Biology subjects

Liu, H.

Publications and source records attributed to Liu, H..

At least 127 records · Page 7Linked to original sources

bioRxiv2026

Exploration of Orally Disintegrating Tablet for Sublingual Vaccination against Mucosal Bacterial Infection

Oral mucosal bacterial infections impose a substantial global disease burden, yet current clinical management typically reduces microbial load only transiently and rarely establishes durable protection at the oral surface. Analysis of 200 patients with periodontitis revealed that elevated levels of pathogen-specific salivary secretory Immunoglobulin A (sIgA) were strongly associated with reduced bacterial burden and improved clinical periodontal outcomes, identifying sIgA as a key determinant of effective oral protection. Guided by this observation, we developed a sublingual, orally disintegrating tablet vaccine (Capot) that incorporates bacterial extracellular vesicles providing a comprehensive repertoire of native antigens and multiple pathogen-associated molecular patterns, encapsulated within a calcium phosphate nanoshell to enable safe transmucosal delivery to submandibular lymph nodes. The rapidly disintegrating tablet format minimizes inadvertent swallowing and enhances local mucosal bioavailability. In mice and non-human primates, Capot induced robust and long-lasting salivary sIgA responses without overt oral mucosal or gastrointestinal inflammation and conferred strong protection against primary, recurrent, and antibiotic-resistant periodontitis. Together, these findings establish sublingual tablet vaccination as a practical strategy for selectively engaging oral mucosal immunity and preventing chronic bacterial diseases at oral mucosal surfaces.

bioengineering↗

bioRxiv2026

Lysosomal Expansion Compartments Mediate Zinc and Copper Homeostasis in Caenorhabditis elegans

Zinc is an essential transition metal that participates in many biological processes. In C. elegans, excess zinc is stored in lysosomes in intestinal cells; this process involves increasing the expression of the zinc transporter CDF-2 and remodeling of lysosomes characterized by an increase in the volume of the expansion compartment. To determine if this is a more general property, we investigated other metals. Here we report that lysosomes are remodeled in response to excess copper, manganese, and cadmium, with each metal causing an increase in the volume of the expansion compartment. Mutants with a reduced number of lysosomes were hypersensitive to growth retardation caused by excess copper and manganese, suggesting metal toxicity is prevented by metal sequestration in lysosomes. Using a novel method to analyze isolated lysosomes by X-ray Fluorescence Microscopy we demonstrated that zinc, copper and manganese are detectable in the lumen of lysosomes. To further analyze copper, we examined localization of CUA-1.1, a copper transporter that moves copper into the lumen of lysosomes. Like the zinc transporter CDF-2, CUA-1.1 localizes to both the acidified and expansion compartments in excess copper. These results indicate that the same intestinal lysosomes store zinc, copper and manganese. Lysosome remodeling characterized by an increase in volume of the expansion compartment is not specific to zinc but is a more general phenomenon during metal storage in lysosomes.

molecular biology↗

bioRxiv2026

c-Fos enhances influenza virus replication by stabilizing the M2 protein and promoting autophagosome accumulation

The influenza A virus (IAV) employs multiple strategies to hijack host cellular machinery for efficient replication. While autophagosome accumulation is known to promote IAV replication, and the viral matrix protein 2 (M2) ion channel protein plays essential roles in viral uncoating, assembly, and autophagy induction, the mechanisms regulating M2 stability remain incompletely understood. Furthermore, although c-Fos participates in the replication of various viruses, its function in IAV infection has not been characterized. Here, we identify c-Fos as a critical proviral host factor that enhances IAV replication through stabilizing M2 protein and promoting autophagosome accumulation. We demonstrate that IAV infection triggers M2-mediated cytosolic calcium elevation, which upregulates c-Fos expression. The induced c-Fos physically interacts with M2 and prevents its proteasome and lysosomal degradation, thereby increasing M2 accumulation. This stabilized M2 protein as a viral protein directly facilitates viral replication while simultaneously promoting autophagosome accumulation to further enhance the process. Our findings reveal a novel positive feedback loop in IAV infection, establishing c-Fos as a key regulator of IAV replication through M2 stabilization, and highlighting these interactions as potential therapeutic targets for antiviral intervention. IMPORTANCEInfluenza A virus (IAV) remains a significant global health threat, causing substantial morbidity and mortality. Understanding virus-host interactions is crucial for developing antiviral strategies. Here, we uncover a previously unrecognized positive feedback loop in which IAV exploits the host transcription factor c-Fos to enhance its own replication. We demonstrate that IAV infection upregulates c-Fos through M2-mediated calcium signaling, and the induced c-Fos in turn stabilizes the viral M2 protein. This stabilized M2 not only directly supports viral replication but also promotes autophagosome accumulation, further facilitating virus production. Our findings establish c-Fos as a critical proviral host factor and reveal a mechanism by which IAV hijacks host cellular machinery to create a favorable environment for efficient replication. The identification of this c-Fos-M2 axis not only advances our understanding of IAV-host interactions but also opens new avenues for therapeutic intervention targeting this vulnerability in the viral life cycle.

cell biology↗

bioRxiv2026

Stage-adaptive integration of polydopamine promotes hPSC-derived alveolar organoids differentiation and maturation

Human pluripotent stem cell (hPSC)-derived alveolar organoids (ALOs) have emerged as a powerful tool for modeling human lung development and disease, and accelerating respiratory drug discovery. However, achieving the functional maturation of ALOs remains challenging. Polydopamine (PDA) is a mussel-inspired polyphenolic biomaterial with antioxidant and adhesive properties that can be deployed as surface coatings and nanoparticles (NPs) in cell culture systems. Here, we integrate PDA coatings and NPs sequentially in a stage-adaptive manner throughout the hPSC-derived ALOs differentiation system and study their contributions to ALOs maturation. Our results demonstrated PDA coating yielded more anterior foregut endoderm (AFE) spheroids by strengthening the interaction between Matrigel and substrate. Bulk RNA-seq revealed enrichment of cell-cell and cell-extracellular matrix interactions by PDA. The subsequent incorporation of PDA NPs in Matrigel at lung progenitor cells (LPCs) stage significantly mitigated reactive oxygen species (ROS) accumulation and enhanced LPCs generation. Functionally, AT2 cells in ALOs exhibit characteristic lysosome-to-lamellar body (LB) maturation due to the traffic of internalized PDA NPs to endolysosome. Transcriptomics further indicated enrichment of endocytic-phagosome and epithelium development pathways by PDA treatment. Together, our study establishes a stage-adaptive-integrated PDA strategy throughout hPSC-to-ALOs differentiation and demonstrates that PDA robustly enhances ALOs maturation and secretory function. Graphic abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=178 SRC="FIGDIR/small/708928v1_ufig1.gif" ALT="Figure 1"> View larger version (50K): org.highwire.dtl.DTLVardef@88208dorg.highwire.dtl.DTLVardef@1111590org.highwire.dtl.DTLVardef@9ea9b0org.highwire.dtl.DTLVardef@969fad_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

bioRxiv2026

Ligand-guided Sequence-structure Co-design of De Novo Functional Enzymes

Proteins underpin essential biological functions across all kingdoms of life. The capacity to design novel proteins with tailored activities holds transformative potential for biotechnology, medicine, and sustainability. However, since protein functions, particularly enzymatic activities, depend on precise interactions with small-molecule ligands, accurately modeling these interactions remains a formidable challenge in de novo protein design. Here, we introduce EnzyGen2, a protein foundation model designed for the simultaneous co-design of sequence and structure under ligand-guided functional targeting. Comprising 730 million parameters, EnzyGen2 is trained on 720,993 protein-ligand pairs using multi-task learning objectives that encompass joint prediction of sequence, structure, and protein-ligand interactions. In rigorous in silico benchmarks, EnzyGen2 consistently outperforms state-of-the-art baselines, including Inpainting, RFdiffusion/ProteinMPNN, RFdiffusion2/LigandMPNN, and RFdiffusion3/LigandMPNN, as measured by the enzyme-substrate prediction score, AlphaFold2 confidence metric, and structural fidelity, while it generates samples 400x faster than prior methods. We further experimentally validated EnzyGen2 across multiple enzyme families, including chloramphenicol acetyltransferase, aminoglycoside adenylyltransferase, and thiopurine S-methyltransferase. De novo enzymes generated by our family-specific EnzyGen2 exhibited catalytic activities comparable to or exceeding those of natural enzymes, while retaining substantial novelty with sequence identities as low as 51.6%. These results establish EnzyGen2 as a robust Artificial Intelligence-based tool for functional enzyme design, demonstrating the power of large protein foundation models to create high-performance, novel biocatalysts.

bioinformatics↗

bioRxiv2026

Targeting CPSF73, the mRNA 3' End Processing Endonuclease, Moves Cancer Cells Away from the Mesenchymal State

BackgroundMetastasis significantly contributes to cancer-related mortality and therapeutic failure. Cancer cells acquire metastatic potential by losing epithelial characteristics and gaining mesenchymal properties through the epithelial-mesenchymal transition (EMT). Differential poly(A) site (PAS) usage, known as alternative polyadenylation (APA), generates mRNA isoforms differing in coding sequence, subcellular localization, stability, or translation efficiency. In cancer, 3'UTR shortening increases expression of proto-oncogenes by escaping miRNA-mediated repression. High expression of CPSF73, which cleaves mRNA precursors at PASs, is associated with unfavorable prognoses in cancer patients. However, the role of APA in regulating EMT remains poorly understood. MethodsIn this study, to investigate the role of APA in EMT, we employed JTE-607, a small-molecule inhibitor of CPSF73 activity, to examine the impact of catalytic inhibition of CPSF73 on proliferation and EMT in MDA-MB-231, MCF7, A549, and HepG2 cancer cells. To identify differential usage of PASs, global profiling of APA changes, and differential gene expression analysis were performed in MDA-MB-231 cells. Additionally, antisense oligonucleotides were used to block the use of a specific PAS whose APA change may be a driver of EMT reversal. ResultsOur findings showed that catalytic inhibition of CPSF73 not only attenuates cancer cell proliferation but also moves the cells away from the mesenchymal state across all four cell lines tested. Global profiling of APA changes following CPSF73 inhibition revealed widespread 3'UTR lengthening and suppression of intronic PASs in MDA-MB-231 cells. APA shifts were observed in key EMT-related genes, accompanied by decreased expression of corresponding proteins across all four cell lines. We used antisense morpholino oligonucleotides to block the proximal PAS of AKT2, shifting the balance of AKT2 mRNA isoforms toward the long isoform. This shift caused EMT reversal, marked by reduced AKT2 protein expression, changes in EMT-related markers, and impaired invasion by MDA-MB-231 cells. ConclusionTogether, these findings identify APA-mediated 3UTR lengthening, with functional consequences in EMT-related genes, as a coordinated mechanism leading to an attenuated EMT phenotype, highlighting a significant connection between APA and the EMT process. Interfering with these APA changes may offer a promising therapeutic strategy to suppress metastasis, with potential efficacy across multiple pathways. Statement of SignificanceOur findings highlight APA-mediated 3 UTR lengthening as a coordinated mechanism that promotes EMT reversal and support CPSF73 inhibition or APA-targeting strategies as potential therapeutic approaches to suppress metastasis across multiple pathways.

cancer biology↗

bioRxiv2026

ALKBH5 Promotes Hepatic Gluconeogenesis via m6A-mediated Stabilization of Ogt mRNA

Excessive hepatic glucose production is a hallmark of fasting hyperglycemia in type 2 diabetes mellitus, yet the epitranscriptomic mechanisms that sustain this dysregulation remain incompletely understood. Here, we show that dexamethasone/forskolin-induced gluconeogenic activation triggers widespread remodeling of RNA m6A methylation in mouse primary hepatocytes. Among the m6A regulators examined, the demethylase ALKBH5 is robustly induced both in vitro and in fasted livers. This induction is mediated by the glucocorticoid receptor, which binds to the Alkbh5 promoter and activates its transcription. Functionally, ALKBH5 overexpression enhances gluconeogenic gene expression and glucose production, whereas both global and hepatocyte-specific Alkbh5 knockout mice exhibit suppressed hepatic gluconeogenesis. Mechanistically, we identify Ogt as a primary downstream target, defining an ALKBH5-OGT epitranscriptomic axis in hepatocytes. ALKBH5 demethylates and stabilizes Ogt mRNA, thereby elevating OGT expression and promoting gluconeogenic gene expression. Consistently, the pro-gluconeogenic effects of ALKBH5 are largely abrogated by OGT knockdown. Finally, pharmacological inhibition of ALKBH5 with 18l effectively improves glucose tolerance and suppresses hepatic gluconeogenesis in both wild-type and db/db mice. Together, these findings reveal a glucocorticoid-responsive epitranscriptomic mechanism whereby ALKBH5 stabilizes Ogt mRNA to drive gluconeogenesis and highlight ALKBH5 as a promising therapeutic target for type 2 diabetes mellitus.

molecular biology↗

bioRxiv2026

Diet- and metabolic state-dependent remodeling of the mouse brain lipidome

The hypothalamus and brainstem are key hubs of metabolic control that undergo dynamic molecular adaptations in response to changes in energy availability. This remodeling is associated with changes in the expression and activity of enzymes linked to energy homeostasis but also importantly, lipid metabolism. Given that lipids account for [~]50% of the brains dry weight, it is likely that lipid metabolism is a major determinant of brain function. Therefore, understanding how the hypothalamic and brainstem lipidome adapts to metabolic perturbation is key to understanding tissue function and metabolic health. Here we characterize the remodeling of [~]750 lipid species in mouse hypothalamus and brainstem, as well as the cerebrospinal fluid and plasma, in response to a metabolic challenge (an Ad Libitum-Fasting-Refeeding cycle). We show that around 45% and 36% of lipids in the hypothalamus and brainstem respectively, exhibit reversible, nutritional state-dependent remodeling during this metabolic challenge, and that this remodeling is substantially impacted by long-term high fat diet intervention. Of note, targeted analysis of specific lipids revealed that certain fatty acids were affected by this intervention in the hypothalamus and brainstem, most strikingly defined by the reversible fasting-induced increase in linoleic acid (18:2)-containing phosphatidylcholines in both the hypothalamus and brainstem, an effect that is abolished by high fat diet intervention. Such precise and intervention-specific regulation of linoleic acid (18:2)-containing phosphatidylcholines provides a previously unrecognized role for this lipid in the physiological response to fasting. Thus, these findings demonstrate that the brain lipidome undergoes robust, nutritional state-dependent remodeling, and provide a comprehensive resource for investigating its role in regulating metabolic adaptations.

physiology↗

bioRxiv2026

Sex-specific Genetic Regulatory Effects in Chickens

Sexual dimorphism is a defining vertebrate feature, yet its sex-specific molecular architecture remains poorly understood. Here we established a sex-balanced, uniformly reared chicken cohort to map this landscape, integrating individual whole-genome sequencing with 7,969 bulk and 779,380 single nucleus transcriptomes across 32 tissues from 280 birds. We identified 495,098 independent expression quantitative trait loci for 20,194 genes, including 10,937 loci modulated by cell-type composition. Notably, 340 genes were regulated by 449 loci in a sex-dependent manner, significantly enrichment in endocrine tissues like adipose and the adrenal gland. Furthermore, we fine-mapped 1,219 structural variants, demonstrating their unique roles to tissue- and sex-specific expression beyond SNPs. Ultimately, we showed the utility of these regulatory effects in elucidating the molecular basis of metabolism and complex traits in both chickens and humans. This comprehensive atlas of regulatory effects provides profound insights into the genomic and molecular basis of sexual dimorphism in vertebrates.

genomics↗

bioRxiv2026

Information Geometry Reconciles Discrete and Continuous Variation in Single-Cell and Spatial Transcriptomic Analysis

Single-cell and spatial transcriptomics provide high-resolution cellular characterization, yet standard analytical approaches remain theoretically misaligned with the probabilistic nature of the data. After UMI normalization, current pipelines rely on Euclidean or log-transformed Euclidean distance for similarity measurement. Both are fundamentally ill-suited to model the multinomial count data. Euclidean distance in normalized space overemphasizes high-variance genes, while log-transformation inverts this bias but at the cost of distorting subtle, continuous expression modulations. Neither approach naturally captures the dual nature of gene expression: both discrete presence/absence transitions and continuous quantitative variation. To overcome these limitations, we introduce GAIA (Geometric Analysis from an Information Aspect), an information-geometric framework for cell representation learning and inter-cell similarity measurement. By anchoring analysis in the true probabilistic model, treating cells as multinomial distributions over genes and projecting cells to a statistical manifold, GAIA organically reconciles both the presence/absence effect and the more continuous expression modulations. Mathematically, GAIA exploits the equivalence between Fisher-Rao distance in multinomial space and geodesic distance on the unit hypersphere, a property that enables both theoretical guarantees and computational efficiency. Experiments in synthetic and real scRNA-seq and spatial transcriptomic datasets demonstrate that GAIA preserves robust and consistent cell-to-cell relationships, delineates biologically nuanced sub-types, mitigates batch effects arising from sequencing depth variation, and eliminates the dependence on knowledge-restricted gene selection for learning meaningful cell representations. Overall, GAIA offers a knowledge-lean, variance-stabilizing framework for analyzing single-cell and spatial transcriptomic data, enhancing discrimination between nuanced cell sub-type and -states.

bioinformatics↗

bioRxiv2026

Zinc excess promotes lysosome remodeling by activating HLH-30/TFEB through the action of the high zinc sensor HIZR-1.

Zinc is an essential element that plays many roles in animals. Since excess zinc is toxic, animals have evolved sophisticated mechanisms to achieve homeostasis. A conserved mechanism is to store excess zinc in specialized lysosomes, which contributes to zinc detoxification and provides a supply when zinc becomes limiting. In C. elegans excess zinc conditions promote an increase in lysosome-related organelles called bilobed granules. Defining how zinc-regulated transcription drives the observed lysosome remodeling is key to understanding zinc homeostasis processes. Here we describe a positively regulated zinc cascade controlled by hizr-1 and hlh-30/TFEB, which encode the C. elegans high zinc sensor and the master regulator of the autophagy-lysosomal pathway, respectively; essential for connecting excess zinc homeostasis to lysosome biogenesis and remodeling. Our transcriptomic, genetic, and bioinformatic studies indicate that hizr-1 and hlh-30 are necessary and sufficient to activate transcription of lysosome genes under excess zinc conditions. In our regulatory model, zinc binding activates HIZR-1 protein, which accumulates in the nucleus and activates genes containing the HZA enhancer, including hlh-30. HLH-30 protein accumulates in the nucleus and activates genes containing the E-box enhancer. Genetic analysis of loss-of-function mutants demonstrated that both hizr-1 and hlh-30 are necessary for animals to tolerate excess zinc. Furthermore, HLH-30 promotes the increase in the number of acidified compartments, whereas HIZR-1 promotes the increase in the volume of the expansion compartment. These results define a genetic pathway that responds to excess zinc by increasing the number of lysosome-related organelles and their capacity to store and detoxify cytosolic zinc.

genetics↗

bioRxiv2026

Biodegradable Intra-arterial Devices for Focal Drug Delivery to Targeted Organs

This study presents the development of biodegradable intra-arterial drug delivery (IADD) devices for the focal treatment of targeted organs. The IADD devices are fabricated using magnesium (Mg) and poly(glycerol sebacate) (PGS), leveraging their biocompatibility and tunable biodegradability, and are loaded with two model drugs, dexamethasone (DEX) or cisplatin (CIS). The IADD devices with helical and linear designs were fabricated for focal drug delivery to targeted organs and characterized for their microstructure and composition using scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), thermogravimetric analysis (TGA), and Fourier-transform infrared spectroscopy (FTIR). The results confirmed the successful incorporation and stability of the drugs within the device. The IADD devices demonstrated in vitro release of DEX and CIS over 30 days, with drug-dependent and fabrication-dependent release profiles. The IADD devices demonstrated cytocompatibility with endothelial cells and sustained pharmacological activity against glioma cells throughout the in vitro release period. DEX-loaded IADD devices were implanted into the artery upstream of a target organ in rat models. The devices implanted into the renal artery to target the kidney and the carotid artery to target the brain achieved 109-fold and 68-fold improvements, respectively, in organ vs systemic drug levels compared to oral drug administration. Arterial histology and explanted-device analysis provided preliminary evidence of local vascular tolerability and device integrity over the examined implantation period. Overall, these results support IADD devices as a proof-of-concept approach for focal intra-arterial drug delivery to targeted organs, demonstrating substantially elevated target-organ drug levels relative to systemic exposure. HighlightsO_LIIntroduction of a novel intra-arterial drug delivery (IADD) platform C_LIO_LIIADD devices were fabricated from bioresorbable Mg and drug-loaded PGS C_LIO_LIDEX- and CIS-loaded IADD devices were evaluated for in vitro release and bioactivity C_LIO_LIIADD delivery achieved marked DEX enrichment in the kidney and brain C_LIO_LIPost-implantation studies support preliminary vascular safety C_LI

bioengineering↗

bioRxiv2026

Interoceptive autonomic regulation in typical development and autism spectrum disorder: A computational model integrating multiple physiological systems

BackgroundInteroceptive cardiovascular signals, including heart rate (HR) and blood pressure (BP), arise from coordinated sympathetic (SNS) and parasympathetic (PSNS) regulation and contribute to affective and cognitive processes. Although atypical autonomic nervous system (ANS) modulation has been reported in autism spectrum disorder (ASD), the dynamical structure underlying branch-specific coordination remains insufficiently characterized. ObjectiveTo estimate latent ANS regulatory structure in typically developing (TD) and ASD individuals using a computational modeling framework. MethodsA closed-loop computational model integrating cardiovascular, respiratory, and autonomic dynamics was developed. ANS regulation was formalized using three autonomic control modes (coupled reciprocal, coupled nonreciprocal, and uncoupled) and parameterized by the relative activity of SNS and PSNS branches. HR and BP responses to the head-up tilt (HUT) test were simulated, and regulatory surfaces were compared with empirical HR and BP data from TD and ASD groups. Additional simulations under normal respiration, deep respiration, and absence of respiration evaluated mean arterial pressure (MAP) regulation across varying SNS-PSNS activity combinations. ResultsTD individuals exhibited differentiated SNS-PSNS coordination patterns across control modes, whereas ASD individuals showed convergence of relative SNS-PSNS activity. In TD, HR and BP distributions under coupled reciprocal mode were most consistent with expected physiological responses, characterized by high SNS and low PSNS activity during postural challenge. In ASD, empirical data extended toward regions of relatively higher PSNS weighting. Incorporation of deep respiration enhanced MAP reduction during BP recovery, particularly under over-elevated SNS activity. ConclusionThis study provides a mechanistic, state-space characterization of autonomic coordination in TD and ASD populations, enabling inference of latent autonomic regulation from measurable interoceptive phenotypes and identifying respiration as a model-based regulatory lever that augments cardiovascular stabilization.

neuroscience↗

bioRxiv2026

A novel TaNF-YC10-TaNF-YB1-TabHLH95 module coordinates starch biosynthesis in wheat endosperm

Wheat grain weight and flour quality largely depend on starch biosynthesis, yet the mechanisms by which transcription factors coordinate this process remain poorly understood. In this study, using an integrative strategy that combines genome-wide association analysis with yeast two-hybrid library screening, we identify TaNF-YC10, a Nuclear Factor Y transcription factor, as a positive regulator of starch accumulation in the wheat endosperm. Loss of TaNF-YC10 reduces starch content and alters starch granule size distribution, whereas overexpression enhances starch accumulation and increases grain weight. TaNF-YC10 binds and activates core starch biosynthetic-related genes, including AGPL1, GBSS1, YUC11, and NF-YB7, and forms higher-order transcriptional complexes with TaNF-YB1 and TabHLH95 to coordinate multiple regulatory pathways. TaNF-YC10-A1-Hap2 is associated with higher starch content and thousand grain weight and has been selected during wheat breeding in China. Collectively, our findings establish TaNF-YC10 as a pivotal transcriptional hub in starch regulation and highlight its potential as a target for genetic improvement of grain yield in wheat.

plant biology↗

bioRxiv2026

Minipoa: A minimizer-based method for fast and memory-efficient partial order alignment

Partial order alignment (POA) has emerged as a fundamental component in long-read error correction, assembly and pangenomics. However, conventional POA algorithms are limited by high time and memory requirements, making them inefficient for large-scale datasets. Here, we present minipoa, a fast and memory-efficient POA tool that incorporates seed-chain-align heuristics, adaptive or static banding strategies, and single-instruction multiple-data optimizations. Minipoa achieves up to a 5-fold speedup over abPOA, reduces memory usage by up to 16-fold, and improves correction accuracy, while maintaining strong performance on both PacBio and ONT simulated datasets, and can be readily integrated into existing long-read error correction and assembly workflows. In multiple sequence alignment datasets, minipoa demonstrates superior computational efficiency and alignment accuracy compared with all other tested tools, achieving Total Column scores up to 2.5-fold higher than MAFFT in low-similarity scenarios. Moreover, minipoa enables multiple sequence alignment of megabase-long genomes and million-sequence datasets, demonstrated by 342 Mycobacterium tuberculosis sequences and one million SARS-CoV-2 sequences respectively. Collectively, minipoa is well positioned to become a cornerstone in the era of large-scale pangenomics.

bioinformatics↗

bioRxiv2026

Unwinding of RNA G-quadruplexes induces mouse and human totipotency

Totipotent stem cells (TotiSCs) have significant application prospects in regenerative medicine and assisted reproductive technologies. The mRNAs of totipotency-related genes are rich in G-quadruplex (G4) structures, while the G4 density of pluripotency-related genes mRNAs is relatively low, suggesting a potential functional link between RNA G4s and the totipotent state. Nevertheless, how G4s are involved in the establishment or maintenance of mouse and human totipotency remains poorly understood. Here, we demonstrate that FC3, a small-molecule RNA G4 unwinder, enables efficient induction and maintenance of mouse and human TotiSCs (mG4TotiSCs and hG4TotiSCs). These FC3-induced TotiSCs closely recapitulate the molecular features of 2-cell-stage blastomeres via transcriptomic and epigenomic profiling. Functionally, both mG4TotiSCs and hG4TotiSCs exhibit totipotent capacity: they differentiate into embryonic and extraembryonic lineages in vitro and in chimeric embryos; moreover, they autonomously self-organize into blastocyst-like structures without exogenous signalling. Mechanistically, we identify that Gata2 mRNA, a G4-containing transcript, is essential for FC3-mediated reprogramming. Genetic disruption of Gata2 would abolish totipotency induction. Collectively, RNA G4 unwinding is a new regulatory axis governing totipotency acquisition and maintenance, providing insight into the functional interplay between nucleic acid secondary structures and cell fate plasticity.

cell biology↗

bioRxiv2026

MNS induces antiviral protection and suppresses inflammation

BackgroundIdentifying safe and broad-spectrum antiviral and anti-inflammatory agents remains an urgent need in infectious and inflammatory diseases. Here, we demonstrated that MNS (NSC170724), a small-molecule nitrovinyl benzodioxole, enhanced antiviral defense while limiting excessive inflammation. MethodsThe antiviral activity of MNS was evaluated in multiple cell lines and mouse infection models across DNA and RNA viruses. Virus-induced and LPS-induced inflammatory responses were assessed using RT-qPCR, ELISA and western blotting. Bulk RNA-seq and ATAC-seq were performed to define transcriptional and epigenetic mechanisms. ResultsMNS significantly suppressed viral infection in vitro and improved survival in four lethal viral infection models, accompanied by reduced viral loads and attenuated tissue injury. MNS also diminished virus-triggered and LPS-triggered inflammatory cytokine production in macrophages and multiple mouse organs, and protected mice from LPS-induced endotoxic lethality. Multi-omics profiling showed that MNS broadly repressed LPS-induced inflammatory transcriptional programs and reversed chromatin accessibility gains across promoters and transcription start sites. Joint analysis of RNA-seq and ATAC-seq data demonstrated consistent downregulation of pivotal inflammatory pathways, such as NF-{kappa}B, Toll-like receptor, and TNF signaling. ConclusionsWith potent activity against viral replication and inflammation in cellular and animal models, MNS emerges as a promising candidate for the treatment of viral infections and hyperinflammatory conditions.

systems biology↗

bioRxiv2026

Virtual Cells Need Context, Not Just Scale

The intersection of AI and biology has entered a phase of explosive growth, driven by the ambition to build "Virtual Cells" or computational models capable of predicting cellular responses to any perturbation. Following the success of structural biology (e.g., AlphaFold) and large language models, the field has converged on training massive, high-capacity models on large-scale single-cell data. This position paper argues that scaling model capacity is insufficient to solve the Virtual Cell problem because the primary failure mode is a lack of adequate coverage over diverse biological contexts, not insufficient model expressivity. We support this claim by reviewing recent studies showing that simple baselines perform on par with sophisticated architectures within a given biological context, and current models fail to consistently generalize across contexts. We connect this finding to the causal inference literature on transportability and contrast it with domains where scaling has succeeded. We substantiate our argument through analysis of a state-of-the-art model on a 22-million-cell immunology dataset. We conclude that the community faces a causal transport problem that cannot be solved by accumulating more data from the same distributions. Instead, we argue that contextual diversity and causal representation learning deserve increased emphasis, complementing ongoing scaling of model capacity and data volume.

genomics↗