Biology subjects

Liu, H.

Publications and source records attributed to Liu, H..

At least 145 records · Page 8Linked to original sources

bioRxiv2026

Looking backward for the future: long-term population recovery, habitat associations, and future climatic vulnerability of the critically endangered Sino-Mongolian beaver (Castor fiber birulai) in China

Despite the successful population recovery of the Eurasian beaver (Castor fiber) across much of Eurasia, its subspecies, the Sino-Mongolian beaver (C. f. birulai), remains critically endangered, with an estimated population of approximately 1,500 individuals confined to a small number of isolated and fragmented refugia along the China-Mongolia border. Effective conservation of this highly threatened subspecies requires a holistic perspective that integrates constraints on population dynamics, habitat associations, and future climatic vulnerability. Here, we combined systematic annual field surveys conducted between 2003 and 2023 with historical survey records from 1975 to 1989 in northern Xinjiang, China, to synthesize long-term spatiotemporal population dynamics, evaluate habitat preferences based on nine local environmental variables, and assess future climatic vulnerability using ensemble species distribution models (SDMs) under projected climate change scenarios. We detected a significant and phased population recovery, with beaver colony numbers increasing from 27 (approximately 100 individuals) in 1975 to 227 (681-908 individuals) in 2023. This recovery closely corresponded with major conservation milestones, including the establishment and upgrading of nature reserves, strengthened legislative protection, and enhanced multi-stakeholder collaboration. Habitat analyses further indicated that the Sino-Mongolian beaver preferentially occupied areas characterized by minimal anthropogenic disturbance and stable hydro-geomorphic conditions. Critically, SDM projections revealed that only 14% of the current study area presently exhibits high climatic suitability, and these highly suitable habitats are expected to disappear entirely by the 2050s. Together, our findings provide a comprehensive overview of the historical population recovery and conservation trajectory of the Sino-Mongolian beaver in China, and offer robust scientific support for developing adaptive management strategies in the face of ongoing climate change and increasing human pressures.

ecology↗

bioRxiv2026

Integrative Single-Cell Epigenomic Atlas Annotates the Regulatory Genome of the Adult Mouse Brain

Histone modifications underpin the cell-type-specific gene regulatory programs that drive the remarkable cellular diversity of the mammalian brain. Here, we jointly profiled four histone modifications and the transcriptome in 2.5 million nuclei from the adult mouse brain. By integrating these data with chromatin accessibility, DNA methylation, and three-dimensional genome organization, we constructed a unified epigenomic atlas spanning over 100 brain cell subclasses, and assigned active, primed, and repressive chromatin states across 81% of the genome. Active chromatin states marked by combinatorial histone modifications better nominate candidate enhancers with functional support than chromatin accessibility alone, while H3K27me3- and H3K9me3-marked chromatin states delineate distinct modes of cell-type-specific gene repression. Finally, this multimodal resource enables deep learning models that predict cell-type-specific epigenomic features and gene expression from DNA sequence, providing a comprehensive framework for annotating the brain regulatory genome and interpreting non-coding disease risk variants. HIGHLIGHTS- A single-cell epigenome atlas of transcription and four histone modifications across 2.5M mouse brain cells - Multimodal integration maps chromatin states across [~]81% of the adult mouse brain genome - Cell-type-resolved chromatin landscapes reveal regulatory programs mediated by enhancers, Polycomb and H3K9me3 - Deep learning models predict cell-type-specific epigenomic features and gene expression from DNA sequence

genomics↗

bioRxiv2026

Detection of Somatic Point Mutations Directly from Spatial Transcriptomics Enables in vivo Spatiotemporal Lineage Tracing

Spatial transcriptomics reveals tissue organization but lacks in vivo lineage-tracing methods applicable to humans. We introduce SpaceTracer, a computational framework that accurately detects somatic single-nucleotide variants (SNVs) directly from spatial transcriptomics data. By leveraging naturally occurring somatic SNVs, SpaceTracer reconstructs cellular phylogenies within native tissue architecture, enabling the mapping of lineage spread, migration, lineage-coupled expression changes and lineage-aware local interactions. Applied to human cutaneous squamous cell carcinoma, it traced tumor initiation and progressions, uncovered widespread pre-invasive migration of dedifferentiated epithelial cells and characterized mutant B cells migrating from tertiary lymphoid structures (TLS) into the tumor boundary. The framework also reconstructed developmental lineages across multiple tissues and identified tissue-resident mutant immune cells. SpaceTracer thus provides a perturbation-free platform for high-resolution spatiotemporal lineage tracing, offering a transformative tool for elucidating complex biological systems--especially tumor-immune ecosystems--with direct implications for advancing cancer immunotherapy.

bioinformatics↗

bioRxiv2026

PhyloSOLID: Robust phylogeny reconstruction from single-cell data despite inherent error and sparsity

While lineage tracing based on somatic mutations in single-cell sequencing data offers a powerful approach to reconstructing cellular histories in vivo, its reliability is fundamentally limited by pervasive technical artifacts--specifically, high error rates and data sparsity. These issues introduce false phylogenetic signals that corrupt tree topology and lead to spurious evolutionary conclusions. To overcome these limitations, we present PhyloSOLID, a phylogenetic algorithm designed to be inherently robust to these data imperfections. PhyloSOLID employs a progressive scaffolding strategy that begins with graph-based construction of a low-resolution, high-confidence backbone tree from reliable and uniformly covered mutations. This scaffold is then refined through the iterative integration of remaining data, guided by a Bayesian statistical model that penalizes phylogenetic inconsistencies to effectively separate the true evolutionary signal from technical artifacts. Benchmarking on both simulated datasets and multiple ground-truth datasets demonstrates that PhyloSOLID achieves superior lineage reconstruction accuracy over existing methods, for both single-cell RNA-seq and DNA-seq data. Additionally, a user-friendly web interface enables customized quality assessment, artifact removal, and interpretation of lineage structures. PhyloSOLID provides a powerful solution for decoding cellular evolution in developmental and disease contexts.

bioinformatics↗

bioRxiv2026

Unravelling genome-wide mosaic microsatellite mutations at single-cell resolution

Short tandem repeats (STRs), or microsatellites, are highly mutable genomic elements that modulate gene regulations and are implicated in a range of human diseases. However, detecting mosaic STR mutations at single-cell resolution remains challenging due to both technical and biological complexities. To address this, we developed BayesMonSTR, a robust algorithm that enables accurate detection of mosaic STR mutations. Using this tool in single-cell analysis of human tissues, we reveal an accumulation of longer mosaic STR insertions and deletions (indels) in aging mitotic and post-mitotic cells. Strikingly, prefrontal cortex (PFC) neurons accumulate a higher burden of STR mutations than B cells or lung epithelium, with aged neurons exhibiting a particularly pronounced increase in longer STR deletions. These mutations are enriched at transcription start sites (TSSs) and active enhancers of highly expressed genes. Our work establishes a foundation for genome-wide, hypothesis-free discovery of disease-associated mosaic STR mutations and reveals a previously unexplored landscape of mosaic STR variation in development and aging.

bioinformatics↗

bioRxiv2026

RVPSD: A comprehensive and user-friendly web database for RNA viral protein structures

Protein structures are central to understanding the diversity and biological function of RNA viruses. However, few experimentally validated structures of RNA viruses are currently available. To address this gap, we established the RNA Viral Protein Structure Database (RVPSD) that comprises diverse RNA viral protein structures predicted using AlphaFold2. RVPSD integrates taxonomic classification, viral nucleotide and protein sequences, functional annotations, and predicted three-dimensional protein structures to support a systematic exploration of the RNA viral proteomes. Currently, RVPSD comprises a total of 154,716 AlphaFold2-predicted RNA viral protein structures from 5,263 RNA virus species, with 84.9% exhibiting high pLDDT scores (>70) and representing a large-scale and comprehensive resource for RNA viral protein structures. RVPSD also provides a user-friendly web interface, with advanced search, sequence- and structure-based retrieval, interactive 3D visualization, and access and downloading structural data, enabling researchers to perform comparative structural analyses and functional annotation of viral "dark matter".

microbiology↗

bioRxiv2026

Ophiuchus-Ab: A Versatile Generative Foundation Model for Advanced Antibody-Based Immunotherapy

Antibodies exhibit extraordinary specificity and diversity in antigen recognition and have become a central class of therapeutics across a wide range of diseases. Despite this clinical success, antibody design remains fundamentally challenging. Antibody function emerges from intricate and highly coupled interactions between heavy and light chains, which complicate sequence-function relationships and limit the rational design of developable antibodies. Here, we reveal that modeling antibody sequence space at the level of paired heavy and light chains is essential to faithfully capture inter-chain dependencies, enabling a deeper understanding of antibody function and facilitating antibody discovery. We present Ophiuchus-Ab, a generative foundation model pre-trained on largescale paired antibody repertoires within a diffusion language modeling framework, unifying antibody generation and representation learning in a single probabilistic formulation. This framework excels diverse antibody design tasks, including CDR infilling, antibody humanization, and light-chain pairing. Beyond generation, diffusion-based pre-training yields transferable representations that enable accurate prediction of antibody properties, including developability, binding affinity, and specificity, even in low-data regimes. Together, these results establish Ophiuchus-Ab as a versatile foundation model for modeling antibodies, providing a foundation for next-generation antibody-based immunotherapy.

bioinformatics↗

bioRxiv2026

Rewiring vascular patterning through translational control in Arabidopsis

Plant vascular systems exhibit a wide developmental spectrum, from rigid woody tissues to soft, fleshy storage tissues. We show that increasing polyamine thermospermine transport into wild-type rootstocks, together with cytokinin, reprograms xylem identity from woody to fleshy in Arabidopsis. Our findings establish thermospermine as a mobile developmental signal and suggest a strategy for engineering plant vascular architecture.

plant biology↗

bioRxiv2026

Targeted mutagenesis in Ehrlichia canis deleting the phage head-to-tail connector protein gene and its assessment as a vaccine candidate preventing canine ehrlichiosis

Ehrlichia canis is primarily a Rhipicephalus sanguineus tick-borne rickettsial pathogen initially identified as causing canine monocytic ehrlichiosis, and infections in people have also been reported in Venezuela, Mexico, and parts of Europe. It is of high importance to have a vaccine suitable in protecting the canine host, which will aid in lessening E. canis infections also in people. Gene inactivation mutations in the phage head-to-tail connector protein genes (phtcp) from E. chaffeensis and A. marginale caused attenuated growth, and prior infection with the mutated bacteria induced protective immunity against wild-type bacterial infections in natural hosts, independent of blood-borne infection or tick-transmission infection. In the current study, we describe the development of targeted mutagenesis for the first time in E. canis genome and with a novel modification to avoid introducing antibiotic resistance cassettes to delete the phtcp ortholog from E. canis. The mutated E. canis was then assessed for its in vivo growth and the induction of host immunity exerted following the mutant infection aiding to protect against wild-type infection challenge in the canine host. We assessed systemic pathogen loads, hematological parameters, IgG immune responses, and plasma cytokines following the mutant infection relative to uninfected dogs. Similarly, the assessments were carried out following wild-type pathogen infections in dogs with or without prior mutant infection challenges. The study demonstrates that prior infection of dogs with the mutant induces immunity to prevent infection establishment by wild-type E. canis. Similarly, the mutant infection resulted in clear biological differences compared to the wild-type infection. This study establishes that the molecular genetic methods are broadly applicable to pathogens belonging to the family Anaplasmataceae and that the modified live vaccines with phtcp gene orthologs are valuable in reducing the diseases caused by the tick-borne rickettsial pathogens belong to Anaplasmataceae, including E. canis.

microbiology↗

bioRxiv2026

Functional In-Context Learning in Genomic Language Models with Nucleotide-Level Supervision and Genome Compression

AO_SCPLOWBSTRACTC_SCPLOWGenomic foundation models aim to learn general-purpose representations directly from DNA sequence, enabling sequence understanding, generation, and probabilistic reasoning across a wide range of biological tasks. Scaling such models to genomic lengths, however, remains challenging due to the tension between long-range context, nucleotide-level resolution, and practical computational efficiency. Architectural innovations have enabled increasingly long nominal inputs, but often struggle to translate additional context into meaningful performance gains, particularly in the presence of sparse functional signal along eukaryotic genomes. In this work, we revisit the design of long-context genomic foundation models from the perspective of training objective and data construction. We introduce Factorized Nucleotide Supervision (FNS), which reconciles efficient k-mer tokenization with single-nucleotide likelihoods through probability marginalization, and Genome Compression Pretraining (GCP), which reshapes the training distribution by concentrating on gene-centric and regulatory regions. Together, these techniques enable standard transformer-based models to perform functional in-context learning without sacrificing nucleotide-level fidelity or computational efficiency. Building on these ideas, we present a family of autoregressive genomic foundation models supporting contexts of up to 98k base pairs across eukaryotic and prokaryotic genomes. Across training-free evaluations and downstream fine-tuning benchmarks, our models consistently improve over prior approaches and match or exceed state-of-the-art baselines while enabling substantially more efficient inference. Together, these results demonstrate that aligning supervision and data regimes with the biological structure of genomic sequence provides a principled and effective path toward scalable and biologically faithful genomic language modeling. Models, data, and scripts for downstream analyses are publicly available at https://huggingface.co/GenerTeam.

genomics↗

bioRxiv2026

Pan-genome and multi-omics analyses reveal the genomic basis of symbiotic evolution in the mycoheterotrophic medicinal orchid Gastrodia elata

Mycoheterotrophy represents an extreme evolutionary strategy in which plants abandon photosynthesis and become obligately dependent on fungal partners for carbon and nutrients. Gastrodia elata, a medicinal orchid forming long-term symbioses with Armillaria and Mycena, provides a compelling system to investigate the genomic basis of obligate plant-fungus mutualism. Here, we generate a chromosome-level genome assembly (1.09 Gb) of a dark-red G. elata accession and construct a pan-genome from 12 Gastrodia accessions to dissect the evolutionary consequences of mycoheterotrophy. Phylogenomic analyses reveal pervasive hybridization across cultivated germplasm and demonstrate that tuber morphology more accurately reflects intraspecific relationships than stem color, challenging the traditional color-based taxonomy. Comparative genomic analyses reveal a pronounced degeneration of photosynthetic capacity. We detect no intact nuclear-encoded rbcS loci, which would preclude assembly of the Rubisco holoenzyme and thus canonical Calvin-Benson carbon fixation. Notably, a subset of photosynthesis-related genes is retained and transcriptionally active, suggesting their co-option into non-photosynthetic regulatory roles. Despite millions of years of intimate association with fungal partners, we detect no evidence of fungal-derived horizontal gene transfer based on a multi-step phylogenomic validation pipeline, indicating that G. elata-fungus mutualism is sustained through metabolic exchange rather than genetic integration. We further identify the Gastrodia antifungal protein (GAFP) gene family as a key molecular innovation underlying symbiotic homeostasis. The recently derived Class 1 GAFP lineage exhibits distinct domain architecture, tandem expansion, and elevated expression, consistent with enhanced regulation of fungal overgrowth. Finally, we delineate a specialized nutrient-acquisition framework adapted to obligate heterotrophy, in which fungal trehalose hydrolysis supplies hexose carbon via an expanded sugar transporter protein (STP) repertoire, while organic nitrogen is assimilated through amino acid and oligopeptide transporters coupled with urease-mediated conversion, compensating for the loss of nitrate uptake and reduction pathways. Together, these results establish a pan-genomic blueprint for symbiotic adaptation and reductive genome evolution in G. elata.

genomics↗

bioRxiv2026

Proteomic composition and mutual assembly of the C2a projection in vertebrate motile cilia

The central apparatus of motile cilia, consisting of central microtubules and various protein projections, is essential for dictating the ciliary movement. Although three proteins (FAP65, FAP147, and FAP70) have been localized to the C2a projection in Chlamydomonas reinhardtii, the full protein composition and functional roles of the vertebrate C2a remain inadequately defined. Here, we use three knockout mouse models corresponding to their respective homologs (Ccdc108, Mycbpap, and Cfap70) to systematically investigate their functions in vertebrates. Notably, all three knockout strains exhibit distinct phenotypes related to primary ciliary dyskinesia (PCD), including hydrocephalus and sinusitis. The ciliary incorporation of CCDC108, MYCBPAP, and CFAP70 is essential for one anothers stability, with the loss of any single component triggering C2a collapse, which destabilizes the central pair microtubules and ultimately alters the ciliary movement pattern. Furthermore, we significantly expand the vertebrate C2a proteome by identifying ARMC3 and MYCBP as additional C2a components. Collectively, our findings illuminate the proteomic composition and strict physiological requirements of the vertebrate C2a projection, providing new insights into the molecular pathogenesis of PCD. Impact StatementDeficiency in any of the interdependent C2a proteins (CCDC108, MYCBPAP, and CFAP70) collapses this central pair microtubule-associated projection, disrupting vertebrate ciliary movement and causing primary ciliary dyskinesia phenotypes in mice.

cell biology↗

bioRxiv2026

The ZmHEAT1/ZmKAKU42-ZmNCH1 module regulates heat stress tolerance by modulating nuclear envelope structure in maize

Heat stress threatens maize production. Through a genome-wide association study using pollen viability decline rate as a phenotype, we identified ZmHEAT1, encoding the nuclear envelope protein ZmKAKU41, as a key regulator of thermotolerance. ZmHEAT1 positively regulates heat tolerance at seedling and reproductive stages, with its overexpression improving thermotolerance and its knockout reducing pollen viability and yield under high temperatures. ZmHEAT1 interacts with its homolog ZmKAKU42 and the nucleoskeleton protein ZmNCH1 to form a complex at the nuclear envelope. Mutants lacking ZmHEAT1 or ZmKAKU42 exhibit increased nuclear envelope damage under heat stress, along with repressed expression of key heat shock protein genes (e.g., HSP90-2, HSP17.4). This work establishes the ZmHEAT1/ZmKAKU42-ZmNCH1 complex as a critical guardian of nuclear integrity and heat response, providing a valuable genetic resource for breeding heat-tolerant maize varieties. One-sentence summaryModulation of the nuclear envelope structure in maize is involved in heat stress tolerance.

molecular biology↗

bioRxiv2026

Histology-Aware Graph for Modeling Intercellular Communication in Spatial Transcriptomics

Cell-cell communication (CCC) is essential to how life forms and functions. Recent tools achieve single-cell-resolved CCC inference utilizing spatial transcriptomics (ST). However, most ignore the modeling of tissue contexts surrounding cells, causing high false-positive/negative rates. Here, we propose HARMONIC, a CCC inference method integrating multimodal ST and hematoxylin and eosin (H&E)-stained images. HARMONIC causally modeling the transcriptomic-to-contextual relationships for CCC inference. The state-of-the-art performance was verified across ST platforms, species and healthy/diseased status, on both synthetic and biological samples. HARMONIC was applied in various real-world scenarios, especially on tissues with clear morphological boundaries, including cortical layers in mouse brain, medullary-cortex structures in mouse kidney, as well as tumor-stromal/immune interface. Significant refinement of false-positive/negative predictions was observed compared to ST-only CCC tools.

bioinformatics↗

bioRxiv2026

DNA synthesis inside the hepatitis B virus creates a high-energy spool

The Hepatitis B Virus (HBV) capsid assembles around an RNA pregenome which is reverse-transcribed into double-stranded DNA. It remains unclear how this DNA, which is stiff, bulky, and has significant negative charge, is accommodated within the capsid. The organization of the genome will answer this and lend insight into the viral reverse transcription reaction. We determined the structures of mature HBV and Duck HBV, finding that the DNA forms a spool that is coaxial with the capsids fivefold symmetry and interacts with charges on the capsid interior. We calculate that the energy of DNA bending would create a metastable capsid that just awaits a trigger for DNA release. Thus, we see how nature has created a fragile energy minimum that enables genome uncoating.

microbiology↗

bioRxiv2026

THIK-1 channel mediates microglial glucose sensing and modulates AgRP neurons

Microglia play essential roles in maintaining energy homeostasis, and their dysfunction contributes to metabolic disease. Although high-fat diet (HFD) exposure induces microglial activation, the underlying mechanisms remain poorly defined. Here, we identified a previously unrecognized role for THIK-1 channel in mediating glucose sensing of microglia in arcuate nucleus of the hypothalamus (ARH), during HFD-induced obesity. Pharmacological inhibition of THIK-1 channel with tetrapentylammonium (TPA) suppresses feeding and attenuates body-weight gain in diet induced obese mice. Mechanistically, inhibition of agouti-related peptide (AgRP) neurons is indispensable for TPA-induced hypophagia. Moreover, THIK-1 inhibition promotes microglial phagocytosis of perineuronal nets (PNNs), leading to reduced AgRP neuronal activity and feeding suppression. Together, these findings establish THIK-1 as a critical glucose sensor in hypothalamic microglia and uncover a microglia-dependent pathway through which overnutrition modulates AgRP neuronal activity via PNN remodeling to regulate energy balance, highlighting THIK-1 as a potential therapeutic target for treatment of diet-induced obesity.

neuroscience↗

bioRxiv2026

Extending Conformational Ensemble Prediction to Multidomain Proteins and Protein Complex

Proteins execute cellular functions through a structural continuum ranging from stable, folded domains to highly dynamic intrinsically disordered regions (IDRs). Conformational ensembles represent the set of three-dimensional structures a protein adopts under a specific set of conditions, and underlie essential processes from catalysis to complex signaling networks. While deep learning has revolutionized structure prediction, capturing the distinct conformational diversity of folded and disordered regions--especially within multidomain proteins and large assemblies--remains a fundamental challenge. Here we introduce IDPFold2, a generative framework that models the heterogenous protein thermodynamics by integrating a Mixture-of-Experts architecture into the flow matching framework. By routing residues from different regions to specialized expert networks, IDPFold2 accurately predicts conformational ensembles for folded domains, IDRs and multidomain proteins. IDPFold2 outperforms state-of-the-art methods in capturing key functional states and fitting the experimental observations across local and global scales. Furthermore, we describe an extension of IDPFold2 to protein assemblies, deciphering the complex binding modes of IDRs within large macromolecular complexes, providing a generalizable tool for exploring the dynamic proteome.

bioinformatics↗

bioRxiv2026

Microglial Lag3 Drives α-Synuclein--induced Neurotoxic Activated (A1) Astrocytes and Neurodegeneration

BackgroundNeuroinflammation and pathologic -synuclein (-syn) aggregation cooperate to drive dopaminergic neurodegeneration in Parkinsons disease, but the glial receptors that couple extracellular -syn to inflammatory cascades remain incompletely defined. Microglia express higher levels of lymphocyte activation gene 3 (Lag3) than neurons, yet the contribution of microglial Lag3 to -syn recognition, glial crosstalk, and neurodegeneration is unknown. MethodsBiochemical binding assays, live-cell imaging, cytokine profiling, and neuron-microglia-astrocyte co-culture paradigms were used to define Lag3-dependent -syn preformed fibril (PFF) binding, uptake, and microglial activation. To interrogate in vivo function, microglia-specific Lag3 conditional knockout mice (Lag3L/L-Cx3cr1CreER) and littermate controls received unilateral intrastriatal -syn PFF injections, followed by histological, biochemical, and behavioral assessments of -syn pathology, gliosis, nigrostriatal integrity, and motor performance. Results-syn PFFs bound microglial Lag3 with high specificity and nanomolar affinity and required Lag3 for efficient fibril internalization and induction of proinflammatory cytokines. Microglial Lag3 deficiency markedly blunted -syn PFF-evoked microglial activation, prevented cytokine-driven conversion of astrocytes into neurotoxic reactive A1 astrocytes, and abolished astrocyte-dependent neuronal death in vitro. In vivo, microglia-specific Lag3 deletion reduced cortical, striatal, and substantia nigra pS129 -syn pathology, suppressed microgliosis and A1 astrocyte induction, preserved substantia nigra dopaminergic neurons and striatal dopamine transporter/tyrosine hydroxylase expression, and ameliorated -syn PFF-induced motor deficits. ConclusionsThis study identifies microglial Lag3 as a key receptor linking extracellular -syn PFF recognition to inflammatory amplification, neurotoxic reactive A1 astrocyte conversion, and dopaminergic neurodegeneration. Together with prior work on neuronal Lag3, these findings support a cell-type-specific dual-axis model in which neuronal Lag3 mediates -syn propagation while microglial Lag3 drives glia-dependent neurotoxicity, positioning Lag3 as a promising precision therapeutic target in -synucleinopathies.

neuroscience↗