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Biology subjects

Yuan, M.

Publications and source records attributed to Yuan, M..

At least 19 recordsLinked to original sources

Protective pan-betacoronavirus neutralizing antibodies by vaccination

The continued emergence of betacoronaviruses underscores the urgent need for vaccines that provide broadly protective immunity. Here, we present an epitope-focused vaccine strategy targeting the conserved S2 stem-helix region of the spike fusion machinery, a broadly neutralizing antibody-(bnAb) epitope shared across betacoronaviruses yet partially occluded on the native spike. Immunization of non-human primates with engineered S2 stem-helix nanoparticle immunogens, alone or followed by a SARS-CoV-2 BA.1 spike mRNA boost, elicited broadly cross-reactive antibody responses against sarbecoviruses, merbecoviruses, and embecoviruses and neutralized SARS-CoV-2, multiple variants, other sarbecoviruses, and MERS-CoV. Vaccine-elicited monoclonal antibodies displayed broad in-vitro neutralizing activity and protected against both SARS-CoV-2 and MERS-CoV in-vivo. Structural analyses revealed conserved features between rhesus and human stem-helix bnAbs, supporting the translational potential. Overall, our findings provide proof-of-concept that epitope-focused nanoparticle immunogens can target partially occluded, immunoquiescent bnAb epitopes, laying the groundwork for pan-betacoronavirus vaccines that provide broad protection and strengthen pandemic preparedness. ONE SENTENCE SUMMARYEpitope-focused S2 stem-helix nanoparticle immunogens elicit protective broadly neutralizing antibodies (bnAbs) against diverse betacoronaviruses in non-human primates, establishing a framework for development of pan-betacoronavirus vaccines.

immunology↗

Group size and activity influence shoal choice in Goldfish: Replication of zebrafish findings using a drift-diffusion model

Animals often rely on social information when making movement decisions. In zebrafish, classic work showed that shoal size and shoal activity both bias shoal choice. Here we extend these effects in Goldfish (Carassius auratus) and extend them with a drift-diffusion model (DDM) account of individual evidence accumulation under dynamic social cues. Using a three-chamber linear arena, we quantified a focal fishs position for 10 minutes while manipulating (i) numerical differences between flanking shoals and (ii) their activity (swimming speed) via temperature manipulation. ANOVA on time-proportion choices confirmed robust attraction to larger shoals; when shoal sizes were equal, the more active shoal was preferred. In combined manipulations, activity effects dominated at small numbers but saturated as group size increased, indicating a threshold-like integration where activity dominates at small shoal sizes (<3 fish) but saturates at larger sizes. We formalize these processes with a bounded DDM in which a sigmoidal stimulus function maps shoal size and average speed to momentary evidence, subject to random perturbations. The model reproduces the observed psychometric relations between relative numerosity, velocity differences, and choice. Our results (i) generalize zebrafish findings to a carp species with distinct ecology and physiology, and (ii) provide a compact mechanistic link between social cues and individual decision trajectories in dynamic social contexts.

animal behavior and cognition↗

Improving Variant Effect Prediction by Steering Sparse Mechanistic Features in Protein Language Models

Protein language models (PLMs) like the ESM series encapsulate immense evolutionary knowledge within their high-dimensional continuous embeddings. However, these latent representations are densely entangled, obscuring the fine-grained biophysical constraints necessary for precise functional resolution. To unlock the full expressive power of these embeddings, we propose PLM-SAE, a mechanistic framework that employs Sparse Autoencoders (SAEs) to disentangle PLM representations into discrete, biologically interpretable activations. By isolating and directly intervening on critical functional features, we fundamentally enhance the structural and mutational awareness of the underlying embeddings. We rigorously validate this embedding enhancement on variant effect prediction (VEP). In the unsupervised zero-shot setting, our sparse modulation elevates the state-of-the-art ESM-3 model, yielding performance improvements across 114 deep mutational scanning datasets and delivering an 80.8% relative improvement on challenging targets like the human E3 ubiquitin ligase HECD1. Furthermore, our target-specific differentiable gating mechanism achieves consistent performance gains in over 80% of evaluated datasets with an average Spearman{rho} increase of +0.138. Finally, extending this approach to a cross-fitness multitask architecture establishes new state-of-the-art results on 17 VenusMutHub datasets, highlighted by a 169.0% performance surge in small-molecule binding predictions. Our work demonstrates that refining the highly entangled latent manifold via sparse modulation provides a robust and generalizable foundation for enhancing downstream PLM capabilities.

bioinformatics↗

Somatic evolution of a cross-reactive germline antibody that expands its breadth to neutralize new SARS-CoV-2 variants

Rapid antigenic drift of the SARS-CoV-2 receptor-binding domain (RBD) underlies immune escape and continues to challenge the durability of antibody-mediated protection. Among the major classes of RBD-directed antibodies, germline-encoded IGHV3-53 responses are highly potent against early SARS-CoV-2 variants but are generally compromised by Omicron-associated mutations. Here, we identify an intrinsically cross-reactive IGHV3-53 germline antibody that recognizes multiple pre-Omicron variants, including SARS-CoV-2 wild-type, Alpha, and Delta. Notably, we demonstrate that targeted somatic evolution can further expand this breadth to overcome the immune escape of different Omicron variants. Guided by integrated structural and sequence analyses, we introduce four somatic mutations (G26E, T28I, S53P, and Y58F) into the germline antibody, resulting in markedly enhanced binding and neutralization of Omicron BA.1, BA.2, and BA.4/5. High-resolution crystal structures reveal that these mutations re-establish critical interactions disrupted by substitutions on Omicron RBD and optimize affinity at a remodeled epitope interface. Collectively, our findings delineate a structural and mechanistic pathway through which an inherently cross-reactive germline antibody lineage can be adaptively refined to counter highly divergent SARS-CoV-2 variants. This work highlights the underappreciated breadth encoded within the naive B-cell repertoire and provides a conceptual framework for engineering and eliciting antibody responses resilient to future antigenic drift.

immunology↗

Integrated single-cell and spatial transcriptomic analysis of T cell exhaustion and immunometabolic remodeling in HPV-positive oropharyngeal squamous cell carcinoma

HPV-positive oropharyngeal squamous cell carcinoma (OPSCC) harbors dense lymphocytic infiltration yet responds poorly to immune checkpoint blockade (ICB), a paradox whose mechanistic basis remains unresolved. Here we constructed an integrated single-cell and spatial transcriptomic atlas of HPV OPSCC (23,119 cells, 24 cell types), complemented by CRISPR-Cas9 functional validation in two HPV cell lines and multiplex immunofluorescence across independent cases. Pseudotime trajectory analysis placed TOXCD8 T cells, rather than canonically defined exhausted cells, at the terminal exhaustion endpoint, and uncovered a previously uncharacterized IEGCD8 effector memory population at a fate-decision juncture between activation and irreversible exhaustion. Actively cycling Tregs with broad co-stimulatory and co-inhibitory receptor expression underwent intratumoral immunosuppressive differentiation. Compartmentalized LDHA/MCT4 expression in cancer cells versus LDHB/MCT1 in T cells established a directional lactate flux model, and spatial deconvolution confirmed peripheral immune exclusion. We identified a KMT2D-KLF7-PD-L1 regulatory axis: KMT2D sustains KLF7 transcription through H3K4me1-dependent enhancer activation; KLF7 concurrently drives neural crest differentiation and upregulates PD-L1, thereby linking epigenetic remodeling to both neural programming and immune checkpoint expression. These findings define converging multi-scale mechanisms underlying ICB resistance in HPV OPSCC and nominate the KMT2D-KLF7-PD-L1 axis as a combinatorial therapeutic target.

cancer biology↗

GCN-Mamba: Graph Convolutional Network with Mamba for Antibacterial Synergy Prediction

The escalating crisis of antimicrobial resistance necessitates novel therapeutic strategies, among which drug combination therapy shows great promise by enhancing efficacy and reducing toxicity. However, identifying effective synergistic pairs from the vast combinatorial space remains experimentally challenging and resource-intensive. To address this, we introduce GCN-Mamba, a deep learning framework that integrates Graph Convolutional Networks (GCN) with the Mamba State Space Model. This architecture captures both local molecular topological structures and global implicit interactions by leveraging Extended 3-Dimensional Fingerprints (E3FP) and bacterial gene expression profiles. Evaluation on a comprehensive dataset demonstrated that GCN-Mamba significantly outperforms classical machine learning models in predictive accuracy. In a targeted case study against Methicillin-resistant Staphylococcus aureus (MRSA), the model successfully rediscovered known synergistic pairs, such as Quercetin and Curcumin, consistent with recent literature. Furthermore, prospective in vitro validation confirmed a novel synergistic combination of Shikimic acid and Oxacillin, validating the models practical utility. By efficiently prioritizing potential candidates, GCN-Mamba serves as a powerful and reliable tool for accelerating the discovery of synergistic antimicrobial combinations, effectively bridging the gap between computational prediction and experimental validation.

bioinformatics↗

Global climate gradients structure soil Legionella diversity, relative abundance and pathogen distributions

Legionnaires disease has increased sixfold since 2000 in the United States, yet environmental reservoirs such as soils remain understudied sources of infection. It remains unclear how the diversity and abundance of environmental pathogens, such as Legionella, will shift as the climate continues to change. Here, we utilize 4,287 publicly available global soil 16S rRNA gene amplicon datasets to analyze how the distribution of the genus Legionella, including pathogenic lineages, varies across continental-scale biogeographic regions and along climatic and geochemical gradients. Legionella relative abundance increased across the joint precipitation-air temperature gradient, and mixed-effects modeling indicated that the chance of detecting Legionella in soils increased substantially when annual precipitation reached [~]500 mm. Legionella diversity was characterized by high spatial turnover, with the majority of abundant ASVs restricted to individual regions despite broad phylogenetic representation across the genus. Further, fewer than 2% of our 16S-derived Legionella sequences matched ASVs corresponding to characterized species, and the clinically dominant species L. pneumophila was rarely detected. In contrast, ASVs matching several other known pathogens (L. longbeachae, L. anisa, L. bozemanae, L. cincinnatiensis) were orders of magnitude more common than L. pneumophila in soils. Moreover, pathogenic Legionella ASVs were detected significantly more frequently at warmer and wetter conditions. Collectively, our findings suggest that Legionella relative abundance and diversity in soils, especially pathogenic lineages, are shaped by both dispersal and climatic filtering. As temperature and precipitation regimes shift in the future, our results imply that soils should be an important pathogen source to monitor and that Legionella species beyond L. pneumophila warrant increased ecological and public health attention.

microbiology↗

Multiscale confidence quantification for virtual spatial transcriptomics with UTOPIA

Virtual spatial transcriptomics (ST) methods predict gene expression or cell types from histology images, extending molecular readouts beyond the limited regions or samples directly measured by ST platforms. However, the statistical reliability of these predictions remains unclear. Here, we present UTOPIA, a model-agnostic framework for multiscale confidence quantification in virtual ST. UTOPIA assigns statistically calibrated confidence scores to predictions across spatial resolutions and biological granularities, ranging from single genes to metagenes and from specific cell types to broader cell classes. UTOPIA controls false discovery rates for detecting genes, metagenes, or cell types while accounting for local tissue context. We show that prediction confidence depends critically on both spatial resolution and biological granularity, with reliable inference often emerging only at coarser, biologically meaningful scales. Across multiple ST platforms and in both in-sample and out-of-sample settings, UTOPIA enhances interpretability, prevents false biological conclusions, and enables more trustworthy downstream analyses of virtual ST.

genomics↗

Multiomic Spatial Imaging Assay (MSIA) -- A High-plex In Situ Detection Method for mRNAs, Proteins, and Protein-Protein Interactions using Manual And Semi-Automated Workflows

We report Multiomics Spatial Image Analysis (MSIA), a suite of technologies that include streamlined manual and semi-automated workflows to image 100s of RNAs from fresh frozen and formalin-fixed paraffin-embedded (FFPE) samples, contextualize RNAs with select protein markers including imaging synaptic protein interactions, a data analysis pipeline that includes corrections for chromatic aberration, algorithms for image stitching, deep learning models for image analysis (cell segmentation and RNA dot detection using hundreds of RNAscope images) from multiple stain-image cycles and proof of concept for a language model trained on extensive Parkinsons Disease (PD) literature. We used the language model to identify potential new biomarkers that were confirmed in MPTP-treated mouse model of PD. Furthermore, by incorporating more stain-image cycles alongside an additional fluorescent channel and advanced error-correcting decoding schemes, the MSIA workflow demonstrates the scalability to potentially quantify over 1,000 genes.

neuroscience↗

The buried S2 apex of SARS-CoV-2 spike elicits an immunodominant germline-restricted public antibody response

The continued mutational pressure on the SARS-CoV-2 S1 subunit underscores the need to target the conserved S2 region for pan-coronavirus vaccine development. A detailed molecular understanding of S2-directed immune responses is therefore essential. In this study, we identified the S2 apex as the most immunodominant epitope within the S2 subunit, eliciting robust antibody responses despite occlusion by S1, using electron-microscopy-based polyclonal epitope mapping (EMPEM) of plasma from infected and vaccinated individuals. Structure-guided sequence analysis with antibody databases revealed that antibodies targeting a poorly characterized S2 Apex-B site form a convergent public clonotype, which is predominantly derived from the IGHV3-30 germline with a 14-residue CDRH3 containing a G/S-G-S/N-Y motif. This clonotype is extensively expanded, accounting for up to 40% of total spike-reactive antibody sequence counts in individual vaccinated donors. This study elucidates the molecular basis the high-frequency elicitation of this non-neutralizing clonotype emphasizing that its immunodominance acts as a primary hurdle for universal coronavirus vaccines and underscore the need for precision antigen design to redirect immunity toward more potent neutralizing targets.

immunology↗

HistoSweep enables cellular-resolution tissue quality control for gigapixel images in digital pathology and spatial omics

High-resolution histology images are indispensable for pathology and increasingly serve as the structural backbone for spatial omics. Yet whole-slide images (WSIs) frequently contain artifacts, acellular voids, and background regions that, when included in computational workflows, introduce noise, degrade model accuracy, and compromise biological interpretation. Existing tools provide only coarse foreground-background separation, leaving a gap in fine-grained quality control (QC). Here we present HistoSweep, a scalable framework that generates morphology-aware tissue masks at cellular resolution. By integrating density filtering, texture descriptors, and adaptive thresholding, HistoSweep systematically removes non-informative tissue regions while preserving biologically meaningful microstructures. It processes billion-pixel WSIs in minutes on standard CPUs, requiring no GPU acceleration, and is deployable across research and clinical settings. Across 25 WSIs spanning distinct tissues, disease states, and spatial omics platforms, HistoSweep consistently outperformed existing methods. It enhanced visualization and segmentation, improved virtual cell type predictions, and safeguarded spatial transcriptomics integrity by detecting transcript leakage and transcript-histology misalignment. By enabling fine-grained, scalable QC, HistoSweep provides a foundational preprocessing step for reliable and reproducible digital pathology and spatial omics analyses.

bioinformatics↗

Heterologous betacoronavirus spike immunization in nonhuman primates elicits cross-reactive antibodies that neutralize both sarbeco- and merbecoviruses

In anticipation of future coronavirus (CoV) pandemics, developing vaccines that elicit broadly neutralizing antibodies (bnAbs) against diverse CoVs is critical. Here, we vaccinated rhesus macaques with SARS-CoV-2 spike (S)-protein, then boosted with heterologous {beta}-CoV S-proteins to focus responses to common conserved S2 bnAb epitopes. Initial SARS-CoV-2 priming elicited receptor-binding domain (RBD)-focused responses, while MERS-CoV boosting redirected responses toward the S2 region, including the stem-helix bnAb site. Although S2-directed serum cross-neutralization was undetectable and most isolated cross-reactive monoclonal antibodies (mAbs) targeted non-neutralizing epitopes, two S2 stem-helix mAbs were identified from memory B cells. These bnAbs neutralized diverse sarbeco- and merbecoviruses, including MERS-CoV, and conferred robust in vivo protection against SARS-CoV-2 challenge. Structural studies revealed that these macaque bnAbs closely mimic human S2-stem bnAbs induced by infection. These findings provide proof-of-principle for vaccination strategies that elicit broadly protective {beta}-coronavirus responses and highlight non-human primates as a translational model for evaluating S2-targeted immunogens.

immunology↗

Abalone genomics reveals an ancient asymmetry axis and the multifunctionality of the mantle

Gastropod diversification represents one of the most spectacular evolutionary radiations, underpinned by a fundamentally asymmetric body plan and diverse pigmentation patterns. To understand the genetic underpinnings of these cardinal traits, we constructed a chromosome-level genome assembly for the rainbow abalone, Haliotis iris. Integrating systematic genomics, histoembryology, and molecular assays, we uncover an ancient regulatory axis, conserved for over 544 million years, in which the long non-coding RNA lncRNA1 functions as a competing endogenous RNA to shield pitx transcripts from miRNA-mediated degradation, thereby driving the establishment of asymmetric body patterning, including the mantle. Furthermore, we identify a wnt-mitf-tyr cascade as the driver of melanogenesis and demonstrate that the mantle is the primary site of melanin synthesis. Concurrently, we reveal the mantle as a multifunctional organ possessing mechanosensory capabilities. These findings elucidate the ancient genetic toolkit governing trait evolution in gastropods. TeaserA deeply conserved RNA switch directs gastropod body plans and reveals the mantles hidden talents.

genomics↗

Theta-mediated conceptual reinstatement in vmPFC precedes perceptual reinstatement in ventral visual cortex during memory recall

When recalling past episodes, different features of an experience, such as conceptual meaning and perceptual detail, are reconstructed and reinstated across distributed cortical regions. However, current models of human memory remain unclear how these feature-specific reinstatements unfold over time, and whether they interact hierarchically during memory retrieval. Using magnetoencephalography (MEG) and time-resolved encoding-retrieval cross-phase classification analysis, we compared the time course of conceptual and perceptual reinstatement during cued visual recall. Conceptual information decoding in the ventromedial prefrontal cortex (vmPFC) preceded perceptual information decoding in the ventral visual cortex (VVC), and the two were expressed in distinct frequency bands: theta (4-8 Hz) for conceptual and gamma (30-40 Hz) for perceptual information. Cross-correlation and spectral Granger causality analyses revealed that during reinstatement conceptual information in vmPFC predicted and directed perceptual information in VVC, with theta-band information flow predominantly from vmPFC to VVC. In addition, bottom-up connectivity from VVC to vmPFC was expressed in the alpha band. These findings suggest that memory retrieval proceeds from abstract conceptual reconstruction to the reinstatement of perceptual details, mediated by theta oscillatory communication between prefrontal and sensory areas. We propose a hierarchical interactive model in which vmPFC initiates conceptual activation through theta-band top-down signals, while VVC provides alpha-band feedback for evaluating reconstructed perceptual details.

neuroscience↗

Widespread loss of Y expression in the absence of transcriptional dosage compensation in Rumex hastatulus

There is growing interest in the potential role of gene regulatory evolution in the expansion and degeneration of Y chromosomes. Evolutionarily young sex chromosomes, such as those found in the flowering plant Rumex hastatulus, can provide insights into the early stages of this process. Using a new high-quality genome assembly with a well-assembled Y chromosome and a highly replicated transcriptome dataset, we found widespread underexpression of Y genes compared to their homologous counterparts on the X chromosome. We also found evidence for increased expression differences for more distantly diverged gametologs, suggestive of progressive loss of expression of Y linked genes over time. Genes with greater expression loss on the Y chromosome also showed elevated rates of protein evolution, as expected if silencing alleles mask the effects of deleterious mutations on the Y and/or if selective interference drives early degeneration in regulatory sequences. However, in contrast with the predictions of recent models of sex chromosome expansion and degeneration by regulatory evolution, there was no evidence of early dosage compensation. Overall, we conclude that in Rumex Hill-Robertson interference alone may be the main driver of Y chromosome degeneration, although further understanding of the temporal order of regulatory changes could help further untangle cause and effect.

genomics↗

Aberrant 5-Methylcytosine tRNA Modification Disrupts Proteostasis and Exacerbates Age-Related Osteoporosis

Age-related protein aggregation drives senile osteoporosis. Aberrant tRNA modifications exacerbate the progression, yet mechanisms linking these to bone loss remain unclear. In this study, we identify Nsun2 (m5C methyltransferase) as key regulator: age-dependent Nsun2 downregulation in BMSCs reduces mC levels of tRNAs, destabilizing tRNAs and impairing translation efficiency of specific transcripts. This directly disrupts the protein synthesis of molecular chaperone and pro-osteogenic factors, accelerating misfolded protein aggregates and activating unfolded protein response, inducing BMSCs senescence and impairing osteogenesis. Mice specifically depleted of Nsun2 exhibited reduced bone mass, whereas mice overexpressing Nsun2 alleviated age-associated bone loss. Notably, the exacerbated protein aggregation and bone mass loss in Nsun2-deficient mice were ameliorated following treatment with the molecular chaperone activator-ML346. Remarkably, ML346 administration proved sufficient to reverse age-related functional deficits in aged mice. Overall, our findings demonstrate that aberrant tRNA-m5C modification alters protein synthesis and induces proteostasis collapse, which constitute a novel contributor to the pathogenesis of senile osteoporosis. Additionally, reduction of protein aggregation through the activation of molecular chaperones presents a promising therapeutic strategy for this disease.

cell biology↗

An antifungal with a novel mechanism of action discovered via resistance gene-guided genome mining

Invasive fungal infections claim over two million lives annually, a problem exacerbated by rising resistance to current antifungal treatments and an increasing population of immunocompromised individuals. Despite this, antifungal drug development has stagnated, with few novel agents and fewer novel targets explored in recent decades. Here, we validate acetolactate synthase (ALS), an enzyme critical for branched-chain amino acid biosynthesis and absent in humans, as a promising target for new therapeutics. Using resistance gene-guided genome mining, we discovered a biosynthetic gene cluster in Aspergillus terreus encoding HB-35018 (1), a novel spiro-cis-decalin tetramic acid that potently inhibits ALS. Biochemical and antifungal assays demonstrate that 1 surpasses existing ALS inhibitors in efficacy against Aspergillus fumigatus and other pathogenic fungi. Structural studies via cryo-electron microscopy reveal a unique covalent binding interaction between compound 1 and ALS, distinct from known inhibitors and finally, we demonstrate that ALS is essential for the virulence in a mouse model of invasive aspergillosis. These findings position ALS as a promising target for antifungal development and demonstrate the potential of resistance gene-guided genome mining for antifungal discovery.

bioengineering↗

Integrated analysis reveals neuro-immune pathway in the central nervous system that supports SGLT2i`s protective effects in treatment of cardiac remodeling

BackgroundDespite growing evidence of sodium-dependent glucose transporters 2 inhibitors (SGLT2i) improving heart failure, their mechanisms remain unclear. This study explored the effects of empagliflozin (EM) on sympathetic nerve activity and potential neuroimmune pathways. MethodsSingle-nucleus RNA sequencing (snRNA-seq) was performed in hypothalamic tissue of a DOCA-salt mouse model to screen for cellular changes. Validation of relevant mechanisms in DOCA-salt and high-salt diet (HSD) mouse models. Additionally, clinical data from 1,189 hospitalized heart failure patients were analyzed to evaluate the translational relevance of the experimental findings. ResultsEM treatment was associated with protective effects against cardiac remodeling in both DOCA-salt and HSD mice. Both models exhibited sympatho-excitation and neuronal hyperactivity in pre-autonomic brain regions, which appeared to be blunted by EM co-treatment. snRNA-seq analysis suggested that cellular interplay among vascular cells, microglia, and inhibitory neurons might be involved in these processes. Specifically, high-salt intake was linked to peripheral immune activation, including lymphocytosis and elevated plasma interferon-{gamma}, which potentially mediated microglial state transitions. EM might counteract the disease-associated upregulation of protein ubiquitination. Clinically, SGLT2i use was significantly associated with reduced lymphocyte counts in specific patient subgroups. ConclusionsEmpagliflozin may attenuate cardiac remodeling caused by high sodium intake through neuroimmune effects by restoring microglial homeostasis and inhibiting sympathetic nerve activity.

molecular biology↗