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Sun, T.

Publications and source records attributed to Sun, T..

At least 19 recordsLinked to original sources

PlantOmicsGWAS: An end-to-end, reproducible framework for plant genome-wide association and genomic prediction using linear and pan-genome references

Genome-wide association studies (GWAS) play a crucial role in unraveling the genetic foundations of complex traits in plants but are also hampered by the application of heterogeneous tools, incompatible file formats and disparate computational environments. Existing GWAS frameworks are often restricted to a single linear reference genome, limiting the capacity for the analysis of structural variations and presence/absence variations (PAV) within plant populations. These issues pose obstacles to reproducibility, scalability, and comprehensive investigations. Here, we present PlantOmicsGWAS, an open-source Python framework for reproducible plant genome-wide association analysis and genomic prediction. It integrates reference indexing, FASTQ quality control, alignment, variant calling, VCF normalization, PLINK conversion, linkage disequilibrium analysis, population-structure estimation, association testing, marker scoring, genomic prediction, and visualization within a unified Linux and HPC workflow. The framework supports conventional linear-reference analyses and includes an optional pangenome-oriented module for working with multiple assemblies and graph-derived variation. Using a Vitis benchmark dataset containing 120 accessions and 118,247 graph-derived variants, PlantOmicsGWAS reduced manual workflow fragmentation and generated standardized association outputs. This tool provides a modular and extensible platform for plant GWAS and pan-GWAS workflows while retaining compatibility with established command-line tools and common genotype formats. The GWAS workflow described herein is adaptable to a range of sequencing methods and plant genomes, bridging research on crop related issues across various biological levels, from the individual organism to entire populations. PlantOmicsGWAS implements Bayesian sparse linear mixed modeling (BSLMM) through GEMMA for multi-trait association discovery, while also supporting FaST-LMM, regression-based approaches, and machine-learning algorithms (Random Forest, XGBoost) as benchmarking alternatives. The PlantOmicsGWAS, a versatile toolkit is available at GitHub https://github.com/plantomicsgwas1-boop/PlantOmicsGwas_V1 and on Linux and HPC platform (https://pypi.org/project/PlantOmicsGwas/1.0.2/).

bioinformatics↗

Community diversity and interaction of bacterial, cyanobacteria and protist among aquatic and soil micro-food chains

Microorganisms, found in every environment, play an important role in recycling matter and providing energy to the ecosystem. Here, we used 18S and 16S metabarcoding to study bacteria, cyanobacteria and protist community diversity and functional ecology among different environments of typical lake, river, marine and soil from the Yangtze Delta of China. The results showed that the similarity of cyanobacteria and protozoa communities in soil and aquatic environments was both higher than that of bacteria and microalgae communities. While the diversity of cyanobacteria and bacteria in lake was higher than that in river, marine and soil, the diversity of microalgae and protozoa in river was higher than that in lake, marine and soil. The {beta} diversity of cyanobacteria and bacteria marked differences in lake from other environments. But The distribution of dominant families of cyanobacteria, bacteria, microalgae and protozoa is similar to diversity. While significant positive correlations were found among dominant species of cyanobacteria, protozoa, bacteria and microalgae in lake the dominant species among bacteria, microalgae and protozoa in river, marine and soil all showed more negative correlations. Our study provides the basis for understanding the functional ecology of microbes in the micro-food webs of different environments.

ecology↗

Seasonal Rebalancing of Assembly Processes and Cross-Domain Network Restructuring in Microbial Communities of a Large Eutrophic Lake

Harmful algal bloom (HAB) succession in eutrophic lakes arises from seasonal rebalancing of selection, dispersal, and drift across interacting microbial domains, yet process attribution remains limited due to the scarcity of cross-domain analyses. Using multi-marker eDNA metabarcoding (16S rRNA, 18S rRNA, 23S rRNA), we show that bacterioplankton, cyanobacteria, phytoplankton, and zooplankton in Lake Taihu undergo coordinated spring-summer transitions, with inter-seasonal turnover far exceeding spatial heterogeneity. Assembly regimes shifted coherently across domains: spring communities were dominated by strong homogeneous selection--especially among cyanobacteria and microeukaryotes--whereas summer communities moved toward drift- or neutrality-like dynamics under bloom-stage mixing that enhanced dispersal. Null- and neutral-model diagnostics supported these trends. Cross-domain co-occurrence networks restructured seasonally, with summer networks becoming more connected and substantially more robust, indicating that bloom conditions foster cohesive, robust interaction structures rather than destabilization. These findings provide evidence that bloom progression restructures aquatic microbiomes through a seasonal rebalance of selection, drift, and dispersal coupled with adaptive strengthening of cross-domain connectivity, providing a process-explicit framework for understanding community stability and ecosystem resilience in eutrophic lakes.

ecology↗

Quantifying Cross-Modal Shared Information Between Histomorphology and Spatial Transcriptomics via Spatiotemporal Trajectory Correlation

Histopathological imaging and spatial transcriptomics (ST) provide synergistic morphological and molecular insights into tissue architecture. While conventional downstream analyses predominantly adopt a discrete paradigm, such as segmenting histological images or identifying spatial domains, emerging trajectory reconstruction methods offer a continuous perspective for analyzing these modalities. However, most current studies are confined to single-modality or single-organ analyses, lacking systematic integration across modalities and multiple organs. To address this limitation, we performed trajectory reconstruction on ST-derived gene expression data and on histopathological morphological features extracted using ten widely used pathology pretrained models across multiple cancer samples from six organs. The results demonstrate that trajectory reconstruction, as a continuous analytical framework, effectively bridges spatial transcriptomics and histopathological imaging. More importantly, we propose an innovative framework that uses trajectory pseudotime as a mediating variable to quantify the extent of information sharing between molecular and morphological features. This framework not only provides a new perspective for understanding the intrinsic links between modalities but also establishes a solid theoretical and methodological foundation for future cross-modal translation studies.

pathology↗

Temporal dynamics and functional divergence of the chloroplast division apparatus in Oryza sativa

O_LIChloroplast division is governed by a conserved protein machinery, yet empirical characterization of these regulators remains limited in rice, a primary target for C4 engineering. Increased chloroplast occupancy in bundle sheath cells is a hallmark of the C4 pathway and so manipulating division is a potential strategy to achieve this goal. C_LIO_LIThrough developmental transcript profiling and image analysis, we identified a discrete window of active chloroplast proliferation in rice leaves, coinciding with peak expression of conserved plastid division genes. Functional characterization via overexpression revealed regulatory behaviours distinct from those in Arabidopsis thaliana. Overexpression of OsFtsZ1&2 resulted in fewer, enlarged chloroplasts per bundle sheath cell, whereas OsMCD1&OsMinE restricted plastid expansion without altering division rates. Conversely, overexpressing OsPDV1&2 or OsARC6&OsDRP5B increased plastid size without affecting total count. When OsPDV1&2 were co-expressed with transcriptional regulator ZmG2, we observed modest increases in chloroplast size alongside reduced stomatal aperture, increased stomatal density, and higher intrinsic water-use efficiency. C_LIO_LIThe results define the temporal landscape of plastid biogenesis in rice and demonstrate divergence across lineages. Our findings suggest that manipulating the division apparatus is insufficient to drive C4-like chloroplast biogenesis in the rice bundle sheath, highlighting the complexity of plastid-host cell coordination in cereals. C_LI

Plant Biology↗

Fatty acid binding protein-8 (FABP8/PMP2) reveals molecular heterogeneity of myelin sheaths in the human CNS

Myelin is classically viewed as a uniform axon-insulating membrane, yet its molecular composition may differ between species and even within one species. Fatty acid binding protein-8 (FABP8/PMP2) was previously identified in CNS myelin of humans but not mice. Here we show that FABP8/PMP2 is a defining feature of CNS myelin in humans and old-world-monkeys, but absent from CNS myelin in other mammals, indicating evolutionary neofunctionalization of this lipid-binding protein in the primate lineage. In the human CNS, FABP8/PMP2 marks a subset of myelin sheaths that preferentially ensheath large-diameter axons, revealing sheath-to-sheath molecular heterogeneity correlated with axonal geometry. Chromatin is accessible at the PMP2/Pmp2 gene locus in oligodendrocytes of humans but not mice. Human oligodendrocytes intrinsically express FABP8/PMP2 when transplanted into mouse brains, demonstrating species-specific competence independent of environmental cues. Humanized transgenic mice expressing FABP8/PMP2 in oligodendrocytes form morphologically normal but developmentally transiently thicker myelin sheaths, and show elevated cholesterol content in purified myelin. Because FABP8/PMP2 binds cholesterol, we propose that its emergence in primate CNS myelin contributes to the cholesterol enrichment of human myelin. Thus, CNS myelin protein composition is evolvable and modular, with relevance for myelin lipids and morphology, and previously unrecognized complexity in neuron-glia co-adaptation. Main points- Fatty acid binding protein 8 (FABP8/PMP2) is present in CNS myelin of humans and old-world monkeys - PMP2 defines sheath-to-sheath heterogeneity in the human CNS - PMP2-immunopositive myelin ensheaths large-diameter axons - Human oligodendrocytes intrinsically express PMP2 upon transplantation into mice - Humanized PMP2-transgenic mice show thicker myelin and altered myelin lipid composition

neuroscience↗

Fibroblast TGF-β3 promotes tissue-residency and survival of CD8 T cells in barrier tissues and tumors

Fibroblasts are key organizers of tissue architecture and immune cell homeostasis, yet how they shape adaptive immune function within non-lymphoid tissues remains incompletely understood. CD8+ tissue-resident memory T cells (TRM) provide localized protection against pathogens and contribute to tumor control, but the microenvironmental signals that maintain their persistence and survival are poorly defined. Here, we identify fibroblast-derived TGF-{beta}3 as a conserved stromal niche factor that specifically sustains CD8+ TRM in both steady-state and disease settings. Across human single-cell cross-tissue atlases, CD8+ TRM preferentially correlated with fibroblast abundance in healthy barrier tissues and multiple tumor types, and TGFB3 emerged as a key fibroblast-enriched candidate mediator. In human and murine co-culture systems, fibroblast-derived TGF-{beta}3 promoted CD8 TRM-like differentiation in vitro. Using a novel genetic in vivo model, inducible fibroblast-specific deletion of Tgfb3 reduced CD8 TRM across barrier tissues at steady state and impaired antigen-specific CD8 TRM formation following viral infection. In tumor models, genetic loss or antibody mediated neutralization of TGF-{beta}3 impaired CD8 T cell residency and cytotoxicity, induced dysfunction via proteotoxic stress and apoptotic programs, and accelerated tumor growth. These findings provide mechanistic insight into the limited efficacy of pan-TGF-{beta} blockade in cancer therapy. Collectively, we describe a novel fibroblast-CD8 T cell axis mediated by TGF-{beta}3 that sustains residency and restrains proteotoxic stress in barrier tissues and tumors.

immunology↗

Sequence-Defined Digital Bottlebrush Polymers for Programmable Oligonucleotide Delivery

Oligonucleotide therapeutics hold transformative potential, yet their clinical translation is hindered by delivery barriers, including rapid renal/hepatic clearance and poor organ specificity. Bottlebrush polymers conjugates have emerged as a promising vector to address these limitations, but conventional architectures with uniform backbones can only achieve an unmodifiable, rigid biodistribution profile. Here, we report a library of sequence-defined "digital" bottlebrush polymers, precisely engineered with controlled placements of chemical motifs that modify physiochemical properties - including lipids, cholesterol, and cationic groups - along a polyphosphodiester backbone. Systematic evaluation of the digital bottlebrush polymer library reveals distinct structure-property relationships and enables organ-biased systemic delivery to several traditionally difficult-to-reach tissues, including muscle and skin. In a mouse model of rheumatoid arthritis, a single dose of a spleen-homing polymer-conjugated antisense oligonucleotide targeting TNF- achieves potent knockdown and drives full functional recovery. These findings establish a versatile design framework for tailoring bottlebrush polymers to specific therapeutic applications.

bioengineering↗

Identification of the Phytophthora PAMP Pep-13 Receptor Using Diploid Potato Inbred Lines

Plants employ cell surface receptors to recognize pathogen-associated molecular patterns (PAMPs) and activate pattern-triggered immunity, a crucial defense mechanism against invading pathogens. Pep-13 is a PAMP derived from a class of conserved cell wall transglutaminases present in Phytophthora species, and its receptor PERU (Pep-13 receptor unit), was reported recently. In our parallel study, we observed distinct responses to Pep-13 between two diploid potato inbred lines: E4-63 recognizes Pep-13, whereas A6-10 does not. Genetic analysis demonstrated that Pep-13 recognition in E4-63 is controlled by a single genetic locus, tentatively designated TGER (Transglutaminase elicitor response). Through bulked segregant analysis sequencing, followed by complementation assays, we found that the TGERa gene in E4-63 is essential for Pep-13 recognition. Sequence alignment revealed that TGERa shares 99.91% amino acid sequence identity with PERU, indicating that TGERa and PERU are allelic variants of the same gene (PERU/TGERa). TGERb, a highly homologous gene of TGERa, was identified in the E4-63 genome; notably, TGERa, but not TGERb, can recognize Pep-13. We further demonstrated that TGERb exhibits defects in ligand binding. Additionally, we found that the TGERa allele in A6-10 is a weak allele with reduced expression levels, presumably resulting from a 3 kb DNA fragment insertion in its first intron. Heterologous introduction of TGERa into Nicotiana benthamiana and tomato significantly enhanced their resistance to Phytophthora infestans. Collectively, our findings confirm that PERU/TGERa functions as the Pep-13 receptor in potato and provide a valuable molecular target for improving Phytophthora resistance in plants.

plant biology↗

KaroSpace: a rapid-access framework for interactive exploration of multi-sample spatial omics data

Spatial omics technologies enable high-resolution mapping of molecular and cellular organization within tissues, yet interactive exploration of these data remains challenging due to computational bottlenecks, and reliance on proprietary software infrastructures. We present KaroSpace, a framework for cell-centric exploration of multi-sample and multi-modality spatial omics data, agnostic to upstream analysis pipelines and operating on preprocessed spatial features. By combining a lightweight design with flexible deployment options, KaroSpace allows immediate interactive spatial data exploration, straightforward implementation to the broader scientific community, supports transparent data sharing, and complements existing computational workflows for hypothesis generation and collaborative analysis.

neuroscience↗

Salmonella exploits metal-responsive UMPylation to enable intracellular biphasic growth and antibiotic tolerance

Salmonella develops profound antibiotic tolerance during in vivo infection, directly contributing to antimicrobial treatment failure. Although phenotypic heterogeneity in bacterial growth rates underlies this tolerance, the exact mechanisms remain elusive. Here, we reveal that Salmonella exhibits a biphasic growth pattern within macrophages, with initial antibiotic levels modulating lag phase duration. Crucially, this growth plasticity is orchestrated by metal ion homeostasis and a reversible PTM-mediated protein phase transitions. Mechanistically, under stress conditions, enhanced Mn2+ uptake activates the UMPylator YdiU, which modifies critical translational machinery components such as elongation factor TufA. These modifications induce protein aggregation, leading to translational arrest and growth stasis. Conversely, upon stress alleviation, Salmonella accumulates Mg2+ and effluxes Mn2+, then the de-UMPylase YdiV is activated, which resolves protein aggregates to enable rapid bacterial resuscitation and proliferation. This metal-responsive proteostatic switch represents an evolutionarily conserved strategy for bacterial stress adaptation, with broad implications for combating antimicrobial tolerance. SIGNIFICANCE STATEMENTAntibiotic tolerance, a key cause of treatment failure in chronic infections, is often linked to bacterial phenotypic heterogeneity, yet the underlying regulatory mechanisms remain largely understood. This study uncovers a fundamental survival strategy employed by intracellular pathogen Salmonella, where host-derived manganese acts as a critical signal to induce a reversible, dormant state. We demonstrate that stress-induced Mn2+ influx activates widespread protein UMPylation, which functions as a molecular glue to drive the aggregation of essential proteins, thereby halting bacterial growth and conferring antibiotic tolerance. Crucially, this state is reversible upon stress relief through Mn2+ efflux and subsequent de-UMPylation, enabling rapid bacterial resuscitation. As an evolutionarily conserved mechanism of adaptive tolerance, this metal-ion-responsive switch, mediated by reversible protein UMPylation, identifies a key target for developing therapeutics against persistent bacterial infections.

microbiology↗

A Comprehensive Treatment-Induced Resistance Atlas of Glioblastoma Reveals a Fibrotic Niche Shielding the Tumor from Immunotherapy

Therapeutic resistance in IDH-wildtype glioblastoma (GBM) is driven by an intricate interplay between cellular plasticity and protective microenvironmental niches. By constructing the GRIT-Atlas--a massive transcriptomic compendium encompassing nearly one million high-quality single cells across 17 cohorts--and cross-analyzing it with 48 independent Visium spatial transcriptomics sections, we discover a recurrent "Spatial Resistance Triad" comprising mesenchymal-like (MES-like) malignant cells, myeloid-derived suppressor cells (MDSCs), and collagen-secreting cancer-associated fibroblasts (CAFs). This large-scale spatial integration reveals that the triad physically fortifies microvascular proliferation (MVP) and pseudopalisading necrosis (PAN) niches. To substantiate these findings at true single-cell resolution, we deploy high-plex spatial molecular imaging (CosMx SMI) to map over 400,000 single cells across a clinical validation cohort. This high-resolution architecture firmly validates the triads geography and, critically, provides structural gradient evidence unmasking a spatiotemporal continuum wherein PAN emerges as a direct functional consequence of MVP advancement and subsequent vascular collapse. Mechanistically, stromal CAF-derived COL6A1 engages CD44 receptors on MES-like cells to accelerate a potent neural stemness cascade within these protective domains. Utilizing a blood-brain barrier (BBB)-penetrant multi-library compound screen, we identify Lacidipine as a multi-modal stromal disruptor that successfully silences CAF activation and halts matrix secretion. Incorporating Lacidipine into the standard chemo-immunotherapy backbone (TMZ + anti-CSF1R) completely dismantles the protective desmoplastic matrix niche, forcing a profound collapse of intracranial tumor burden and dramatically extending overall survival in orthotopic models. Collectively, our study leverages unprecedented single-cell and spatial scale to provide a definitive blueprint of GBM therapeutic evasion, establishing matrix-targeted intervention as a mandatory prerequisite for successful glioblastoma eradication.

cancer biology↗

Combined antagonism of Oncostatin M (OSM) and Interleukin 6 (IL-6) provides both anti-fibrotic and anti-inflammatory benefit in pulmonary fibrosis

Interstitial lung diseases (ILDs), including idiopathic pulmonary fibrosis (IPF) and systemic sclerosis-associated ILD (SSc-ILD), are irreversible fibrosing diseases with a mean survival time of less than 5 years for IPF. Poorly understood etiology and complex pathogenesis of these diseases have hampered the identification and development of effective therapeutics. Existing treatments can slow progressive fibrosis and lung function decline but do not stop it entirely, resulting in a minimal impact on patient survival. Thus, novel therapeutic interventions are needed. Tocilizumab, an anti-IL-6 receptor antibody, was recently approved by FDA for the treatment of SSc-ILD based on evidence demonstrating a reduction in the rate of lung function decline. In this study, we have characterized an IL-6-driven feed-forward myeloid axis contributing to lung inflammation providing a mechanistic hypothesis for tocilizumab. Concomitantly we have identified an oncostatin M (OSM) orchestrated lung injury response contributing to epithelial and endothelial cell disruption, myofibroblast activation and fibrosis. Despite dysregulated expression of IL11 in IPF, SSc-ILD, and murine models of fibrosis, we found no evidence for a pro-fibrotic role for IL-11 in vitro or in vivo. Instead, in pre-clinical models of IPF we demonstrate that antagonism of OSM alone, or to a greater degree in combination with IL-6, reduced lung fibrosis and inflammation. Translating these observations, we validated gp130:OSMR, rather than gp130:LIFR, as the dominant human receptor complex used by OSM, identifying OSMR as a potential therapeutic target to stall fibrosis.

immunology↗

Mechanisms of soil carbon preservation illuminated by model mineral-associated organic matter

A central control on atmospheric CO2 is the stabilization of organic carbon in soils. While there are well-described properties associated with stable soil carbon, such as interactions with minerals and conserved chemical features, determining the mechanisms underlying these properties is challenged by soil complexity and heterogeneity. Here we synthesize a naturally complex, tunable model form of mineral-associated organic matter (LabMAOM) to explore mechanisms of stable soil carbon formation and persistence. We show that mineral association and ambient organic matter synergistically stabilize LabMAOM against microbial decomposition. Moreover, different starting compositions of organic matter yield a conserved final LabMAOM chemical composition consistent with natural soils. Our findings open new mechanistic understanding of stable soil carbon and will be of utility to climate modeling and soil health management.

synthetic biology↗

Liver Zonation Disruption Fuels Hepatocellular Carcinoma in Chronic Liver Disease

Hepatocellular carcinoma (HCC) arises almost exclusively in chronic liver disease (CLD), yet the classical etiological drivers of injury insufficiently explain why only a subset of patients progress to cancer. Here, we identify disruption of liver metabolic zonation, specifically, aberrant expansion of {beta}-catenin activity from pericentral to periportal territories as a previously unrecognized tumorigenic risk state that emerges across etiologically diverse CLDs. Using spatial transcriptomics and immunohistochemistry from murine liver disease followed by human sample validation, we demonstrate that MASLD/MASH, alcohol-associated hepatitis, viral hepatitis, and immune-mediated cholangiopathies share a striking periportal induction of pericentral {beta}-catenin target programs, indicating a conserved zonation disturbance independent of disease etiology. Since {beta}-catenin expansion occurs alongside inflammation, fibrosis, and metabolic dysfunction in human CLD, its direct oncogenic contribution remained unclear. To functionally isolate the tumorigenic consequence of zonation disruption itself from these confounding disease processes, we employed hepatocyte-specific deletion of ZNRF3 and RNF43--negative regulators that physiologically restrict {beta}-catenin to the pericentral zone. Lineage tracing demonstrates that ZNRF3/RNF43 deletion drives selective periportal hepatocyte proliferation, zonal reprogramming, and tumor initiation in a {beta}-catenin-dependent manner, establishing zonation disruption as a direct mechanistic driver of carcinogenesis. The resulting tumors exhibit a distinct metabolic and immunologic phenotype, including heightened mitochondrial respiration, preserved periportal identity, and T-cell competence, and correspond to a molecularly defined subset comprising 5-10% of human HCCs. Together, these findings reveal {beta}-catenin zonation expansion as a conserved and previously unrecognized HCC risk factor that mechanistically links chronic liver injury to malignant transformation. They further establish ZNRF3/RNF43 deletion as a tractable model of zonation-driven hepatocarcinogenesis and identify a distinct human HCC subtype with unique therapeutic vulnerabilities, opening new avenues for mechanism-based risk stratification, early detection and preventive therapeutic strategies in patients with chronic liver disease.

cancer biology↗

Anoctamin-2-specific T Cells Link Epstein-Barr Virus to Multiple Sclerosis

Multiple sclerosis (MS) occurs when the central nervous system (CNS) is damaged by misguided adaptive immune responses, likely caused by a combination of environmental factors in genetically susceptible individuals. A known prerequisite for disease is Epstein-Barr virus (EBV) infection, and previous studies have demonstrated elevated Epstein-Barr virus nuclear antigen 1 (EBNA1) antibodies which cross-react with the calcium-activated chloride channel anoctamin-2 (ANO2) in persons with MS (pwMS). ANO2-reactive antibodies have been associated with greater neuroaxonal damage in MS, although their exact effector function is still uncertain. Here, we demonstrate that ANO2 is also the target of IFN{gamma}-producing CD4+ T cells, which are more frequent in untreated and natalizumab-treated pwMS compared to control individuals. Immunisation of SJL/J mice with either ANO2 or EBNA1 elicited cross-reactive CD4+ T cell and antibody responses in vivo. Pre-immunisation of young mice with ANO2 worsened proteolipid protein (PLP)-induced experimental autoimmune encephalomyelitis (EAE), which in older mice included atypical clinical phenotype, immune infiltration into the brain and reduced survival. EAE exacerbation was recapitulated with the adoptive co-transfer of ANO2 and myelin antigen-specific CD4+ T cells, and ANO2-specific T cells alone could induce the cell death of ANO2-expressing glial cells in vitro. T cell clones with cross-reactivity to both EBNA1 and ANO2 antigens could be isolated from natalizumab-treated pwMS. Single cell sequencing of EBNA1 and ANO2-specific T cell receptors (TCR) from four pwMS revealed a significant overlap between their antigen-specific expanded TCR repertoires within donors and transcriptomic analysis showed cross-reactive T cells to have predominantly activated and cytotoxic phenotypes. In summary, we report the first mechanistic evidence that EBNA1 CD4+ T cells can target the MS-associated autoantigen ANO2, thereby establishing a link between EBV infection and development of autoimmune neuroinflammatory disease.

immunology↗

Synthetic Modular Cyanobacterial Consortium Enables Carbon-Negative Production of Glycerol and Derivatives

Cyanobacteria offer a direct route for converting solar energy and CO2 into valuable chemicals, yet the metabolic burden of complex heterologous pathways often limits their productivity and stability. Here, we present a modular co-culture strategy that uses glycerol as an efficient mediator metabolite to link cyanobacterial carbon fixation with downstream bioconversion. We first engineered Synechococcus elongatus UTEX 2973 (Syn2973) for high-level glycerol biosynthesis by optimizing synthase selection, eliminating competing pathways, and improving CO2-supply conditions, achieving a production of 14.53 g{middle dot}L-1. In parallel, we constructed glycerol conversion modules in Syn2973 and Gluconobacter oxydans enabling production of 1,3-propanediol (1,3-PDO), 3-hydroxypropionic acid, and dihydroxyacetone, with exogenous glycerol yielding up to 30.07 g{middle dot}L-1 1,3-PDO. Integrating the two modules resulted in a fully autotrophic co-culture that produced all three target chemicals directly from CO2, including semi-continuous 1,3-PDO production at 6.02 g{middle dot}L-1{middle dot}day-1, corresponding to a net carbon fixation efficiency of 3.43 kg CO2 eq/kg 1,3-PDO.

synthetic biology↗

Oligodendroglia as functional effectors of Multiple Sclerosis risk variants

Multiple sclerosis (MS) is a neuroinflammatory disease for which a large number of non-coding single nucleotide polymorphisms (SNPs) have been associated with disease risk/susceptibility. Immune cells have been suggested as the principal functional effector cell types of these common variants. Here, we identify 76 MS-associated SNPs whose loci present accessible chromatin in homeostatic and diseased oligodendroglia (OLG), including both oligodendrocyte precursor cells (OPCs) and mature oligodendrocytes (MOLs). By applying high-throughput functional genomics, we found that a subset of these SNPs led to variant- and cell-specific regulatory effects in human induced pluripotent stem cell-derived oligodendroglia. Phenotypic profiling of these variants indicated that rs483180:PHGDH interfered with human OPC proliferation via long-range chromatin interactions with the S100A6 locus, while variants at rs2248137:CYP24A1 impaired oligodendrocyte differentiation by regulating BCAS1 expression. In addition, variants at rs1415069:DIPK1A enhanced secretion of the cytokine CCL2 by oligodendroglia, suggesting that these variants might be implicated in OLG-driven immune cell recruitment in MS. These findings position oligodendroglia as important drivers of MS pathogenesis through modulation of both their cell-intrinsic oligodendroglial function and intercellular communication by non-coding MS risk variants.

cell biology↗