Biology subjects

Dong, C.

Publications and source records attributed to Dong, C..

At least 19 recordsLinked to original sources

bioRxiv2026

PAXIP1-PAGR1 directs cohesin recruitment during break-induced telomere repair

Cohesin is a conserved multiprotein complex (SMC1, SMC3, RAD21, and either STAG1 or STAG2) that organizes three-dimensional genome architecture and regulates chromosome segregation, gene expression, and DNA damage repair (1-4). Following double-strand breaks (DSBs), cohesin is recruited to sites of DNA damage - a process considered essential for efficient homologous recombination (5-15). Yet how DSB signaling elicits cohesin recruitment and subsequent cohesion establishment remains poorly understood. Here we show that telomere replication stress activates de novo STAG2-cohesin loading, thereby promoting break-induced telomeric DNA repair. We demonstrate that this DNA break-elicited cohesin recruitment is strictly controlled by the BRCT domain-containing DNA damage recognition factor PAXIP1 and its functional partner PAGR1. Cryo-electron microscopy structure reveals that PAGR1, together with PAXIP1, physically binds to a composite interface formed by the STAG2-RAD21 cohesin subcomplex. Complementary mutational and biochemical analyses define the molecular basis of this interaction and establish its essential role in break-induced cohesion establishment. Furthermore, we show that PAXIP1-PAGR1-enacted STAG2-cohesin recruitment complements with the PML body-associated pathway in orchestrating break-induced alternative lengthening of telomeres (ALT). Concurrent depletion of PML together with PAXIP1, PAGR1 or STAG2 disrupts ALT-mediated telomere maintenance, leading to end-to-end chromosomal fusion and mitotic cell death. Collectively, these findings uncover a distinctive molecular mechanism through which DSB signaling directs de novo cohesion establishment, and highlight its critical importance in break-induced telomere repair.

molecular biology↗

bioRxiv2026

Parallel Arg/N-degron recognition systems regulate coenzyme A biosynthesis

Coenzyme A (CoA) is an essential metabolic cofactor whose biosynthesis is controlled by pantothenate kinases (PANKs), the rate-limiting enzymes in CoA synthesis. Although CoA production is extensively regulated, whether PANK abundance is controlled by selective protein degradation remains unknown. Here, we identify PANK1{beta} and PANK3 as substrates of the Arg/N-degron pathway. Two mechanistically distinct E3 ligase systems, UBR4-KCMF1 and MKLN1-CTLH, independently converge on a common N-terminal MK Arg/N-degron to promote PANK degradation and restrict CoA biosynthesis. UBR4-KCMF1 recognizes the MK Arg/N-degron through KCMF1 ZZ domain, whereas CTLH complex employs the B30.2-domain proteins RanBP9 and RanBP10 as previously unrecognized Arg/N-degron recognins. Structural, biochemical, and cellular analyses demonstrate that RanBP9 and RanBP10 recognize both Met-X and canonical Arg/N-degrons through their B30.2 domains, using a mechanism distinct from canonical UBR proteins. Together, these findings establish a new branch of the mammalian Arg/N-degron pathway and reveal ubiquitin-dependent control of PANK abundance in CoA homeostasis.

molecular biology↗

bioRxiv2026

A conserved transcriptional axis links cortical organization, developmental timing and autism-associated perturbations

Much of our mechanistic understanding of cortical development and neurodevelopmental disorders comes from studies in mice, yet translating these insights to humans rests on a fundamental assumption: that the cortex is organized according to conserved principles across species. Here, by independently decomposing human and mouse cortical transcriptomes, we test this assumption and identify a shared organizational axis extending from limbic anterior ventral (AV) to primary sensory posterior dorsal (PD) cortex. This axis aligns with conserved variation in cell-type composition, thalamocortical connectivity, myelination and excitation-inhibition balance. Its spatial topology emerges by mid-gestation and is progressively refined while remaining stable in orientation across subsequent development. What varies systematically along the axis is developmental timing: AV-enriched genes preferentially retained earlier cortical-construction features and progressively decline after birth, whereas PD-enriched genes preferentially reflected later maturation processes and progressively increased, with developmental rates graded along the axis. Across genetically distinct autism mouse models, developmental dysregulation converged on this axis, following a shared pattern that generally intensified toward the PD pole. The same axis also organized genotype-specific patterns of cortical volume alteration, while human autism risk genes showed corresponding enrichment along this transcriptional coordinate. Overall, we identify a conserved transcriptional axis that links cortical architecture to developmental timing and organizes the heterogeneous cortical effects of autism-associated mutations.

neuroscience↗

bioRxiv2026

Hearing Lips and Seeing Voices After Fifty Years: A Large-Scale McGurk Illusion Dataset for Audiovisual Speech Research

Efficient face-to-face communication relies on the integration of auditory speech and visual articulatory signals. Over the past five decades, the McGurk illusion has been widely used as an index of audiovisual speech integration. However, substantial variabilities in susceptibility to the illusion across participants and speakers limit its reliability as a stable measure of audiovisual integration ability. Here, we introduce the McGurk illusion dataset (MID), which, to our knowledge, is the largest publicly available McGurk stimulus dataset to date. The MID comprises auditory (N = 400), visual (N = 400), and audiovisual (N = 640) speech stimuli generated from 80 Mandarin speakers and validated through behavioral judgments across 360,900 trials. Using this dataset, we characterized the acoustic and facial articulatory properties of McGurk stimuli, replicated substantial inter-participant and inter-speaker variabilities in illusion susceptibility, and revealed the associations between variations in McGurk illusion rate and the variations in unisensory perception, audiovisual correspondences, and speakers characteristics. Furthermore, the stimulus set enabled systematic comparisons of the reliability of different McGurk illusion-based indices of audiovisual speech integration. Overall, the MID not only provides a standardized resource for investigating audiovisual speech integration and its alterations across populations, but also supports research on speaker normalization, lip-reading, and speech perception.

neuroscience↗

bioRxiv2026

Structure-Property-Performance Engineering of Hydrogel Depots for Long-Acting Peptide Delivery

Controlled release systems for subcutaneous peptide delivery often exhibit a pronounced initial burst release followed by inadequate maintenance of therapeutic exposure, limiting depot lifetime and increasing pharmacokinetic variability. Here, we engineer a dynamic, injectable hydrogel depot technology for months-long delivery of lipidated peptides. Using semaglutide as a model, we establish a modular formulation framework integrating: (i) formulation-driven tuning of depot mechanics to control release kinetics, (ii) cargo complexation strategies leveraging hydrophobic and multivalent ion-mediated interactions, and (iii) oxidative stabilization through sacrificial antioxidant excipients. We evaluated depot performance by rheology, in vitro cargo release, and in vivo pharmacokinetic and pharmacodynamic studies in rodents. Optimized formulations sustained semaglutide exposure for over six weeks from a single administration with two-fold reduction in peak-to-trough exposure and comparable total bioavailability relative to daily dosing, resulting in improved glucose control, weight regulation, and preservation of pancreatic islet content. These results suggest potential for quarterly dosing in humans. Together, this work establishes integrated and generalizable structure-property-performance relationships that account for cargo-matrix and cargo-excipient interactions across burst, diffusion, and erosion regimes to inform a practical formulation framework for engineering long-acting depots for sustained peptide delivery.

bioengineering↗

bioRxiv2026

Hierarchical Interplay between H3K27ac and H3K4me3 in Transcriptional Regulation

H3K27ac and H3K4me3 are enriched at transcriptional start sites and have been implicated in transcription. However, how these marks concertedly regulate transcription is not fully understood. Here, we developed a dual chemically inducible CRISPR/dCas9-based epigenome editing system that enables independent, temporal and transcription stage-specific modulation of H3K27ac and H3K4me3 at a specific gene locus. Stage-specific removal of H3K4me3 impaired RNA polymerase II recruitment, increased promoter-proximal pausing, reduced productive elongation, and accelerates mRNA decay via increased m6A deposition. Losing both H3K27ac and H3K4me3 rapidly abolished transcriptional activity, while preserving H3K4me3 without H3K27ac can partially sustain transcription. These findings revealed a functional hierarchy and interdependence between H3K27ac and H3K4me3 in different transcription stages and the established versatile tool will contribute to the functional dissection of the temporal dynamics of chromatin modifications in gene regulation.

genomics↗

bioRxiv2026

Cellular Mechanisms of Transcranial Magnetic Stimulation in Climbing Fibers and Purkinje Neurons in the Cerebellum

Although transcranial magnetic stimulation (TMS) is widely used for brain stimulation, fundamental issues about its underlying mechanisms remain unresolved. We investigated some of these issues experimentally using an intact isolated turtle cerebellum in vitro, employing a novel chamber designed to deliver precisely calibrated induced electric fields along cortical depth. Our results show that single-pulse TMS can directly activate Purkinje cells and climbing fibers, and synaptically activate Purkinje cells via climbing fibers - all within the first 1.2 ms. Specifically, current source density analysis showed that TMS directly (non-synaptically) activated (1) climbing fibers near the bend with intracellular current directed toward the axonal terminals and (2) Purkinje cells directly near the axon initial segment with intracellular current directed toward the distal dendrites. The thresholds for direct activation of climbing fibers and Purkinje cells were found to be very similar, 25 {+/-} 1 V/m. The climbing fibers synaptically activated Purkinje cells, as expected, with intracellular current originating in the proximal dendritic trunk and directed toward the distal dendrites. At higher electric fields (> 58 {+/-} 17 V/m), TMS synaptically activated dendritic currents in Purkinje cells. These results provide new insight into how TMS may activate afferent fibers and cell bodies of cortical neurons.

biophysics↗

bioRxiv2026

A cinnamyl alcohol dehydrogenase scaffold organizes monoterpenoid indole alkaloid biosynthesis

Biosynthesis of ~3,000 monoterpenoid indole alkaloids (MIAs), including the anticancer drug vinblastine, involves the highly unstable intermediate strictosidine aglycone. Its formation by strictosidine {beta}-glucosidase (SGD) and subsequent conversion by geissoschizine synthase (GS) occur in spatially separated compartments, representing a major biosynthesis bottleneck. Here we discover VinBLAST, a cinnamyl alcohol dehydrogenase-like protein repurposed as a scaffold for efficient processing of this labile intermediate. VinBLAST physically mediates SGD and GS interaction in the nucleus and allosterically enhances GS catalytic efficiency. VinBLAST homologues from diverse plant families enhance biosynthesis of several representative MIAs, with the production of catharanthine increased to ~160 mg L-1 in yeast, nearly 1,000-fold higher than previous studies. Our discovery provides a missing link in organizing MIA biosynthesis and enables scalable bioproduction of geissoschizine-derived therapeutics.

synthetic biology↗

bioRxiv2026

Exploring Chromosomal Position Effects for Predictable Tuning of Metabolic Pathways in Yeast

Precise control of gene expression is essential for optimizing metabolic pathways, yet current tuning strategies based on promoter strength or gene copy number remain largely empirical. Chromosomal position represents an additional regulatory axis, as identical gene expression cassettes can exhibit markedly different expression levels depending on their integration sites. Here, we systematically quantified the expression output of 98 intergenic regions (IGRs) in Saccharomyces cerevisiae using a fluorescent reporter and developed a predictive framework, Yeast IGR Prophet (YeIP), that infers expression potential directly from genomic context. By integrating multi-scale genomic features including transcriptional neighborhood, chromatin state, and chromosome topology, YeIP accurately predicted expression ranks and enabled the construction of a genome-wide atlas of expression hotspot and coldspot. Using this atlas, we rationally optimized a three-gene lycopene pathway solely through genomic integration site selection, achieving optimal transcriptional stoichiometry without modifying promoters or gene copy numbers. These results transform chromosomal integration sites from static genomic coordinates into programmable regulatory elements, establishing a predictive, data-driven framework for rational and scalable design of metabolic pathways in yeast.

synthetic biology↗

bioRxiv2026

eSIG-Net: Accurate prediction of single-mutation induced perturbations on protein interactions using a language model

Most proteins exert their functions in complex with other interactors. Single mutations can exhibit a profound impact on perturbing protein interactions, leading to human disease. However, predicting the effect of single mutations on protein interactions remains a major computational challenge. Deep learning, particularly protein language models or transformers, has become an effective tool in bioinformatics for protein structure prediction. However, the functional divergence of mutations makes it difficult to predict their interaction perturbation profiles. To address this fundamental challenge, we present eSIG-Net (edgetic mutation Sequence-based Interaction Grammar Network), a novel sequence-based "Interaction Language Model" for predicting protein interaction alterations caused by single mutations. eSIG-Net combines various protein sequence embeddings, introduces a mutation-encoding module with syntax and evolutionary insights, and employs contrastive learning to evaluate mutation-induced interaction changes. eSIG-Net significantly outperforms current state-of-the-art sequence-based and structure-based prediction methods at predicting mutational impact on protein interactions. We highlight examples where eSIG-Net nominates causal variants with high confidence and elucidates their functional role under relevant biological contexts. Together, eSIG-Net is a first-in-kind "interaction language model" that can accurately predict interaction-specific rewiring by single mutations with only sequence information, and exhibits generalizability across biological contexts.

bioinformatics↗

bioRxiv2026

Decoding Immunomodulatory Hydrogels for Arthritis: Comparative Insights from Predictive Machine Learning and Large Language Models

Hydrogels are increasingly recognized as promising therapeutics for arthritic joints, extending their traditional role as mechanical lubricants to modulators of joint immunity. However, the rational design of these materials remains challenging, with progress largely driven by empirical experimentation. To address this, we curated a comprehensive database of 220 hydrogel formulations from 317 published studies and applied an interpretable machine learning (ML) framework to uncover the relationships between hydrogel design parameters and the arthritis severity score. Using a Random Forest algorithm, our model achieved an external validation accuracy of 0.67 in predicting effective hydrogel therapies for arthritis. Analysis revealed a clear hierarchy of design principles: the choice of functional agent, base polymer, and elastic modulus were the most influential predictors of therapeutic efficacy, with composite agents, protein-based polymers, and softer hydrogels most strongly associated with positive therapeutic outcomes. Mechanistic investigations further demonstrated that successful hydrogels promote an anti-inflammatory M2 macrophage phenotype. Benchmarking against classical statistical methods and a large language model framework showed that our ML approach provided more robust, nuanced insights into complex feature interactions. This data-driven framework offers a generalizable blueprint for the rational design of next-generation immunomodulatory hydrogels, paving the way for more effective arthritis therapies.

bioengineering↗

bioRxiv2026

Construction of a GnRH mRNA Immunocastration Vaccine and Evaluation of Its Immunogenicity and Safety in Mice and Cats

Immunocastration has emerged as an alternative to surgical and chemical castration for managing reproductive function in animals, yet the development of safe and effective vaccines remains challenging. This study aimed to develop a gonadotropin-releasing hormone (GnRH)-based messenger RNA (mRNA) vaccine and systematically evaluate its immunogenicity, reproductive suppression efficacy, long-term durability, and biosafety in mice and cats. GnRH epitopes were fused to three carrier proteins, Fc, Foldon, and lumazine synthase nanoparticles (pLS) via a flexible linker. After identifying pLS as the optimal scaffold, three mRNA vaccine candidates (GnRH-3, GnRH-4, and GnRH-5) were generated with one, five, or ten tandem GnRH repeats, encapsulated in lipid nanoparticles (LNPs), and assessed in rodent and feline models. Immunogenicity was determined by enzyme-linked immunosorbent assay, gonadal histopathology, hormone measurements, transcriptomic analysis, and mating trials. Among the fusion partners, the pLS-based vaccine (GnRH-3) induced the strongest antibody responses and most pronounced reproductive suppression. Further optimization showed that GnRH-4, containing five tandem GnRH repeats, elicited the highest antibody titers, induced severe gonadal atrophy, and reduced litter size by 93.8% in mice. Transcriptomic analysis revealed that differentially expressed genes in males were enriched in spermatogenesis and motility pathways, whereas those in females were associated with RNA splicing and immune responses. In cats, the optimal regimen was a twoLdose schedule with 50Lg per dose and a 21Lday interval, which induced robust antibody responses lasting at least 12 Lmonths and sustained reproductive suppression. HighLdose (500Lg) administration showed no clinical toxicity or histopathological abnormalities, confirming favorable biosafety. This study successfully developed a pLSLbased GnRH mRNA vaccine (GnRH-4) with five tandem GnRH epitopes that demonstrates strong immunogenicity, longLlasting contraceptive effects, and excellent safety in both rodent and feline models, supporting its potential for clinical application in immunocastration.

immunology↗

bioRxiv2026

Domain Specific Functional Plasticity of Visual Processing Constrained by General Cognitive Ability in Deaf Individuals

Interpersonal communication relies on integrating facial and vocal signals to extract multidimensional communicative information. How the absence of audition reshapes the communicative system remains unclear. We compared the performance of deaf (N=136) and hearing (N=135) adults across multiple domains, facial identity, emotional expression, speech, and global motion, through a series of unisensory and audiovisual psychophysical tasks. The results showed that, in hearing individuals, reliance on facial versus vocal signals differed across domains. In deaf individuals, auditory deprivation did not produce uniform enhancement or impairment of visual processing. Instead, they exhibited reduced sensitivity to dynamic emotional expressions and global motion, preserved sensitivity to facial identity (both static and dynamic) and static expressions, and enhanced categorization of facial speech. Notably, sensitivity to dynamic facial expressions and global motion was correlated, and both were explained by variations in fluid intelligence. Our results reveal a domain specific framework of functional plasticity in deaf individuals, suggesting that the consequences of hearing loss are shaped both by the functional roles of audition within each domain and by broader cognitive adaptations. This framework extends the classical deficit{square}or{square}compensation perspective, deepens understanding of cognitive plasticity, and informs the development of targeted, ecologically valid accessibility and sensory{square}substitution strategies.

neuroscience↗

bioRxiv2026

Antibody maturation in germinal centers selects mutants based on BCR-antigen bond mechanical resistance

Antibody maturation in germinal centers (GCs) is traditionally viewed as a process that enhances antigen-binding affinity of B cell receptors (BCR). However, recent studies challenge this paradigm, revealing no systematic antibody affinity improvement during GC selection. Here, we investigate whether mechanical resistance of antibody-antigen bonds, rather than affinity, is the selective parameter driving GC maturation. Using biolayer interferometry measurements for assessing affinity and laminar flow chamber for mechanical resistance, we analyzed three lineages of mouse antibodies generated after immunization with ovalbumin. While affinity changes were heterogeneous, ranging from gains to losses across lineages, mechanical resistance consistently increased after maturation. Bond lifetimes under physiological forces (10-70 pN) converged to similar values across lineages, suggesting a selective pressure for mechanical stability. Functionally, NK cell activation in a surrogate in vitro ADCC assay correlated with bond lifetimes under force, but not with affinity. This indicates that lymphocytes are sensitive to the mechanical stability of antibody-antigen interactions, which may underlie GC selection. Our findings reconcile antibody maturation with the idea of enhanced binding, while aligning with the role of mechanical forces in B cell signaling and antigen uptake. These insights provide a framework for understanding GC biology and may inform the design of therapeutic antibodies.

immunology↗

bioRxiv2026

Human neuromodulatory assembloids to study serotonin signaling and disease

Neuromodulators influence critical functions of the developing human brain and regulate behavioral states. Dysfunction of neuromodulatory systems is often involved in neuropsychiatric disease and many drugs for these conditions act on these signaling pathways. Recent advances in stem cell biology have made it possible to derive a wide range of cells across the developing human nervous system in regionalized organoids and to functionally integrate them into assembloids, however they currently do not systematically incorporate neuromodulation. Here, we generated human midbrain-hindbrain organoids (hMHO) from human induced pluripotent stem (hiPS) cells and fused them with human cortical organoids (hCO) to form neuromodulatory assembloids (hNMA). We focus on serotonin (5-hydroxytryptamine, 5-HT) as one key neuromodulator and found characteristic gene expression patterns and electrophysiological properties of serotonergic neurons (5-HT neurons) in the hMHO. In hNMA, 5-HT neurons projected into hCO, released 5-HT and modulated cortical network activity. To explore the applicability of this system in human disease, we studied 22q11.2 deletion syndrome (22q11.2DS), a common microdeletion associated with high risk for neuropsychiatric disease and defects in 5-HT signaling. We found aberrant 5-HT dynamics in hNMA from patient hiPS cell lines that were rescued by administration of a selective serotonin reuptake inhibitor (SSRI). Taken together, hNMA can be used to study human 5-HT dynamics and uncover disease phenotypes which could facilitate therapeutic development.

neuroscience↗

bioRxiv2026

Myofibroblast lineage mapping and inhibiting subretinal fibrosis by targeting SMAD3 and MRTF pathways via microRNA-24 functional study

Subretinal fibrosis underlies the end-stage pathogenesis of retinal diseases including age-related macular degeneration (AMD). It can disrupt retinal structure and eventually lead to legal blindness by generating contractile force, fibrotic scarring, subretinal hemorrhage, and retinal detachment. Myofibroblasts are the predominant cells critically involved in subretinal fibrosis, however, the cellular contribution to myofibroblasts remains unclear. Here we demonstrate that multiple cell lineages, including macrophages, endothelial cells (EC), retinal pigment epithelial (RPE) cells and pericytes, significantly contribute to myofibroblasts in a laser-induced subretinal fibrosis model. We found microRNA miR-24 is significantly downregulated in the plasma of wet AMD patients. Overexpression of miR-24 represses epithelial-mesenchymal transition (EMT), endothelial-mesenchymal transition (EndMT), and the resulting fibrosis by regulating TGF-{beta}/SMAD3 and PAK4/LIMK2/MRTF pathways. Consistently, a combination of SMAD3 and MRTF inhibitors show superior efficacy to individual inhibitors in repressing fibrosis in vitro and laser-induced subretinal fibrosis in vivo. Together, these suggest the contribution of multiple cell-types in myofibroblast transformation in subretinal fibrosis, and repression of miR-24-regulated TGF-{beta}/SMAD3 and PAK4/LIMK2/MRTF pathways in multiple cell types holds therapeutic potential for treating subretinal fibrosis in AMD and other fibrotic disorders.

molecular biology↗

bioRxiv2026

CAR-T-drug conjugate against solid tumor

Chimeric antigen receptor (CAR)-T cell therapy has been clinically successful in hematologic cancers but faces challenges in solid tumors, primarily due to limited tumor infiltration, immunosuppressive tumor microenvironments (TME), and antigen heterogeneity. While combining CAR-T cell therapy with chemotherapy can enhance antitumor activity, this often leads to substantial systemic toxicity. In this study, we introduce CAR-T-drug conjugate (CAR-T-D-C), a new class of dual-functional therapeutics that effectively addresses these obstacles by integrating click chemistry for precise conjugation of cytotoxic agents onto antigen-specific CAR-T cells. By transforming the hostile TME into an ally, this approach facilitates localized delivery of cytotoxic payload directly to the tumor site, enhancing the overall effectiveness of CAR-T therapy in solid tumors. CAR-T-D-Cs with different CAR-T cell binders exhibit robust antitumor activity across diverse solid tumor models, including both human tumor xenografts and syngeneic models. Spatial transcriptomic studies reveals that CAR-T-D-C achieves improved CAR-T tumor infiltration and functional activation within the TME. Compared to conventional CAR-T therapy, CAR-T-D-C markedly enhances immune cell infiltration, augments effector functions, promotes antigen spreading, amplifies systemic immune responses, and improves overall anti-tumor immunity. CAR-T-D-C represents a versatile therapeutic concept that combines the potency of small molecule drugs and the specificity of CAR-T cells as a 2-in-1 immunochemotherapy for treatment of solid tumors.

immunology↗

bioRxiv2025

ISKNV-pORF71 hijacks outer mitochondrial membrane-localized VDAC2 to the nucleus, enhancing apoptosis by disrupting mitochondrial membrane permeability

Infectious spleen and kidney necrosis virus (ISKNV), the type species of the genus Megalocytivirus within the family Iridoviridae, is one of the most devastating pathogens affecting global teleost populations. Our previous study confirmed that ISKNV-pORF71 (p71/VP71) is a viral virulence factor by constructing a recombinant virus with ISKNV orf071 deletion (ISKNV-{Delta}71). In the present study, we further found that compared with ISKNV-WT, the ISKNV-{Delta}71 mutant is more capable of maintaining mitochondrial membrane potential, alleviating mitochondrial membrane permeabilization, preserving mitochondrial membrane integrity, sustaining lower cytochrome c release, and thereby reducing the apoptosis rate of infected cells. Further investigations demonstrated a strong interaction between p71 and the outer mitochondrial membrane (OMM)-localized voltage-dependent anion channel 2 (VDAC2). At the subcellular level, p71 and mandarin fish VDAC2 (mfVDAC2) are originally localized to the nucleus and mitochondria, respectively. However, in cells co-transfected with p71 and mfVDAC2, robust nuclear translocation of mfVDAC2 was verified. Endogenous mfVDAC2 was also confirmed to undergo nuclear translocation upon ISKNV-WT infection. In the zebrafish infection model, zebrafish VDAC2 (zfVDAC2)--but not zfVDAC-1 or zfVDAC-3--was observed to translocate into the nucleus through interaction with p71. Using CRISPR/Cas9 technology, VDAC2-knockout zebrafish were successfully constructed. Infection experiments showed that ISKNV-{Delta}71 exhibits significantly reduced lethality to both wild-type zebrafish and zfVDAC2-knockout zebrafish. In conclusion, our findings reveal that p71 exerts its function during ISKNV infection by hijacking VDAC2 into the nucleus, which alters mitochondrial membrane permeability and enhances ISKNV-induced apoptosis. The phenotypic characteristics of VDAC2 knockout (vdac-/-) zebrafish were also thoroughly analyzed and discussed. Author summaryVDAC2, a well-characterized cellular protein localized to the outer mitochondrial membrane (OMM), plays critical roles in viral pathogenesis and antiviral immune escape. Previous studies have shown that VDAC2 interacts directly or indirectly with viral proteins or functions as a functional receptor to modulate viral pathogenesis; however, few studies have demonstrated that VDAC2 is hijacked from its native OMM to other organelles. Our study here provides robust evidence that cellular VDAC2 is rerouted from its original OMM to the nucleus through interaction with ISKNV p71, thereby altering viral pathogenesis. This work offers novel insights into the role of VDAC2 in pathogen virulence. As far as we know, this is the first report demonstrating that host VDAC2 is hijacked into the nucleus by a viral protein to subsequently modulate the viral life cycle. Collectively, these findings advance our understanding of the active regulation of host functional proteins by iridoviruses.

microbiology↗