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Biology subjects

Wu, Q.

Publications and source records attributed to Wu, Q..

At least 37 records · Page 2Linked to original sources

FXR-mediated recruitment of PPP1CB suppresses SMAD2/3 phosphorylation to mitigate pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal interstitial lung disease with limited treatment options and poorly understood molecular underpinnings. Dysregulated TGF-{beta}/SMAD signaling is a key driver of fibrotic remodeling, promoting persistent myofibroblast activation and excessive extracellular matrix deposition. Here we identify the Farnesoid X receptor (FXR), a bile acid activated nuclear receptor, as a previously unrecognized suppressor of pulmonary fibrosis. FXR expression is significantly reduced in lung tissues from patients with PF and in myofibroblasts derived from BLM-induced mouse models, correlating inversely with fibrosis severity. Genetic ablation of FXR exacerbates BLM-induced pulmonary fibrosis by promoting fibroblast hyperactivation and dysregulation of the TGF-{beta}/SMAD signaling pathway. Mechanistically, we identify PPP1CB as a previously unrecognized FXR-interacting protein in primary myofibroblasts derived from IPF patients. We further show that FXR both increases chromatin accessibility at the PPP1CB locus and assembles a functional complex with PPP1CB, which in turn promotes SMAD2/3 dephosphorylation and suppresses their nuclear translocation. Notably, the clinical-stage FXR agonist TERN101 exhibits potent therapeutic efficacy in a BLM-induced mouse pulmonary fibrosis model. These findings establish FXR as a critical antifibrotic regulator in lung tissue and suggest that pharmacological activation of FXR may offer a promising therapeutic strategy for IPF.

cell biology↗

Primitive GLMY Homology: An Algebraic Topology Approach for the Quantitative Characterization of Graph Pangenomes toward Population Genetic Analysis

A central task in population genetics is to identify genetic diversity in a population containing a number of individuals. In recent years, with the development of the third generation sequencing (TGS) technology, pan-genome research has become a hot topic. Although graphical representation has been a popular way to represent the pangenome, few works have attempted to describe it in a more mathematical way. In this paper, we used 79 high-quality assembly data of third-generation sequencing in yeast (includingSaccharomyces cerevisiae and Saccharomyces paradoxus) to construct the graph pangenome, and introduced the Primitive GLMY (Grigoryan-Lin-Muranov-Yau) Homology in algebraic topology to quantitatively represent the pan-genome. We further made an intriguing attempt to conduct a population genetic analysis of this resulting dataset from the topological features of the graph pangenome. We found that there was good agreement between the obtained results and the biological context. We believe this study has developed a method for population genetic analysis of the genetic diversity of genome structural variation.

genetics↗

Using Natural Vector Method for Population Genomic Analysis on Human Mitochondrial Genome Data

The natural vector method is an important method for the analysis of biological sequences. In this study, we applied this method to population genetic analysis, with the core purpose of using it to evaluate the characteristics of a set of sequences rather than just pairwise comparison. We used the mitochondrial genome dataset from the human 1000 Genomes Project as a dataset to verify the feasibility of this improved natural vector method. The results showed that the modified natural vector method could be used for various population genetic approaches at least in the sense of population average, including the calculation of principal component analysis, population structure analysis and genetic diversity parameters. The results were in good agreement with those based on traditional molecular genetic markers such as SNP. The new method validates the feasibility of natural vector method for population genetic analysis and provides a framework for the application of matchless pair method to population genomic analysis on a wider scale.

genetics↗

A novel AR molecular glue degrader via bivalent engagement of the N-terminal domain and RNF213-UBE2J2 complex

Targeted protein degradation enables the elimination of disease-relevant proteins through induced proximity between E3 ligases and substrates. Current androgen receptor (AR) therapies act via the ligand-binding domain (LBD) but fail against constitutively active LBD mutants or splice variants such as AR-V7. Here, we identify GZL626, a small-molecule degrader that induces proteasome-dependent degradation of both full-length AR and AR-V7. GZL626 suppresses AR transcriptional activity, inhibits proliferation of AR-positive prostate cancer cells, and blocks SARS-CoV-2 infection. Mechanistically, GZL626 binds the intrinsically disordered AR N-terminal domain (NTD) and promotes formation of a noncanonical RNF213-UBE2J2-AR ternary complex that drives AR ubiquitination and degradation. The AR DNA-binding domain (DBD) acts as a structural hub within this assembly. Distinct from PROTACs or classical molecular glues, GZL626 engages both AR and RNF213 bivalently, remodeling protein interactions to stabilize a functional E3-E2-substrate complex. These findings establish GZL626 as a first-in-class NTD degrader with potential to overcome resistance in advanced prostate cancer.

biophysics↗

PFOS aggravates atherosclerosis via Bacteroides caecimuris expansion-driven bile acid remodeling and subsequent intestinal FXR-TLR3 signaling cascade

BACKGROUNDPerfluorooctane sulfonate (PFOS) is a widely distributed persistent organic pollutant in the environment and has been associated with an increased risk of atherosclerosis. However, the underlying pathogenic mechanisms remain largely unclear. This study aimed to investigate the effects of PFOS on atherosclerosis and its associated gut-vascular axis. METHODSPseudo-germ-free mouse models and fecal microbiota transplantation (FMT) were used to determine the role of the gut microbiota in PFOS-induced atherosclerosis. Metagenomic sequencing was performed to characterize alterations in gut microbial composition following PFOS exposure, and targeted metabolomics was used to assess bile acid profiles in the ileum and plasma. Transcriptomic analysis of Bacteroides caecimuris (B.caecimuris) was conducted to explore the reasons for the increased abundance of B.caecimuris after PFOS exposure. In addition, intestinal transcriptomics and ChIP-qPCR were performed to validate transcriptional regulation within the FXR-TLR3 signaling axis. RESULTSAmong 127 participants with paired serum and fecal samples, including 82 patients undergoing coronary angiography with Gensini scores (GS score), fecal PFOS levels were significantly associated with lipid profiles and GS score, whereas serum PFOS showed no such association.Mechanistically, PFOS exposure promotes intestinal enrichment of B.caecimuris by upregulating its tolC gene, thereby enhancing efflux capacity.This microbial shift was accompanied by reduced levels of tauro-ursodeoxycholic acid (TUDCA) and aberrant activation of intestinal FXR signaling.Further analyses demonstrated that FXR activation upregulated TLR3 expression and promoted inflammatory responses and atherosclerosis progression via the TLR3-NF-{kappa}B signaling axis. Both intestinal epithelial-specific FXR deficiency (Fxr{Delta}IE) and TUDCA supplementation significantly suppressed pathway activation and alleviated disease phenotypes.Functional experiments identified TLR3 as a key downstream effector of FXR. Overexpression of TLR3 abolished the protective effects observed in Fxr{Delta}IE mice. Moreover, pharmacological inhibition of TLR3 using CU CPT-4a significantly improved established atherosclerotic lesions in vivo. CONCLUSIONSThis study identifies a gut microbiota-driven FXR-TLR3 signaling axis that mediates PFOS-induced atherosclerosis. These findings provide new mechanistic insights into environmentally induced cardiovascular disease and suggest potential targets for risk assessment and therapeutic intervention.

pathology↗

SELECT-seq allows Pre-Sequencing Enrichment of SNP Edits in One-Pot Single-Cell Whole-Transcriptome Sequencing

Advances in high-throughput sequencing have associated millions of putative genetic variants with disease. However, scalable experimental methods to establish causal relationships between genetic variants and downstream transcriptional outcomes remain a major challenge. Single-cell methods that integrate genotyping with transcriptomic profiling provide a way to address this, but do not enable pre-sequencing enrichment of correctly edited cells, limiting scale. We present SELECT-seq (SNP Enrichment Leveraging Cas12a Targeting), a rapid method that allows SNP-specific PCR amplification and Cas12a-mediated fluorescence detection simultaneously with whole-transcriptome amplification. This one-pot workflow enables identification and enrichment of SNP-bearing single cells, making a rapid and scalable methodology for analysis of genotype-phenotype linkage avoiding laborious single cell cloning steps. As a proof of principle we show that SELECT-seq distinguishes U-2 OS and T-47D cell lines based on a PIK3CA (NM_006218.4:c.3463A>G) mutation while preserving transcriptome integrity. It physically enriches a rare NRF2 T80K (NM_006164.5:c.390C>A) mutant cells (6.7%) from a prime-edited pool, achieving 86% genotype accuracy, and shows 87.5% directional concordance in the transcriptomic effects compared with a clonal NRF2 T80K cell line. SELECT-seq thus provides a rapid, scalable and widely accessible approach for mapping genotype-phenotype relationships at single-cell resolution.

molecular biology↗

Endothelial Baf60c in BPD-Associated Pulmonary Hypertension

BACKGROUNDBronchopulmonary dysplasia-associated pulmonary hypertension (BPD-PH) complicates prematurity and carries substantial morbidity in extremely preterm infants. Pulmonary microvascular endothelial cell (PMVEC) dysfunction promotes capillary rarefaction and vascular remodeling, but epigenetic mechanisms after neonatal hyperoxia are poorly defined. Baf60c (SMARCD3), a SWI/SNF subunit supporting vascular homeostasis, and Smarcc2 (BAF170), a PBAF scaffold subunit linked to proliferative signaling, have not been studied together in BPD-PH. METHODSNeonatal C57BL/6 mice were exposed to 85% oxygen for 14 days. Right ventricular systolic pressure (RVSP), right ventricular hypertrophy, lung weight index, and pulmonary histopathology were assessed; PMVEC proliferation, migration, and invasion were measured. Transcriptome sequencing with GO/KEGG analyses, siRNA knockdown, LY294002 inhibition, coimmunoprecipitation, and Western blotting mapped the Baf60c-Smarcc2-PI3K-Akt-mTOR axis. A Tie1-driven, lung-tropic adeno-associated virus delivered by superficial facial vein injection at postnatal day 1 enabled PMVEC-specific Baf60c overexpression. RESULTSHyperoxia increased RVSP, right ventricular hypertrophy, and lung weight index, impaired alveolarization, reduced capillary density, and promoted arteriolar remodeling. PMVEC function was impaired, with PI3K-Akt pathway enrichment and suppressed signaling. Hyperoxia decreased Baf60c and increased Smarcc2. Baf60c knockdown upregulated Smarcc2, suppressed PI3K-Akt-mTOR, and phenocopied hyperoxia; Smarcc2 knockdown had opposite effects. Baf60c bound Smarcc2 but not PI3K. PMVEC-specific Baf60c overexpression attenuated pulmonary hypertension and right ventricular hypertrophy and partially improved alveolar and microvascular injury. CONCLUSIONSHyperoxia-induced BPD-PH is associated with reduced Baf60c, increased Smarcc2, and suppressed PI3K-Akt-mTOR signaling in PMVECs. Baf60c may indirectly regulate this pathway through Smarcc2. Endothelial Baf60c is a potential therapeutic target in BPD-PH. Novelty and RelevanceO_ST_ABSWhat Is New?C_ST_ABSA neonatal hyperoxia BPD-PH model was characterized with adverse hemodynamic and pulmonary vascular endpoints together with PMVEC functional impairment. Hyperoxia downregulates Baf60c, upregulates Smarcc2, and suppresses PI3K-Akt-mTOR signaling in PMVECs. Baf60c interacts with Smarcc2 without direct PI3K binding. PMVEC-specific Baf60c overexpression via superficial facial vein AAV delivery ameliorates pulmonary hypertension. What Is Relevant?BPD-PH is a developmental pulmonary hypertension phenotype in which pulmonary vascular resistance and right ventricular load are measurable with RVSP and Fulton index, consistent with Group 3 PH biology. SWI/SNF-mediated chromatin remodeling in pulmonary endothelium may link neonatal oxygen injury to impaired angiogenic endothelial function. Clinical/Pathophysiological Implications?Endothelial Baf60c deficiency may contribute to pulmonary vascular rarefaction after neonatal hyperoxia. Restoring endothelial Baf60c may improve pulmonary hemodynamics in BPD-PH, although structural lung injury may be only partially reversible.

physiology↗

Genetically informed single-cell and spatial mapping of metabolic programs in human health and disease

Defining cell-type-specific endogenous metabolic features, the spatial distribution of cell-level metabolic states and cellular responses to exogenous metabolites is very important for understanding disease mechanisms. However, existing transcriptome-based metabolic models primarily infer intracellular reaction or pathway-level activities, and therefore cannot directly assess associations between individual metabolite levels and cellular states, particularly for metabolites that act extracellularly as signalling molecules rather than entering cells as metabolic substrates. To overcome this problem, we introduce the gmMAP (Genetically informed metabolite trait mapping across single-cell and spatial tissues), a framework that integrates metabolite GWAS summary statistics with single-cell and spatial transcriptomes to map metabolic programmes at cellular and spatial resolution. Notably, the gmMAP enables the prediction of endogenous metabolic process activation while also revealing intrinsic associations between exogenous metabolites and diverse cellular functional states. To further capture the connectivity of cellular metabolic networks, we incorporated a constraint-based metabolic flux model to evaluate global metabolic activity. To evaluate the accuracy and generalizability of gmMAP, we applied the framework across representative biological contexts spanning human development, physiological homeostasis, inflammation and cancer. In human kidney development, the gmMAP captured dynamic metabolic programmes, which was validated using paired transcriptomic and metabolomic reference datasets, supporting its reliability in metabolite identification and metabolic-flow inference. At the organ level, the gmMAP reconstructed spatial metabolite distribution patterns across 17 mouse organs under homeostatic and autoimmune inflammatory conditions, and further extension of gmMAP to 24 normal human tissues generated a multi-scale metabolic atlas at both organ and cellular resolutions. In disease settings, gmMAP revealed metabolic reprogramming across 29 pan-cancer cell populations, and identified potential links between exogenous metabolites and inflammation-associated stromal metabolic remodelling in ulcerative colitis. Together, gmMAP can consistently connect genetically informed metabolite traits with cell states, spatial tissue organization and disease pathology.

genomics↗

Megalin deficiency perturbs retinal homeostasis and impairs cathepsin D processing and phagosome-lysosome maturation in the retinal pigment epithelium

The multiligand endocytic receptor, megalin (LRP2), is expressed in the retinal pigment epithelium (RPE) and patients lacking the receptor develop high myopia. Despite its established role in retinal development, the contribution of megalin to retinal homeostasis in the normally developed/mature eye remains poorly understood. Here, we investigated megalin function using an inducible knockout mouse (KO) model and human iPSC-derived RPE with megalin knockdown (KD) to distinguish post-developmental homeostatic functions from developmental effects. In vivo, megalin ablation caused progressive retinal degeneration and visual impairment, with morphological abnormalities in the RPE but no changes in myopia-associated ocular phenotypes including axial length and intraocular pressure. Proteomic profiling of megalin-KO RPE revealed reduction of autophagy-related proteins. In line with this, megalin deficiency was associated with accumulation of pro-cathepsin D, and perturbed rhodopsin turnover. This was supported in vitro, where trafficking of photoreceptor outer segment (POS) containing phagosomes to lysosomes was reduced, suggesting disturbed phagosome maturation. Megalin KD did not measurably impair initial uptake of POS discs, but delayed rhodopsin degradation, indicating defective post-ingestion processing. Together, these findings establish megalin as a key regulator of retinal homeostasis in the mature eye by controlling phagosome-lysosome fusion in the RPE and suggest that megalin dysfunction contributes to slowly progressive retinal degeneration. This positions megalin as a potential therapeutic target in lysosomal degenerative diseases in the retina.

Cell Biology↗

A Structural Principle for Macroscopic Neural Dynamics Correlations

A central question in neuroscience is how the brains structural connectivity gives rise to its emergent, correlated dynamics. These large-scale dynamical correlations underlie functional networks that support cognitive functions. Here, we identify coupling correlation--the similarity between the input connectivity profiles of brain regions--as a key structural determinant of macroscopic neural dynamical correlation. Using dynamical mean-field theory (DMFT) and numerical simulations of random neural network models, we demonstrate that coupling correlation quantitatively governs dynamical correlation. The functional form of this structure-function mapping is dictated by the eigenvalue spectrum of the coupling correlation matrix: networks with bulk eigenspectra exhibit an exact linear relationship, whereas biologically plausible long-tailed spectra yield an approximately linear mapping except when the magnitude of coupling correlation approaches unity. Particularly, a long-tailed spectrum is necessary to reproduce the appropriate magnitude and size-invariance of coupling correlations observed in empirical data, thereby sustaining non-vanishing dynamical correlations that may support brain function in large systems. The theoretical prediction of approximate linearity is consistently validated using empirical datasets that include both structural coupling and neural dynamics in humans, mice, and Drosophila. Together, these results provide a mechanistic and quantitative framework linking macroscopic brain network structure to emergent neural dynamics--an essential step toward a theory of structure-function relationship in the brain. Significance StatementHow the brains wiring gives rise to its coordinated activity is a fundamental unsolved problem in neuroscience. Prior work has identified correlations between structural and functional connectivity, but these relationships lacked a mechanistic, first-principles explanation. Here, we derive an analytical framework using Dynamical Mean-Field Theory and random neural network models to show that a single structural statistic--coupling correlation, the similarity between the input connectivity profiles of brain regions--linearly and causally determines the magnitude of correlated neural dynamics. We further show that a long-tailed eigenvalue spectrum in biological structural connectivity is necessary to sustain the strong, size-invariant functional correlations observed across species. Validated in humans, mice, and Drosophila using multiple imaging and connectome modalities, this principle may provide a quantitative bridge between structural connectomics and emergent brain dynamics, with implications extending to a broad class of complex networked systems.

neuroscience↗

Double-strand break end configuration and 3D genome architecture are crucial for chromosomal translocation

Chromosomal translocations originate from erroneous rejoining of DNA double-strand break (DSB) ends and mechanisms of their formation remain largely unknown. Here we reveal DSB end configuration and three-dimensional (3D) genome architecture cooperatively shape both translocation frequency and junctional indel pattern. By integrating multiplex CRISPR/Cas9 editing with an optimized translocation assay, we find that translocation frequency correlates with spatial proximity. In addition, templated insertions emerge as a defining structural feature of translocation junctions induced by Cas9-mediated staggered cleavage and confirmed by DISCOVER-seq. Interestingly, translocation frequency is correlated with cleavage geometry. Finally, engineered Cas9 variants with altered DSB end configurations enable programmable modulation of junctional indel patterns. These findings shed significant insights into mechanisms of recurrent chromosomal rearrangements in human diseases and have interesting implications in safe applications of genome editing.

cell biology↗

Donor Age and Oligosaccharide Structure Jointly Shape the Gut Microbiome Function

Non-digestible oligosaccharides are widely used as prebiotics, yet structurally related glycans can elicit distinct gut microbiome responses. Here, we combined controlled ex vivo fermentation, deep DIA metaproteomics, and targeted metabolomics to determine how oligosaccharide structure and donor age shape microbiome function. Stool microbiomes from 18 healthy donors across three age groups were cultured with seven structurally related oligosaccharides from two glycan families, fructo-oligosaccharides (FOS) and galactosyl-sucrose derivatives (GSD). We found that oligosaccharide structure organized a functional response landscape rather than simply separating substrates into broad prebiotic classes. Structurally related glycans produced more similar response profiles overall, yet closely related FOS substrates remained functionally distinguishable, indicating that subtle structural differences were resolved by the microbiome as graded functional changes. These structure-responsive functions were further associated with producer-level reorganization relative to baseline, while targeted enzyme-level analyses indicated that substrate-specific CAZyme responses could also reflect altered functional investment within shared producer backgrounds. Despite these substrate-specific entry processes, network analysis revealed convergence onto shared downstream physiological states enriched for translation, amino-acid biosynthesis, secretion/export, and chemotaxis-related pathways. Across treatments, major short-chain fatty acids increased while mucin glycan degradation-associated markers decreased, suggesting coordinated shifts toward saccharolytic metabolism and reduced host-glycan foraging. Tryptophan-associated metabolism was also consistently linked to primary fructan processing, accompanied by higher extracellular tryptophan availability. Donor age modified selected microbial functional axes and enzyme-metabolite coupling relationships rather than the overall direction of core fermentation outputs. In particular, oligosaccharides attenuated an Methanobrevibacter smithii (M. smithii) and M00567 methanogenesis-related signature in microbiomes from older adults and altered age-dependent relationships between butyrate-pathway enzymes and extracellular butyrate levels. Together, these findings show that oligosaccharide structure determines how gut microbial communities organize carbohydrate processing and downstream functional states, while donor age reshapes the taxonomic and metabolic context of these responses. This work provides a mechanistic framework for structure-aware and age-aware precision prebiotic design.

microbiology↗

Desert hedgehog enhances endothelial resilience and prevents atherosclerosis by mitigating PAI-1 signaling

BACKGROUNDAtherosclerotic cardiovascular disease remains the leading cause of death worldwide. Most current pharmacotherapies target conventional risk factors that promote atherosclerosis (e.g., hyperlipidemia) rather than intrinsic resilience factors that protect against atherosclerosis in the face of risk factors. Here, we investigated the role of desert hedgehog (DHH), a canonical ligand of the hedgehog signaling pathway, as a novel resilience factor that restrains endothelial mesenchymal transition (EndoMT) and protects against atherosclerosis. METHODSSingle-cell RNA sequencing (scRNA-seq) was performed on atheroprone and atheroprotective regions of the ApoE knockout mouse aorta to identify mechanoresponsive genes associated with atherosclerosis. Endothelial cell-specific Dhh knockout mice were subjected to partial carotid ligation and hypercholesterolemic conditions to investigate the role of endothelial Dhh in atherosclerosis progression. scRNA-seq, bulk RNA sequencing, endothelial lineage tracing, immunoprecipitation-coupled mass spectrometry, and surface plasmon resonance were used to in-vestigate the role and mechanism of DHH in EndoMT. Pharmacological interventions and recombinant DHH administration were performed in vivo to evaluate therapeutic potential of DHH targeting. DHH expression was also examined in human atherosclerotic arteries and serum samples from patients with coronary artery disease. RESULTSDHH protein expression was enriched in arterial endothelium from mice, porcine, and humans. However, DHH expression was significantly reduced in atherosclerotic arteries and serum from patients with coronary artery disease. scRNA-seq of atheroprone and atheroresistant region of mouse aorta identified Dhh as a novel mechanoresponsive gene enriched in aortic regions exposed to unidirectional laminar flow. Endothelial cell-specific Dhh knockout (DhhecKO) mice exhibited increased atherosclerotic lesion area, large necrotic cores, and reduced collagen content following partial carotid ligation. Similarly, under hypercholesterolemic conditions, both male and female DhhecKO mice showed aggravated atherosclerosis progression. scRNA-seq of DhhecKO mouse aortas revealed an increased proportion of endothelial cells undergoing mesenchymal transition, indicating enhanced EndoMT. These findings were corroborated by bulk RNA-sequencing of DHH depleted HUVECs and endothelial lineage tracing in inducible DhhecKO mice. Mechanistically, DHH directly interacted with plasminogen activator inhibitor type 1 (PAI-1) and suppressed PAI-1-induced EndoMT. PAI-1 promoted EndoMT in ECs through activation of canonical TGF-{beta} signaling (SMAD2/3) and noncanonical AKT/ERK1/2 signaling via interaction with low-density lipoprotein receptor-related protein (LRP1). Neutralization of PAI-1 or inhibition of LRP1, AKT/ERK1/2, or SMAD3 signaling abolished DHH deficiency-induced EndoMT. DHH competitively inhibited PAI-1 binding to LRP1, thereby attenuating downstream pro-EndoMT signaling. Intriguingly, treatment with PAI-1 inhibitor TM5275 mitigated endothelial Dhh deficiency induced EndoMT in vivo. Of translational relevance, recombinant mouse DHH protein administration reduced atherosclerosis progression, stabilized plaque, and decreased the expression of EndoMT markers in ApoE knockout mice. CONCLUSIONSDesert hedgehog (DHH) is an intrinsic endothelial cell-enriched resilience factor that protects against EndoMT and atherosclerosis by preventing PAI-1 signaling. The present study implicates endothelial DHH as a potential therapeutic target for atherosclerotic cardiovascular disease. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=163 SRC="FIGDIR/small/729715v1_ufig1.gif" ALT="Figure 1"> View larger version (50K): org.highwire.dtl.DTLVardef@194c8a3org.highwire.dtl.DTLVardef@1004d52org.highwire.dtl.DTLVardef@d47c73org.highwire.dtl.DTLVardef@368866_HPS_FORMAT_FIGEXP M_FIG C_FIG Desert hedgehog (DHH) is an intrinsic endothelial cell-enriched resilience factor that protects against EndoMT and atherosclerosis by preventing PAI-1 binding to LRP1 and downstream AKT/ERK, as well as SMAD2/3 signaling. Clinical PerspectiveO_ST_ABSWhat Is New?C_ST_ABSO_LIDHH was identified as a flow-responsive resilience gene that is downregulated by disturbed flow in endothelial cells. C_LIO_LIEndothelial-specific deletion of Dhh promoted endothelial-to-mesenchymal transition (En-doMT) and atherosclerosis. C_LIO_LIDHH directly interacts with PAI-1 and preclude PAI-1 mediated pro-EndoMT signaling. C_LI What Are the Clinical Implications?O_LIDHH maintains endothelial homeostasis during atherosclerosis. C_LIO_LITargeting endothelial DHH-PAI-1 axis may represent a potential therapeutic strategy to reduce EndoMT and limit plaque progression. C_LIO_LILower circulating DHH level may serve as a potential biomarker of endothelial dysfunction and plaque vulnerability in atherosclerotic disease. C_LI

biochemistry↗

GalaxyVS: Exploring 100-Billion Compounds in Seconds

We present GalaxyVS, a hardware-software co-designed virtual screening framework built to explore the 100-billion commercially accessible chemical space in seconds, deployed at the National Supercomputing Center in Tianjin. Built upon the dense vector retrieval paradigm of DrugCLIP, GalaxyVS bypasses the structural dependencies and computational overhead of classical docking to enable rapid screening against experimentally determined as well as geometrically feasible pockets on AlphaFold-predicted structures. To scale this paradigm to the 100-billion level, the system must overcome the significant computational burden of offline representation encoding, critical memory and I/O bottlenecks during online retrieval, and the risks of diversity collapse and precision loss within final screening results. Utilizing the heterogeneous supercomputing infrastructure, GalaxyVS accelerates the offline encoding through deep operator adaptations and resolves online retrieval bottlenecks via disk-native vector indexing coupled with in-memory staging to ensure both broad accessibility and high throughput. Concurrently, a two-stage refinement protocol effectively mitigates diversity collapse and ensures high-fidelity affinity ranking. Consequently, GalaxyVS achieves a daily scoring throughput of 1.5 x 1016 target-ligand pairs, representing a six-orders-of-magnitude leap over previous supercomputing records. Driven by this throughput, we screened nearly 100,000 protein structures across six species against the 100-billion compound library in just 16 hours. The resulting comprehensive cross-species interaction landscape, GalaxyDB, will be openly released at https://galaxyvs.drugclip.com.

bioinformatics↗

Multimodal dynamics control activity of a glial glutamate transporter

Membrane transporters move polar solutes across lipid bilayers to regulate cellular metabolism, signaling, and drug distribution. These proteins operate via an alternating-access mechanism, cycling between extracellular-, intermediate-, and intracellular-facing conformations. The human excitatory amino acid transporter 1 (EAAT1) protects neurons from excitotoxic damage by mediating the uptake of glutamate and aspartate into glial cells. Defects in EAAT1 function result in numerous pathologies, including epilepsy and ataxia, suggesting that positive modulation of these transporters might ameliorate glutamate neurotoxicity. However, developing EAAT1 activators requires understanding the timing of conformational changes, which remain largely unexplored. Here, we establish an experimental platform that combines single-molecule Forster resonance energy transfer (smFRET) to monitor real-time conformational dynamics, single-transporter activity assays to correlate dynamics with function, and cryogenic electron microscopy (cryoEM) to visualize discrete conformations at high resolution. This platform enables detection of [A]ngstrom-scale movements of single transporter molecules in real time, revealing that EAAT1 intersperses rapid conformational dynamics with long pauses. Slow and fast dynamics can be modulated by substrates, membrane composition, and mutations, and are correlated with the enrichment of specific structural states. We leverage this platform to investigate an EAAT1 mutation associated with severe episodic ataxia and show that it inhibits transport by stabilizing a paused cytoplasm-facing conformation. These results identify multimodal dynamics as an intrinsic, regulatable feature of EAAT1 function and, therefore, a potential therapeutic target. Henceforth, our integrated platform will facilitate investigations of other regulatory factors, including the effects of small-molecule and lipid modulators on the transport cycle.

biophysics↗

Distinct senescent β-cell senotypes differentially drive islet aging and dysfunction

Biological aging greatly impacts the bodys ability to handle glucose, and represents a major risk factor the development and progression of type 2 diabetes (T2D). Nonetheless, despite advances in cellular senescence research and the development of new senolytic therapies, the heterogeneity of cellular senescence in the human endocrine pancreas, as well as its roles in normal aging, remains to be elucidated at the single-cell level. Here, we performed single-cell-resolved spatial proteomics and transcriptomics on intact pancreas from 26 donors (ages 20-80) and multiplexed single-cell RNA sequencing and functional assays on dispersed islets from 14 donors (ages 34-69). We identify two discrete SnC subpopulations distinguished by relative expression of CDKN1A and CDKN2A. CDKN1A senescent cells (SnCs) exhibit loss of {beta}-cell identity, impaired insulin secretion, and a proinflammatory SASP associated with increased islet immune infiltration. In contrast, CDKN2A SnCs retain transcriptional identity and functional competence, with lower inflammatory signaling. Together, these findings identify heterogeneous and functionally divergent senotypes in the human pancreas, distinguishing an adaptive (CDKN2A) from a maladaptive (CDKN1A) senescence program, thus providing a mechanism-guided framework for senescence-targeted therapies in T2D.

cell biology↗

Microbiome-mediated lauric acid turnover contributes to colonization resistance against Ralstonia in the tomato rhizosphere

Host-associated lipids shape plant-microbiome interactions, but their microbiome-mediated turnover and role in pathogen exclusion are not fully understood. In tomato, lauric acid (C12:0) occurs across root-associated compartments, and its abundance at the root-soil interface is linked to soil-dependent differences in rhizosphere community composition and Ralstonia solanacearum colonization. Lauric acid promotes Ralstonia motility and virulence in vitro while inhibiting some beneficial lauric-acid-sensitive taxa, especially Gram-positive antagonists. In disease-suppressive soils, rhizosphere communities enriched in lauric-acid-degrading taxa are associated with lower local lauric acid levels and reduced pathogen colonization, suggesting community-dependent buffering of the rhizosphere lauric acid pool alongside other protective microbiome functions. Soil perturbation, microbiome transplantation, gnotobiotic SynCom reconstruction, and isotope tracing provide convergent evidence that microbiome-mediated lauric acid turnover contributes to colonization resistance and helps explain how rhizosphere lipid chemistry influences pathogen invasion outcomes in tomato, revealing an ecologically grounded protective mechanism for pathogen management.

microbiology↗

Regulation of the Na-K-2Cl cotransporter NKCC2 by ubiquitylation

NKCC2, localized to the apical membrane of thick ascending limb epithelial cells, is essential for renal salt handling and systemic electrolyte homeostasis. NKCC2 undergoes extensive ubiquitylation, with the E3 protein ligase Nedd4-2 implicated as a key regulator. However, progress has been limited by challenges expressing NKCC2 in mammalian cell lines, hindering mechanistic studies of NKCC2 ubiquitylation. Therefore, the aims of this study were to develop a mammalian cell model enabling mechanistic investigations of NKCC2 ubiquitylation, including the role of Nedd4-2 and the functional consequences of site-specific modification. A tetracycline-inducible MDCKI cell line was generated expressing human NKCC2 and used to assess Nedd4-2-dependent and site-specific ubiquitylation of NKCC2 using biochemical, imaging, and functional assays. The MDCKI cell line demonstrated stable, inducible expression of full-length human NKCC2. In this cell line, mutating the ubiquitylation site at K871 increased membrane abundance and uptake activity, without altering internalization rates. Nedd4-2 co-immunoprecipitated with NKCC2, and Nedd4-2 deletion increased total, but not membrane NKCC2 abundance. In summary, ubiquitylation on NKCC2 at K871 plays a key role in controlling NKCC2 membrane localization and thus function. Although Nedd4-2 can modulate NKCC2 abundance, it is not involved in NKCC2 trafficking. We conclude that the generated cell line provides a robust model for mechanistic studies of NKCC2 and will aid studies examining posttranslational regulation of NKCC2.

molecular biology↗