Biology subjects

Liu, L.

Publications and source records attributed to Liu, L..

At least 199 records · Page 11Linked to original sources

bioRxiv2025

LENG8 mediates RNA nuclear retention and degradation in eukaryotes

In eukaryotes, incompletely processed and misprocessed mRNAs as well as numerous noncoding RNAs are retained in the nucleus and often degraded. However, the mechanisms for this critical quality control pathway remain poorly understood. Here we identify LENG8 as a conserved RNA nuclear retention factor. We showed that LENG8 is recruited to pre-mRNAs by splicing factors, including the U1 snRNP. LENG8 binds to PCID2 and SEM1 to form the REX (Repressor of EXport) complex, which is conserved from yeast to human, and causes RNA nuclear retention by acting as a dominant negative factor for the essential mRNA export factor TREX-2. LENG8 depletion leads to the leakage of misprocessed mRNAs, including intronically polyadenylated and intron-retained mRNAs, as well as noncoding RNAs into the cytoplasm. Finally, LENG8 promotes RNA degradation by recruiting PAXT and the RNA exosome. Thus our study revealed a conserved quality control mechanism for eukaryotic gene expression that ensures only fully and correctly processed RNAs are exported from the nucleus.

molecular biology↗

bioRxiv2025

Spatial Transcriptomics Reveal Developmental Dynamics of the Human Cerebral Cortex and Striatum

The human fetal brain undergoes morphological changes that contribute to the development of regional functionalities. However, the features of structural development, the underlying molecular and cellular signatures in the fetal brain remain unclear. With spatial transcriptomics and snRNA-seq, we identified 25 forebrain regions and characterized the dynamic changes in the cortex and striatum during the late first and early second trimesters. In particular, we discovered that temporal lobe enriched NPY-expressing L2/3 EX neuron potentially interacted with L4 EX neurons during cortical expansion and arealization. Additionally, the gyrus and sulcus were developmental asynchronous, in which HOPX and SPARC genes were potentially involved. Further investigation on the striatum showed specific genes and cell types that enriched in patch and matrix compartments, and SST-positive interneurons potentially involved in the development of these structures. Together, our results give insights into the understanding of early fetal brain development.

bioinformatics↗

bioRxiv2025

RESM: Capturing sequence and structure encoding of RNAs by mapped transfer learning from ESM (evolutionary scale modeling) protein language model

RNA sequences exhibit lower evolutionary conservation than proteins due to their informationally constrained four-letter alphabet, compared to the 20-letter code of proteins. More limited information makes unsupervised learning of structural and functional evolutionary patterns more challenging from single RNA sequences. We overcame this limitation by mapping RNA sequences to pseudo-protein sequences to allow effective transfer training from a protein language model (protein Evolution-Scale Model 2, protESM-2). The resulting RNA ESM (RESM) outperforms 12 existing RNA language models in zero-shot prediction, not only in sequence classification but also in RNA secondary structure and RNA-RNA interaction prediction. Further supervised fine-tuning demonstrates RESMs generalizability and superior performance over the existing models compared across multiple downstream tasks, including mRNA ribosome loading efficiency and gene expression prediction, despite RESM being trained exclusively on noncoding RNAs. Moreover, RESM can generalize to unseen sequences beyond its 1,024-nucleotide training limit, achieving 81.3% improvement over state-of-the-art methods in supervised secondary structure prediction for RNAs up to 4,000 nucleotides, limited only by the available GPU memory, while providing >1000-fold speedup compared to MSA-based approaches. RESM provides a robust foundation for deciphering RNA sequence-structure-function relationships, with broad implications for RNA biology.

bioinformatics↗

bioRxiv2025

Antagonistic interactions between CLAVATA receptors shape maize ear development

Meristem activity is controlled by the CLAVATA (CLV) signaling pathway, which involves a suite of leucine rich receptor (LRR) receptors, receptor-like proteins and CLV- EMBRYO SURROUNDING REGION (CLE) peptide ligands. FASCIATED EAR 3 (FEA3) is a leucine rich receptor (LRR) receptor-like protein important for meristem maintenance in maize, and acts independently of canonical CLV receptors. Weak alleles of fea3 can increase yield-related traits in maize, so understanding how FEA3 controls inflorescence development can maximize its potential as a crop improvement target. To identify FEA3s interaction network, we used TurboID-based proximity labeling in maize meristems, and identified a putative co-receptor, BARELY ANY MERISTEM 1D (BAM1D). BAM1D and FEA3 proximity labeling proteomes shared over 100 proteins, including many signaling proteins, suggesting they feed into a common signaling pathway. fea3 was epistatic to bam1d in the control of IM size, supporting the idea that FEA3 and BAM1D interact physically. However, fea3 and bam1d act antagonistically, because fea3 mutants had larger inflorescence meristems (IMs), whereas bam1d mutants produced smaller IMs. Together, this study demonstrates how in vivo TurboID-based proximity labeling clarifies complex genetic interactions between CLV receptors and expands our knowledge of downstream signaling components of CLV signaling pathways, which are largely uncharacterized. Our findings support the notion that multiple, partially overlapping CLV receptor complexes coordinately control meristem maintenance.

plant biology↗

bioRxiv2025

HPInet: Interpretable prediction of Host-Pathogen protein-protein Interactions using a transformer-based neural network

Gram-negative bacteria utilize a series of secretion systems (T1SS-T10SS) to deliver secreted effector proteins (T1SE-T10SE) into host cells, leading to infections and diseases. Understanding the interactions between these effector proteins and host proteins is crucial for unraveling the pathogenic mechanisms of bacterial pathogens. Despite advancements in sequencing technologies that have significantly enhanced our knowledge of effector protein diversity and structure, the molecular mechanisms underlying their interactions with human host proteins remain unclear. Experimental approaches to validate these interactions are labor-intensive, time-consuming, and insufficient to comprehensively map the extensive effector-host protein interaction (PPI) network. Additionally, specialized computational tools for predicting these interactions remain scarce. To address this gap, we developed HPInet, a transformer-based deep learning model for predicting interactions between bacterial effector proteins and human host proteins. HPInet introduces convolutional layers and global response normalization (GRN) into the feed-forward network (FFN) of the transformer architecture, enhancing the extraction of local sequence features. Compared to existing state-of-the-art methods, HPInet significantly improves prediction performance, increasing accuracy from 0.502 to 0.891 and boosting sensitivity by 35.3%. Furthermore, by leveraging the models attention mechanism, HPInet identifies critical residues at interaction sites, demonstrating its capability to capture local structural features of PPI sites solely from sequence information. To facilitate its application in research, HPInet has been implemented as a freely accessible web server available at https://bis.zju.edu.cn/hpinet. This platform provides a powerful and interpretable tool for studying effector-host protein interactions, offering valuable insights into bacterial pathogenesis and potential therapeutic targets.

bioinformatics↗

bioRxiv2025

Profiling and Functional Analysis of Urinary Exosomal MicroRNAs in Pregnant Women with Systemic Lupus Erythematosus

BackgroundPregnancy in Systemic Lupus Erythematosus (pSLE) is high-risk, necessitating non-invasive biomarkers for monitoring and predicting complications. Urinary exosomes, containing miRNAs, offer a promising source reflecting systemic and renal states, yet their profile in late gestation pSLE is less studied. ObjectiveThis study aimed to investigate the profile of urinary exosomal miRNAs in pregnant women with SLE during late gestation compared to healthy pregnant controls and to explore their potential biological roles and pathways. MethodsUrinary exosomes were isolated from 6 pSLE patients and 5 controls. Exosomes were characterized, and miRNAs were sequenced. Bioinformatics analyses, including target gene prediction and functional enrichment (GO, KEGG), were performed. ResultsExosomes were successfully isolated. Sequencing identified 29 significantly downregulated miRNAs in pSLE exosomes. Enrichment analysis of these miRNAs and their target genes indicated involvement in metabolic and immune pathways, virus infection, and cellular senescence. Target genes also enriched in protein stability and transport, and high-level analysis showed broader roles in metabolic, immune, and cellular maintenance/stress processes. Targets of top differentially expressed miRNAs linked to mRNA regulation, AMPK, and senescence pathways. ConclusionOur findings demonstrate that urinary exosomal miRNAs are significantly altered in pregnant women with SLE during late gestation. The functional enrichment analysis suggests their target genes are involved in critical biological processes relevant to pSLE pathophysiology and pregnancy complications, including metabolism, immunity, viral response, senescence, and cellular maintenance. This highlights the potential of urinary exosomal miRNAs as non-invasive biomarkers for monitoring and predicting risks in this high-risk population.

immunology↗

bioRxiv2025

Barley BODYGUARD controls cuticular specialisations regulated by SHINE transcription factors

The outer epidermis of land plants secretes a cuticular layer, a hydrophobic diffusion barrier which minimises water loss into the atmosphere and protects from pests, ultraviolet light and organ fusion. Cuticles typically comprise a polyester cutin matrix embedded and overlaid with cuticular waxes, but their exact chemical make-up, structure and functions can vary widely depending on the tissue and species. Barley shows two such cuticular specialisations: (1) deposition of a thick {beta}-diketone-rich wax bloom on multiple organs at reproductive stage, common in other Poeceae species and linked to yield; and, (2) secretion of a sticky layer on the grain fruit (caryopsis) pericarp cuticle which adheres to inner floral hulls, leading to barleys distinctive covered grain used in animal feed and malting. Two SHINE/WAX-INDUCER transcription factors in barley, HvWIN1 and NUD, promote the wax bloom and hull to caryopsis adhesion, respectively, yet little is understood about other genes involved. Leveraging near-isogenic lines of wax-deficient mutants, we identify the barley BODYGUARD1 (HvBDG1) gene encoding an /{beta}-hydrolase essential for leaf cuticular integrity and wax bloom deposition. Modelling of functional and defective alleles suggests that HvBDG1 N-terminal region control of protein flexibility is important for HvBDG1 function. In addition to their role in controlling barley epicuticular wax deposition, we show that both HvBDG1 and HvWIN1 are essential for strong hull to caryopsis adhesion. Along with NUD, these gene products differentially contribute to ultrastructural changes on the pericarp associated with a cuticular building programme driven by NUD and HvWIN1 regulation of cuticle metabolism and transport and cell wall-related genes, and correlate with shifts in pericarp surface chemistry. We also show that the previously asserted grain-specific role of NUD should be revised, as our findings reveal that it is essential for maintaining leaf cuticle integrity. Our analyses in barley suggest that NUD and HvWIN1 control cuticular specialisations and cuticle integrity in part via promotion of HvBDG1 expression, while HvWIN1 and NUD likely act independently from each other. Lastly, mining tetraploid wheat mutant populations followed by crossing to combine mutated homoeologues demonstrated that BDG1 and WIN1 orthologues also control wax bloom in wheat. Taken together, our work greatly expands the genetic networks and molecular activities important for cuticle development in cereals and the underlying mechanisms for both shared and species-specific cuticular specialisations.

plant biology↗

bioRxiv2025

From Black Box to Biological Insight: AttentioFuse Unlocks Multi-Omics Dynamics in Lung Cancer

Lung adenocarcinoma (LUAD) and squamous cell carcinoma (LUSC), the major subtypes of non-small cell lung cancer (NSCLC), exhibit distinct molecular landscapes that demand precision in prognosis and therapy. While deep learning models achieve high predictive accuracy, their "black-box" nature limits clinical translation. To address this, we propose AttentioFuse, an interpretable deep learning framework employing a Reactome-guided mid-fusion strategy for multi-omics integration. AttentioFuse innovates through three pillars: (1) dual-phase learning to preserve omics-specific patterns via independent sub-networks, (2) hierarchical attention mechanisms (cross-omics, feature-level, and fusion-layer) to dynamically quantify layer contributions, and (3) integrated explainability combining DeepSHAP and global attention weights for gene-to-pathway interpretation. Evaluated on TCGA LUAD/LUSC cohorts, AttentioFuse matches state-of-the-art performance in TNM staging, while uncovering actionable biological insights. The framework validates pan-NSCLC mechanisms like AKT/mTOR metabolic control and histology-divergent Notch signaling roles, while revealing novel pathways--developmental reactivation (T-stage), microbiota-driven metastasis (M-stage), and ECM remodeling--providing testable hypotheses for progression and personalized therapy. Crucially, AttentioFuse bridges computational predictions to clinical practice by proposing molecularly-guided combination therapies. This paradigm shifts toward interpretable-aware AI advances oncology by transforming black-box predictions into biologically grounded decision-support tools.

bioinformatics↗

bioRxiv2025

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↗

bioRxiv2025

Occurrence and temporal dynamics of denitrifying protist endosymbionts in the wastewater microbiome

Effective wastewater treatment is of critical importance for preserving public health and protecting natural environments. Key processes in wastewater treatment, such as denitrification, are performed by a diverse community of prokaryotic and eukaryotic microbes. However, the diversity of the microbiome and the potential role of the different microbial taxa in some wastewater treatment plant setups is not fully understood. We aimed to investigate the presence and diversity of denitrifying bacteria of the candidate family Azoamicaceae that form obligate symbioses with protists in wastewater treatment plants. Our analyses showed that denitrifying endosymbionts belonging to the Ca. Azoamicus genus are present in 20-50% of wastewater treatment plants worldwide. Time-resolved amplicon data from four Danish wastewater treatment plants showed high temporal fluctuations in the abundance and composition of the denitrifying endosymbiont community. Fifteen high-quality metagenome-assembled genomes of denitrifying endosymbionts, four of which were circular, were recovered. Genome annotation showed that a newly described, globally widespread species, Ca. Azoamicus parvus, lacked a nitrous oxide reductase, suggesting that its denitrification pathway is incomplete. This observation further expands the diversity of metabolic potentials found in denitrifying endosymbionts and indicates that the contribution of microbial eukaryote holobionts to the wastewater ecosystem dynamics of nitrogen removal and greenhouse gas production may have been underestimated and needs further study.

microbiology↗

bioRxiv2025

TIGAR DEFICIENCY ENHANCES CARDIAC RESILIENCE THROUGH EPIGENETIC PROGRAMMING OF PARKIN EXPRESSION

BACKGROUNDWhile mitochondrial dysfunction clearly drives cardiac deterioration in major heart diseases, the mechanisms controlling mitochondrial quality remain incompletely understood. This study investigated whether TIGAR (TP53-induced glycolysis and apoptosis regulator) deficiency influences cardiac protection through mitochondrial quality control pathways. METHODSWe generated both whole-body and cardiomyocyte-specific TIGAR knockout mice that were assessed for cardiac function following myocardial infarction (induced by left anterior descending coronary artery ligation) and diet-induced cardiomyopathy (using a 6-month high-fat diet protocol). Mitochondrial quality control was evaluated through mitophagy assays, subcellular fractionation, and molecular analyses. Epigenetic regulation was assessed using whole-genome bisulfite sequencing, chromatin immunoprecipitation, and CRISPR-mediated gene editing in multiple cell lines. RESULTSBoth whole-body (TKO) and cardiomyocyte-specific (hTKO) TIGAR knockout mice demonstrated cardioprotection following myocardial infarction. These animals maintained significantly better ejection fraction (43.35{+/-}17.76% vs 26.36{+/-}9.83% in wild-type controls, P<0.05) and displayed complete resistance to diet-induced cardiac hypertrophy, despite comparable weight gain. TIGAR deficiency led to dramatic increases in Parkin expression across multiple tissues, 6-fold increases in heart and muscle, and 5-fold increases in brain, which enhanced mitophagic responses during metabolic stress conditions including fasting and high-fat diet feeding. Generation of Parkin/TIGAR double knockout mice eliminated this protection, confirming Parkins essential role. Notably, adult manipulation of TIGAR through viral overexpression or knockdown failed to alter Parkin levels, suggesting developmental programming. Whole-genome bisulfite sequencing revealed reduced DNA methylation in a specific 3.2 kb region within Parkin gene intron 10, and CRISPR deletion of this regulatory region increased Parkin expression 10-fold in C2C12 myoblasts and 6-fold in 3T3-L1 fibroblasts. CONCLUSIONSThese findings reveal a novel TIGAR-Parkin regulatory axis operating through epigenetic mechanisms during cardiac development to establish lifelong cardioprotection via enhanced mitochondrial quality control. This discovery points toward new therapeutic approaches targeting developmental metabolic programming for heart disease prevention and identifies specific epigenetic targets for cardiovascular therapy. CLINICAL PERSPECTIVEO_ST_ABSWhat Is New?C_ST_ABSO_LITIGAR deficiency establishes lifelong cardiac protection through developmental epigenetic programming of Parkin expression. C_LIO_LIA novel 3.2 kb differentially methylated region in Parkin intron 10 regulates mitochondrial quality control in the heart. C_LIO_LIEarly metabolic programming during cardiac development can establish permanent cardioprotective phenotypes. C_LIO_LIThe TIGAR-Parkin axis provides protection against both acute ischemic injury and chronic metabolic cardiomyopathy. C_LI What Are the Clinical Implications?O_LITargeting the TIGAR-Parkin pathway could provide novel therapeutic approaches for preventing both ischemic heart disease and diabetic cardiomyopathy. C_LIO_LIEarly developmental interventions targeting cardiac metabolism might establish lifelong cardiovascular protection. C_LIO_LIEpigenetic modifications of mitochondrial quality control genes represent potential therapeutic targets. C_LIO_LIThe findings suggest optimal timing for cardiovascular preventive interventions may be during critical developmental windows. C_LI

molecular biology↗

bioRxiv2025

Reproducible detection of antigen-specific T cells and Tregs via standardized and automated activation-induced marker assay workflows

Activation-induced marker (AIM) assays are a promising tool to track antigen-specific T cells, but methodological heterogeneity between research groups hinders their clinical utility. To evaluate AIM assay reproducibility, we conducted a multi-site study of SARS-CoV-2 and cytomegalovirus AIMs. We found inherent variability in AIM assays and optimized approaches to enhance reproducibility, including a standardized workflow to minimize technical variability and a generalizable Box-Cox transformation-based statistical method to optimize calculation of AIM stimulation responses. We further standardized AIM data analysis through development of automated flow cytometric gating software, which had superior reproducibility compared to manual analysis. We also characterized antigen-specific Tregs, finding that gating on a combination of CD134, CD137, FOXP3 and HELIOS optimally detects antigen-specific cells. The combined methodology results in a high degree of reproducibility within and between research groups and provides a comprehensive foundation from which standardized AIM assays can be implemented across diverse scientific and clinical settings. MOTIVATIONReliable detection of antigen-specific T cells is critical to understand immune responses to infection and vaccination, and has translational potential to monitor T cell responses across diverse clinical settings. Activation-induced marker (AIM) assays offer a variety of advantages over methods such as ELISPOT and tetramers, but are limited by methodological heterogeneity between research groups and a lack of standardized protocols. As such, the degree to which AIM assay results are reproducible is unknown. Key variables such as cell source, media, stimulation time, marker selection for CD4+ T cells, CD8+ T cells and regulatory T cells; as well as data analysis parameters such as flow cytometric gating strategies and mathematical correction for background AIM+ frequencies in unstimulated control samples, have not been rigorously studied. To address this, we comprehensively characterized variability in AIM assays, including within and between operators and across multiple research centres, and sought to optimize a standard AIM workflow to enhance reproducibility at both the experimental and analytical levels.

immunology↗

bioRxiv2025

Pluripotent stem cell-derived siTNK cells attack tumors via a synthetic CD8-CD28 TCR complex

Tumor-associated antigen-specific T cell receptor (TCR)-engineered T cells offer a promising strategy for cancer therapy. Natural killer (NK) cells exhibit broad anti-tumor activity with low side effects but lack the capacity to recognize intracellular antigens. Here, we found that the human pluripotent stem cell (hPSC)-derived iNK cells, unlike tissue-isolated NK cells, expressed all four CD3 subunits at the transcriptome level. We introduced a synthetic gene-expressing complex (SCOTR), encoding a tumor antigen- specific TCR, CD8 coreceptor, and CD28 costimulatory molecule, into hPSCs to generate SCOTR-hPSCs. The SCOTR-hPSCs gave rise to abundant synthetic TCR complex-expressing iNK (siTNK) cells via an organoid induction method. These siTNK cells showed HLA-dependent, antigen-specific cytotoxicity against tumor cells and significantly suppressed tumor growth in tumor xenograft animal models, while also preserving universal non-specific tumor-killing activity. Collectively, siTNK cells, as hPSC-derived hybrid cells with dual features of adaptive T and inherent NK cells, offer an artificial cell source for human immunotherapies.

immunology↗

bioRxiv2025

Neural Timescale of Adolescents Major Depressive Disorder

Adolescent major depressive disorder (MDD) is characterized by heterogeneous symptomatology and complex neurodevelopmental underpinnings. Here, we investigated whether cortical intrinsic neural timescales (INT)--a measure of temporal stability in neural activity--are altered in adolescents with MDD and whether these alterations relate to clinical symptoms, suicidality, early-life adversity, and underlying neurobiological mechanisms. Using resting-state fMRI in adolescents with MDD and healthy controls (HCs), we found widespread reductions in INT in frontal, parietal, and sensorimotor regions, with a notable prolongation in the left temporoparietal junction. Disrupted timescales significantly impaired network modularity and clustering, and SVR-based machine learning revealed that altered INT patterns predicted individual depression and anxiety severity. INT abnormalities were further associated with suicidal ideation and childhood trauma, particularly emotional and physical neglect. Biophysical modeling linked INT variations to local recurrent excitation and external input strength, differing between HCs and MDD. Spatial correlations with PET-derived neurotransmitter receptor maps demonstrated that INT alterations colocalize with serotonergic, dopaminergic, and cholinergic systems. Transcriptomic enrichment analysis revealed associations with genes involved in mitochondrial function, synaptic signaling, and metabolic regulation. Together, these findings identify neural timescale disruption as a core pathophysiological feature of adolescent MDD, bridging macroscale dynamics with microcircuit and molecular architecture. INT may serve as a promising biomarker and mechanistic target for precision psychiatry in youth depression.

neuroscience↗

bioRxiv2025

Multifaceted mRNA analysis using programmed RNA cleavage byMucilaginibacter paludis Argonaute

Argonaute (Ago) endonucleases are ubiquitous across all domains of life and, like Cas nucleases, can be programmed by guide oligonucleotides to target and cleave specific nucleic acid sequences. However, unlike Cas enzymes, Agos are not restricted by sequence requirements such as protospacer adjacent motifs (PAMs) enhancing their utility as molecular tools. This study demonstrates diverse applications of the DNA-guided RNA-endonuclease Mucilaginibacter paludis Argonaute (Mpa Ago) for in vitro mRNA processing, e.g., 3 end polishing, and for mRNA analysis in combination with liquid chromatography tandem mass spectrometry (LC-MS/MS). Applications of the latter include the comprehensive assessment of 5 capping efficiency, 3 poly(A) tail length and composition, one-pot multiplexed cleavage for RNA sequencing, modification detection, and fingerprinting.

molecular biology↗

bioRxiv2025

Specificity of Aberrant Exons in a Saturated Background of Differentially Expressed Exons

Determining the maximal specificity of aberrant exons from multifactorial disease tissues in a whole body background could provide insights into the exon origin as well as potential targets of diagnosis or therapy, but it remains a challenging task. For this purpose, we obtained a saturated list of differentially expressed exons (DEXs) from our independent reference human exome extracted from 56 normal tissues by DEXSeq. We found that the DEXs comprised the majority of the reference exome and that 99.4% of cancer-specific exons relative to paired normal tissues fell within the DEX list, consistent with the ectopic expression of the majority of aberrant exons. We then screened over seven thousand pathogenic single nucleotide variants (SNVs) in the TCGA and COSMIC databases by SpliceAI. The analysis identified over three hundreds of highly confident, mostly somatic SNV-specific splicing events and/or novel exonic fragments in five types of adenocarcinomas. Interestingly, these events are all associated with cis-acting mutations in tumor suppressor genes, particularly in TP53 with an antigenic novel peptide. This revelation of the DEX exome dominance and non-specificity of nearly all aberrant exons not only reshapes our understanding of the normal human exome by highlighting its mainly variable over constitutive exons, but also illuminates the path through cis-acting somatic and pathogenic SNVs to identify genuine cancer-specific exonic fragments that are absent in any normal tissues, beyond neo-exon junctions. This path holds promise for identifying novel peptide fragments for antigens in holistic cancer treatments including vaccination and immunotherapies.

cancer biology↗

bioRxiv2025

A Novel 'Three-in-one' Mucosal Vaccine Elicits Broad Protection against Three Distinct Clusters of ACE2-using Sarbecoviruseses

With the persistent risk of coronavirus epidemics, the development of universal vaccines is urgently needed and challenging to achieve. In this study, we aimed to design a multivalent immunogen to provide broad protection against diverse ACE2-using sarbecoviruses, which pose a significant threat to global health. Our analysis revealed that the receptor-binding domains (RBDs) of ACE2-using sarbecoviruses segregate into three antigenically distinct clusters, including one cluster that encompasses viruses related to SARS-CoV-2. Based on these findings, we engineered a three-in-one immunogen, designated as 3Rs-NC, which incorporates representative RBDs from all three clusters. 3Rs-NC preserved the natural epitope configuration of each monomeric RBD component, and efficiently elicited high levels of neutralizing antibodies against representative viruses and closely related sarbecoviruses. When administered intranasally with flagellin-based mucosal adjuvant KFD, 3Rs-NC induced robust and durable RBD-specific serum IgG and mucosal IgA responses in mice. Furthermore, KFD-adjuvanted 3Rs-NC conferred sustained protection in both the upper and lower respiratory tracts against SARS-CoV-2 Omicron BA.1 and SARS-like coronavirus WIV1. Additionally, 3Rs-NC immunization protected mice from lethal challenge of SARS-like coronavirus rRsSHC014S, with more efficient protection observed in female mice than male mice. This needle-free three-in-one vaccine represents a promising candidate for a universal mucosal vaccine against ACE2-using sarbecoviruses and could serve as a foundational component of three-in-one vaccine series to form a comprehensive coronavirus vaccine package. HighlightO_LInovel three-in-one immunogen 3Rs-NC induced a high level of neutralizing antibodies against three distinct ACE2-using Sabecovirus clusters. C_LIO_LIadministration of 3Rs-NC plus KFD adjuvant (3Rs-NC+KFDi.n) generated potent and long-lasting RBD-specific serum IgG and mucosal IgA. C_LIO_LI3Rs-NC+KFDi.n provided long-term protection in both upper- and lower-respiratory tracts in mice. C_LIO_LI3Rs-NC+KFDi.n could serve as a foundational component for next-generation coronavirus vaccine strategies. C_LI

immunology↗

bioRxiv2025

Homodimerized Arpins: Binding to Arp2/3 Complexes with Positive Synergy to Inhibit Lamellipodia-Dependent Tumor Metastasis

The Arp2/3 complex is a central regulator of actin polymerization dynamics and cancer cell motility, with its dysregulation implicated in metastasis and therapeutic resistance. Despite its therapeutic potential, targeting Arp2/3 remains challenging due to the lack of precise molecular insights into endogenous inhibitors. Arpin, a lamellipodia-localized Arp2/3 inhibitor, has emerged as a critical modulator of cancer migration; however, the structural and mechanistic basis of its inhibitory function remains unresolved. Here, we report the 1.65-[A] crystal structure of Arpins N-terminal globular domain, revealing a unique structural fold distinct from all known Arp2/3-binding factors. Structural and biophysical analyses demonstrate that Arpin forms homodimers via a conserved interface, which is essential for cooperative inhibition of Arp2/3-dependent actin polymerization. Functional studies in cancer models reveal that Arpin homodimerization potently suppresses lamellipodia-driven migration and invasion, effects further enhanced by engineered dimeric constructs or artificially designed dual-tailed peptides. These findings elucidate a structural basis for Arpin-mediated suppression of cancer cell motility and identify homodimeric cooperativity as a druggable mechanism for targeting metastatic progression. Our work provides a molecular framework for designing Arpin-inspired inhibitors to counteract therapeutic resistance and metastasis in cancers reliant on Arp2/3-driven actin dynamics.

cancer biology↗