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Hu, Y.

Publications and source records attributed to Hu, Y..

At least 19 recordsLinked to original sources

MutQA: A Cross-Validated Q&A Dataset for Genetic Mutations

We introduce MutQA, a dataset of 330,387 citation-grounded question-answer (QA) pairs linking genetic mutations to their functional consequences as described in the biomedical literature. Each record pairs a protein-coding mutation with a natural-language question and an evidence-backed answer anchored to sentences in one of 27,442 open-access PubMed Central articles, spanning 6,620 genes and 125,593 gene-variant pairs. The dataset is constructed using CrossValQA, a framework that enforces information isolation between independent LLMs: one model generates QA pairs from an article, a second model answers the same question without access to the first model's response, and a third model judges whether each model's rationale supports the other's answer, so that retained QA pairs are reproducible from the source text rather than hallucinated. Of 401,406 audited QA pairs, 82.7% pass both directions of this cross-validation; those with a recoverable reference protein sequence form the released benchmark. In a 999-pair stratified audit, two expert annotators agree exactly on 86.4% of cross-validated QA pairs (95% CI 83.7-89.0; n = 638), a tier in which about 90% of ratings are "correct". Individual LLM judges agree with individual annotators at a comparable 87.0% on this tier but far less on QA pairs that fail cross-validation. Fine-tuning MutaPLM on MutQA nearly doubles its mean LLM-judge score for question-conditioned mutation-effect answering (1.45 to 2.82 on a 0-5 scale) and improves mutation-recovery accuracy from effect descriptions from 19.4% to 32.1%. Providing variant-matched MutQA retrieval context, without fine-tuning, improves strict answer accuracy across four LLM families by 20.0-28.6 percentage points, demonstrating the framework's ability to improve the reliability of LLM answers. We also apply CrossValQA to proteomics, providing a proof of concept for its use beyond mutation-specific QA. We release the dataset, construction framework, and evaluation code.

genomics↗

Analysis of genome sequences of marine isolates of Saccharomyces cerevisiae

Saccharomyces cerevisiae is the workhorse of the fermentation industry, as well as a dominant laboratory model organism and chassis for synthetic biology. The great majority of known isolates are from terrestrial sources, but a number of strains are reported to have been isolated from seawater and marine sediments and organisms. Marine strains may have superior tolerance to salt and fermentation inhibitors, and other properties which may be useful in industry, especially in processes based on seawater and marine biomass, as well as casting new light on the physiology and evolution of this species. We have recently reported the isolation of several marine strains of S. cerevisiae and comparisons with terrestrial strains for ethanol production. Here we describe the genome sequences of three marine S. cerevisiae strains, AZ65, AZ118 and AZ123. To the best of our knowledge, these are the first genome sequences of marine S. cerevisiae strains for which published isolation data are available. Superior salt and inhibitor tolerance of the strains, compared to multiple terrestrial and industrial comparators, was confirmed. Analysis of the ENA locus, believed to be related to salt tolerance in S. cerevisiae, did not show strong evidence for modification of copy number, protein sequence, or promoter sequence of this locus in response to a marine habitat. The physiological and genetic basis of salt and inhibitor tolerance thus remains to be determined.

microbiology↗

LKOM: Longitudinal Knockoff with Masked Likelihood Ratio for FDR-Controlled Association Discovery

Repeated phenotypic measurements in biobanks can reveal genetic effects on both average trait levels and within-subject variability. However, existing longitudinal genome-wide association methods generally test variants marginally and analyze the two components separately, limiting the localization of signals in linkage disequilibrium and the detection of variants with shared effects. Here we introduce Longitudinal KnockOff with Masked likelihood ratio (LKOM), a multivariable framework that jointly models mean and variability signals while controlling the variant-level false discovery rate for the joint null of no association with either component. LKOM uses model-X knockoffs and masked likelihood-ratio statistics to distinguish original variants from synthetic controls, and assigns selected variants to mean-specific, variability-specific or shared association states. A genetic-relationship-matrix-based whitening extension accommodates related individuals. In simulations, LKOM maintained false discovery rate control across diverse genetic architectures, heavy-tailed errors, reduced longitudinal follow-up and sample sizes up to 100,000. It generally improved power over separate-channel knockoff and marginal association methods, with the largest gains for shared effects and rare variants, particularly when the overall genetic contribution to phenotypic variation was modest. In related samples, whitening restored calibration under dense pedigree structures while preserving power gains over SPAGRM(CCT). LKOM provides an interpretable and scalable approach for identifying conditionally associated variants from longitudinal phenotypes.

bioinformatics↗

Spatial isotope tracing maps compartmentalized nutrient use across the adult fruit fly

Drosophila melanogaster is a powerful model for studying systemic metabolism. Although metabolism is compartmentalized across tissues, prior work in adult Drosophila has mostly measured it in dissected tissues rather than in situ, limiting the spatial information that can be gained. Here, we combine whole-fly mass-spectrometry imaging with stable-isotope tracing and flux modeling to quantify metabolic activities across the adult fruit fly in a spatially resolved manner. Across 68 tracer-fed Oregon-R female flies and 187,709 pixels, we map 81 metabolites onto eight annotated regions, including muscle, fat body, gut, and nervous system. Glucose labeling and fitted relative fluxes indicate higher glycolytic and tricarboxylic acid cycle turnover in thoracic muscle than in abdominal fat body; proline labels the nervous system and eye; glutamine the abdominal reproductive system and gut. Alanine carries glucose-derived carbon through the hemolymph and transfers nitrogen into glutamate. In flies bearing yorkie-driven gut tumors, alanine contribution to malate rises in gut and abdomen, and reducing gut alanine uptake lowers tumor burden. Together, this work establishes a framework for quantitative spatial metabolic analysis, showing compartmentalized nutrient use across the adult fruit fly.

genetics↗

Coronavirus nucleocapsid proteins differentially antagonize RIG-I-like receptor signaling to shape pathogenicity

Coronaviruses cause human infections with divergent clinical outcomes. Viral proteins likely play important roles in the severity of human diseases but are poorly defined. In this study, we discovered that viral nucleocapsid (N) proteins from various human coronaviruses have distinct abilities to antagonize human innate immune responses. N proteins from more pathogenic coronaviruses, such as SARS-CoV and SARS-CoV-2, have more potent activities specifically against human RIG-I-like receptor (RLR) activation than less pathogenic coronaviruses including OC43 and HKU1. Mechanistically, the SARS-CoV-2 N protein interacts with RLR pathway viral RNA sensors MDA5 and RIG-I and inhibits their interaction with MAVS. The CTD of SARS-CoV-2 N protein is an important region for RLR antagonism. Consequently, N proteins from more pathogenic coronaviruses promote viral replication more effectively than N proteins from less pathogenic coronaviruses. Blocking N protein function may be a promising antiviral strategy.

microbiology↗

A minimally modified AAV9 variant (AAV9fyhr) for enhanced CNS gene delivery by intra-CSF administration.

Adeno-associated virus (AAV) mediated gene therapies continue to show promise for the treatment of genetic diseases. However, delivery and safety still represent significant prohibitive barriers restricting translation of these delivery modalities to humans. We describe a novel AAV9 variant, AAV9fyhr or FYHR, identified from screening a controlled randomization point mutation AAV9 library in mice and nonhuman primates followed by directed evolution of in vivo CNS-derived libraries screened in human iPSC differentiated cortical neurons. Capsid variants of interest were identified by coupling long read sequencing and computational structure modeling. Structure-function analysis of our lead candidate reveal that two targeted amino acid changes are sufficient to result in beneficial pleiotropic effects across viral stability, cell surface attachment, and gene delivery. We developed a novel multiplexed barcoding reporter system, enabling a time and cost-effective option to gather spatially resolved single cell capsid validation data in mice and nonhuman primates. When administered intrathecally, AAV9fyhr exhibits 2-to-6-fold higher gene delivery across several tissues in the CNS while minimally altering the tropism to peripheral tissues in comparison to AAV9. These findings demonstrate the potential of whole capsid engineering for the rational development of translational next generation AAV capsids.

bioengineering↗

FlyAnatoView: Visualization of Drosophila Single-cell RNA-seq Datasets on Anatomographs

Single-cell RNA sequencing (scRNA-seq) is a powerful approach for measuring the transcriptomic landscape at single-cell resolution. However, while scRNA-seq data reveals what genes each cell expresses, they do not indicate where that cell was located within the tissue or organ, anatomically. We developed FlyAnatoView (https://www.flyrnai.org/tools/rna_seq_base/web/svg_files/), a resource that projects scRNA-seq data onto anatomical diagrams, restoring this missing spatial context.

bioinformatics↗

CD24-dependent innate immune checkpoint targeting chimera disrupts TGF-β-driven immunosuppression to enhance anti-tumor therapy

The immunosuppressive tumor microenvironment (TME) poses formidable challenges for cancer immunotherapies. Among the complex TME landscape, the cytokine TGF-{beta}1 is an attractive soluble target for reinvigoration of anti-tumor immunity due to its pivotal function in immune cell suppression, extracellular matrix remodeling, and epithelial-to-mesenchymal transition (EMT) promotion, while immune checkpoint receptors exemplified by PD-1 and CD24 are promising surface targets. Though adaptive immune checkpoint inhibition is well established in clinical practice, TGF-{beta} blockade or innate immune checkpoint blockade is yet to be harnessed for tumor treatment. Here, leveraging CD24 overexpression on multiple tumor tissues and its unique recycling kinetics, we designed an innate Immune Checkpoint TArgeting Chimera (ICTAC) G01, a bifunctional CD24 antibody-TGF-{beta}1 receptor fusion protein that disrupts TGF-{beta}1 signaling by TGF-{beta}1 degradation instead of simple blockade and simultaneously inhibits the "don't eat me" CD24 signaling. We demonstrated that G01 effectively suppressed TGF-{beta}1-Smad signaling, reversed the EMT, and attenuated fibrotic collagen deposition. Additionally, it antagonized CD24 signaling to unleash robust antibody-dependent effector activity, further reprogramming the immunologically cold TME toward inflammatory phenotype. By selectively targeting malignant cells while sparing CD24-expressing B cells, G01 demonstrated a favorable safety profile. Notably, in patient-derived tumor fragments (PDTFs), G01 also inflamed the TME, underscoring its translational potential. Together, these results establish ICTAC as an effective strategy for tumor-specific receptor-mediated extracellular protein depletion, which supports its application for reversing TGF-{beta}1; and innate immune checkpoint-mediated tumor immunosuppression by concurrent targeting of both surface and soluble tumor-promoting factors.

immunology↗

A genome-scale ORF screen for resilience factors that protect the RPE and restore vision in aged mice

Aging is a complex phenomenon, yet therapeutic discovery has largely relied on testing individual hypothesis-driven targets. Here, we performed a genome-scale open reading frame (ORF) screen for oxidative-stress resistance in retinal pigment epithelium (RPE) cells, which are vulnerable to oxidative damage during aging. The screen identified nine protective ORFs including antioxidant factors and an epithelial-to-mesenchymal transition regulator. Notably, we also identified three factors that reduce transcriptomic age including the cardiac transcription factor NKX2-5. NKX2-5 conferred robust oxidative resilience in vitro and in vivo. Domain dissection revealed that its homeodomain is dispensable for resilience, enabling development of NKX2-5{Delta}HD, which retained protective activity without detectable toxicity over 14 months. In middle-aged mice, subretinal NKX2-5{Delta}HD restored visual and electrophysiological function, and its systemic delivery improved grip strength and reduced frailty in late-aged mice. These findings highlight the value of unbiased, genome-scale gain-of-function screening, as resilience factors normally expressed in other contexts can be reengineered as potential therapeutics for age-related decline in other tissues.

genetics↗

Listeriolysin O recruits UBA1 to ubiquitinate NLRP3 and suppress inflammasome defence

The NLRP3 inflammasome is a central cytosolic defence pathway against infection, yet intracellular pathogens must restrain this response to preserve their replicative niche. Here we identify a ubiquitin-dependent immune-evasion mechanism in which L. monocytogenes uses listeriolysin O (LLO) to destabilise NLRP3. The N-terminal PEST-like sequence of LLO acted as an adaptor that recruited the host ubiquitin-activating enzyme UBA1 and promoted K48-linked polyubiquitination of NLRP3. This modification drove proteasomal NLRP3 degradation and limited caspase-1 activation, gasdermin D cleavage, IL-1{beta}/IL-18 release, and macrophage pyroptosis. Deleting the PEST region preserved basal haemolytic activity but impaired NLRP3 ubiquitination, thereby enhancing inflammasome activation during infection in macrophages and in vivo. Conversely, UBA1 overexpression suppressed NLRP3-mediated inflammatory responses and supported intracellular bacterial survival. UBA1 depletion restored NLRP3 protein levels, reduced bacterial burden and delayed lethal infection, albeit with increased inflammatory tissue injury. These findings define a ubiquitin-hijacking strategy that operates at the E1 step, whereby a bacterial toxin redirects host ubiquitin activation towards an innate immune sensor.

microbiology↗

An accumbal cholinergic ISR-HCN2 axis sustains maladaptive cue motivation

Environmental cues associated with rewarding outcomes can exert persistent control over behavior long after the reward is absent, yet the cellular adaptations that stabilize such maladaptive motivation remain unclear. Here we identify nucleus accumbens cholinergic interneurons (CINs) as causal regulators of persistent cue-driven seeking. Self-administration of addictive drugs or high-fat reward, but not sucrose, selectively increased CIN pacemaker firing. Cocaine-paired cues evoked rapid acetylcholine release in the nucleus accumbens core, and bidirectional manipulation of CINs suppressed or enhanced cue-induced cocaine seeking. Mechanistically, cocaine experience engaged the integrated stress response (ISR) in CINs, increased HCN2 expression and Ih, and stabilized a hyperexcitable state. CIN-specific ISR suppression or HCN2 knockdown reduced cocaine seeking, whereas HCN2 overexpression enhanced it. Local HCN blockade and systemic treatment with the clinically approved HCN blocker ivabradine reduced cue-driven seeking across addictive-drug and high-fat-reward paradigms while sparing sucrose seeking. These findings identify an ISR-HCN2-dependent cholinergic mechanism that stabilizes maladaptive cue-driven motivation and nominate HCN-dependent excitability as a tractable target for therapeutic intervention.

neuroscience↗

Functional reorganization of large-scale brain systems underlies emotion regulation maturation

Emotion regulation via cognitive reappraisal is essential for socioemotional development and mental health, yet the organizational logic of its supporting brain systems across youth remains unclear. Using a large multisite cohort, we demonstrate that maturation of reappraisal capacity reflects reorganization of a distributed architecture rather than progressive strengthening of prefrontal control. Reappraisal robustly reduced negative affect, with non-linear gains concentrated between 6 and 10.5 years. Bayesian systems identification resolved this architecture into four functionally distinct systems-reappraisal-specific, common-appraisal, modifiable-emotion, and non-modifiable-emotion components-spanning prefrontal-control, salience, default-mode and dorsal-attention networks. Age-related variation in anterior temporal cortex, emerged as essential hub, statistically accounted for developmental gains in reappraisal success. Multivariate modelling together with intersubject analyses further identified a cross-site-generalizable whole-brain reappraisal signature and revealed an age-dependent shift in brain-behaviour coupling, with neurobehavioural convergence increasing with age. These findings establish distributed network reorganization as a core mechanism of emotion regulation development and provide mechanistic targets for stage-matched interventions.

neuroscience↗

A J-protein-licensed CHD3 chromatin remodeling complex promotes H3K27me3 spreading to maintain cell identity in plants

Stable inheritance of epigenetic states is essential for cellular identity and developmental robustness and requires ATP-dependent chromatin remodeling, yet the molecular composition and regulatory mechanisms of plant CHD3 chromatin remodelers have remained unknown. Here we show that the Arabidopsis CHD3 remodeler PICKLE (PKL) assembles with a defined set of J-domain proteins (JDPs) to form stable CHD3 chromatin remodeling complexes in plants that are compositionally distinct from their animal counterparts. Loss of JDPs phenocopies pkl mutants, and JDPs are required for nucleosome densification and H3K27me3 spreading at thousands of Polycomb target genes. Mechanistically, JDPs perform dual functions by promoting PKL protein stability while directly stimulating PKL chromatin remodeling activity through their plant-specific DUF3444 domain that binds the N-terminal tail of histone H3. Deletion of the DUF3444 domain severely impairs PKL remodeling activity without disrupting complex assembly, leading to defective H3K27me3 spreading, impaired facultative heterochromatin maintenance, and loss of cell identity. Together, our findings define plant CHD3 chromatin remodeling complexes and reveal a mechanism that regulates CHD3-mediated chromatin remodeling to support the propagation of repressive chromatin states in plants.

plant biology↗

Atlas-scale single-cell analysis beyond in-memory paradigm with scAtlasPy

Single-cell atlases are rapidly outgrowing the memory capacity of standard workstations, challenging the in-memory paradigm underlying mainstream computational ecosystems. Here, scAtlasPy decouples scale of atlas from memory capacity by leveraging the disk-resident computing. It enables full-resolution analysis of a 100-million-cell atlas with only 42.9 GB peak memory, whereas state-of-the-art platforms are limited at 3 million cells with 512 GB memory. scAtlasPy achieves 137,745 cells/s, 10.4x faster than scDataset with 82.6% lower memory usage for random minibatch retrieval. Its extensible architecture offers a flexible platform for diverse atlas-scale analytical tasks, facilitating the discovery of complex cellular heterogeneity and functions in massive cell atlases.

bioinformatics↗

A patient-centric therapeutic paradigm uncouples prostate cancer suppression from systemic metabolic collapse

The clinical benefits of cancer therapies are often compromised by the tolerable adverse effects that impair systemic organismal health and may evolve into latent life threats. Here, we identified profound abiraterone-induced but androgen-independent metabolic perturbations in prostate cancer patients and developed Lifehug-9892 to balance tumor therapy with systemic metabolic homeostasis. By integrating population cohorts with high-resolution metabolomics, we demonstrate that abiraterone induces profound systemic lipidomic dysregulation, characterized by the massive, pathological accumulation of desmosterol. Abiraterone inhibits but stabilizes DHCR24, leading to a metabolic trap in patients showing elevated levels of both desmosterol and cholesterol. Desmosterol accumulation is highly lipotoxic, potently triggering endothelial cell senescence and necrosis, macrophage foam cell formation, murine atherosclerosis, and hepatic senescence. To mechanistically uncouple and therapeutically rescue this systemic metabolic collapse, Lifehug-9892 was rationally designed to selectively retain on-target CYP17A1 inhibition while completely sparing DHCR24 function. Lifehug-9892 maintains potent tumor-suppressive activity while fully preserving the desmosterol-cholesterol metabolic axis and preventing systemic cardiovascular and hepatic damage. Our study uncovers a critical mechanistic link between drug-induced metabolic dysregulation and organismal health in cancer patients, providing a biochemical framework for developing patient-centric targeted therapies that preserve host homeostasis.

cancer biology↗

Extracellular water withdrawal drives disease resistance in the phyllosphere

A central question in immunity is how hosts arrest pathogen growth. Diverse plant pathogens create a water-soaked niche in host tissue essential for pathogenesis, yet how water shapes infection outcome is unknown. Using genetics and hyperspectral imaging, we show that extracellular water status is rate-limiting for both compatible and incompatible interactions. We find that the hypersensitive response of effector-triggered immunity (ETI) is, mechanistically, a desiccation event. Water loss imposes osmotic stress that arrests bacterial division while the pathogen remains alive and metabolically active, rather than killing it. Restoring apoplastic water reverses this stasis and licenses growth despite intact immune signaling and cell death. Water status, not immune signaling per se, gates pathogen growth. This reframes ETI as a controlled desiccation mechanism and identifies hydration as a decisive lever on disease outcome.

plant biology↗

Why This Code? A Constrained Mapping Framework for the Evolutionary Stability of the Canonical Genetic Code

The canonical genetic code is used by most known forms of life, yet explaining its historical origin and present day functional performance requires comparison with the enormous space of possible codon-to-output assignments. Here, the code is formulated as a hierarchy of constrained mapping problems spanning codeword length, degeneracy composition, synonymous-block partitioning, semantic assignment and a coarse decoder layer. Exact structural analyses identify triplets as a Pareto choice under a fixed-length full-codebook model and show that anonymous degeneracy statistics alone do not explain the canonical profile. Within a fixed canonical block architecture and under specified objective functions, recurrent AAindex-based rule learning contracts the 20! amino-acid assignment space to 2.72 ** 1011 admissible mappings, from which 108 complete codes are sampled. In this screened conditional candidate library, the standard genetic code ranks in the best 0.9749% under the equal-weight three-objective score and in the best 1.801% when accessible replacement diversity is added. Sensitivity analyses show that this position is broad across many, but not all, tested objective weights and aggregation rules. These results describe a conditional multi-objective compromise; they do not establish global optimality, historical inevitability or cellular feasibility of decoder redesign.

evolutionary biology↗

The Drosophila Secretome

Secreted proteins are synthesized within the cell and actively transported outside, where they contribute to development, physiology, immunity, and cellcell communication. In Drosophila melanogaster, many secreted signaling pathways are evolutionarily conserved, making this species a powerful model for studying human development, cancer, neurobiology, and immune regulation. To assemble the Drosophila secretome, we systematically analyzed all fly protein sequences with computational tools, integrating FlyBase, UniProt and Gene Ontology annotations, and incorporating large-scale proteomics datasets. We identified 4,831 genes encoding putative secreted proteins, assigned confidence scores based on the type and strength of supporting evidence, and generated an online resource (www.flyrnai.org/apps/fly_secretome/) for exploring these data. Comparison with the human secretome shows that 54% of Drosophila secretome genes are conserved in the human genome and of these, 83% are annotated as secreted in human. In addition, comparison with Drosophila single-cell transcriptomic data revealed that secreted proteins are more tissue-specific than other genes. Finally, we demonstrate the utility of this resource by analyzing changes in expression of genes encoding putative secreted proteins during aging based on snRNA-seq datasets from the Aging Fly Cell Atlas.

genetics↗