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Wang, L.

Publications and source records attributed to Wang, L..

At least 37 records · Page 2Linked to original sources

SF3B1 mutation generates novel peptides from long non-coding RNAs

While mRNA alternative splicing caused by somatic mutation in SF3B1 is well-characterized, long non-coding RNAs (lncRNAs) impacted by this mutation are completely unknown. Here, we report long-read sequencing of full-length transcripts from cell lines with and without SF3B1 mutation. We present ALLR (Annotation of human lncRNAs using Long-Read sequencing), a computational workflow to identify and quantify lncRNAs, and to annotate their potential roles in impacting cellular functions. Harnessing matched short-read RNA sequencing and proteomic data, we demonstrate that SF3B1 mutation generates thousands of novel lncRNAs with diverse levels of alternative splicing. Moreover, SF3B1 mutation-associated lncRNAs produce translatable peptides with putative functions, immunogenicity, and potential to bind proteins with impact on cellular signalling networks. 47 lncRNAs could also be detected in primary chronic lymphocytic leukemia (CLL) samples and are associated with significant risks towards adverse disease prognosis, in conjunction with other known CLL risk factors. Our work demonstrates the utility of long-read sequencing for lncRNA research and provides a new territory of functional RNA molecules that SF3B1 mutation may use to impact cancer.

genomics↗

Structural Basis of γδ T-Cell Receptor Crosslinking and Activation by a Spontaneously Dimerized Fab

The gamma delta T-cell receptor ({gamma}{delta} TCR) mediates {gamma}{delta} T-cell responses that are crucial for immune defense, tissue surveillance, and homeostasis. While recent studies suggest that {gamma}{delta} TCRs engage ligands multivalently, how multivalent engagement activates the {gamma}{delta} TCR remains elusive. Here, we present the structures of the V{gamma}9V{delta}2 (clone G115) TCR in both the inactive and the agonist-crosslinked active states. In the {gamma}{delta} TCR lipoprotein complex, cholesterol and phospholipids form a "barrier" that isolates CD3{zeta}{zeta} from the other subunits and likely prevents autoactivation. As an agonist, the Fab fragment of the UCHT1 antibody dimerizes upon binding the V{gamma}9V{delta}2 TCR, thereby crosslinking and activating the receptor. Cryo-EM analysis of Fab-crosslinked V{gamma}9V{delta}2 TCR identifies three Fab dimer interfaces, one between the two light chains and the other two between light and heavy chains. These Fab-Fab interfaces, together with the Fab-CD3{epsilon} interface, mediate the assembly of the V{gamma}9V{delta}2 TCR and UCHT1 Fab into 2:2 tetramers. Upon activation, the V{gamma}9V{delta}2 TCR becomes conformationally plastic and loses enriched lipids, including cholesterol and phosphatidylethanolamine. Our findings reveal a dimerization-driven activation mechanism, inform the design of rigid TCR-crosslinking agonists, and suggest multivalency-induced clustering as a general paradigm for {gamma}{delta} TCR activation.

immunology↗

A telomere-to-telomere genome of Holstein cattle resolves chromosome-end architecture and the genetic basis of telomere length

Telomeres safeguard chromosome-end integrity, yet population-scale dissection of telomere-length genetics has been largely restricted to humans. Here, we report a 3.01-Gb telomere-to-telomere (T2T) genome of Holstein cattle that resolves repeat-rich chromosome ends and centromeres and enables telomere-length quantification at single-chromosome-end resolution. Holstein chromosome ends show marked telomere-length asymmetry and end-specific variation in telomere variant repeats, subtelomeric tandem repeats, GC/CpG composition, and DNA methylation. Using sequencing-depth-corrected telomere-length phenotypes from 9,591 cows, teloGWAS identifies major loci encompassing RTEL1, CTC1, and TERT, while multi-tissue eQTL, sQTL, TWAS, and co-expression analyses prioritize CTC1 and implicate DNA replication, DNA repair, and stress-response networks. Together, these findings extend population-scale telomere genetics beyond humans and establish a sequence-resolved framework for chromosome-end biology and telomere-informed livestock genomics.

genomics↗

The Arabidopsis outward K+ channel GORK mediates flg22-induced K+ efflux and stomatal closure

Transient K+ efflux occurs rapidly following pathogen-associated molecular pattern (PAMP) perception by pattern recognition receptors (PRRs) as part of pattern-triggered immunity (PTI). However, the molecular identities of the K+ channels responsible for PTI-associated K+ efflux and the mechanisms linking immune signaling to K+ channel regulation remain largely unknown. Here, we show that the channel GUARD CELL OUTWARD RECTIFYING K+ (GORK) is required for K+ efflux and stomatal closure induced by flg22, a model PAMP derived from bacterial flagellin. BOTRYTIS-INDUCED KINASE 1 (BIK1), a receptor-like cytoplasmic kinase associated with immune receptor complexes that functions as a central regulator of PTI, interacts with GORK and phosphorylates the channel on the conserved T199 residue in vitro. Electrophysiological analyses indicate that BIK1 inhibits GORK activity in a kinase-dependent manner and that T199 plays an essential role for GORK function. Together, this study identifies GORK as the key K+ channel executing rapid PTI-associated K+ efflux and associated stomatal closure, thus shedding light on the mechanisms of early immune signaling.

plant biology↗

Intracellular complement Factor B couples inflammatory sensing to metabolism, chromatin regulation and maladaptive tissue repair

Inflammatory signals are broadly conserved, yet how tissue context converts them into programs of recovery or maladaptive repair remains unclear. Using kidney injury as a model of inflammation-to-repair transitions, we identify an injury-induced proximal-tubule complement program in which cell-intrinsic complement proteins are repurposed across subcellular compartments to couple inflammation to metabolic and chromatin regulation and promote maladaptive fibrotic remodeling. Mechanistically, myeloid-derived IL-1b; signals through IL-1R1 on injured tubular cells to recruit NF-kB and AP-1 to C3 and Cfb, coordinately inducing complement component 3 (C3) and Factor B (FB). Cytoplasmic FB drives cleavage-activation of cell-intrinsic C3, which supports tubular cell mitochondrial metabolic adaptation to stress and accumulation of C3aR-expressing macrophages around injured tubules. Nuclear FB, on the other hand, binds chromatin through a previously unrecognized DNA-binding interface and mediates histone H3 proteolysis and the preferential remodeling of chromatin promotors enriched in transcriptional programs relevant to maladaptive repair. Key features of this injury-associated C3-FB response, including intranuclear FB, are conserved in human kidney disease, associate with kidney dysfunction, and distinguish diseased from healthy kidneys. Together, these findings suggest that extracellular complement-targeting therapies may miss disease-relevant intracellular functions and suggest nuclear FB as a distinct target whose chromatin interaction and processing capacity could selectively limit maladaptive tissue responses beyond conventional inhibition.

immunology↗

Niche-dependent epistasis within the cancer genome shapes metastatic fitness

Epistasis, the genetic interaction between loci, directs non-additive genotype-to-phenotype outcomes. Within a multicellular organism, how the tissue niche (E) shapes gene-by-gene epistasis (GxG) and its phenotypic consequences remains poorly studied. Using tumor lung metastasis as an experimental model, we mapped GxGxE through combinatorial CRISPR perturbation coupled with depletion of defined host myeloid populations in mice. The metastatic niche first selects disseminated tumor cells on GxG epistatic fitness, then drives transcriptome convergence regardless of genotype. Removing anatomically distinct myeloid populations reshaped the metastatic epistasis landscape despite identical tumor genotypes. Gene-by-gene-by-environment epistasis therefore operates at the organismal level, with interaction magnitude and sign set by niche cells. Beyond metastasis, our data suggest that the tissue niche conditions how genetic interactions translate into divergent phenotypes.

genetics↗

Asymmetric assembly underlies activation mechanism of neuronal GIRK1/2 channels

G protein-gated inwardly rectifying potassium (GIRK; Kir3) channels are principal effectors of inhibitory GPCR signaling. Here we combine cryo-electron microscopy, single-molecule imaging, electrophysiology and molecular dynamics to define the architecture and activation of neuronal GIRK1/2 channels. GIRK1/2 preferentially assembles as an asymmetric heterotetramer containing one GIRK1 and three GIRK2 subunits. Three PIP2; molecules bound to GIRK2 promote partial cytoplasmic-domain docking, whereas engagement of a fourth PIP2 by GIRK1 completes docking and opens the helix bundle crossing gate. GIRK1 also remodels the electrostatic environment beneath the selectivity filter, where its E141 and D173 residues create a permeation module that enhances K+ conduction. The GIRK1-selective activator ML297 binds at the GIRK1-GIRK2 interface and controls both permeation and gating. These findings establish how asymmetric assembly couples sequential lipid-dependent gating to efficient K+ permeation and GIRK1-dependent pharmacological activation.

biophysics↗

Stoichiometry-dependent gating and structural pharmacology of cardiac GIRK1/4 channels

Cardiac G protein-gated inwardly rectifying potassium-K+ (GIRK) channels, formed by GIRK1/4 heterotetramers or GIRK4 homotetramers, are crucial regulators of heart rate, and their dysfunction is associated with atrial fibrillation. Despite their therapeutic potential as anti-arrhythmic targets, development of selective GIRK modulators has been limited by an incomplete understanding of their structures, gating mechanisms, and pharmacology. Here, we report high-resolution structures of the GIRK4 homotetramer and of GIRK1/4 heterotetramers, revealing that they form in unexpected 1:3 and 2:2 assembly stoichiometries that we corroborate using cell-based single molecule microscopy. Electrophysiological assays and molecular dynamics simulations further show that incorporation of one or two GIRK1 subunits into GIRK4-containing channels progressively opens the helix bundle crossing (HBC) gate and increases basal channel activity. Additional structures of GIRK1/4 complexes with ML297, a small-molecule ligand selective for GIRK1-containing channels, reveal distinct GIRK1-centered intersubunit binding environments. Remarkably, ML297 inhibits GIRK1/4 channels with a 1:3 stoichiometry but potentiates channels with a 2:2 stoichiometry, establishing a direct link between subunit composition, ligand-binding environment, and pharmacological efficacy. Together, these findings provide a structural and mechanistic framework for the rational design of ligands with enhanced selectivity among cardiac and neuronal GIRK channel heterotetramers.

molecular biology↗

Tubule extension by plastids is due to increase in bilayer-forming galactolipids at the outer envelope membrane

Sporadically, all plastids produce dynamic tubular extensions in response to myriad stresses. Although the use of fluorescent proteins revealed these transient tubules to be stroma-filled and led to their being called stromules, the mechanism underlying tubule extension from a spheroidal plastid remained unknown. As plastids in viridiplantae have two bounding membranes the fluid stroma remains confined within the inner envelope membrane (IEM) while the outer envelope membrane (OEM) around the IEM forms the interface with the rest of the cytoplasm. Here, using a sucrose treatment for inducing tubules in the dark in transgenic Arabidopsis plants expressing different stroma and OEM-targeted fluorescent proteins we carried out comparative molecular-genetic and lipidomics analyses. Our data strongly suggest that plastid tubule formation occurs due to increase in bilayer-forming galactolipids such as digalactosyldiacylglycerol (DGDG) on the OEM. While the dynamic behaviour of stromules occurs within an external encasing OEM, stresses such as phosphate starvation and high light intensity cause the galactolipid-rich OEM-tubule projecting beyond the stromule to be shed into the cytoplasm. OEM shedding from long tubules with extended plastid outreach into the cell suggests their important role in dispersing plastid-derived, membrane-stabilizing, galactolipids to the rest of the cell to augment its resilience to stress.

plant biology↗

Oncogenic ESR1 fusions form chromatin-anchored condensates that remodel nuclear architecture

Estrogen receptor (ESR1) fusions are recurrent drivers of endocrine-resistant breast cancer, yet their mechanisms of action remain poorly understood. Here, we show that ESR1-e6 fusion proteins, including ESR1-DAB2, ESR1-SOX9, and ESR1-YAP1, assemble into nuclear condensates across multiple cell types. Sequence analysis reveals that these fusions combine chromatin-targeting domains with increased intrinsic disorder, promoting multivalent interactions and phase separation. Live-cell imaging, fluorescence recovery after photobleaching, and mechanical perturbation demonstrate that condensates exhibit liquid-like properties, but progressively mature into stable, viscoelastic assemblies constrained by chromatin. Disruption of DNA binding abolishes condensate formation, indicating that chromatin engagement is essential for their assembly and organisation. ESR1 fusion condensates localise to chromatin-depleted regions, reduce nuclear stiffness, and promote chromatin decompaction, consistent with active remodelling of nuclear architecture. We propose that ESR1 fusions exploit phase separation to generate chromatin-anchored assemblies that reorganise the nuclear microenvironment, providing a physical framework through which ESR1 fusions may support sustained transcriptional activity, endocrine resistance and tumour progression.

cell biology↗

Genetic risk and inflammatory signaling converge on cell type-specific regulatory programs in type 1 diabetes

Type 1 diabetes (T1D) is a complex autoimmune disease characterized by the destruction of insulin-producing pancreatic {beta} cells. Both genetic susceptibility and epigenetic dysregulation contribute to T1D risk. Recent studies have reported {beta}-cell dysfunction before disease onset, suggesting that {beta}-cell-intrinsic mechanisms contribute to pathogenesis. However, the mechanistic link between disease-associated variants and {beta}-cell dysfunction remains poorly understood. We hypothesized that a subset of T1D-associated variants directly influences cell type-specific candidate cis-regulatory elements (cCREs) by disrupting transcription factor (TF) binding and altering gene expression. To define cell type-specific cCREs in human islets, we integrated publicly available epigenomic datasets, including bulk histone modification profiles and single-cell multiomic data from human pancreatic islets. We combined these data with T1D genome-wide association study (GWAS) variants to identify disease-associated SNPs located within enhancer regions. Using multiomic datasets from PANC-DB, we characterized cell type-specific chromatin accessibility in nondiabetic and T1D islets and identified regulatory regions that may control gene expression in {beta} cells and other islet cell types. We then applied ChromBPNet, a deep learning model that predicts base-pair-resolution chromatin accessibility from scATAC-seq data, to evaluate how specific variants may alter local regulatory activity. In parallel, we used TF footprinting to nominate TFs likely to bind these variant-containing regions. These analyses identified several T1D-associated SNPs predicted to alter chromatin accessibility at candidate TF binding sites, suggesting mechanisms by which noncoding variants may contribute to {beta}-cell dysfunction and T1D susceptibility. Our findings link T1D-associated variants to cell type-specific enhancer activity and regulatory pathways and provide candidates for future mechanistic studies.

genomics↗

Early dynamics of a neutrophil interferon program drive immunotherapy resistance and limit durable anti-tumor immunity

Despite the remarkable success of immune checkpoint blockade (ICB), durable clinical benefit remains limited to a subset of patients, highlighting the need for predictive biomarkers and new therapeutic targets. Here, we investigated the early immune dynamics associated with anti-PD1 responsiveness using longitudinal single-cell transcriptomics, spatial transcriptomics, and neutrophil-specific genetic perturbations in preclinical models of triple-negative breast cancer. We identified a conserved neutrophil interferon-stimulated gene (ISG) program that emerges before overt tumor divergence and predicts resistance to anti-PD1 therapy. Successful treatment was associated with an early reduction of IFN-responsive neutrophils in both blood and tumor tissues, whereas persistent neutrophil IFN signaling correlated with therapeutic resistance. Mechanistically, genetic disruption of either type I or type II interferon signaling in neutrophils enhanced anti-PD1 efficacy and promoted durable anti-tumor immune memory. Spatial analyses further revealed an inverse association between IFN-responsive neutrophils and tertiary lymphoid structure-enriched regions during effective therapy. Together, these findings identify IFN-responsive neutrophils as early determinants of immunotherapy outcome and establish dynamic neutrophil interferon programs as candidate blood-based biomarkers and therapeutic targets for cancer immunotherapy.

cancer biology↗

Deciphering the gene-centric spatial dynamics across tissue and time with GeneSPOT

Spatial omics technologies provide unprecedented opportunities to investigate how molecular programs are organized within tissues. However, existing analytical frameworks primarily focus on identifying cellular states and characterizing differentially expressed molecular features across these states. The relational spatial organization of molecular features and its dynamics across biological contexts therefore remain largely unexplored. Here, we present GeneSPOT, a gene-centric computational framework for characterizing the spatial relationships among genes and quantifying their reorganization across biological conditions. Although gene-centric in design, GeneSPOT generalizes to other molecular features. Across diverse applications, GeneSPOT resolved tissue structures, integrated paired and unpaired spatial multi-omics data, unveiled the spatial convergence of gene programs during embryonic development, and identified aging-associated spatial reorganization among genes whose expression did not change significantly with age. GeneSPOT thus complements conventional cell-centric analysis, providing a framework for deciphering how spatial relationships among molecular features are reorganized across biological conditions and over time.

bioinformatics↗

CTR1-mediated copper uptake orchestrates metabolic-epigenetic regulation of pathogenic TH17 cells in autoimmune disease

Pathogenic T helper 17 (pTH17) cells are a subset of CD4+ T cells driving autoimmune diseases including multiple sclerosis (MS). Compared to homeostatic TH17 cells and other TH subsets, pTH17 have enhanced mitochondrial function and oxidative phosphorylation (OXPHOS) that supports their differentiation and pathogenic function. Here we identify Copper Transporter 1 (CTR1), encoded by Slc31a1, as essential for copper uptake in CD4+ T cells, OXPHOS and pTH17 cell differentiation and function. While copper levels are known to be higher in the cerebrospinal fluid of patients with MS compared to healthy individuals, and excess copper contributes to oligodendrocyte loss in murine models of MS, the effect of copper on T cell function and pathogenicity in MS are unclear. We demonstrate that deletion of Slc31a1 in CD4+ T cells decreased intracellular copper levels, disrupting mitochondrial respiration and rewiring metabolism. These changes altered the epigenetic landscape of pTH17 cells by impairing DNA demethylation capacity, leading to hypermethylated DNA and altered chromatin accessibility at key binding sites for AP-1 transcription factors essential for pTH17 differentiation. As a result, CTR1-deficient T cells showed defective differentiation into pTH17 cells, with decreased production of IL-17A and expression of TH17 signature genes, while the differentiation of other CD4+ T cell subsets remained largely unaffected. Moreover, T cell-specific deletion of Slc31a1 protected mice from central nervous system (CNS) inflammation in the experimental autoimmune encephalomyelitis (EAE) model of MS by suppressing clonal expansion of autoreactive CD4+ T cells. These findings establish copper as a critical regulator of pTH17 differentiation and function, revealing a previously unknown molecular link between copper homeostasis, metabolism and epigenetic regulation governing pTH17-mediated autoimmunity.

immunology↗

RNASeek: A Cross-Phyla Generative Foundation Model for Multipurpose RNA Modeling and Reinforcement Learning-Based Design

RNA plays central roles in regulating information flow and provides a versatile substrate for engineering biological functions. While large language models (LLMs) have transformed natural language processing and protein design, a general framework connecting RNA foundation models to functional sequence design remains limited. Here, we present RNASeek, a 1.6-billion-parameter generative foundation model built on a DeepSeek architecture and trained on a cross-phyla transcriptomic corpus for RNA sequence representation and generation. Natural-language tokens enable flexible conditional prediction and sequence design using a unified backbone. RNASeek captures species-specific transcript features and intron-exon boundaries in a zero-shot setting. We then fine-tune RNASeek to predict ribozyme self-cleavage activity and viral mRNA stability, revealing interpretable sequence features associated with function, including ribozyme loop flexibility and stem stability, as well as AU-rich motifs associated with mRNA stability. We use these functional predictors as reward models and apply Group Relative Policy Optimization (GRPO) to update the generation policy of RNASeek toward sequences with desired properties. GRPO-guided generation produces faster-cleaving ribozymes and stability-enhancing 3' UTRs while satisfying user-specified IUPAC constraints. Experimentally validated RNASeek-generated ribozymes achieve wild-type levels of activity, while RNASeek-generated 3' UTR sequences exceed the performance of the training data and benchmarked AI-generated 3' UTRs. Together, RNASeek establishes a unified pretrain-predict-optimize framework that connects learned RNA function to controllable de novo sequence design and provides a general strategy for engineering regulatory RNAs with desired properties.

bioengineering↗

Loss of DNA Demethylase Enhances Arsenic Resistance Via Reducing of PIN2 Antisense Long Noncoding RNA

DNA methylation dynamics regulate diverse plant stress responses, but the mechanisms governing arsenic (As) tolerance through epigenetic pathways remain largely unknown. Here we report that Arabidopsis mutants lacking the DNA demethylase, REPRESSOR OF SILENCING (ROS1), show substantially enhanced As resistance. Integrating transcriptome and methylome data, we found that PIN-FORMED 2 (PIN2), encoding an auxin efflux carrier that also transports As out of cells, represents a key ROS1 target. In ros1, we observed increased methylation in the last exon of PIN2, a region functioning as the promoter for an antisense long non-coding RNA (lncRNA). Hypermethylation of the promoter suppresses the antisense lncRNA, which follows reduction of sense PIN2 transcription. As a result, PIN2 expression increases in ros1 mutants during As exposure, enhancing As tolerance. Analysis of ros1 pin2 double mutants confirmed that PIN2 acts downstream of ROS1 in As tolerance. Our study demonstrates an epigenetic pathway in which ROS1 regulates As tolerance by controlling PIN2 expression through antisense lncRNA-mediated transcriptional interference, offering new epigenetic strategies using plants in heavy metal contaminated environments.

plant biology↗

UniWave-2: A Hybrid Model for Nucleic Acid Waveform Feature Extraction Enhanced by Fourier and Wavelet Transforms

Motivation: Traditional methods primarily rely on statistical features such as k-mers and GC content, making it difficult to capture complex internal relationships within sequences. Deep learning models typically rely on discrete encodings, leading to issues such as information sparsity, dimensional redun-dancy, and disruption of sequence continuity. Our previous UniWave-1 framework transforms se-quences into waveform signals; however, it lacks comprehensive physicochemical integration and com-putational efficiency. Results: We propose the UniWave-2 feature extraction framework. UniWave-2 incorporates three key advancements: (i) integration of hydrophobicity into the encoding scheme; (ii) enhancement of wave-form resolution through Fourier transform, coupled with wavelet transform to precisely capture both local details and global periodic patterns; and (iii) development of a lightweight multi-scale GRU model that facilitates cross-dimensional feature interactions, captures bidirectional temporal dependencies, and integrates long- and short-range patterns with spatial positional awareness, thereby yielding rich feature representations. UniWave-2 achieved competitive performance across multiple genomic tasks, while ISM analysis demonstrated that waveform encoding enables interpretable attribution without re-lying on gradient information. These results establish UniWave-2 as a lightweight and interpretable framework for nucleic acid sequence analysis.

bioinformatics↗

Postnatal sensorimotor experience causally shapes hemispheric specialization across motor and language networks

The functional organization of the human brain is shaped by the interplay between innate constraints and postnatal experience. Hemispheric specialization, as a fundamental organizing principle of brain function, raises unresolved questions about how postnatal experience shapes lateralization and importantly, whether different lateralized cognitive systems develop through shared or independent mechanisms. We leveraged a natural experiment in individuals with obstetric brachial plexus injury (OBPI) in the right upper limb, resulting in lifelong left-hand dominance dissociated from the typical predisposition, to address these questions. Using functional MRI experiments during manual motor tasks, we found that altered hand-use experience selectively reshaped hemispheric organization in higher-order frontoparietal motor regions. Specifically, individuals with right OBPI showed reduced left-hemisphere dominance and rightward reorganization of abstract, hand-independent action representations relative to controls and individuals with left-side OBPI, whereas primary sensorimotor and subcortical regions preserved their canonical lateralizedl organization. Strikingly, experience-dependent motor reorganization extended beyond the motor system:individuals with right OBPI exhibited reduced left lateralization of the language network in Broca's area (BA44) during sentence listening. Crucially, language lateralization in BA44 covaried with the left lateralization of frontal motor areas, particularly for the compensatory, functional left hand. These findings demonstrate that postnatal bodily experience shapes the developmental emergence of hemispheric specialization, specifically in higher-order motor and language networks, and revealed coordinated organization between action and language systems.

neuroscience↗