Biology subjects

Zhao, G.

Publications and source records attributed to Zhao, G..

At least 37 records · Page 2Linked to original sources

bioRxiv2025

Emergence and spread of outbreak-adapted Candidozyma auris harboring mutations in RBA1

Candidozyma auris is an emerging healthcare-associated fungal pathogen, increasingly isolated from clinical outbreaks, with a high propensity to colonize patients and the medical environment. Here, we leveraged C. auris isolates from multi-facility clinical outbreaks to identify genomic patho-adaptations promoting persistence and dissemination in the healthcare environment. Genomic and phylogenetic analyses revealed loss-of-function mutations in the uncharacterized C. auris transcription factor gene RBA1 to have independently emerged multiple times within these outbreaks. We demonstrate loss of RBA1 increases C. auris adhesion to plastic and human keratinocytes, enhances biofilm formation, and exacerbates fungal burden in a mouse model of catheter-associated urinary tract infection. Finally, we uncover mutations in RBA1 have emerged during multiple C. auris outbreaks across the globe, and that RBA1 mutant lineages are present among large ongoing clinical outbreaks. These results reveal loss-of-function mutations in C. auris RBA1 as a novel and clinically relevant genetic determinant of enhanced outbreak characteristics.

microbiology↗

bioRxiv2025

Antiphospholipid syndrome (APS) is a platelet factor 4 (PF4)-centric immunothrombotic disorder

Antiphospholipid syndrome (APS) is an immunothrombotic disorder, frequently attributed to autoantibodies that bind {beta}2-glycoprotein I ({beta}2GPI). A study showed that the platelet-specific chemokine, platelet factor 4 (PF4), binds to {beta}2GPI, enhancing recognition of {beta}2GPI by APS antibodies. APS antibodies induce the release of neutrophil extracellular traps (NETs), webs of decondensed chromatin that bind both PF4 and {beta}2GPI. We propose that PF4 bridges {beta}2GPI to NETs (and other PF4-targeted polyanions), leading to the formation of prothrombotic PF4:{beta}2GPI:NET immunotargets in APS. Dynamic light-scattering studies of isolated IgGs from four patients with triple-positive APS show formation of PF4:{beta}2GPI:NET complexes that bind APS antibodies. NETs released in a microfluidic system bound {beta}2GPI, but only in the presence of PF4, forming a multimolecular APS antigenic target. Whole blood infused through a photochemically-injured, endothelium-lined microfluidic channel formed platelet-, fibrin-, and complement-rich thrombi that bound APS antibody only in the presence of PF4. Thrombi were reduced in size if either ADAMTS13 or DNase1 was infused. In a murine APS model, wildtype and transgenic mice expressing platelet human PF4 {+/-} Fc{gamma}RIIA developed more intense neutrophil rolling along veins, and more extensive thrombus formation following laser injury to cremaster arterioles and venules, whereas mice lacking PF4 did not. Three antigenically distinct anti-hPF4 monoclonal antibodies blocked thrombosis in vitro, and neutrophil rolling and thrombosis in vivo. Our studies provide new insights into the basis of APS that has mechanistic parallels to other known PF4 immunothrombotic disorders and offer potential diagnostic and non-anticoagulant therapeutic strategies for clinical management. Key pointsO_LIPF4 enhances {beta}2GPI binding to NETs and these complexes are central to APS immunothrombosis. C_LIO_LIAnti-PF4 monoclonal antibodies block APS immunothrombosis in microfluidic and murine studies. C_LI

cell biology↗

bioRxiv2025

Core Activation Program and Selective Regional Responsiveness of Microglia in Aging and Parabiosis

Aging is associated with immune dysregulation in brain and is the biggest risk factor for many neurodegenerative diseases whereas rejuvenation interventions can mediate beneficial effects. Microglia are considered as a major player in the development of neurodegenerative disease yet, the molecular changes underlying brain aging and rejuvenation remain poorly understood at the single cell level. We identified and benchmarked several reproducible microglial states and a core set of genes leading to microglia activation in the mice brain. We investigated microglial heterogeneity and studied the impact of aging and parabiosis-mediated exposure of young and old blood on microglia subpopulations across four different brain regions including cerebellum, cortex, hippocampus, and striatum. We revealed region-specific differences in microglia subpopulation composition and age-related changes, with cerebellum and striatum displaying the most distinctive profiles and dynamic shifts compared to other brain regions. We consistently observed cerebellum as the most responsive, while striatum appeared distinctive by its minimal responsiveness to these interventions. Our findings highlighted the role of microglia in brain regional vulnerability and provided a foundation for microglia-targeted treatment for modulating brain aging. HighlightsO_LIDefined the composition of different microglial populations reproducible in aging and parabiosis, benchmarking a reference for the field. C_LIO_LIUncovered an under-appreciated core activation gene signature of microglia shared in all reactive states and regions during normal aging and old blood-induced aging. C_LIO_LIIdentified region-specific gene expression changes and associated biological processes in microglia during aging and parabiosis C_LIO_LIDiscovered microglial regional selectivity in response to aging and parabiosis, showing cerebellum as the most sensitive region and the striatum as the least affected. C_LI

neuroscience↗

bioRxiv2025

Neural Inflammation in Thoracic Dorsal Root Ganglia Mediates Cardiopulmonary Spinal Afferent Sensitization in Chronic Heart Failure

The cardiac sympathetic afferent reflex (CSAR) and pulmonary spinal afferent reflex (PSAR) amplify sympathetic outflow, and their sensitization contributes to chronic heart failure (CHF). Using a myocardial infarction (MI) rat model, molecular profiling, imaging, and functional assays revealed that thoracic dorsal root ganglia (DRGs) undergo marked macrophage and glial activation and suppression of voltage-gated potassium (Kv) channels after MI. In vitro studies confirmed that pro-inflammatory cytokines and activated macrophages directly reduce Kv channel expression and activity in DRG neurons. Cardiac afferents mediated cytokine transport from the heart to DRGs, driving macrophage infiltration in a cytokine receptor-dependent manner. Anti-inflammatory strategies including systemic minocycline, liposomal clodronate-induced macrophage depletion, or local epidural dexamethasone prodrug delivery reduced neuroinflammation, restored Kv channel levels, attenuated the exaggerated CSAR and PSAR, and improved cardiac remodeling. These findings highlight a cytokine uptake-driven inflammatory pathway in cardiopulmonary spinal afferent sensitization and support targeted DRG anti-inflammatory therapy as a potential cardioprotective approach. AbstractThe cardiac sympathetic afferent reflex (CSAR) and pulmonary spinal afferent reflex (PSAR) amplify sympathetic activity and may contribute to chronic heart failure (CHF). We hypothesized that neural inflammation in thoracic dorsal root ganglia (DRGs) drives cardiopulmonary afferent sensitization through suppression of voltage-gated potassium (Kv) channels after myocardial infarction (MI). MI was induced in rats by coronary ligation. Molecular profiling, immunofluorescence, tissue clearing, and functional assays were used to assess neuroinflammation and reflex responses. Post-MI, thoracic DRGs showed macrophage infiltration, glial activation, cytokine upregulation, and reduced Kv channel expression. Bulk RNA-seq identified enrichment of macrophage activation-related genes, and in vitro studies confirmed that pro-inflammatory cytokines and activated macrophages suppressed Kv channels and increased DRG neuron excitability. Epicardial injection of biotinylated TNF- demonstrated cardiac afferent-mediated cytokine transport to DRGs, inducing macrophage infiltration via a cytokine receptor-dependent mechanism. Anti-inflammatory interventions including oral minocycline, systemic macrophage depletion, and local epidural delivery of thermo-responsive hydrogel-forming dexamethasone prodrug (ProGel-Dex) significantly reduced DRG neuroinflammation, restored Kv channel levels, and attenuated exaggerated CSAR and PSAR responses. ProGel-Dex also improved cardiac chamber dilation in the post-MI rats. These findings identify a cytokine uptake-glial activation- macrophage activation pathway as a driver of cardiopulmonary afferent sensitization after MI. Targeting DRG inflammation, particularly with sustained local dexamethasone delivery using ProGel-Dex, offers a precision medicine to dampen pathological sympathetic activation and improve cardiac outcomes in CHF. HighlightsO_LIBoth cardiac (CSAR) and pulmonary (PSAR) spinal afferent reflexes are sensitized after myocardial infarction, contributing to sympathetic overactivation. C_LIO_LIThoracic dorsal root ganglia (T1-T4) exhibit macrophage activation, glial responses, pro- inflammatory cytokine upregulation, and suppression of Kv channels following MI. C_LIO_LICardiac afferents mediate receptor-dependent uptake and transport of cytokines (e.g., TNF-) from the heart to DRGs, driving macrophage infiltration and inflammation. C_LIO_LIActivated macrophages and pro-inflammatory cytokines reduce Kv channel expression and Kv current density (Ito) in DRG neurons, enhancing excitability. C_LIO_LIAnti-inflammatory strategies including minocycline, liposomal clodronate-induced macrophage depletion, and local epidural dexamethasone prodrug attenuate neuroinflammation, restore Kv channel expression, and suppress exaggerated CSAR/PSAR. C_LIO_LITargeting DRG inflammation, particularly via sustained epidural dexamethasone delivery, represents a promising cardioprotective precise medicine. C_LI

neuroscience↗

bioRxiv2025

Single nucleus multiomic atlas of human dorsal root ganglia reveals the contribution of non-neuronal cell types to pain

Sensory neurons residing in dorsal root ganglia (DRG) transmit sensory information such as pain, itch, touch, pressure and bodily position to the central nervous system. The activity of sensory neurons is regulated by non-neuronal cell types in the DRG, including satellite glial cells (SGCs), immune cells and fibroblasts. Dysregulated gene expression in DRG cells contributes to sensory nervous system disorders such as chronic pain. Understanding the genetic underpinnings of these conditions requires dissecting transcriptional regulation in human tissue. In this study, we profiled transcriptomic and chromatin accessibility landscapes from postmortem human DRG (hDRG) samples at single-nucleus level. We demonstrate that sequencing depth significantly impacts downstream analysis, with deeper sequencing yielding more detected cells and features, improved data integration, refined clustering and annotation, and more accurate scientific interpretations. We identified nine major cell types, defined their molecular signatures, and mapped cis-regulatory landscapes. Integration of gene expression with chromatin accessibility enabled peak-gene association and transcriptional network analyses, revealing transcription factors, their target genes, regulatory elements and potential partners that cooperatively drive cell-type-specific gene expression programs. This integrative approach identified cell types, genes, and cis-regulatory regions potentially driving pain conditions. Our unbiased genome-wide analysis not only recovered known pain-related genes but also highlighted novel candidate genes and regulatory regions implicated in pain mechanisms. Importantly, our results demonstrate that non-neuronal cells, including endothelial cells, fibroblasts, macrophages, and SGCs, play critical roles in pain pathogenesis and should be investigated as therapeutic targets. One Sentence SummaryOur work provides a comprehensive single-nucleus multi-omic atlas of human dorsal root ganglia, uncovering novel cell-type-specific regulatory mechanisms and candidate therapeutic targets for pain, thereby directly advancing translational insights into human sensory disorders and chronic pain pathogenesis.

neuroscience↗

bioRxiv2025

A multi-omic atlas of human autonomic and sensory ganglia implicates cell types in peripheral neuropathies

The human peripheral nervous system (PNS) consists of many ganglia including sympathetic ganglia (SG) and dorsal root ganglia (DRG). These ganglia house the cell bodies of diverse PNS neurons that transmit autonomic and sensory signals, as well as a much larger number of non-neuronal cells. However, the molecular and cellular diversity of these human PNS cell types and their implications in human disease remain elusive. By generating an integrated single-cell multi-omic atlas of human SG and DRG, we provide comprehensive transcriptional and epigenomic landscapes of various cell types in these peripheral ganglia. While the major cell types and their cell-type-specific transcriptional and epigenomic features are similar between human SG and DRG, we identify key differences between SG and DRG cell types. These differences highlight the distinct molecular and cellular mechanisms underlying their specific functions. We also profiled key genomic regulatory networks that govern cell-type-specific gene expression in these peripheral ganglia. Moreover, by mapping the expression and chromatin accessibility of disease-associated genes in human SG and DRG, we identify cell types that may underlie various peripheral neuropathies. This atlas serves as a valuable resource for understanding the intricate cell-type-specific molecules and interactions in the human PNS and their implications in human health and diseases.

neuroscience↗

bioRxiv2025

Structural and mechanistic insights into bacterial hydrazine biosynthesis

Nitrogen-nitrogen (N-N) bond-containing motifs are prevalent in both clinical drugs and natural products. Bacterial hydrazine synthetases catalyze N-N bond formation by coupling an amino acid and a hydroxylamine via a distinctive O-aminoacyl-hydroxylamine intermediate. Despite its wide occurrence, the structural and mechanistic basis of this process has remained elusive. Here, we report the first crystal structures of the O-aminoacyl-hydroxylamine synthetase component of a bacterial hydrazine synthetase, captured in binary and ternary complexes with substrates and catalytic intermediates. These structures reveal the molecular determinants of substrate recognition and, together with biochemical and computational analyses, establish a detailed mechanistic framework for the hydrazine synthetase family. Leveraging these insights, we expanded hydrazine biosynthesis through the targeted discovery of novel hydrazine synthetases and implemented a chemoenzymatic synthesis strategy. This work provides fundamental insights into hydrazine synthetases and lays the groundwork for their rational engineering as versatile biocatalysts.

microbiology↗

bioRxiv2025

Light-Activated Nucleic Acid Amplification Systems Using Photo-caged DNA Polymerase or Primers

Precise control over nucleic acid amplification is essential for achieving reliable, quantitative, high-throughput, and multiplexed molecular diagnostics, particularly in point-of-care and field settings. However, conventional isothermal amplification methods, especially rapid assays at ambient temperature such as recombinase-aided amplification (RAA), suffer from spontaneous initiation and lack of synchronization across parallel reactions. Here, we report light-activatable RAA systems employing two distinct photocaging strategies to achieve spatiotemporal control. In the first, a photocaged DNA polymerase was engineered via site-specific incorporation of p-azido-L-phenylalanine and conjugation with a 2-nitrobenzyl-modified ssDNA blocker through click chemistry. This approach offers high stability, making it advantageous for long-term storage and lyophilized formats. In the second, 5'-nitrobenzyl-modified primers were synthesized to block hybridization or extension until UV activation, offering operational simplicity and rapid integration into existing workflows. Both strategies independently suppressed background activity in the dark and restored full amplification efficiency upon 365 nm UV exposure. The systems exhibited high sensitivity, low background, and compatibility with portable diagnostics. A custom-built device integrating UV activation and real-time fluorescence detection enabled seamless, on-demand operation. This modular platform provides flexible light-gated amplification solutions, allowing the selection of polymerase- or primer-based caging according to storage stability or workflow requirements, thereby advancing precise and field-ready molecular diagnostics.

molecular biology↗

bioRxiv2025

Development of high-affinity, single-domain protein binders for neutralizing household allergens

Feline, canine, and human dust mite allergens drive significant IgE-mediated allergies in the household environment. Here, we describe the discovery and characterization of novel protein binders, termed AVA, which efficiently bind and disrupt major allergens from cats (Fel d 1), dogs (Can f 1, Can f 2), and dust mites (Der p 1, Der p 2). Leveraging camelid single-domain variable-heavy chain (VHH) antibodies, we identified and optimized VHH sequences with robust affinity towards the individual allergens. AVA disrupted critical allergen substructures (Fel d 1) and catalytic functions (Der p 1) in molecular dynamics simulations and in in vitro assays, respectively. Paired with robust thermostability and non-toxic in vitro viability profiles, AVA represents a promising approach for downstream household allergen mitigation.

bioengineering↗

bioRxiv2025

Precision culturomics enabled by unlabeled single-cell morphology and Raman spectra

Selective enrichment of target bacteria from complex communities such as the human microbiome has remained a challenge. Here we report a solution based on morphology, Raman spectrometry and the Laser-Induced Forward Transfer technology, which works at microbial single cells, many generations before they appear as colonies. We develop a machine learning-based framework that enables species-level targeted sorting of single microbial cells from complex microbiome. We illustrate the utility of this approach in selecting for or against specific bacteria in fecal microbiome samples and the potential for quantifying the molecules expressed based on Raman spectra. Analysis of single-cell cultured genomes reveals that brief antibiotic use drives both pre-existing resistance and de novo mutations in the transpeptidase or efflux pumps of gut commensals, along with convergent evolution between different species. Our precision culturomics method should enable detailed morphological, metabolic, and genomic insights into variations in microbial phenotypes at the single-cell level for microbiome studies.

microbiology↗

bioRxiv2025

Genome Mining and Characterization of a Heme-Dependent Enzyme Catalyzing Intermolecular Nitrogen-Nitrogen Bond Formation in Hydrazinosuccinic Acid Biosynthesis

Nitrogen-nitrogen (N-N) bond-forming enzymes are rare but play vital roles in both primary and secondary metabolism. Guided by a nitric oxide synthase (NOS)-based genome mining strategy, we report the discovery and characterization of a new heme-dependent enzyme system that catalyzes intermolecular N-N bond formation. Using both in vivo and in vitro reconstitution approaches, we demonstrated that a protein complex, comprising a heme enzyme and a 2[4Fe-4S] ferredoxin partner, mediates the coupling of the -amine group of L-aspartate with inorganic nitrogen oxide species, such as nitrite or nitric oxide, to generate hydrazinosuccinic acid, a key biosynthetic precursor in several natural product pathways. Structural modeling and site-directed mutagenesis suggest a plausible catalytic mechanism involving the formation of a reactive nitrogen intermediate, potentially a heme-bound nitrene species. These findings reveal a new family of N-N bond-forming biocatalysts that leverage inorganic nitrogen sources, offering valuable tools for genome mining and the synthetic biology.

biochemistry↗

bioRxiv2025

Mechanical force-mediated cellular crosstalk maintains the integrity of the lung gas exchange niche

Respiratory motion imposes a constant mechanical strain that has important but poorly defined impact on tissue niches in the lung. We developed a reversible bronchial ligation model to induce and reverse unilateral blockade of lung mechanical motion in vivo and show that this leads to transcriptomic changes in multiple cell lineages that are not normalized upon reinitiation of respiratory motion. Perturbation of mechanosignaling specifically in alveolar epithelial type I (AT1) cells alters the transcriptomic state and fate of their niche neighbors, demonstrating that AT1 cells act as a node that propagates a mechanical cascade throughout the lung alveolus. Mechanically perturbed AT1 cells induce a distinct capillary endothelial cell state that persists after reactivation of respiratory motion, which is mediated by an integrin/TGF-{beta} network within the alveolus that is vulnerable to pharmacological intervention. Importantly, AT1 mechanosignaling and intercellular communication are altered in chronic human lung diseases, highlighting the critical role of an AT1-driven mechanosensing network in lung disease biology. Thus, mechanosensing cells propagate biophysical signals that regulate tissue function and program tissue responses in disease.

cell biology↗

bioRxiv2025

The intratumoral microbiome is negatively associated with malignancy in dermatofibrosarcoma protuberans

In recent years, growing evidence demonstrated the critical roles of intratumoral microbes in tumors. However, the characteristics of intratumoral microbiome in dermatofibrosarcoma protuberans (DFSP) and their associations with tumor malignancy remains unexplored. Here, 106 whole-genome sequencing (WGS) data of the paired biopsy and blood samples from 53 DFSP patients were utilized, in which we extracted high-quality non-human reads to assign microbial taxonomic annotation by Kraken2 and PlusPF database. Meanwhile, significantly elevated non-human reads, microbial abundance, and bacterial load were detected in tumor compared to blood samples. To minimize the impact of contaminants and noise, we conducted a series of filtering procedures and treated blood samples as negative controls. Notably, we found that over 98% of intratumor microbes belonged to bacteria, and that the dominant taxa and alpha-diversity of intratumoral bacteria all exhibited significantly negative correlations with Ki67 expression in tumors. Specifically, the 84 key intratumoral species were identified to be associated with the reduced tumor malignancy, as evidenced by the diminished Ki67 expression, decreased tumor volume, and fewer COL1A1-PDGFB fusion events. These findings highlighted the tumor-suppressive potential of intratumoral microbiome, thereby providing a novel insight into DFSP pathogenesis and clinical management. IMPORTANCETo our knowledge, this is the first study to explore the intratumoral microbiome in DFSP. Microbial DNA signatures could be detected by whole-genome sequencing (WGS) and enabled a comprehensive view of the microbial landscape, thus we analyzed 106 WGS data of the paired biopsy and blood samples from 53 DFSP patients. Our analysis revealed that the dominant taxa and alpha-diversity of intratumoral microbiome all showed significantly negative correlations with Ki67 expression of tumor samples. This study indicated the tumor-suppressive role of intratumoral microbiome in DFSP and highlighted the potential clinical significance in understanding DFSP pathogenesis and guiding therapeutic management strategies.

microbiology↗

bioRxiv2025

Unveiling KRAS Mutant Structures with AlphaFold 3: New Avenues for Targeted Cancer Therapy

Despite recent advances in targeting the "undruggable" KRAS (Kirsten rat sarcoma viral oncogene homologue) protein, much of its structural information remains elusive. Utilizing a "branch-pruning" strategy, this study systematically mutated the Switch I and II regions of KRAS, predicting mutants structures with AlphaFold 3 and analyzing their structure differences with KRAS wildtype using PyMOL. The analysis of 494 mutants showed that over 64% had root-mean-square deviation (RMSD) scores below 0.200, indicating minor structural changes compared to wildtype KRAS. Notably, Switch II exhibited greater conformational variability, suggesting its potential role in oncogenic signaling. This work found that Q61 mutants showed limited structural changes, but nearby sites like E63 and M67 were more dynamic. Highly dynamic sites D38 (on Switch I) and E76/G60 (on Switch II) were identified, potentially affecting KRAS dimerization and post-translational modifications in oncogenesis. Mutants like D31I, R73C, and T74Q induced conformational changes, yet their biological functions are still unknown, possibly impacting effector binding and allosteric communication. These findings could reveal cryptic pockets for drug targeting, deepening our understanding of KRASs role in cancer.

cancer biology↗

bioRxiv2025

Evaluation of Alphafold modeling for elucidation of nanobody-peptide epitope interactions

Models of Ab-antigen complexes can be used to understand interaction mechanisms and for improving affinity. This study evaluates the use of the protein structure prediction algorithm AlphaFold (AF) for exploration of interactions between peptide epitope tags and the smallest functional antibody fragments, nanobodies (Nbs). Although past studies of AF for modeling antibody-target (antigen) interactions suggested modest algorithm performance, those were primarily focused on Ab-protein interactions, while the performance and utility of AF for Nb-peptide interactions, which are generally less complex due to smaller antigens, smaller binding domains, and fewer chains, is less clear. In this study we evaluated the performance of AF for predicting the structures of Nbs bound to experimentally validated, linear, short peptide epitopes (Nb-tag pairs). We expanded the pool of experimental data available for comparison through crystallization and structural determination of a previously reported Nb-tag complex (Nb127). Models of Nb-tag pair structures generated from AF were variable with respect to consistency with experimental data, with good performance in just over half (4 out of 6) of cases. Even among Nb-tag pairs successfully modeled in isolation, efforts to translate modeling to more complex contexts failed, suggesting an underappreciated role of the size and complexity of inputs in AF modeling success. Finally, the model of a Nb-tag pair with minimal previous characterization was used to guide the design of a peptide-electrophile conjugate that undergoes covalent crosslinking with Nb upon binding. These findings highlight the utility of minimized antibody and antigen structures to maximize insights from AF modeling.

biochemistry↗

bioRxiv2025

Structure-based analysis unveils co-origin of LPOR and nitrogenase-like proteins

Structures of nitrogenases, dark-operative protochlorophyllide oxidoreductases, and light-dependent protochlorophyllide oxidoreductases (LPOR) have been resolved. However, their evolutionary relatedness remains elusive. Here, we show, through structural alignment, that all subunits of nitrogenase-like proteins originated from a co-ancestral archaic one-subdomain precursor. LPOR evolved from the BchX/BchY subunits of nitrogenase-like chlorophyllide a oxidoreductase (COR), and the intermediary retinol dehydrogenase through possible genetic recombination. We thus establish previously unknown structural links among key enzymes involved in biological nitrogen-fixation (BNF) and photosynthesis, unraveling structure-guided functional evolution from a single-subunit iron protein to multi-subunit nitrogenase-like COR, and to the single-subunit LPOR for phototrophic metabolism via bacteriochlorophyll, retinal, and chlorophyll. This work also demonstrates structural similarities are imperative for inferring distant origins of functionally divergent proteins, particularly those lacking primary amino-acid sequence identity. Moreover, our findings coupled with AI may be exploited to design innovative light-driven CORs and/or light-utilizing nitrogenases with enhanced efficacy of photosynthesis and BNF. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=177 SRC="FIGDIR/small/634645v1_ufig1.gif" ALT="Figure 1"> View larger version (48K): org.highwire.dtl.DTLVardef@9f9a2aorg.highwire.dtl.DTLVardef@4243ecorg.highwire.dtl.DTLVardef@796b4corg.highwire.dtl.DTLVardef@17373da_HPS_FORMAT_FIGEXP M_FIG C_FIG Video abstracthttps://www.youtube.com/watch?v=b0qBE1JMaH0 HighlightsO_LILPOR evolves from BchX and BchY subunits of the nitrogenase-like protein (NGLP) COR C_LIO_LIAll subunits of NGLPs can be traced back to the ancestral one-subdomain precursor C_LIO_LIRetinol dehydrogenase acts as a crucial intermediate in the COR to LPOR evolution C_LIO_LIStructure-based design of LUN is showcased to revolutionize protein engineering C_LI

evolutionary biology↗

bioRxiv2025

Candida auris skin colonization is mediated by Als4112 and interactions with host extracellular matrix proteins

Candida auris is an often multidrug-resistant fungal pathogen notorious for persistent skin colonization and transmission in healthcare settings. However, the mechanisms driving its adherence to skin remain poorly understood. Here, we developed in vitro systems to allow for detailed analysis of early skin colonization events and identified critical host and pathogen mediators of attachment. Across multiple strains and clades of C. auris, we identified that Als4112, a conserved adhesin, is required for skin colonization via keratinocyte attachment and direct interactions with host extracellular matrix (ECM) proteins, especially basement membrane proteins such as laminin. In a murine epicutaneous infection and human skin explants, deletion of ALS4112 significantly reduced skin colonization, underscoring its essential role in establishing cutaneous persistence. Als4112 also contributes to systemic infection, highlighting the connection between adherence and pathogenicity in this organism. Finally, coating plastic and catheter surfaces with collagen I or III markedly inhibited C. auris attachment and biofilm formation, offering an approach to curb nosocomial transmission. Our study highlights the critical role of Als4112 in C. auris colonization and virulence in vivo, making it an attractive target for future vaccine development. This study also explores the potential of specific collagen coatings as a novel strategy to prevent C. auris adherence to abiotic surfaces, offering new therapeutic avenues to control the spread of C. auris in healthcare settings.

microbiology↗

bioRxiv2025

Peritoneal cavity-derived GATA6+ macrophages inhibit fibrosis through IL33 in endometrium

Macrophages exhibit a high degree of plasticity and play pivotal roles both in the normal physiological cycle of the endometrium and in its regeneration following injury. Although some new subsets of endometrial macrophages have been identified, their origins and functions remain to be further explored. In this study, we employed single-cell sequencing to analyze the endometrium of patients with normal endometrium and intrauterine adhesion (IUA) caused by injury. We identified a unique subset of macrophages distinguished by the expression of GATA6, a marker indicative of cavity macrophages. We verified that these GATA6+ macrophages were large peritoneal macrophages (LPMs) that migrated from the peritoneal cavity to the injured endometrium. Upon activation by injured endometrium, these LPMs demonstrated increased expression of Interleukin-33 (IL33), mediated by the Lars-Fos signaling axis, which interacts with the IL33 enhancer. Moreover, our studies revealed that IL33 derived from LPMs inhibited the differentiation of endometrial stromal cells (ESCs) into myofibroblasts, a critical step in the development of endometrial fibrosis. Furthermore, we confirmed the inhibitory effect occurred through the binding of IL33 to the ST2 receptor on ESCs, leading to the upregulation of JMJD3 and subsequent suppression of myofibroblast differentiation. Our findings highlight the essential role of LPMs in promoting endometrial repair and inhibiting fibrosis in IUA. Significance StatementThis study reveals the presence of a unique population of macrophages within the endometrium, originating from large peritoneal macrophages (LPMs), that are pivotal in endometrial repair. This finding offers new insights into the plasticity of macrophages and their potential therapeutic applications in treating endometrial fibrotic disorders.

immunology↗