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Liu, Y.

Publications and source records attributed to Liu, Y..

At least 685 records · Page 38Linked to original sources

Impact of Inactivation Methods on Biosafety and Antigen Reactivity of Brucella melitensis from the Perspective of Astral-DIA Proteomics Based on Antibody Immunoprecipitation Mass Spectrometry

Effective Brucella inactivation is imperative for safe vaccine development, diagnostics, and sample handling, particularly in resource-limited regions lacking high-level containment facilities. This study investigated inactivation methods using the Rev.1 vaccine strain and three Brucella melitensis field isolates from Gansu (GS-XG, GS-SN, GS-MQ). Heat (80{degrees}C/95{degrees}C, 10-20 min) and formaldehyde (0.4%/0.6%, 48-72 h) inactivation were evaluated for biosafety and antigenicity. Rev.1 was completely inactivated by 80{degrees}C/95{degrees}C for 20 min or 0.6% formaldehyde for 48-72 h. Superior antigenicity, compared to phenol inactivation, was confirmed by ELISA and Western Blot. However, field isolates demonstrated greater resistance, surviving 80{degrees}C for 20 min and 0.4% formaldehyde for 72 h, necessitating stricter conditions (95{degrees}C, 20 min; 0.6% formaldehyde, 72 h) for their complete inactivation. Astral-DIA proteomics analyzed approximately 60% of the proteome ([~]2000/3300 proteins), revealing 256, 311, and 318 differentially expressed proteins between 80{degrees}C/95{degrees}C heat, 48-h/72-h formaldehyde, and heat/formaldehyde methods, respectively. Gene Ontology and KEGG analyses indicated heat inactivation upregulated cellular structure proteins but downregulated metabolic pathways, with 95{degrees}C potentially damaging conformational epitopes. Formaldehyde treatment (48 h) stabilized soluble antigens, preserving ribosomal and regulatory protein epitopes, while 72-h treatment induced organelle disintegration. Protein-Protein Interaction networks suggested heat inactivation enhanced immunogenicity of membrane and stress proteins, suitable for targeted studies, whereas formaldehyde preserved broader epitopes, beneficial for whole-cell vaccines and multi-epitope screening. Inactivation methods must be tailored to specific strain characteristics and applications. Astral-DIA provides molecular insights into antigenicity loss, guiding future research on protein functions and epitope dynamics for precise brucellosis control.

microbiology↗

Novel Spatial-Structural-Zero-Aware Dissimilarity Measures for Subtype Discovery Using Single Cell Hi-C Data

High-throughput single-cell Hi-C (scHi-C) technologies have opened new avenues for investigating cell-to-cell variability in the three-dimensional organization of the genome within individual nuclei. Despite their potential, analyses of scHi-C data are hindered by data sparsity, which varies substantially across cells. To address this challenge, recent methods aim to denoise scHi-C data and differentiate between two types of zero entries: structural zeros (SZs), which reflect true absence of contacts due to biological structure, and dropouts (DOs), which arise from insufficient sequencing depth. However, current dissimilarity measures used in downstream analyses, such as Euclidean distance and Kendalls tau, treat all zeros as equivalent, thus do not distinguish between SZs and DOs nor recognize the special role of SZs in capturing cell-to-cell variability. Such oversight limits the ability to accurately capture biologically meaningful differences between cells. In this study, we introduce structural-zeros-aware Kendalls tau (szKendall), a novel dissimilarity metric that explicitly incorporates the spatial structure of 2D contact matrices and leverages the presence or absence of shared SZs across cells. Through comprehensive simulations and analysis of real scHi-C datasets, we demonstrate that szKendall more effectively captures key structural features and achieves superior performance in cell clustering tasks compared to existing approaches. Our results underscore the importance of SZ-aware dissimilarity measures in advancing single-cell 3D genomics.

genomics↗

A trade-off mechanism underpins the evolution of a young two-gene sex-determining system in plants

Sexual systems in animals and plants are remarkably diverse, with dioecy having evolved independently in numerous lineages. In plants, dioecy often evolved more recently than in the best-studied animal systems, making plants especially important for understanding how separate sexes evolved independently from functionally hermaphrodite ancestors. Despite long-standing theories of developmental trade-offs in sex allocation, the underlying genetic mechanisms remain elusive. Here, we show that the XY sex determination system in the dioecious plant species Eurycorymbus cavaleriei in Sapindaceae involves two Y-linked mutations that act jointly within the developmental male-female trade-off: YUN{Delta}, a truncated allele that lowers the dosage of the D-class MADS-box gene YUN, and SUNMAO, a novel sRNA locus that silences the X-linked SUN allele. In females, SUN stabilizes the HD-ZIP transcription factor KUN, which is a known sex determinant in another dioecious plant, thereby promoting femaleness by increasing YUN expression; loss of SUN expression, together with the effect of YUN{Delta}, shifts development toward males. Two interlocking regulatory loops in this "SKY" module (SUN-KUN-YUN) fine-tunes YUN dosage. This dioecious system in E. cavaleriei likely evolved by sequential mutations in genes acting in the predicted male-female trade-off system, with their close linkage reflecting a translocation, and later recombination-suppressing inversions.

plant biology↗

A high-quality bread wheat genome unravels adaptive evolution of wheat end-use quality

Understanding the genetics of superior dough performance is essential for improving wheat end-use quality. Here, we presented a de novo assembly of the genome of JM44, a Chinese wheat cultivar known for its exceptional end-use quality. The JM44 genome achieved reference-level quality (QV = 66.74), depicting a complete picture of complex regions containing gluten genes. Our microsynteny analysis across the Triticum-Aegilops complex showed that high-molecular-weight glutenin subunits (HMW-GSs) loci are highly conserved, while low-molecular-weight glutenin subunits (LMW-GSs) and -/{beta}-gliadins exhibited greater structural variation. These variable loci appear to have been preferentially selected by humans and contributed substantially to the evolution of wheat quality traits. Moreover, we observed that epistatic interactions between gluten genes are strong in modern cultivars, but markedly weaker in landraces, indicating the importance of epistatic selection during modern breeding. Our findings shed light on the genomics and evolution of wheat quality traits, providing valuable guidance for future breeding efforts.

genomics↗

Human hippocampal ripples loosen medial prefrontal constraints to foster creative thinking

Creative thinking often requires breaking away from dominant mental schemas to generate novel and useful ideas. Yet how the human brain relaxes schematic constraints to enable creativity remains unclear. Using human intracranial EEG recordings, we found that moments of creative idea generation were accompanied by increased hippocampal ripple events, a concurrent reduction in ripple-triggered high-frequency activity in the medial prefrontal cortex (mPFC), and greater divergence of ripple-triggered mPFC activity patterns from the typical, schema-like task state. These effects followed a dorsal-ventral gradient within the mPFC and were most pronounced in the ventromedial PFC (vmPFC), a region heavily involved in schematic representation. Together, our findings suggest that hippocampal ripples can transiently disengage medial prefrontal schema constraints, thereby promoting more flexible and creative thinking.

neuroscience↗

Targeting RUNX1 in Macrophages Facilitates Cardiac Recovery

Despite advances in disease treatment, our understanding of how damaged organs recover and the mechanisms governing this process remain poorly defined. Here, we mapped the transcriptional and regulatory landscape of human cardiac recovery using single cell multiomics. Macrophages emerged as the most reprogrammed cell type. Deep learning identified the transcription factor RUNX1 as a key regulator of this process. Macrophage-specific Runx1 deletion recapitulated the human cardiac recovery phenotype in a chronic heart failure model. Runx1 deletion reprogrammed macrophages to a reparative phenotype, reduced fibrosis, and promoted cardiomyocyte adaptation. RUNX1 chromatin profiling revealed a conserved regulon that diminished during recovery. Mechanistically, the epigenetic reader BRD4 controlled Runx1 expression in macrophages. Chromatin activity mapping, combined with CRISPR perturbations, identified the precise regulatory element governing Runx1 expression. Therapeutically, small molecule Runx1 inhibition was sufficient to promote cardiac recovery. Our findings uncover a druggable RUNX1 epigenetic mechanism that orchestrates recovery of heart function.

immunology↗

Overcoming breeding constraints in polyploid oat from evolutionary insights

Polyploidy provides adaptive advantages in plants by buffering deleterious mutations1,2. While polyploidization can enhance agronomic traits such as increased biomass, known as the gigas effect1-4, increasing genetic gain in polyploid crops remains a critical but difficult goal due to the difficulty in dissecting complex trait inheritance5,6. Here we present chromosome-scale genome assemblies for 26 Avena taxa, spanning diploid, tetraploid, and hexaploid lineages. We traced four independent polyploidization events across the genus, including the formation of A. agadiriana as an allotetraploid (AgAgAg'Ag'), and revealed a reticulate evolutionary history shaped by gene flow involving four subgenomes (A, B, C, D), for example, the hybrid speciation of A. hirtula. Transcriptomic analysis of 286 samples across 11 tissues, combined with deleterious mutation analysis from a cultivated population of 112 accessions, showed that polyploidization led to widespread functional redundancy among homoeologs, supporting a genome-wide buffering effect. However, derived allele frequency analysis revealed that, while disrupting functional genes may yield desirable traits, the buffering effect impedes the fixation of beneficial loss-of-function mutations and thereby limits breeding efficiency. Based on these integrative analyses, we propose breeding strategies to circumvent these limitations by targeting beneficial loss-of-function alleles within the complex polyploid background of oat. Our study highlights broader challenges in the improvement of polyploid crops and provides a foundation for future breeding strategies.

evolutionary biology↗

Two Spag6 genes control sperm formation and male fertility in mice

Sperm-associated antigen 6 (SPAG6) is the mammalian orthologue of Chlamydomonas PF16, a central axonemal protein essential for flagellar motility. In mice, two homologous genes have been identified: the ancestral Spag6 on chromosome 2 and the evolutionary derived Spag6l on chromosome 16. Although Spag6 knockout mice (Spag6-/-) are phenotypically normal, the surviving Spag6l-/- males are infertile. To further investigate the roles of SPAG6 and SPAG6L, we generated compound mutants by crossing the two knockout lines. Compound heterozygous Spag6+/-; Spag6l+/- mice are fertile, while all Spag6-/-; Spag6l+/- males are infertile despite grossly normal appearance. Histological and ultrastructural analyses revealed defective spermiogenesis, including abnormal chromatin condensation, malformed acrosome and manchette, and disorganized mitochondrial and fibrous sheath. Both SPAG6 and SPAG6L bind to SPINK2, a key regulator of acrosome function, but SPAG6 has an approximately 10-fold higher binding affinity than SPAG6L. Moreover, SPAG6 modulates testicular AKAP4 and SPAG16L levels, which are critical components of the fibrous sheath and central apparatus respectively. Notably, SPAG6 suppresses tubulin acetylation, whereas SPAG6L enhances this post-translational modification, suggesting antagonistic roles in microtubule assembly. Overall, our findings demonstrate that SPAG6 and SPAG6L coordinately regulate sperm formation and male fertility during evolution.

developmental biology↗

Deep-learning triage of 3D pathology datasets for comprehensive and efficient pathologist assessments

Standard-of-care slide-based 2D histopathology severely undersamples spatially heterogeneous tissue specimens, with each thin 2D section representing <1% of the entire tissue volume (in the case of a biopsy). Recent advances in non-destructive 3D pathology, such as open-top light-sheet microscopy (OTLS), enable comprehensive high-resolution imaging of large clinical specimens. While fully automated computational analyses of such 3D pathology datasets are being explored, a potential low-risk route for accelerated clinical adoption would be to continue to rely upon pathologists to provide final diagnoses. Since manual review of these massive and complex 3D datasets is infeasible for routine clinical practice, we present CARP3D, a deep learning triage framework that identifies high-risk 2D cross sections within large 3D pathology datasets to enable time-efficient pathologist evaluation. CARP3D assigns risk scores to all 2D levels within a tissue volume by leveraging context from a subset of neighboring depth levels, outperforming models in which predictions are based on isolated 2D levels. In two use cases - risk stratification based on prostate cancer biopsies and screening for dysplasia/cancer in endoscopic biopsies of Barretts esophagus - AI-triaged 3D pathology, enabled by CARP3D, demonstrates the potential to improve the detection of high-risk diseases in comparison to slide-based 2D histopathology while optimizing pathologist workloads.

pathology↗

Multifunctional Injectable GelMA Hydrogels with MSN-Mediated Spatiotemporal Icariin Release for Enhanced Osseointegration in Bone Defects

The repair of bone defects is faced with the dual challenges of limited autograft donors and single function of artificial materials. The development of new materials with mechanical adaptability, drug-controlled release and osteogenic induction has become a research hotspot in bone tissue engineering. Here, we developed an injectable photocrosslinkable hydrogel by integrating icariin (ICA)-loaded mesoporous silica nanoparticles (MSN) into gelatin methacryloyl (GelMA). The amino-functionalized MSN enhanced compressive modulus by 1.5-fold (p < 0.05) and enabled pH-responsive ICA release (91.2{+/-}4.2% cumulative release over 15 days). Our in vitro findings revealed the composite hydrogel promoted BMSC proliferation was 1.43{+/-}0.04 times that of GelMA group. And express excellent osteogenic differentiation ability (ALP activity: 3.25-fold; Mineralization: 5.01-fold). In vivo study, Micro-CT revealed significantly higher bone volume fraction (BV/TV) in rat calvarial defects at 12 weeks, with histology confirming mature trabecular bone formation. This MSN-mediated spatiotemporal delivery system synchronizes immunomodulation and osteogenesis, offering a promising strategy for non-load-bearing osseointegration.

bioengineering↗

Gut microbes mediate the synergistic effects of dietary cholesterol and saturated fat in driving fibrosing MASH

Metabolic dysfunction-associated steatotic liver disease (MASLD) affects approximately one-third of the global population and can progress to metabolic dysfunction-associated steatohepatitis (MASH) with fibrosis, increasing risk of cirrhosis, hepatocellular carcinoma, and mortality. Gut microbes driven by diets high in saturated fat, simple sugar, and cholesterol contribute to disease progression, yet underlying mechanisms remain undefined. We explored the independent and synergistic effects of dietary saturated fat and cholesterol on MASH development using specific pathogen-free (SPF) and germ-free (GF) mice. We demonstrate that 1) both dietary cholesterol and saturated fat are required to induce fibrosing MASH in SPF mice, whereas GF mice are protected, 2) saturated fat and cholesterol individually alter gut microbial membership, potentially via altered bile acid metabolism, while their combination promotes a distinct composition, including an increase in Parasutterella spp. which correlates with hepatic fibrosis, and 3) diluted cecal contents from SPF, but not GF, mice fed high-fat, high-cholesterol diets are enriched in deoxycholic acid and activate human hepatic stellate cells in vitro, suggesting a mechanistic link between dietary lipid-induced microbiota and liver fibrogenesis. These findings reveal how specific Western dietary components shape the gut microbiota and contribute to hepatic liver fibrosis via stellate activation, offering potential targets for therapeutic intervention in MASLD/MASH.

physiology↗

A Network-Based Discovery of Prognostic Markers in Recurrent IDH wild-type Gliomas

BackgroundIsocitrate dehydrogenase wild-type (IDH wild-type) gliomas represents the most aggressive subtype of diffuse gliomas, characterized by therapeutic resistance and dismal prognosis. Despite advances in molecular classification, reliable prognostic biomarkers for these tumors remain limited, particularly for recurrent disease. This study aims to identify gene expression signatures associated with survival outcomes in recurrent IDH wild-type gliomas, with the goal of improving patient stratification and potential therapeutic targeting. MethodsWe analyzed gene expression data from 180 recurrent IDH wild-type glioma samples from the Glioma Longitudinal AnalySiS (GLASS) Consortium. Using multiple computational approaches including a novel network-based method (netSurvival) and various survival analysis techniques, we identified genes associated with patient survival outcomes. ResultsOur comprehensive analysis identify several gene expression markers that are significantly associated with survival outcomes in recurrent IDH wildtype gliomas. The AFT log normal model revealed that FN1, HIF3A, and EIF4B are associated with poorer survival (hazard ratios of 1.40, 1.49, and 1.54, respectively; p {inverted exclamation} 0.05), while PTK2, CCND2, RAD51L3 RFFL, and MAX demonstrated protective effects (hazard ratios of 0.76, 0.78, 0.79, and 0.79, respectively; p {inverted exclamation} 0.05). Five genes (KIF5C, LINC00632, B4GALNT3, HIF3A, and RAD51L3 RFFL) show significant differential expression between primary and recurrent tumors, with four having established functional roles in glioma pathobiology. ConclusionThis study identifies a panel of gene expression markers with significant prognostic value in recurrent IDH wild-type gliomas. The differential impacts of these genes on survival outcomes provide insights into the biological heterogeneity underlying clinical behavior in these aggressive tumors. Particularly significant are the biomarkers associated with both survival outcomes and recurrence patterns, which may represent key drivers of disease progression. These findings represent an important step toward improved prognostic stratification and therapeutic targeting in IDH wild-type gliomas, addressing a critical unmet need in neuro-oncology.

bioinformatics↗

Self-limiting population suppression gene drive in the West Nile vector mosquito, Culex quinquefasciatus

Culex mosquitoes transmit major pathogens including West Nile virus, encephalitis, filariasis, and avian malaria, threatening public health, poultry, and ecosystems. We engineered a CRISPR-based population suppression gene drive targeting a conserved exon of the doublesex (dsx) gene. The drive incorporates a recoded dsxM segment to preserve male function while converting genetic females into sterile intersexes, enabling male-biased propagation and removal of fertile females. It achieves super-Mendelian inheritance ([~]71%) and generates partially dominant sterile resistance alleles via end-joining, resulting in intersex phenotypes with reduced fertility and hatchability. Modeling predicts that this RIDD (Release of Insects carrying a Dominant-sterile Drive) system can suppress populations at low intrinsic growth rates and release ratios, outperforming SIT and fs-RIDL strategies in persistence and efficiency, with further gains achievable through improved cleavage rates. This study establishes a self-limiting gene drive framework for Culex suppression, highlightling the potential of targeting conserved sex-determination pathways for sustainable vector control.

genetics↗

Telomere replication stress-induced DNA damage response triggers inflammatory signaling via canonical and non-canonical STING pathways

Telomeres are protected by the shelterin complex, but they are also common fragile sites and are particularly susceptible to replicative stress. We found that depletion of telomeric repeat-binding factor 1 (TRF1), a key shelterin component essential for telomere replication, in mouse embryonic fibroblasts (MEFs) activated ATR- and subsequent ATM-dependent DNA damage responses. TRF1 loss increased the formation of micronuclei and cytosolic DNA, leading to ATR-dependent micronuclear rupture and activation of the cGAS/STING pathway. ATM activation enhanced STING K63 modification, thereby boosting the STING/NF{kappa}B pathway. Inhibition of ATM or cGAS reduced the expression of the pro-inflammatory cytokine IL6, with combined inhibition further suppressing IL6 levels. Depletion or inhibition of STING alone decreased production of IL6 and IFN{beta}, with no major reduction by combined ATM and/or cGAS inhibitors. These findings indicate that STING acts epistatically with ATM- and cGAS-mediated inflammatory responses. Overall, the telomere replication stress and dysfunction triggered by loss of TRF1 promotes inflammation through the ATR/cGAS/STING and ATM/STING pathways.

genomics↗

SVPG: A pangenome-based structural variant detection approach and rapid augmentation of pangenome graphs with new samples

Breakthrough advances in long-read sequencing technologies have opened unprecedented opportunities to study genetic variations through comprehensive pangenome analysis. However, the availability of structural variant (SV) calling tools that can effectively leverage pangenome information is limited. In addition, efficient construction of pangenome graphs becomes increasingly challenging with acquisition of larger number of samples. In this study, we present SVPG, an approach that leverages haplotype-resolved pangenome reference for accurate SV detection and rapid pangenome graph augmentation from long-read sequencing data. Compared to state-of-the-art SV callers, SVPG maintained superior overall performance across different sequencing technologies and coverages. SVPG also achieved notable improvements in calling rare and individual-specific SVs on both simulated and real somatic datasets. Furthermore, in a benchmark involving 20 samples, SVPG accelerated pangenome graph augmentation by nearly 10-fold compared to traditional augmentation strategies. We believe that this novel SVPG method, has the potential to revolutionize SV detection and serve as an effective and essential tool, offering new possibilities for advancing pangenomic research.

bioinformatics↗

OrthoFinder: scalable phylogenetic orthology inference for comparative genomics

Here, we present a major advance of the OrthoFinder method. This extends OrthoFinders high accuracy comparative genomic framework to provide substantially enhanced scalability and accuracy. Specifically, we show that enhanced phylogenetic delineation of orthogroups provides a 7% relative increase in orthogroup inference accuracy. We further demonstrate that a new gene assignment method substantially reduces overall runtime RAM usage without compromising accuracy. The latest version of OrthoFinder is available at https://github.com/OrthoFinder/OrthoFinder.

bioinformatics↗

Integrative Species Delimitation in a Speciation Continuum: Phylogenomics, Cryptic Diversity, Diversification and Historical Biogeography of Sinocyclocheilus Cavefish

The transition from structured populations to distinct species often unfolds along a speciation continuum. However, empirically dissecting this continuum poses challenges for species delimitation, particularly in rapid radiations marked by recent divergence, incomplete lineage sorting, and gene flow. The species-rich Sinocyclocheilus cavefish radiation of Southwest China, an emerging evolutionary multi-species model system, shows a notable mismatch between its high morphological diversity and the limited divergence observed in commonly used mitochondrial DNA markers. This pattern suggests that true species richness may be underestimated. Yet, comprehensive genome-wide approaches to resolve species boundaries in this group are still lacking. To address this, we combine phylogenomics, coalescent-based species delimitation, population genetics, and historical biogeography, using both genome-wide RAD-seq and multi-locus Sanger data (including nuclear and mitochondrial DNA). Our phylogenomic analyses resolve major clades and reveal substantial cryptic diversity, well beyond what was detected by earlier markers. Species delimitation based on RAD-seq genomic data identifies several cryptic evolutionary lineages. We recover a dynamic divergence history shaped by isolation and episodic connectivity. Biogeographic reconstruction supports a mid-Miocene origin following a major vicariance event, with subsequent founder-event dispersals into subterranean habitats. This long history of fragmentation is further complicated by reticulation and ancestral polymorphism, and is reflected in present-day patterns of restricted gene flow across river valleys. These results highlight the utility of integrative genomic approaches in resolving species boundaries and uncovering the evolutionary processes that underlie high diversity in large and complex radiations.

evolutionary biology↗

Parameter-wise predictions and sensitivity analysis forrandom walk models in the life sciences

Sensitivity analysis characterises input-output relationships for mathematical models, and has been widely applied to deterministic models across many applications in the life sciences. In contrast, sensitivity analysis for stochastic models has received less attention, with most previous work focusing on well-mixed, non-spatial problems. For explicit spatio-temporal stochastic models, such as random walk models (RWMs), sensitivity analysis has received far less attention. Here we present a new type of sensitivity analysis, called parameter-wise prediction, for two types of biologically-motivated and computationally expensive RWMs. To overcome the limitations of directly analysing stochastic simulations, we employ continuum-limit partial differential equation (PDE) descriptions as surrogate models, and we link these efficient surrogate descriptions to the RWMs using a range of biophysically-motivated measurement error models. Our approach is likelihood-based, which means that we also consider likelihood-based parameter estimation and identifiability analysis along with parameter sensitivity. The new approach is presented for two important classes of lattice-based RWM including a classical model where crowding effects are neglected, and an exclusion process model that explicitly incorporates crowding. Our workflow illustrates how different process models can be combined with different measurement error models to reveal how each parameter impacts the outcome of the expensive stochastic simulation. Open-access software to replicate all results is available on GitHub.

biophysics↗