-expressing (LepR+) stromal cells in the bone marrow are a critical source of growth factors for the maintenance of hematopoietic stem cells (HSCs) and most restricted hematopoietic progenitors. An important unresolved question is whether they also regulate terminal differentiation in some hematopoietic cells. We found that LepR+ cells promote thrombopoiesis by synthesizing the chemokine CXCL14, which is expressed in the bone marrow by a subset of LepR+ cells. Cxcl14-expressing LepR+ cells extend fine processes that wrap around perisinusoidal megakaryocytes. Deletion of Cxcl14 from LepR+ cells did not significantly alter HSC function or most aspects of bone marrow hematopoiesis, including megakaryocyte generation; however, it significantly reduced the numbers of proplatelet-forming megakaryocytes in the bone marrow and platelets in the blood. CXCL14 promoted platelet formation by remodeling lipid metabolism in megakaryocytes, increasing fatty acid transporter expression and enabling megakaryocytes to take up more polyunsaturated fatty acids from circulation. A high fat diet rescued the formation of proplatelet-forming megakaryocytes and platelets in Lepr-cre; Cxcl14 fl/fl mice. CXCL14 protein was sufficient to promote platelet formation by megakaryocytes in vitro and in vivo. LepR+ cells thus create a perisinusoidal niche for thrombopoiesis by producing CXCL14, which regulates lipid metabolism and terminal differentiation in megakaryocytes. Key pointsO_LILeptin Receptor+ stromal cells regulate terminal differentiation in megakaryocytes in addition to maintaining stem and progenitor cells C_LIO_LICXCL14 from Leptin Receptor+ cells promotes the formation of platelets by remodeling lipid metabolism in megakaryocytes in the bone marrow C_LI

cell biology↗

Exploring Multi-Scale Local and Global Features in Whole Slide Images Using State Space Models

Whole slide image (WSI) classification is crucial in computational pathology, yet the gigapixel scale of WSIs makes it challenging to extract discriminative and compact WSI-level features for disease diagnosis. In this paper, we propose MambaWSI, a novel method that leverages the state space model (SSM) for WSI classification by exploring multi-scale local and global features. Unlike existing approaches that sequentially traverse WSI tiles and rely on vanilla SSMs for long-range dependency modeling, we exploit a traversal strategy in a higher-dimensional discrete space that preserves spatial proximity, enabling a first-local-then-global feature extraction process. Furthermore, to align with the clinical workflow of pathologists when examining WSIs at multiple scales, we propose a two-stage hierarchical fusion strategy: inter-scale feature alignment and aggregation, followed by attention-based fusion across magnifications, integrating complementary information from multiple magnifications. Experiments on two datasets demonstrate that MambaWSI outperforms state-of-the-art methods in classification performance.1

pathology↗

CuiT is a Cu importer required for metal homeostasis in Salmonella enterica

Copper (Cu) is an essential micronutrient that serves as a cofactor for redox enzymes but becomes toxic when unregulated. In bacteria, while Cu efflux systems are well characterized, mechanisms of Cu import remain poorly understood. Here, we characterize the major facilitator superfamily transporter CuiT (STM1486) as a key Cu importer in Salmonella enterica. Comparative genomics revealed that cuiT is evolutionarily conserved across Enterobacteriaceae, and structural modeling predicts a 12-transmembrane-helix architecture with conserved His, Met, and Cys residues suitable for Cu coordination. Functional analyses demonstrated that deletion of cuiT reduces intracellular Cu accumulation, slows Cu uptake kinetics, and diminishes expression of Cu-responsive genes, including copA, cueP, cueO, and golB. Conversely, overexpression of CuiT increases intracellular Cu but sensitizes cells to Cu stress, highlighting the need for tight regulation. Kinetic modeling indicates that CuiT mediates rapid Cu import, supporting larger intracellular Cu pools compared to Pseudomonas influx transporters. These findings position CuiT as a central component of the Salmonella Cu homeostasis network, linking Cu import to transcriptional regulation, redox balance, and stress adaptation. Our work provides mechanistic insights into bacterial Cu acquisition and suggests CuiT and associated pathways as potential targets for antimicrobial strategies. SignificanceCopper (Cu) is essential for bacterial redox enzymes but toxic when dysregulated. While Cu efflux pathways are well studied, mechanisms of Cu import are poorly understood. We identify CuiT, a conserved major facilitator superfamily transporter, as a key Cu importer in Salmonella enterica. CuiT controls intracellular Cu levels, influences Cu-responsive gene expression, and maintains redox balance and stress adaptation. Disruption or overexpression of CuiT perturbs Cu homeostasis, highlighting its regulatory importance. These findings reveal a critical bacterial Cu acquisition pathway and suggest CuiT and its network as potential antimicrobial targets, advancing understanding of metal homeostasis in pathogens.

microbiology↗

Molecular and Cellular Underpinnings of Spatial Heterogeneity in Fetal Cortical Folding

Cortical folding is a defining feature of human brain development, yet the molecular and cellular mechanisms that produce regionally specific cortical folding remain incompletely understood. Here we combined high-resolution in-utero T2-weighted and diffusion MRI atlases (23-38 weeks of gestational age) with prenatal transcriptomic profiles to map regional macrostructural and microstructural features of cortical folding to underlying gene expression. We found genes whose expression patterns correlated with cortical curvature were enriched for neurogenesis, progenitor proliferation and radial glia guided neuronal migration, and localized to ventricular zone/subventricular zone progenitor cell subtypes, supporting for the protomap hypothesis of areal specification. By contrast, cortical microstructural markers-associated gene sets were implicated in myelination, cell adhesion and extracellular matrix remodeling, and mapped to astrocyte and endothelial cell programs. The microstructure-related gene expression peaked in the early postnatal period and remained high throughout childhood, while the curvature-associated gene expression reduced with age. Several of these cortical folding-related genes overlapped with autism spectrum disorder risk loci (e.g., SCN2A, STXBP1, DVL3). Collectively, these cross-modal findings outline a sequential developmental architecture--early progenitor driven patterning followed by myelin and extracellular matrix consolidation. In addition, we released a high-resolution fetal labeling atlas to facilitate further imaging-genetic studies of early cortical development.

neuroscience↗

Sequential evolution of antidote and toxin links genetic incompatibility with immune responses

Toxin-antidote (TA) systems are selfish genetic elements that promote their own inheritance by selectively eliminating offspring lacking the module, thereby establishing post-zygotic genetic incompatibilities between individuals and populations. Although these systems are widespread across species, their evolutionary origins remain poorly understood. Here, we report the discovery of a novel TA gene pair in the nematode Caenorhabditis nigoni. The antidote gene, Cni-shls-2, is a species-specific F-box gene that arose through recent tandem duplications. Its absence results in embryonic lethality in both C. nigoni and its hybrids with the sister species C. briggsae. This lethality is caused by a maternally deposited toxin, Cni-hlix-1, a chimeric gene formed through the fusion of host and bacterial sequences. Phylogenetic and genomic analyses reveal a sequential evolution of the TA system, in which the antidote evolved prior to the toxin. The stepwise evolution of TA and the potential microbial origin of the toxin support the hypothesis that the antidote initially evolved in response to pathogen exposure, followed by the domestication of the toxin, thereby elucidating the origins of TA formation. These findings highlight the central role of host-pathogen conflict as a driving force in the emergence of genetic incompatibilities and the evolution of reproductive barriers.

evolutionary biology↗

TRPV4 Inhibition by a Natural Product Mediates Analgesia

The transient receptor potential vanilloid 4 (TRPV4) channel, a polymodal calcium-permeable cation channel, is activated by diverse stimuli, including hyposmolarity, moderate heat, mechanical stress, and acidic pH. TRPV4 plays a critical role in the onset and progression of pain and is implicated in multiple pathological conditions, positioning it as an attractive therapeutic target. However, the development of TRPV4-targeted therapeutics has been hindered by limited mechanistic understanding of its inhibition. Here, the natural product (R)-1-(3-ethylphenyl)ethane-1,2-diol (AH001) is identified as a potent, subtype-selective TRPV4 inhibitor. A potential gating mechanism of TRPV4 inhibition is proposed through a combination of structural analyses and site-directed mutagenesis. Electrophysiological studies and cryo-electron microscopy (cryo-EM) further reveal that AH001s glucuronide metabolite, AHP, retains robust TRPV4 inhibitory activity, providing a critical structural basis for rational optimization of AH001 as a lead compound. Notably, AH001 demonstrated significant efficacy in reducing neuronal hyperexcitability in dorsal root ganglia (DRGs) and produced pronounced analgesic effects across multiple pain models, highlighting its therapeutic potential in pain relief. This study offers critical structural and mechanistic insights into TRPV4 inhibition and lays the groundwork for the structure-based design of TRPV4-targeted therapeutics.

biochemistry↗

Microglia stabilize sleep homeostasis via adenosine A3 receptor signaling

Sleep homeostasis maintains the sleep-wake balance through sleep pressure, a process orchestrated by the accumulation of extracellular adenosine (eADO). Microglial Ca{superscript 2} activity has been implicated in sleep regulation, but the mechanism whereby microglia sense sleep pressure remains unclear. Here we show that microglia regulate sleep homeostasis through brain state-dependent Ca2+ activity driven by adenosine A3 receptor (A3R) signaling. Using miniaturized two-photon microscopy (mTPM) in freely behaving mice, we demonstrate that microglial Ca{superscript 2} activity is rapidly altered by brain-state transitions. Pharmacological experiments reveal that microglial Ca2+ dynamics are predominantly mediated by A3R in response to brain state-dependent eADO oscillations. Microglia-specific deletion of A3R attenuates these state-dependent Ca2+ dynamics, impairs microglial morphological plasticity across sleep-wake cycles, and leads to sleep fragmentation by increasing transitions between wakefulness and non-rapid eye movement (NREM) sleep. Together, these findings establish that microglia regulate sleep homeostasis by stabilizing both wakefulness and NREM sleep, a process critically dependent on eADO-A3R signaling.

neuroscience↗

Cryo-EM reveals the structural basis of subtype-specific, noncompetitive inhibition of the human P2X3 receptor

P2X receptors are ATP-gated cation channels, and the P2X3 subtype plays crucial roles in peripheral sensory neurons, including in chronic pain and chronic cough. Accordingly, P2X3 has attracted substantial interest as a therapeutic target. Gefapixant, a negative allosteric modulator (NAM) of P2X3, has been approved in some countries for the treatment of chronic cough; however, its limited selectivity for P2X3 homomers over P2X2/P2X3 heteromers is associated with taste disturbance as a prominent adverse effect. These limitations have motivated the development of next-generation NAMs with improved subtype selectivity, but their subtype-specific allosteric inhibition mechanisms are unclear. Here, we report the cryo-EM structure of the human P2X3 receptor in complex with ATP and the P2X3-selective next-generation NAM sivopixant, an investigational drug. Sivopixant binds to an allosteric site at the portal of the central pocket in the extracellular domain, and structure-based mutational analysis by electrophysiology identifies key residues required for sivopixant-dependent inhibition of human P2X3. Comparisons with P2X structures from other subtypes, together with gain-of-function mutants, define a structural basis for subtype-selective allosteric inhibition of the P2X3 receptor. Furthermore, structural comparisons with apo and ATP-bound open states of P2X3 receptors, together with molecular dynamics simulations, revealed that sivopixant expands the upper body domain to suppress the lower-body movements required for channel activation, thereby preventing channel opening even in the presence of ATP.

biophysics↗

Unraveling Candidatus Dermatophostum as a Novel Genus of Polyphosphate-Accumulating Organisms for High-Strength Wastewater Treatment

Dermatophilaceae polyphosphate-accumulating organisms (PAOs), formerly classified as Tetrasphaera PAOs, play pivotal roles in enhanced biological phosphorus removal (EBPR). However, their phylogenetic diversity, ecological preferences, and metabolic traits remain poorly characterized, and a robust marker gene for their classification is lacking. Here, we performed an extensive phylogenomic and metabolic analysis of Dermatophilaceae PAOs utilizing 46 newly recovered metagenome-assembled genomes (MAGs) from a laboratory-scale EBPR reactor treating high-strength wastewater and full-scale wastewater treatment plants. These analyses revealed a previously uncharacterized PAO genus, named Candidatus Dermatophostum, which is adapted to high-phosphorus environments. Its representative species, Ca. D. ammonifactor, was enriched in the EBPR reactor and its PAO phenotype was confirmed by polyphosphate staining and fluorescence in situ hybridization. Genomic, transcriptomic, and protein structure analyses revealed its specialized metabolic capabilities for phosphate metabolism, glycogen synthesis and dissimilatory nitrate reduction to ammonium. Moreover, Ca. Dermatophostum was found to be widely distributed across WWPTs worldwide, underscoring both its ecological importance and its potential role in mitigating nitrous oxide (N2O) emissions. Finally, we propose a ppk1-based classification framework that resolves Dermatophilaceae PAOs into six distinct clades, consistent with whole-genome phylogeny, and demonstrates that ppk1 can serve as a reliable marker gene for tracking these populations. Together, these findings expand the ecological and functional understanding of Dermatophilaceae PAOs and highlight their promise for advancing sustainable wastewater treatment and resource recovery.

microbiology↗

Dose-dependent NFI regulation of progenitor lifespan and output underlying human neocortical malformation

Nuclear Factor I (NFI) misexpressions in humans are associated with severe brain malformations, yet the underlying mechanisms remain poorly understood. Here we show that NFIs regulate the broad lineage progression and lifespan of radial glial progenitors (RGPs), and consequently neocortical development in a dose-dependent manner. Human cerebral organoids carrying patient-mimicking NFI mutations exhibit expression level-dependent bidirectional impairments in RGP temporal development, coinciding with patient phenotypes. In mouse models, selective removal of NFIs leads to a dramatic protraction of RGP lineage progression and lifespan, excessive progeny output, and neocortical overgrowth and abnormal folding, whereas overexpression of NFIs accelerates RGP lineage progression, resulting in developmental stage-dependent precocious productions of diverse neural progenies. Moreover, NFIs exhibit a positive auto-regulation and progressive increase in expression, and regulate distinct temporal-specific targets underlying RGP lineage progression. These results suggest that NFIs act as evolutionarily conserved key global temporal regulators of RGP lineage progression and neocortical development. HIGHLIGHTSO_LINFIs affect human RGP temporal development coinciding with patient phenotypes. C_LIO_LINFI removal protracts RGP lineage progression and lifespan with excessive progeny output. C_LIO_LINFI overexpression accelerates RGP lineage progression with precocious progeny output. C_LIO_LINFIs regulate distinct temporal-specific targets underlying RGP lineage progression. C_LI

neuroscience↗

Active zone remodeling by Bruchpilot couples synaptic architecture to Kv1/Shaker excitability control

Presynaptic active zones are known to undergo state-dependent remodeling across sleep, circadian, and experience-dependent conditions, yet how such structural changes influence synaptic computation and excitability has remained unclear. Here, we address this gap by examining the functional consequences of physiological upscaling of the active zone scaffold Bruchpilot (BRP), within the range previously observed during natural state-dependent plasticity. We show that moderate BRP elevation expands the number of functional release sites while surprisingly reducing vesicle release probability, thereby establishing a presynaptic operating mode with selectively enhanced transmission at intermediate firing frequencies. This remodeled mode depends on Kv1/Shaker potassium channels, which normally constrain the increased structural capacity generated by BRP; accordingly, perturbation of Shaker abolishes BRP-dependent reductions in release probability and unmasks an enlarged synaptic output capacity. To test the functional relevance of this coupling, we examined sleepless mutants, in which Kv1/Shaker channels are destabilized and presynaptic remodeling is compromised. We show that direct, physiological-level BRP upscaling selectively restores the Shaker/Hyperkinetic channel complex from near-undetectable levels toward normal abundance without inducing global proteomic changes, and correspondingly rescues excitability balance, oxidative stress resistance, lifespan, and mid-term memory. Together, these findings identify a mechanistic coupling between active zone architecture and intrinsic excitability control and demonstrate how presynaptic structural plasticity shapes frequency-dependent transmission and functional robustness under stress.

neuroscience↗

Real-time functional connectivity-based neurofeedback of the DLPFC-amygdala pathway during threat-exposure attenuates anxiety

BackgroundAdaptive regulation of negative emotion is vital for mental health and dysregulations in this domain contribute to the major mental disorders, including anxiety and depression. On the neural level, efficient emotion regulation has been linked to functional communication between the dorsolateral prefrontal cortex (DLPFC) and the amygdala. Gaining voluntary control over this pathway may present an effective strategy for potentiating emotion regulation. ObjectiveAgainst this background, we developed a novel connectivity-based real-time fMRI (rt-fMRI) neurofeedback (NF) training that enables individuals to gain volitional control over the DLPFC-amygdala pathway during exposure to threatening stimuli. MethodsThe study employed a pre-registered, randomized, sham-controlled design with the experimental group (n = 22) receiving real-time NF information on connectivity between the right DLPFC and the amygdala during threat exposure and the sham control group (n = 23) receiving connectivity NF from a circuit not related to emotion regulation. The ability to maintain regulatory control in the absence of feedback was assessed after four NF runs. Primary outcomes included functional connectivity of the target pathway, as well as anxiety scores. ResultsThe results demonstrate that successful acquisition of self-regulation of the rDLPFC-amygdala top-down regulatory circuit in the experimental NF group facilitated attenuation of anxiety. ConclusionIn summary, our findings suggest that real-time fMRI neurofeedback (rtfMRI-NF) allows to volitionally enhance rDLPFC-amygdala connectivity, and in turn reduces negative emotional states, rendering the training a promising neurotechnology intervention for mental disorders.

neuroscience↗

Efficient Generation of Humanized Cloned Cattle via Embryonic Stem Cell-Mediated Dual-Round Site-Specific Editing

Transgenic cloning allows genetic modification in cattle, yet its translational potential is constrained by low cloning efficiency and limited gene-editing capacity, due largely to the restricted proliferative ability of somatic donor cells. Pluripotent stem cells (PSCs), with their unlimited self-renewal ability, represent a promising alternative to overcome these bottlenecks. Here, we first established stable bovine epiblast stem cell lines (bEpiSCs) and achieved site-specific integration of the HCSN2-HLF-GFP cassette into the {beta}-casein locus, with high transfection (72.07%) and correct integration efficiency (80.48%). Following Cre LoxP mediated excision of the selectable marker, we obtained marker free HCSN2-HLF bEpiSCs that retained pluripotency markers, tri lineage differentiation potential, and supported target protein expression in immortalized bovine mammary epithelial cells. When used as nuclear donors, these cells produced blastocysts with quality comparable to in vitro fertilization (IVF) embryos. Notably, cloning with HCSN2-HLF bEpiSCs resulted in the birth of twelve calves, with significantly higher birth and survival rates (30.71% and 16.74%, respectively) than those obtained using fibroblasts. Both PCR-based genotyping of the edited loci and microsatellite kinship analysis confirmed that all cloned calves were genetically derived from the HCSN2-HLF bEpiSCs. Collectively, this study establishes an efficient embryonic stem cell based platform for targeted gene editing and rapid production of multigene edited cloned cattle, offering a scalable strategy with strong potential for industrial translation.

bioengineering↗

Neocortical temporal patterning by a two-layered regulatory network

In the developing neocortex, a diverse array of neurons with defined types and abundances are systematically generated by a limited population of radial glial progenitors (RGPs) as they undergo successive fate changes. The molecular regulation behind this intricate temporal patterning remains elusive. We undertook in-depth single-cell multi-omics analyses, discovering a two-layered regulatory framework at the core of this process. Central to this are global temporal regulators positioned above a temporal network, consisting of series of transcriptional factor (TF) hub groups under sequential state transitions. This temporal network operates not by restricting TF expressions to discrete temporal windows, but through coordinated transcriptional and chromatin-accessibility dynamics that modulate transient TF regulatory activity. Moreover, global temporal regulators specify the duration of each cascading stage and, consequently, the number of progenies generated at each stage. Loss of global temporal regulators protracts RGP lineage progression, whereas their increased activity accelerates it. These findings suggest a two-layer temporal regulatory system controlling RGP lineage progression and neural progeny output duality in mammalian neocortical development.

neuroscience↗

Mitochondria-derived PEP licenses glycerolipid synthesis via SLC25A35

Mitochondria provide a variety of metabolites, in addition to ATP, to meet cell-specific needs. One such metabolite is phosphoenolpyruvate (PEP), which contains a higher-energy phosphate bond than ATP and has diverse biological functions. However, how mitochondria-generated PEP is delivered to the cytosol and fulfills cell-specific requirements remains elusive. Here, we show that SLC25A35 regulates mitochondrial PEP efflux and glyceroneogenesis in lipogenic cells that utilize the pyruvate-to-PEP bypass. Reconstitution and structural studies demonstrated PEP transport by SLC25A35 in a pH gradient-dependent manner. Loss of SLC25A35 in adipocytes impaired the conversion of mitochondrial PEP into glycerol-3-phosphate, thereby reducing glycerolipid synthesis. Significantly, hepatic inhibition of SLC25A35 in obese mice alleviated steatosis and improved systemic glucose homeostasis. Together, these results suggest that mitochondria facilitate glycerolipid synthesis by providing PEP via SLC25A35, offering lipogenic mitochondria as a target to limit glycerolipid synthesis, a pivotal step in the pathogenesis of hepatic steatosis and Type 2 diabetes.

cell biology↗