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Meng, X.

Publications and source records attributed to Meng, X..

At least 37 records · Page 2Linked to original sources

Sex-specific Genetic Regulatory Effects in Chickens

Sexual dimorphism is a defining vertebrate feature, yet its sex-specific molecular architecture remains poorly understood. Here we established a sex-balanced, uniformly reared chicken cohort to map this landscape, integrating individual whole-genome sequencing with 7,969 bulk and 779,380 single nucleus transcriptomes across 32 tissues from 280 birds. We identified 495,098 independent expression quantitative trait loci for 20,194 genes, including 10,937 loci modulated by cell-type composition. Notably, 340 genes were regulated by 449 loci in a sex-dependent manner, significantly enrichment in endocrine tissues like adipose and the adrenal gland. Furthermore, we fine-mapped 1,219 structural variants, demonstrating their unique roles to tissue- and sex-specific expression beyond SNPs. Ultimately, we showed the utility of these regulatory effects in elucidating the molecular basis of metabolism and complex traits in both chickens and humans. This comprehensive atlas of regulatory effects provides profound insights into the genomic and molecular basis of sexual dimorphism in vertebrates.

genomics↗

CellSwarm: LLM-Driven Cell Agents Recapitulate Tumor Microenvironment Dynamics and Sense Indirect Genetic Perturbations

Agent-based models of the tumor microenvironment (TME) traditionally rely on hand-coded rules that cannot generalize beyond their programmed logic. Here we present CELLSWARM, a framework that replaces rule-based cell decision-making with large language model (LLM)-driven autonomous agents. Each simulated cell maintains persistent state, 14 signal pathways, and a memory stream, with an LLM serving as its cognitive core. Using structured knowledge bases for cancer-specific context, CELLSWARM recapitulates TNBC microenvironment composition with fidelity comparable to hand-coded rules (Jensen-Shannon divergence 0.144 vs. 0.146; P=0.012 vs. random, Mann-Whitney U test). Beyond matching rule-based performance, LLM-driven agents demonstrate three capabilities absent from rule-based models: cross-cancer generalization by swapping knowledge base entries, treatment response prediction concordant with clinical data (anti-PD-1: 17.6% simulated vs. 21% clinical), and sensing of indirect genetic perturbations that propagate through intermediate signaling cascades (IFN-{gamma} KO: Agent +15.7% vs. Rules +0.3%; P=0.005). CELLSWARM demonstrates that LLM-driven cell agents can recapitulate and extend TME simulation beyond the reach of hand-coded rules.

systems biology↗

Unwinding of RNA G-quadruplexes induces mouse and human totipotency

Totipotent stem cells (TotiSCs) have significant application prospects in regenerative medicine and assisted reproductive technologies. The mRNAs of totipotency-related genes are rich in G-quadruplex (G4) structures, while the G4 density of pluripotency-related genes mRNAs is relatively low, suggesting a potential functional link between RNA G4s and the totipotent state. Nevertheless, how G4s are involved in the establishment or maintenance of mouse and human totipotency remains poorly understood. Here, we demonstrate that FC3, a small-molecule RNA G4 unwinder, enables efficient induction and maintenance of mouse and human TotiSCs (mG4TotiSCs and hG4TotiSCs). These FC3-induced TotiSCs closely recapitulate the molecular features of 2-cell-stage blastomeres via transcriptomic and epigenomic profiling. Functionally, both mG4TotiSCs and hG4TotiSCs exhibit totipotent capacity: they differentiate into embryonic and extraembryonic lineages in vitro and in chimeric embryos; moreover, they autonomously self-organize into blastocyst-like structures without exogenous signalling. Mechanistically, we identify that Gata2 mRNA, a G4-containing transcript, is essential for FC3-mediated reprogramming. Genetic disruption of Gata2 would abolish totipotency induction. Collectively, RNA G4 unwinding is a new regulatory axis governing totipotency acquisition and maintenance, providing insight into the functional interplay between nucleic acid secondary structures and cell fate plasticity.

cell biology↗

In Vivo Surface Reconstruction of Three Signal-defined Intracortical Layers Using 5T 3D FLAIR MR Imaging

BackgroundIn vivo whole-cortex quantification of intracortical signal-defined layering on the routinely acquired structural MRI remains limited. PurposeTo develop and validate an automated framework to reconstruct three intracortical signal-defined layers from 5T three-dimensional (3D) T2-weighted fluid-attenuated inversion recovery (FLAIR) and to characterize whole-cortex morphometrics and regional organization across a prespecified cortical organizational framework. Materials and MethodsIn this retrospective study, 5T 3D FLAIR images were acquired between February and July 2024. Brain Multi-Layer Surface Reconstruction (BrainMLSR) reconstructed three intracortical signal-defined layers, and derived intracortical layer thickness and surface area measures and ratios. Performance was evaluated against manual annotations and assessed for test-retest repeatability (n=13) and cross-site feasibility (n=2). Paired two-tailed t-tests and linear mixed-effects models were used. A proof-of-concept analysis compared Heschls gyrus ratios between 19 patients with temporal lobe epilepsy (TLE) and 19 age-matched healthy controls (HC). ResultsA total of 270 healthy participants (mean age, 54.4{+/-}14.5 years; 146 men) were included. Agreement with manual hypointense-layer annotations was high (Dice, 0.960{+/-}0.003), and was similar in the cross-site dataset (Dice, 0.954{+/-}0.009). In the test-retest dataset, average symmetric surface distance was less than 0.1 mm. Across prespecified systems, thickness and surface area ratios varied by region; within an auditory-perisylvian hierarchy, banksSTS showed a localized turning point with an increased hyperintense layer thickness ratio and decreased hypointense layer thickness ratio, accompanied by inflections in surface area ratios (P < .001). In bilateral Heschls gyrus, hypointense (left: 0.619{+/-}0.262 vs 0.881{+/-}0.102; right: 0.607{+/-}0.310 vs 0.907{+/-}0.141 mm) and isointense (left: 0.406{+/-}0.225 vs 0.678{+/-}0.128; right: 0.478{+/-}0.232 vs 0.808{+/-}0.176 mm) layer thicknesses were lower in TLE than in HC (all P<.001). ConclusionBrainMLSR enabled accurate and repeatable in vivo reconstruction of three intracortical signal-defined layers from a single 5T 3D T2-weighted FLAIR acquisition and provided whole-cortex boundary-based morphometry with interpretable regional organization. Key ResultsO_LIIn this retrospective study of 270 participants, Brain Multi-Layer Surface Reconstruction (BrainMLSR) showed high agreement with hypointense-layer annotations (Dice, 0.960{+/-}0.003). C_LIO_LIWithin an auditory-perisylvian hierarchy, the hyperintense-layer thickness ratio peaked (0.620{+/-}0.003) and the hypointense-layer ratio was the lowest (0.156{+/-}0.002) in the bank of the superior temporal sulcus (P < .001). C_LIO_LIIn a proof-of-concept analysis, patients with temporal lobe epilepsy (vs healthy controls) had higher hyperintense-layer thicknesses ratio in the left hemisphere (0.523{+/-}0.085 vs 0.417{+/-}0.036, P<.001). C_LI SummaryAn automated multiple-layer surface reconstruction framework (BrainMLSR), applied to 5T 3D T2-weighted FLAIR images, produced reproducible whole-cortex, signal-defined laminar morphometry and demonstrated coherent patterns across prespecified cortical organizational framework.

neuroscience↗

Forward genetics reveals microsporidian drug targets and recombination-based resistance

Microsporidia are a diverse group of intracellular fungal parasites that infect humans and many agriculturally important animals. Several microsporidia inhibitors have been characterized, but the targets of these inhibitors in microsporidia have not been confirmed, and the mechanisms by which microsporidia evolve resistance are unknown. Using the model organism Caenorhabditis elegans and its naturally occurring microsporidian parasite Nematocida parisii, we developed a technique to continually passage infected animals for multiple generations under increasing inhibitor concentrations. We obtained multiple independent N. parisii strains that are specifically resistant to the microsporidia inhibitors albendazole or dexrazoxane. The albendazole-resistant strains all contained either heterozygous or homozygous mutations in beta-tubulin, with several strains containing beta-tubulin variants that have been observed in other albendazole-resistant organisms. Strains containing homozygous variants are resistant to several albendazole analogs, whereas the heterozygous variant-containing strains are only resistant to albendazole. Several of the albendazole-resistant strains also contain mutations in alpha-tubulin. The dexrazoxane-resistant strains all contain heterozygous mutations in topoisomerase II and several of these mutations occur in the binding site of this inhibitor. By mapping heterozygosity of the resistant strains across the N. parisii genome, we observed loss of heterozygosity spanning the beta-tubulin locus in the albendazole-resistant strains containing homozygous beta-tubulin variants. Our study demonstrates the utility of forward genetics for identifying microsporidian drug targets. We also find that drug resistance arises through de novo heterozygous mutations that can subsequently become homozygous, likely via mitotic recombination.

microbiology↗

Spatiotemporal Mapping of Tertiary Lymphoid Structure Heterogeneity Shapes Immune Niches and Clinical Outcomes in Intrahepatic Cholangiocarcinoma

Intrahepatic cholangiocarcinoma (iCCA) is a highly lethal malignancy with limited therapeutic options. The spatial architecture and functional diversity of tertiary lymphoid structures (TLSs) in iCCA remain unclear. Here, we present a multimodal spatial atlas of TLSs and identified Intra-tumoral TLSs (iTLSs) as independent prognostic markers. Bulk proteomic profiling of 214 discovery and 155 validation cases identified a four-tier TLS-based TME classification system and supported development of a TLS-predictive random forest classifier. Imaging mass cytometry revealed that iTLS tumors harbor structured immune architectures, where M1-like tissue-resident macrophages (RTMs), dendritic cells, and CXCL13 CD4 T cells co-localize to form antigen-presenting neighborhoods (apc-CNs) spatially coupled to TLS core regions (TLScore-CNs). Single-cell spatial transcriptomics further resolved 61 TLSs into 14 spatial niches and defined a pseudo-temporal maturation continuum: aggregated, activated, and post-activated. Intra-niche communication, primarily mediated by ifnCAFs, iCAFs, and CXCL12 macrophages, evolved dynamically with maturation. Single-nucleus RNA-sequencing combined with Tangram-based spatial mapping revealed CXCL12 macrophages and iCAFs forming a peripheral band in aggregated TLSs, while ifnCAFs infiltrated TLS interiors during activation. These findings define TLS heterogeneity and provide insights for stroma-directed immunotherapy. TeaserAn atlas of tertiary lymphoid structures reveals immune-stroma interactions in Intrahepatic cholangiocarcinoma.

immunology↗

A gastric microbial chromatin remodeler drives gastric cancer progression and immune evasion by reprogramming the host epigenome

Emerging evidence highlights the crucial role of microbial communities in modulating cancer development and progression. In gastric cancer (GC), we identify Streptococcus anginosus (SA) as a tumor-resident oncobacterium that drives both tumor progression and immune evasion. We define a novel mechanism in which SA secretes extracellular vesicles (saEVs) that translocate the bacterial chromatin remodeler saSNF2 into host cell. There, saSNF2 partners with host transcription factor TEAD1--through its ATPase activity and participation in BAF complex assembly--to coordinately activate oncogenic transcription. This transkingdom interaction upregulates the palmitoyltransferase ZDHHC11, which in turn stabilizes PD-L1 via palmitoylation to establish an immunosuppressive niche, while also amplifying other TEAD1 target genes to fuel tumor progression. Functionally, saEVs promote tumor growth and limit CD8+ T-cell infiltration in vivo. Strikingly, pharmacological inhibition of ZDHHC11 reverses immune evasion and synergizes with anti-PD-1 checkpoint blockade. Our results establish SA as a multifaceted driver of GC and reveal the saSNF2-ZDHHC11 axis as a promising target to potentiate immunotherapy.

cancer biology↗

An ancient transcription factor functions as the master regulator of primary cilia formation

How ancient transcription factors are repurposed during evolution to drive the functional diversification of conserved organelles remains a fundamental question in biology. Although highly conserved in basic morphology, eukaryotic cilia vary extensively in their sizes and functions. Previously, we showed that an evolutionarily ancient transcription factor, X chromosome-associated protein 5 (Xap5), controls motile ciliogenic transcriptional programs during mouse spermatogenesis (Wang et al., 2025). Here we show that Xap5 functions as the master regulator of primary ciliogenesis. Xap5 associates with the nuclear protein Non-POU domain-containing octamer-binding protein (Nono) to form a regulatory module that directly binds and activates the transcription factors Sox5 and Sox9. Genetic ablation of Xap5 or Nono impairs primary ciliogenesis, and loss of Sox5 disrupts the downstream ciliogenic program, consistent with the established role of Sox9. Collectively, our results provide new insight into how complex ciliary transcription factor networks determine ciliary diversity during evolution, and suggest that defects in this regulatory axis may contribute to the etiology of human ciliopathies.

cell biology↗

A 5'-end based Molecular Marker Enables Identification and Deployment of a Functional Rpi-vnt1.1 Allele for Durable Late Blight Resistance in Potato

Potato (Solanum tuberosum) is a globally important food crop, yet its production is severely threatened by late blight, caused by Phytophthora infestans. Deploying resistance (R) genes in breeding programs offers a sustainable approach for disease management. Rpi-vnt1.1 is a broad-spectrum R gene cloned from wild Solanum species Solanum venturii. Here, we developed a PCR marker targeting the 5'-end extension of Rpi-vnt1.1, which enables efficient and specific detection of the resistant alleles. Screening of advanced breeding lines from the International Potato Center (CIP) identified line C1848, which carries a functional Rpi-vnt1.1 allele. Inoculation assays confirmed C1848 confers strong resistance to P. infestans. Subsequent functional assays, including RNAi-mediated silencing in C1848 and heterologous expression in Nicotiana benthamiana, demonstrated that this resistance is specifically mediated by the Rpi-vnt1.1 allele. This specific marker provides a rapid, low-cost tool for marker-assisted breeding, facilitating the deployment of potato cultivars carrying Rpi-vnt1.1.

plant biology↗

A structural and regulatory framework for Atg9-containing vesicle formation and their Atg1-dependent remodelling during autophagy initiation

Autophagy is a complex intracellular degradation pathway that depends on the coordinated interplay between the core autophagy machinery and diverse membrane sources to drive the de novo formation of double-membrane vesicles, known as autophagosomes. Golgi-derived Atg9-containing vesicles are essential for this process, delivering membranes to the pre-autophagosomal structure (PAS). These vesicles contain the transmembrane proteins Atg9 and Atg27 and the peripheral membrane protein Atg23; however, the nature, function, and regulation of their interactions remain poorly understood. Here, we systematically dissect the molecular interactions between Atg9, Atg23 and Atg27, and uncover their regulation in space and time. The bipartite binding mode by which Atg23 engages Atg9 provides a structural model for how Atg23 promotes vesicle budding. Furthermore, Atg1-dependent phosphorylation of Atg9 remodels its interactions with Atg23 and Atg27 at the PAS to support autophagy initiation. Together, these findings establish a molecular and regulatory framework for the earliest steps of autophagy.

biochemistry↗

Gut microbial composition modulates food-specific CD4+ T cells in food allergy

The growing food allergy epidemic is thought to be related to changing environmental factors, particularly changes in the gut microbiome. While prior work has demonstrated that food allergy can be modulated by gut microbes, little is known about how food allergen-specific CD4+ T cells are affected by gut microbial composition. Here, we report that food allergy severity differs between mice obtained from two different specific pathogen-free mouse vendors (Jackson Labs [Jax] and Taconic Biosciences [Tac]). Mice from Tac develop diarrhea and anaphylaxis after fewer allergen exposures than mice from Jax. Using food allergen peptide:MHCII tetramers, we also find that Tac mice have fewer allergen-specific regulatory T cells in the small intestine compared to mice from Jax. In addition, Tac mice have a greater abundance of small intestinal mucosal mast cells and increased intestinal permeability. The increased food allergy severity phenotype is transferable via co-housing, which corresponds to a shift in Jax microbial communities towards those found in Tac mice. Our findings demonstrate for the first time that food allergen-specific Treg cells can be modulated by gut microbial community composition, which in turn is correlated to food allergy severity.

immunology↗

A Druggable Tumor Suppressor and Leukemic Stem Cell Marker

Withdrawal StatementThe authors have withdrawn this preprint because the co-authors were not in agreement about posting the work in its current form. The authors request that this work not be cited. Please contact the corresponding author (Dr. Xunlei Kang, kangxu@health.missouri.edu) with questions.

cancer biology↗

Enterococcus faecalis delivers Obg GTPase via extracellular vesicles to instigate mTOR activity and promote HCC tumorigenesis

Hepatocellular carcinoma (HCC) is a malignant tumor that has been associated with dysbiosis of the gut microbiota. However, how the gut microbiota plays an oncogenic role in HCC remains largely unknown. Here, we show that Enterococcus faecalis (E. faecalis) is highly enriched in liver tumor tissues and is positively correlated with pathogenesis of HCC. E. faecalis promotes liver cancer cell proliferation, protein translation, cell migration and tumorigenesis. Mechanistically, we found that EF-derived extracellular vesicles (EF-EVs) deliver EF-Obg GTPase to activate host mTOR, thereby promoting liver cancer progression. Intriguingly, the EF-Obg protein exerts its influence on the mTOR pathway via a Ras-like G domain involved in GTP binding. EF-Obg exhibits a striking homology with the G1 site of the G domain of Rheb, a key positive regulator of mTOR. Obg gene is critical for E. faecalis to activate mTOR to promote hepatocarcinogenesis based on an engineered obg knockdown strain by CRISPR interference experiment. Clinically, abundant EF-Obg protein expression is correlated with enhanced activation of mTOR, leading to poor overall survival in HCC patients. Significantly, treatment of mTOR inhibitor Everolimus confers effectiveness in EF-colonized liver cancer orthotopic model, suggesting that Everolimus therapeutic approach can be effective for liver cancer patients with enriched E. faecalis. Taken together, we provide mechanistic and functional evidence to verify a direct causal relationship between tumor-resident E. faecalis enrichment and liver carcinogenesis, revealing that EF-Obg functions as a previously unidentified cross-kingdom activator of mTOR to promote liver tumorigenesis.

cell biology↗

Potato dihaploids uncover diverse alleles to facilitate diploid potato breeding

Commercial potato in North America is a clonal autotetraploid crop, which complicates breeding. Efforts are underway to convert potato to a diploid inbred-hybrid crop that is amenable to additional breeding strategies and allows breeders to more quickly respond to demands for crop improvement. With the goal of preserving haplotypes developed over the last 200 years of selection, diploid potato breeding in the US started with the creation of diploids from tetraploid commercial varieties and advanced breeding lines through prickle pollination. This is an effective but slow method which presents a barrier to entry for individual breeding programs. Therefore, we developed 97 publicly available dihaploids (diploids from prickle pollination of tetraploids) as a resource for diploid breeding in the U.S. These clones contain the majority of alleles in the US breeding population for three market classes: chips, russets, and fresh market reds. To facilitate genomic informed breeding, all clones have been resequenced using short read sequencing technology, and we have developed de novo assemblies based on PacBio HiFi long reads for 20 individuals. As an illustration of how these data will be used in breeding, we explored the maturity locus (StCDF1) and identified 15 different alleles. The majority of dihaploids were heterozygous for early and late alleles, resulting in intermediate maturity. Beyond informing breeding, this data facilitates investigations into potato genomics. The dihaploid population is both highly heterozygous and incredibly diverse on a population level. In particular, there is extensive structural diversity, including copy number variation, segregating within the population. This contrasts with a relatively low genome-wide historical recombination rate ({rho}). Taken together, these findings indicate that potato is highly diverse, with much of that diversity found within long linkage blocks.

plant biology↗

Selectivity filter mutation in NaV1.5 promotes ventricular tachycardia

Loss-of-Function (LoF) mutations in the SCN5A gene, which encodes for the predominant cardiac NaV isoform, NaV1.5 result in either deficiency in the channel expression or function. Impaired NaV1.5 expression and function underlie reduced peak Na+ current (INa) and result in ventricular conduction velocity slowing, predisposing the heart to conduction block and ventricular arrhythmias clinically associated with Brugada syndrome (BrS). Recently, a missense mutation in NaV1.5 selectivity filter (DEKA motif), K1419E (DEEA) has been identified in patients with BrS. Despite early characterization of mutations in selectivity filter of other NaV isoforms, little is known about the impact of DEEA on NaV1.5 function as well as on cardiac electrophysiology. Therefore, we generated a mouse heterozygous for NaV1.5 DEEA to characterize the mutation and investigate the outcome of this functionally deficient NaV1.5 variant on cardiac electrophysiology and arrhythmias. Heterologous expression system and isolated cardiomyocytes revealed lower current density and unchanged NaV1.5 expression in DEEA vs. wild type (DEKA). On the organ level, optical mapping revealed conduction velocity slowing in DEEA hearts, which was accentuated by flecainide resulting in vivo ventricular arrhythmias. Overall, to our knowledge, we provide the first mechanistic insight into the proarrhythmic consequences of a functionally deficient BrS mutation in NaV1.5. Condensed abstractNaV1.5 mutations have been associated with life-threatening arrhythmias. Recently, a selectivity filter mutation (K1419E-NaV1.5, DEKA[->]DEEA), has been linked to Brugada Syndrome (BrS). While DEKA mutations in other NaV isoforms affected channel conductance, the impact of DEEA on NaV1.5 and arrhythmogenesis is unknown. Therefore, we generated mice heterozygous for NaV1.5-DEEA. Cardiomyocytes isolated from DEEA hearts exhibited substantial reduction in sodium current, ventricular conduction slowing and susceptibility to ventricular arrhythmias in vivo that were unmasked by flecainide. Together, DEEA murine model is the first to recapitulate a functional deficiency in NaV1.5, and thus offers insight into the proarrhythmic mechanism of BrS.

physiology↗

Oncogene SETDB1s Dual Role in Endometrial Cancer: Driving Tumor Progression and Immune Escape

Oncogene SETDB1, an H3K9 methyltransferase, drives tumorigenesis in various cancers. Using endometrial cancer (EC) as a model, we discovered SETDB1s dual mechanisms in driving EC tumorigenesis and mediating immune evasion. SETDB1 knockout (SETDB1-/-) tumor-bearing mice exhibited prolonged survival of up to 100 days. Transcriptomic profiling of SETDB1-/- EC cells revealed decreased expression of oncogenes (POLR2A, MSH6, FLNA) and increased expression of tumor suppressor genes (PGR, RERG, ZNF582), which indicates that SETDB1 intrinsically promotes EC tumor proliferation by regulating these downstream genes. SETDB1 repressed repeat elements and the interferon pathway, mediating immune evasion extrinsically by inhibiting anti-tumor macrophage infiltration. ChIP-seq analysis showed SETDB1 binding at pericentromeric regions on many chromosomes and numerous ZNFs. Loss of SETDB1 resulted in abnormal cell division. SETDB1-/- tumors displayed reduced proliferation markers (Ki67, pHH3) and increased macrophage infiltration. Mechanistically, SETDB1 promotes CD47 (a dont-eat-me signal) and represses CCL5 and CXCL9 (macrophage and T-cell recruiting chemokines), contributing to immune evasion. M1-like macrophages killed more SETDB1-/- cells in co-culture. Additionally, SETDB1 knockout in mouse EC cells reduced tumor growth in C57BL/6 mice, with increased macrophage and CD4+ T-cell infiltration. Our results indicates that elevated SETDB1 and its target genes can predict higher tumor grade and worse survival, suggesting that targeting SETDB1 could be a promising therapeutic strategy for EC.

cancer biology↗

Spatial relationship of urban carbon neutrality in Yangtze River Basin

Carbon neutrality needs to be implemented spatially in order to be realized concretely. The distribution of carbon sources and sinks across the national territory is closely related to many factors, such as natural geographical resources, levels of economic and social development, and cultural and historical heritage. It is difficult for many regions to achieve carbon neutrality through their own efforts alone. This article believes that only by achieving local optimal carbon neutrality through a reasonable spatial organization can emissions be ultimately reduced to zero on a national scale. Under the connection of rivers, the basin forms an ecosystem and an economic system with independent characteristics. Carbon sources and sinks within the basin exist within the ecological and economic space of the basin, forming a unique carbon neutrality spatial pattern. This study starts with the spatial distribution status, features and relationships of carbon neutrality elements in the cities of the Yangtze River Basin, and divides the cities into eight types based on their development level, emission level and forest resources, such as high-emission and low-carbon sink developed cities and low-emission and high-carbon sink underdeveloped cities. Different types of cities are proposed with carbon neutrality paths and spatial organization schemes, and it is suggested that the spatial organization demonstration of carbon neutrality in the cities of the Yangtze River Basin can provide a reference for carbon neutrality on a national scale.

ecology↗