Biology subjects

Wei, C.

Publications and source records attributed to Wei, C..

At least 37 records · Page 2Linked to original sources

bioRxiv2025

Complete telomere-to-telomere genomes of cowpea reveal insights into centromere evolution in Phaseoleae

Cowpea (Vigna unguiculata) is a versatile legume crop providing a critical source of grain, vegetable and forage globally. Cultivated cowpea is classified into two main subspecies, subsp. sesquipedalis for fresh-pod vegetable and subsp. unguiculata for grain production. Here, we present two complete telomere-to-telomere (T2T) assemblies for the grain-type inbred lines HJD and vegetable-type FC6 through integrating PacBio HiFi reads, Oxford Nanopore ultra-long reads, and Hi-C data. The T2T genomes demonstrated improved contiguity, completeness, and accuracy compared to existing genomes, revealing clear telomeric and centromeric features. Comparative analysis of the T2T genomes highlighted inversions underlying subspecies divergence in cowpea. Evolutionary analysis uncovered contraction of gene families related to symbiosis in HJD, consist with its reduced root nodules compared to FC6. Distribution and composition of tandem repeat arrays and transposable elements in centromeric regions were largely conserved in cowpea, but displayed pronounced variation among Phaseoleae. Furthermore, frequent shifts of centromeric locations coincided with inversions found in Phaseoleae. Overall, this study provides a set of fundamental resources for cowpea improvement and enhances our understanding of cowpea subspecies divergence and genome evolution in Phaseoleae.

genomics↗

bioRxiv2025

Crosslinking of Lipid Nanoparticles Enhances the Delivery Efficiency and Efficacy of mRNA Vaccines

Lipid nanoparticles (LNPs) have enabled the effective delivery of RNA therapeutics and mRNA vaccines. However, their broader applications are limited by the suboptimal stability and endosomal escape efficiency. Here, we present an easy-to-adopt post-assembly crosslinking approach to enhance the structural and functional stability of mRNA LNPs. By leveraging a series of cholesterol derivatives and crosslinking methods, we induce crosslinks of the lipid components following mRNA LNP assembly to form the crosslinked LNPs (cLNPs). We systematically evaluated crosslinking parameters and identified optimal conditions that enhance both the physical stability and transfection efficiency of cLNPs. Our findings demonstrate that cLNPs exhibit improved structural integrity under storage and lyophilization conditions, as well as increased extracellular stability and endosomal escape efficiency, resulting in improved performance of mRNA LNPs both in vitro and in vivo. This crosslinking strategy represents a critical advance in LNP engineering, enabling more resilient LNPs and broadening the applicability of LNP-based therapies for gene therapy and vaccine delivery. Our work lays the foundation for developing next-generation LNPs with superior stability and delivery efficiency, broadening the impact of RNA therapeutics and vaccines.

bioengineering↗

bioRxiv2025

Spatial profiling reveals TREM2+ macrophages as central to Mycobacterium tuberculosis pathogenesis in human pulmonary tuberculosis

Pulmonary tuberculosis (TB) exhibits marked spatial heterogeneity, with alveolar pneumonia and organized granulomas frequently coexisting within the same lung. While granulomas have long dominated conceptual models of TB pathogenesis, the immune programs operating within alveolar TB pneumonia in humans remain incompletely defined. Here, we integrate spatial transcriptomics, single-cell RNA sequencing, high-resolution imaging, and functional assays of human lung biopsies to directly compare alveolar pneumonia with adjacent granulomas from the same individuals. We demonstrate that alveolar TB pneumonia is enriched for TREM2 lipid-laden macrophages characterized by lipid metabolic reprogramming, sparse T-cell infiltration, attenuated antimicrobial gene expression, and abundant Mycobacterium tuberculosis (Mtb) transcripts and antigens. In contrast, neighboring granulomas exhibit organized lymphoid architecture and robust antimicrobial programs. Mechanistically, the mycobacterial virulence lipid phthiocerol dimycocerosate (PDIM) and free mycolic acids induce TREM2 expression and activate TREM2-DAP12 signaling, promoting lipid droplet accumulation, suppressing autophagy, and enhancing intracellular Mtb survival in human macrophages. This immunometabolic state is pharmacologically reversible: 1,25-dihydroxyvitamin D downregulates TREM2, restores autophagy, reduces lipid droplets, and limits bacterial viability. Together, these findings define a spatially localized TREM2 foamy macrophage program within alveolar pneumonia that contrasts sharply with adjacent granulomatous immunity, establishing an niche permissive for bacillary persistence and potentially transmission, as well as identifying a tractable host pathway in human TB pathogenesis.

immunology↗

bioRxiv2025

Spatio-temporal mass spectrometry in living cells reveals regulators of cuproptosis

Cuproptosis is a unique form of regulated cell death triggered by excessive copper accumulation in mitochondria. To decipher the mechanisms of cuproptosis, we develop Spatio-Temporal Mass Spectrometry (STMS) technique to characterize dynamic subcellular proteomic changes during its early stage. STMS analysis reveals distinct subcellular proteome alterations and unique trafficking patterns over time. Through a genetic functional screen, we discover that copper stress reduces OXA1L in mitochondria, disrupting MRPL20 import and impairing oxidative phosphorylation complex I synthesis. This mitochondrial dysfunction promotes MRPL20 nuclear translocation, triggering the mitochondrial unfolded protein response as an adaptive mechanism to restore mitochondrial proteostasis during early cuproptosis. Meanwhile, AMPK phosphorylates ISCU at serine 29, stabilizing ISCU protein, and increasing the abundance of Fe-S cluster-containing proteins, which, in turn, enhances cells susceptible to cuproptosis. Building on this mechanistic insight, we develop AMPK-SPARK, a phase separation-based EGFP reporter for real-time visualization of endogenous AMPK activity in living cells during cuproptosis. Additionally, we identify COMMD4 as a cuproptosis sensor and establish a GFP-tagged COMMD4 cell model for high-content drug screening. Using this platform, we identify three FDA-approved drugs including Plerixafor, Dithranol, and Bleomycin as potential cuproptosis inhibitors. Overall, our work advances the understanding of cuproptosis regulation and provides valuable molecular tools and data resource for future research in this area.

cell biology↗

bioRxiv2025

Systemic trafficking of mRNA lipid nanoparticle vaccine following intramuscular injection generates potent tissue-specific T cell response

The mRNA lipid nanoparticles (LNPs) represent a new generation of vaccine carriers designed to elicit potent immune responses against infectious diseases and cancer. Despite the clinical success and rapid advancements in mRNA LNP technologies, the trafficking patterns of LNPs after intramuscular (i.m.) administration and the subsequent tissue-specific immunological effects have not been systematically characterized. Here, we report that trafficking of mRNA LNPs to different organs following i.m. injection is crucial for the induction of tissue-specific immunity beyond systemic immune response, particularly in tissue-resident CD8+ T cell generation, which is important for localized defense. By fine-tuning the composition of mRNA LNPs, trafficking patterns to systemic organs can be modulated, which can alter the resulting tissue-specific immune response. Formulations with a greater ability to enter the bloodstream can preferentially localize and transfect cells in specific organs like the liver, elicit stronger tissue-specific CD8+ T cell immune responses, and achieve enhanced efficacy in a liver tumor model. These findings highlight the potential to tailor mRNA LNP compositions to modulate trafficking following i.m. injection, thereby providing novel strategies for designing tissue-specific vaccines. Such strategies are particularly valuable for organ-specific diseases like cancer and infectious diseases, where tissue targeting and long-lasting immunity are essential for therapeutic success.

bioengineering↗

bioRxiv2025

In vivo genetic labeling of primary cilia in developing astrocytes.

Astrocyte cilia are largely understudied due to the lack of available tools. Astrocyte research advanced with the establishment of Aldh1l1-CreERT2, an inducible Cre line that specifically targets the astrocyte lineage. Here, we develop and compare genetic models that label astrocyte cilia in the developing prefrontal cortex (PFC) using Aldh1l1-CreERT2 and Cre-dependent cilia reporters. We evaluate these models by testing different tamoxifen-induction protocols and quantifying the percentage of astrocytes labeled with the cilia reporters. We show that tamoxifen dosage impacts the expression of cilia reporters in astrocytes. We validate the maximum cilia-labeling efficiency of tamoxifen using constitutively-expressed cilia reporters. The data reveal that only a subset of SOX9- positive astrocytes in the PFC possess cilia throughout development. Our work highlights the utility of Cre-Lox systems to target specific cell types and the importance of carefully validating genetic models.

neuroscience↗

bioRxiv2025

Calcium channel-coupled transcription factors facilitate direct nuclear signaling

VGCCs play crucial roles within the CNS, in maintaining cell excitability, enabling activity- dependent neuronal development, and forming long-term memory by regulating Ca2+ influx. The intracellular carboxyl-terminal domains of VGCC 1 subunits help regulate VGCC function. Emerging evidence suggests that some VGCC C-termini have functions independent of channel gating and exist as stable proteins. Here, we demonstrate that all VGCC gene family members express bicistronic mRNA transcripts that produce functionally distinct C-terminal proteins (CTPs) in tandem with full-length VGCC 1 subunits. Two of these CTPs, 1CCT and 1ACT, cycle to and from the nucleus in a Ca2+- and calmodulin-dependent fashion. 1CCT, 1ACT, and 1HCT regulate chromatin accessibility and/or bind directly to genes, regulating gene networks involved in neuronal differentiation and synaptic function in a Ca2+-dependent manner. This study elucidates a conserved process of coordinated protein expression within the VGCC family, coupling the channel function with VGCC C-terminal transcription factors.

neuroscience↗

bioRxiv2025

mRNA lipid nanoparticle-incorporated nanofiber-hydrogel composite generates a local immunostimulatory niche for cancer immunotherapy

Hydrogel materials have emerged as versatile platforms for various biomedical applications. Notably, the engineered nanofiber-hydrogel composite (NHC) has proven effective in mimicking the soft tissue extracellular matrix, facilitating substantial recruitment of host immune cells and the formation of a local immunostimulatory microenvironment. Leveraging this feature, here we report an mRNA lipid nanoparticle (LNP)-incorporated NHC microgel matrix, termed LiNx, by incorporating LNPs loaded with mRNA encoding tumour antigens. Harnessing the potent transfection efficiency of LNPs in antigen-presenting cells (APCs), LiNx demonstrates remarkable immune cell recruitment, antigen expression and presentation, and cellular interaction. These attributes collectively create an immunostimulating milieu and yield a potent immune response achievable with a single dose, comparable to the conventional three-dose LNP immunization regimen. Further investigations reveal that the LiNx not only generates heightened Th1 and Th2 responses but also elicits a distinctive Type 17 T helper cell-mediated response pivotal for bolstering antitumour efficacy. Our findings elucidate the mechanism underlying LiNxs role in potentiating antigen-specific immune responses, presenting a new strategy for cancer immunotherapy.

bioengineering↗

bioRxiv2024

Red-shifted GRAB acetylcholine sensors for multiplex imaging in vivo

The neurotransmitter acetylcholine (ACh) is essential in both the central and peripheral nervous systems. Recent studies highlight the significance of interactions between ACh and various neuromodulators in regulating complex behaviors. The ability to simultaneously image ACh and other neuromodulators can provide valuable information regarding the mechanisms underlying these behaviors. Here, we developed a series of red fluorescent G protein-coupled receptor activation-based (GRAB) ACh sensors, with a wide detection range and expanded spectral profile. The high-affinity sensor, rACh1h, reliably detects ACh release in various brain regions, including the nucleus accumbens, amygdala, hippocampus, and cortex. Moreover, rACh1h can be co-expressed with green fluorescent sensors in order to record ACh release together with other neurochemicals in various behavioral contexts using fiber photometry and two-photon imaging, with high spatiotemporal resolution. These new ACh sensors can therefore provide valuable new insights regarding the functional role of the cholinergic system under both physiological and pathological conditions.

neuroscience↗

bioRxiv2024

Dosage compensation of transposable elements in mammals

In mammals, X-linked dosage compensation involves two processes: X-chromosome inactivation (XCI) to balance X chromosome dosage between males and females, and hyperactivation of the remaining X chromosome (Xa-hyperactivation) to achieve X-autosome balance in both sexes. Studies of both processes have largely focused on coding genes and have not accounted for transposable elements (TEs) which comprise 50% of the X-chromosome, despite TEs being suspected to have numerous epigenetic functions. This oversight is due in part to the technical challenge of capturing repeat RNAs, bioinformatically aligning them, and determining allelic origin. To overcome these challenges, here we develop a new bioinformatic pipeline tailored to repetitive elements with capability for allelic discrimination. We then apply the pipeline to our recent So-Smart-Seq analysis of single embryos to comprehensively interrogate whether X-linked TEs are subject to either XCI or Xa-hyperactivation. With regards to XCI, we observe significant differences in TE silencing in parentally driven "imprinted" XCI versus zygotically driven "random" XCI. Chromosomal positioning and genetic background impact TE silencing. We also find that SINEs may influence 3D organization during XCI. In contrast, TEs do not undergo Xa-hyperactivation. Thus, while coding genes are subject to both forms of dosage compensation, TEs participate only in Xi silencing. Evolutionary and functional implications are discussed.

genetics↗

bioRxiv2024

Shroom3-Rock interaction and profibrotic function: Resolving mechanism of an intronic CKD risk allele.

Common intronic enhancer SNPs in Shroom3 associate with CKD in GWAS, although there is paucity of detailed mechanism. Previously, we reported a role for Shroom3 in mediating crosstalk between TGF{beta}1- & Wnt/Ctnnb1 pathways promoting renal fibrosis (TIF). However, beneficial roles for Shroom3 in proteinuria have also been reported suggesting pleiotropic effects. Here we focused on identifying the specific profibrotic Shroom3 motif. Given known therapeutic roles for Rho-kinase inhibitors in experimental CKD, and the established interaction between Shroom3 and Rock via its ASD2 domain, we hypothesized that Shroom3-mediated ROCK activation played a crucial role in its profibrotic function in high expressors. To test this hypothesis, we developed transgenic mice and cell lines that inducibly overexpressed wild-type- (WT-Sh3) or ASD2-domain deletion- Shroom3 (ASD2{Delta}-Sh3). Prior scRNAseq data showed that during TIF, Shroom3 and Rock co-expression occurred in injured tubular cells and fibroblasts, highlighting cell-types where this mechanism could be involved. Using HEK293T cells, we first confirmed absent ROCK binding and inhibited TGF{beta}1-signaling with ASD2{Delta}-Sh3-overexpression vs WT-Sh3. In mIMCD cells, ASD2{Delta}-Sh3 overexpression, reduced Rock activation (phospho-MYPT1), pro-fibrotic and pro-inflammatory transcripts vs WT-Sh3. Fibroblast proliferation (3T3) was also reduced with ASD2{Delta}-Sh3. In vivo, we studied ureteric obstruction (UUO) and Aristolochic nephropathy (AAN) as TIF models. In AAN, inducible global-, or Pan-tubular specific-, WTSh3-overexpression showed increased azotemia, and TIF vs ASD2{Delta}-Sh3 mice. WT-Sh3 mice consistently showed significant enrichment of Rho-GTPase, TGF{beta}1- and Wnt/CtnnB1- signaling in kidney transcriptome, paralleling Shroom3-coexpressed genes in tubulo-interstitial transcriptomes from human CKD. In UUO, again WT-Sh3 mice recapitulated increased fibrosis vs ASD2{Delta}-Sh3. Importantly, ASD2{Delta}-Sh3 did not develop albuminuria vs WT-Sh3, while mutating a disparate Fyn-binding Shroom3 motif induced albuminuria in mice, suggesting motif-specific roles for Shroom3 in the kidney. Hence, our data show a critical role for the Rock-binding, ASD2-domain in mediating TIF in milieu of Shroom3 excess, with relevance to human CKD.

systems biology↗

bioRxiv2024

easybio: an R Package for Single-Cell Annotation with CellMarker2.0

Single-cell RNA sequencing (scRNA-seq) allows researchers to study biological activities at the cellular level, enabling the discovery of new cell types and the analysis of intercellular interactions. However, annotating cell types in scRNA-seq data is a crucial and time-consuming process, with its quality significantly influencing downstream analyses. Accurate identification of potential cell types provides valuable insights for discovering new cell populations or identifying novel markers for known cells, which may be utilized in future research. While various methods exist for single-cell annotation, one of the most common approaches is to use known cell markers. The CellMarker2.0 database, a human-curated repository of cell markers extracted from published articles, is widely used for this purpose. However, it currently offers only a web-based tool for usage, which can be inconvenient when integrating with workflows like Seurat. To address this limitation, we introduce easybio, an R package designed to streamline single-cell annotation using the CellMarker2.0 database in conjunction with Seurat. easybio provides a suite of functions for querying the CellMarker2.0 database locally, offering insights into potential cell types for each cluster. In addition to single-cell annotation, the package also supports various bioinformatics workflows, including RNA-seq analysis, making it a versatile tool for transcriptomic research.

bioinformatics↗

bioRxiv2024

The neurotrophin artemin and its receptor GFRα3 mediate migraine-like pain via the ion channel TRPM8

BackgroundMigraine has a strong genetic foundation, including both monogenic and polygenic types. The former are rare, with most migraine considered polygenic, supported by genome-wide association studies (GWAS) identifying numerous genetic variants associated with migraine risk. Surprisingly, some of the most common mutations are associated with TRPM8, a non-selective cation channel that is the primary sensor of cold temperatures in primary afferent neurons of the somatosensory system. However, it is unlikely that the temperature sensitivity of TRPM8 underlies its role in migraine pathogenesis. To define the basis of the channels involvement, we reasoned that cellular processes that increase cold sensitivity in the skin, such as the neurotrophic factor artemin, via its receptor GFR3, also mediate TRPM8-associated migraine-like pain in the meninges. MethodsTo investigate the role of artemin and GFR3 in preclinical rodent migraine models, we infused nitroglycerin acutely and chronically, and measured changes in periorbital and hind paw mechanical sensitivity in male and female mice lacking GFR3, after neutralization of free artemin with specific monoclonal antibodies, or by systemic treatment with a TRPM8-specific antagonist. Further, in wildtypes and mice lacking either GFR3 or TRPM8, we tested the effects of supradural infusions of a mix of inflammatory mediators, artemin, and a TRPM8-specific agonist on migraine-related pain in mice. ResultsWe find that mechanical allodynia induced by systemic nitroglycerin, or supradural infusion of inflammatory mediators, involves GFR3. In addition, neutralization of circulating artemin reduces the nitroglycerin phenotype, demonstrating the importance of this neurotrophic pathway. Further, we show TRPM8 expression in the meninges and that direct supradural infusion of either a TRPM8-specific agonist or artemin itself produces mechanical allodynia, the latter dependent on TRPM8 and ameliorated by concurrent treatment with sumatriptan. ConclusionsThese results indicate that neuroinflammatory events in the meninges can produce migraine-like pain in mice via artemin and GFR3, likely acting upstream of TRPM8, providing a novel pathway that may contribute to migraine pathogenesis.

neuroscience↗

bioRxiv2024

Desmoplakin mutations in cardiac fibroblasts cause TGF?1-mediated pathological fibrogenesis in desmoplakin cardiomyopathy via beclin-1 regulation

BackgroundPathological fibrosis is a major finding in cardiovascular diseases and can result in arrhythmia and heart failure. Desmosome gene mutations can lead to arrhythmogenic cardiomyopathy (ACM). Among ACM, pathogenic desmoplakin (DSP) variants cause a distinctive cardiomyopathy with excessive cardiac fibrosis that could precede ventricular dysfunction. DSP variants are also linked to other fibrotic diseases. Whether DSP plays any role in pathological fibrosis remain unknown. MethodsMesenchymal stromal cells (MSCs) are resident fibroblast-like cells that are responsible for fibrogenesis in most organs, including hearts. We first used unbiased genome-wide analyses to generate cardiac fibroblasts-like, induced pluripotent stem cell-derived MSCs from normal donors and ACM patients with DSP mutations. We then studied the fibrogenic responses of cardiac MSCs to transforming growth factor beta-1 (TGF-{beta}1) using Western/Co-IP, autophagy assay, gene knockdowns/over-expressions, genomic analyses, mouse DSP knockdown models, immunostaining, and qPCR. ResultsTGF{beta}1 induced excessive accumulations of vimentin (VIM)/fibrillar collagens, and over-activated fibrotic genes in DSP-mutant MSCs when compared to normal MSCs. In normal MSCs, VIMs bind to wild-type DSP during normal fibrogenesis after TGF{beta}1. DSP-mutant MSCs exhibited a haplo-insufficient phenotype with increased DSP-unbound VIMs that sequestered beclin-1 (BECN1) from activating autophagy and caveolin-1 (CAV1)-mediated endocytosis. Decreased autophagy caused collagen accumulations and diminished CAV1 endocytosis resulted in abnormal CAV1 plaque formation that over-activated fibrotic genes [COL1A1, COL3A1, and fibronectin (FN)] via heightened p38 activities after TGF{beta}1. Genome-wide analysis and DSP knockdown in mouse fibroblasts confirmed this novel role of DSP mutations in pathological fibrosis. Overexpression of VIM-binding domains of DSP could suppress pathological fibrosis by increasing collagen autophagic degradation and decreasing fibrotic gene expressions. ConclusionsOur data reveal that DSP deficiency in MSCs/fibroblasts leads to exaggerated fibrogenesis in DSP-cardiomyopathy by decreasing BECN1 availability for autophagy and CAV1-endocytosis. Overexpression of VIM binding domains of DSP could be a new strategy to treat pathological fibrosis.

cell biology↗

bioRxiv2024

Esophageal epithelial Ikkβ deletion promotes eosinophilic esophagitis in experimental allergy mouse model

BackgroundEosinophilic esophagitis (EoE) is a chronic T helper type 2 (Th2)-associated inflammatory disorder triggered by food allergens, resulting in esophageal dysfunction through edema, fibrosis, and tissue remodeling. The role of epithelial remodeling in EoE pathogenesis is critical but not fully understood. ObjectiveTo investigate the role of epithelial IKK{beta}/NF{kappa}B signaling in EoE pathogenesis using a mouse model with conditional Ikk{beta} knockout in esophageal epithelial cells (Ikk{beta}EEC-KO). MethodsEoE was induced in Ikk{beta}EEC-KOmice through skin sensitization with MC903/Ovalbumin (OVA) followed by intraesophageal OVA challenge. Histological and transcriptional analyses were performed to assess EoE features. Single-cell RNA sequencing (scRNA-seq) was used to profile esophageal mucosal cell populations and gene expression changes. ResultsIkk{beta}EEC-KO/EoE mice exhibited hallmark EoE features, including eosinophil infiltration, intraepithelial eosinophils, microabscesses, basal cell hyperplasia, and lamina propria remodeling. RNA-seq revealed significant alterations in IKK{beta}/NF{kappa}B signaling pathways, with decreased expression of RELA and increased expression of IKK{beta} negative regulators. scRNA- seq analyses identified disrupted epithelial differentiation and barrier integrity, alongside increased type 2 immune responses and peptidase activity. ConclusionOur study demonstrates that loss of epithelial IKK{beta} signaling exacerbates EoE pathogenesis, highlighting the critical role of this pathway in maintaining epithelial homeostasis and preventing allergic inflammation. The Ikk{beta}EEC-KO/EoE mouse model closely mirrors human EoE, providing a valuable tool for investigating disease mechanisms and therapeutic targets. This model can facilitate the development of strategies to prevent chronic inflammation and tissue remodeling in EoE. Key MessagesO_LICritical Role of Epithelial IKK{beta}/NF{kappa}B Signaling: Loss of this signaling exacerbates EoE, causing eosinophil infiltration, basal cell hyperplasia, and tissue remodeling, highlighting its importance in esophageal health. C_LIO_LIMolecular Insights and Therapeutic Targets: scRNA-seq identified disrupted epithelial differentiation, barrier integrity, and enhanced type 2 immune responses, suggesting potential therapeutic targets for EoE. C_LIO_LIRelevance of the Ikk{beta}EEC-KO/EoE Mouse Model: This model replicates human EoE features, making it a valuable tool for studying EoE mechanisms and testing treatments, which can drive the development of effective therapies. C_LI Capsule SummaryThis study reveals the crucial role of epithelial IKK{beta}/NF{kappa}B signaling in EoE, providing insights into disease mechanisms and potential therapeutic targets, highly relevant for advancing clinical management of EoE.

immunology↗

bioRxiv2024

From gene to structure: Unraveling genomic dark matter in Ca. Accumulibacter

Candidatus Accumulibacter is a unique and pivotal genus of polyphosphate-accumulating organisms (PAOs) prevalent in wastewater treatment plants, and plays mainstay roles in the global phosphorus cycle. Whereas, the efforts toward a complete understanding of their genetic and metabolic characteristics are largely hindered by major limitations in existing sequence-based annotation methods, leaving more than half of their protein-encoding genes unannotated. To address the challenge, we developed a comprehensive approach integrating pangenome analysis, gene-based protein structure and function prediction, and metatranscriptomic analysis, extending beyond the constraints of sequence-centric methodologies. The application to Ca. Accumulibacter allowed the establishment of the pan-Ca. Accumulibacter proteome structure database, providing references for >200,000 proteins. Benchmarking on 28 Ca. Accumulibacter genomes showed major increases in the average annotation coverage from 51% to 83%. Genetic and metabolic characteristics that had eluded exploration via conventional methods were unraveled. For instance, the identification of a previously unknown phosphofructokinase gene suggests that all Ca. Accumulibacter encoded a complete Embden-Meyerhof-Parnas pathway. A previously defined homolog of phosphate-specific transport system accessory protein (PhoU) was actually an inorganic phosphate transport (Pit) accessory protein, regulating Pit instead of the high-affinity phosphate transport (Pst), a key to the emergence of the polyphosphate-accumulating trait of Ca. Accumulibacter. Additional lineage members were found encoding complete denitrification pathways. This study offers a readily usable and transferable tool for the establishment of high-coverage annotation reference databases for diverse cultured and uncultured bacteria, facilitating the exploration and understanding of genomic dark matter in the bacterial domain. SynopsisA integrated and advanced approach unraveling key genomic dark matter in Ca. Accumulibacter and readily applicable to diverse bacteria for customerized high-coverage annotation reference database establishment

genomics↗

bioRxiv2024

Multi-omics Reveals Immune Response and Metabolic Profiles during High-Altitude Mountaineering

The physiological perturbations induced by high-altitude exposure in mountain climbers, manifesting as metabolic and immunologic deviations, have been previously reported but are not fully understood. In this study, we obtained longitudinal multi-omic profiles of blood samples for healthy mountain climbers during two mountaineering stages (acclimatization and extreme altitude mountaineering). Our integrative assay included metabolomics and lipidomics profiling of plasma coupled with single-cell transcriptomic analysis of 375,722 immune cells. Longitudinal analysis revealed dynamic immune response profiles, during the acclimatization period, characterized by the downregulation of inflammatory responses in monocytes and classical dendritic cells (cDCs) and an increase in the proportion of cytotoxic CD8+ T cells with enhanced immune effector processes. In contrast, during extreme altitude mountaineering, the activation of inflammatory responses and impairment of T cell effector function were observed, concomitant with an increased cellular response to hypoxia and oxidative stress pathways. Furthermore, we found upregulated glycolysis and antioxidant gene expression during extreme altitude mountaineering, which was primarily orchestrated by HIF1A and NFE2L2, while decreased expression of these genes was observed in dysregulated plasmacytoid dendritic cells (pDCs). Finally, high-resolution plasma metabolic analysis revealed significant alterations in the metabolism of climbers, involving enhanced glutamine and fatty acid metabolism.

bioinformatics↗

bioRxiv2024

Plasticity and Dynamics of Hematopoietic Cells within Bone Marrow Microenvironment in Leukemia

Extensive research has been conducted on the plasticity of malignant cells and nonmalignant cells in solid tumor. However, the plasticity of bone marrow hematopoietic cells in leukemia have remained largely unexplored. In this study, we aimed to investigate cell changings in hematopoietic cells through lineage tracing across various types of leukemias. We had compiled a landscape of leukemia and constructed phylogenetic trees of hematopoietic cells through utilizing massively parallel scRNA-seq data, mtDNA mutation and SNP analysis. Based on the observed cell changings, we identified several types of cell changings, including transdifferentiation, dedifferentiation, and state transition, except for differentiation and expansion. In AML and CMML, GMPs and neutrophils showed a higher potential for transferring to other cell types. In BPDCN, pDCs were less prone to switching to other cell types, while T cells demonstrated high plasticity. In B-ALL and B-CLL, B-ALL blast cells and B-CLL blast cells emerged at the most dynamic state. The dynamics of hematopoietic cells in AML, BPDCN and ALL changed along with the clinical process. Extrinsic factors within the leukemia microenvironment may influence the cell changings. Regulons encountered an intermediate cell state during the process of transition to myeloid cells and erythroid cells. We also found a correlation between B-common blast cells and T cells, suggesting a potential transition from B lymphoblastic leukemia to T lymphoblastic leukemia. In conclusion, our study unveiled the distinct plasticity and dynamics of hematopoietic cells in various types of leukemia. This sheds light on the possibility of targeting cell changes as a new strategy for leukemia treatment and improving current immunotherapy.

bioinformatics↗