Biology subjects

Pan, H.

Publications and source records attributed to Pan, H..

At least 19 recordsLinked to original sources

bioRxiv2026

The MASLD-causing E167K variant of TM6SF2 is degraded by the ubiquitin ligase RNF5

The TM6SF2 E167K loss-of-function variant is one of the most penetrant genetic risk factors for metabolic dysfunction-associated steatotic liver disease (MASLD), including progression to cirrhosis and hepatocellular carcinoma. Here we show that TM6SF2 E167K is recognized and degraded by the ER-associated degradation pathway, and identify RNF5 as the ubiquitin ligase tagging TM6SF2 E167K, providing a rational target for MASLD therapy.

biochemistry↗

bioRxiv2026

WRN deficiency generates oncogenic rearrangements at TA-rich tandem repeats

Werner syndrome, a premature-aging disorder caused by inherited loss of the WRN helicase, predisposes to a narrow set of cancers, including melanoma and sarcoma, through mechanisms that have been unclear. WRN resolves the secondary structures that TA-dinucleotide repeats form, a role established for the expanded repeats of mismatch-repair-deficient cancers. We show that WRN loss also destabilizes native, unexpanded TA-rich tandem repeats, which become fragile sites where chromosomes break and rearrange. In melanoma these rearrangements recurrently produce an identical 15.7Mb-long deletion that transcriptionally activates TERT, the earliest driver of these tumors, and separately disrupt tumor suppressors such as CDKN2A/B and NF1. The same class of rearrangement occurs in WRN-deficient cancers of other types. WRN deficiency is thus a source of instability at TA-rich tandem repeats that generates oncogenic rearrangements.

cancer biology↗

bioRxiv2026

ScreenDMT reveals metabolites replicably associated with sleep disorders across three human cohorts

The robust replication of scientific findings across independent studies is essential, yet it remains challenging in high-dimensional biological datasets. A critical aspect of true replication requires detecting not only the repeated presence but also the consistent direction of an effect. Traditional methods for evaluating replication often ignore effect directionality or lack adequate statistical power when adjusting for multiple comparisons. To address this, we extend the directional MaxP test (DMT) and our screening-integrated procedure, ScreenDMT, to evaluate directional replication across an arbitrary number of independent studies. We mathematically prove ScreenDMT's validity for an arbitrary number of studies when the studies' sample sizes grow unbounded. Through extensive simulation studies, we demonstrate that ScreenDMT effectively controls error rates, such as the false discovery rate (FDR), in finite sample sizes and yields higher statistical power than competing methods especially for three studies. We applied the extended ScreenDMT to untargeted blood metabolomics profiles across three diverse human cohorts - ARIC (N=1,337), MESA (N=1,874), and HCHS/SOL (N=6,180) - to discover replicable biomarkers for dichotomous insomnia, long sleep, short sleep, and excessive daytime sleepiness (EDS). We found low levels of cortisol to be replicably associated with EDS, and high levels of n-formylmethionine to be associated with long sleep. Furthermore, directional pathway analysis revealed that low levels of xanthine metabolites are replicably associated with insomnia. These convergent findings validate ScreenDMT as a powerful methodology for simultaneous multi-cohort replication and offer robust insights into the metabolic signatures underlying sleep disorders across diverse populations.

bioinformatics↗

bioRxiv2026

Integrative proteomic analysis and molecular dynamics simulations of ANKLE2 reveal mechanisms of microcephaly

ANKLE2 is a scaffolding protein with crucial roles in neuroprogenitor cell division and embryonic brain development. Pathogenic variants in ANKLE2 cause primary microcephaly, a congenital disorder characterized by impaired neurodevelopment. Nonetheless, the underlying dysfunction of ANKLE2 is not understood. Here, we define the ANKLE2 protein interaction landscape, which includes cell division proteins and novel microcephaly candidates in the APC (anaphase-promoting complex). Analysis of six pathogenic variants reveals changes in this interactome that likely result in microcephaly. Using molecular simulations, we identify the structural consequences of five pathogenic substitutions, including disruption of important helical structures. Combined, these techniques suggest loss of interaction with the PP2A (protein phosphatase 2A) complex is a common mechanism for ANKLE2 pathogenesis. Phosphoproteomics reveals widespread alterations in ANKLE2- and PP2A-dependent phosphorylation of cell division proteins. Together, our integrative proteomics and simulation approach improves the molecular understanding of ANKLE2 function and its pathogenic changes in primary microcephaly.

systems biology↗

bioRxiv2026

The Hao-Fountain syndrome gene USP7 restricts neurotropic orthoflavivirus entry through cell intrinsic control of endosomal dynamics

Neurodevelopmental disorders are increasingly associated with immune phenotypes, including autoinflammation, immunodeficiency, and increased susceptibility to severe infection. To determine whether neurodevelopmental disorders-associated genes exert immune functions, we performed an arrayed siRNA screen targeting 28 genes with nonredundant cellular roles and assessed their effects on Zika virus (ZIKV) infection and innate immune pathways. We identified hits that intrinsically restrict ZIKV infection and modulate inflammatory pathways following infection. We further characterized the antiviral activity of the Hao-Fountain syndrome gene USP7, which potently restricts selected neurotropic orthoflaviviruses. USP7 inhibits ZIKV internalization before viral membrane fusion and genome release into the cytoplasm. Because USP7 plays a role in endosomal tubulation and recycling, we investigated whether endosomal recycling pathways restrict ZIKV infection. We identified the USP7-regulated E3 ubiquitin ligase TRIM27, as well as the recycling-associated Rab GTPases RAB11 and RAB35, as potent regulators of ZIKV infection. Infection assays using cell lines expressing pathogenic USP7 variants and primary fibroblasts from individuals with Hao-Fountain syndrome demonstrated that disease-associated USP7 mutations impair its antiviral activity and increase permissivity to ZIKV infection. These findings are consistent with recent case reports of unusually severe viral infection during early life in individuals with Hao-Fountain syndrome. Collectively, our study identifies endosomal recycling pathways as important intrinsic restriction mechanisms against neurotropic orthoflaviviruses and nominates pathogenic USP7 variation as a candidate inborn error of immunity.

microbiology↗

bioRxiv2026

Population genomics of the inquiline social parasite Acromyrmex insinuator and its leaf-cutting ant hosts A. echinatior and A. octospinosus reveals cryptic differentiation and reduced efficiency of selection in the parasite

Inquiline social parasites usurp colonies of closely related host ants to exploit their social resources. They are almost invariably rare, patchily distributed and difficult to study. Here we build on almost 25 years of Panamanian fieldwork on the social parasite Acromyrmex insinuator and its A. echinatior and A. octospinosus hosts, to perform a population genomic analysis to test hypotheses that have been suggested to shape the evolution of inquiline social parasites: 1. Do these parasites indeed have extremely reduced effective population size? 2. Does extant genetic variation at coding and non-coding sites carry signatures of erosion of adaptive potential? 3. Has A. insinuator become fully reproductively isolated from its sympatric hosts and how closely related are its primary and secondary host? We show that the two host species are completely distinct and that genetic diversity and effective population size of the social parasite are dramatically reduced despite ongoing but very minor recent gene flow between the parasite and its primary host A. echinatior. We also demonstrate that non-synonymous codon-sites evolved at rates nearly indistinguishable from synonymous codon-sites. This indicates a significant reduction in the efficiency of natural selection consistent with inquiline social parasite lineages generally being evolutionarily short-lived. We finally uncover clear sub-structure in the parasite population, with two genetically distinct lineages occurring in sympatry in the Panama Canal Zone, and with significant differences in their likelihood of exploiting the secondary host A. octospinosus and the primary host from which they segregated sympatrically ca. 1 MYA.

genomics↗

bioRxiv2026

An Inverse Transwell Assay for Airway Mucus Barrier Function Reveals both Virus- and Mucin-Specific Impacts on Infection

Respiratory viruses are a significant cause of morbidity and mortality world-wide and an important trigger of acute exacerbation in chronic lung disease. Secreted airway mucus - a front-line defense system against respiratory virus infection - is largely composed of glycosylated mucins that promote virus trapping via steric and adhesive interactions. Still, the degree to which mucus can trap specific viruses is unclear. Further, mucin expression is altered in chronic lung disease with undefined impacts on host susceptibility to infection. Here, we devised an inverse Transwell assay (ITA) to specifically probe the barrier function of mucus towards infection without the confounding effects of ongoing mucus secretion and transport on viral dynamics. Using the ITA, we assessed the barrier function of human airway epithelial (HAE) culture-derived mucus towards influenza (IAV), rhinovirus (RV), adenovirus, and parainfluenza virus. Results showed differences in mucus penetration efficiency between viruses, with IAV being the most inhibited relative to no mucus controls. Notably, IAV and RV penetration efficiency was similar between normal mucus and mucus sourced from an in-vitro model of asthmatic epithelium. To further explore the role of specific mucins during infection, we employed CRISPR/Cas9-modified HAE cultures lacking either MUC5B or MUC5AC expression. Direct infection in these cultures with IAV yielded higher viral titers compared to control HAE, suggesting both MUC5B and MUC5AC contribute to antiviral defense. Application of mucus harvested from specific mucin-knockout or control HAE in the ITA revealed that while RV penetration was similar across conditions, IAV was more efficient in breaching MUC5AC-depleted gels. Subsequent biophysical analysis of these mucus gels revealed a larger pore structure in the absence of MUC5AC. Together, these data indicate mucus-mediated restriction is virus dependent and highlight the contribution of MUC5AC to mucus structure and antiviral capabilities. Further, they establish the ITA as a tunable platform enabling investigation into mucus penetration by diverse viruses and the effects of altered mucus composition on barrier function. Clinical RelevanceMucus composition is altered in chronic lung disease states and during inflammation with unknown consequences on its barrier function towards respiratory virus infection. Using an inverse Transwell assay, we describe virus-specific kinetics through mucus representative of health and disease and identify a critical role for MUC5AC in defense towards influenza A virus. This work can inform future strategies to improve infection prevention or mucus targeted therapies, and may help explain differences in susceptibility to viral infections across the population.

microbiology↗

bioRxiv2026

High glucose confers senescence resistance via GLUT1 epigenetic rewiring to blunt immunotherapy responses in esophageal squamous cell carcinoma

Therapeutic resistance and undefined predictive biomarkers severely hinder the clinical popularization of immunotherapy in esophageal squamous cell carcinoma (ESCC). Herein, we identify the glucose transporter 1 (GLUT1) as a critical determinant of immunotherapy resistance. Elevated expression of GLUT1 correlates with poor immunotherapy response and unfavorable prognosis in ESCC patients. GLUT1 deletion or inhibition enhances CD8 T cell infiltration and cytotoxicity, and sensitizes ESCC tumors to anti-PD-1 (-PD1) therapy. Importantly, dietary glucose restriction exhibits equivalent antitumor efficacy to GLUT1 inhibition when combined with -PD1. Mechanistically, GLUT1 establishes a positive feedback loop with HAT1 and FOXM1, which epigenetically remodels chromatin accessibility to suppress tumor cell senescence, thereby impeding CD8 T cell-mediated antitumor immunity. Our findings highlight GLUT1 as a predictive biomarker of immunotherapy resistance and suggest dietary glucose restriction as a viable strategy to potentiate immunotherapy efficacy in ESCC. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=188 HEIGHT=200 SRC="FIGDIR/small/738372v1_ufig1.gif" ALT="Figure 1"> View larger version (52K): org.highwire.dtl.DTLVardef@c2c5d5org.highwire.dtl.DTLVardef@14a34c7org.highwire.dtl.DTLVardef@cf05e4org.highwire.dtl.DTLVardef@18bc354_HPS_FORMAT_FIGEXP M_FIG C_FIG SHORT SUMMARYDong et al. identify glucose transporter 1 (GLUT1) as a predictor of poor response to immunotherapy in esophageal squamous cell carcinoma. GLUT1 promotes immune evasion by forming a positive feedback loop with the HAT1/FOXM1 anti-senescence axis, thereby epigenetically remodeling chromatin accessibility. GLUT1 inhibition or dietary glucose restriction restores CD8 T-cell-mediated antitumor immunity and improves the efficacy of anti-PD-1 therapy in preclinical models.

cancer biology↗

bioRxiv2026

AI-enabled Spatial Profiling of Circulating Tumor-Immune Ecosystems Predicts Patient Outcomes Across Cancers

Circulating tumor cells (CTCs) and immune cells form dynamic multicellular ecosystems in blood, but their spatial organization and clinical relevance have not been systematically characterized. We developed the Cell and Cluster Identification Program (CCIP), an artificial intelligence-based framework that analyzes routine multiplex immunofluorescence blood scans to segment cells, identify CTCs and five immune lineages with high accuracy, and quantify multicellular clusters and tumor-immune interactions. Applying CCIP to 2,693 blood scans from 1,399 patients, we profiled over 60 million cells (>7 million multi-cell clusters) and linked imaging-derived features to patient outcomes. Correlated with circulating-tumor DNA mutation burdens, a 14-feature image model predicted overall survival in breast cancer, outperformed clinicopathologic variables and CTC enumeration, and generalized to prostate cancer. Prognostic imaging signatures were also associated with therapy response-related progression-free survival as well as with single-cell RNA sequencing-derived immune suppression states, connecting circulating tumor-immune architecture with systemic immune dysfunction.

cancer biology↗

bioRxiv2026

X chromosome inactivation as a novel mechanism for chondrogenesis

X chromosome inactivation (X-inactivation) is generally regarded as a dosage-compensation mechanism restricted to female mammals. Here we show that BMP signaling induces X-inactivation through upregulation of Xist and promotes chondrogenesis in both sexes. Remarkably, augmented BMP signaling induced ectopic X-inactivation: transiently inactivating both X chromosomes in females and one in males in a tissue-specific manner. In cranial neural crest cells, ectopic X-inactivation suppressed X-linked gene Tmsb4x, leading to ectopic cartilage formation. Genetic reduction of Xist or pharmacological restoration of the Tmsb4x product suppressed this phenotype. Moreover, we identified ectopic X-inactivation in SOX9-positive chondroprogenitors during wild-type forelimb development in both sexes. Inhibition of X-inactivation disrupts proximodistal limb patterning ex vivo. These findings establish X-inactivation as a signaling-dependent developmental mechanism linking chromosome-scale gene alterations to skeletal fate specification.

Developmental Biology↗

bioRxiv2026

Distinct senescent β-cell senotypes differentially drive islet aging and dysfunction

Biological aging greatly impacts the bodys ability to handle glucose, and represents a major risk factor the development and progression of type 2 diabetes (T2D). Nonetheless, despite advances in cellular senescence research and the development of new senolytic therapies, the heterogeneity of cellular senescence in the human endocrine pancreas, as well as its roles in normal aging, remains to be elucidated at the single-cell level. Here, we performed single-cell-resolved spatial proteomics and transcriptomics on intact pancreas from 26 donors (ages 20-80) and multiplexed single-cell RNA sequencing and functional assays on dispersed islets from 14 donors (ages 34-69). We identify two discrete SnC subpopulations distinguished by relative expression of CDKN1A and CDKN2A. CDKN1A senescent cells (SnCs) exhibit loss of {beta}-cell identity, impaired insulin secretion, and a proinflammatory SASP associated with increased islet immune infiltration. In contrast, CDKN2A SnCs retain transcriptional identity and functional competence, with lower inflammatory signaling. Together, these findings identify heterogeneous and functionally divergent senotypes in the human pancreas, distinguishing an adaptive (CDKN2A) from a maladaptive (CDKN1A) senescence program, thus providing a mechanism-guided framework for senescence-targeted therapies in T2D.

cell biology↗

bioRxiv2026

A Genetically Engineered Human Organoid Model Reveals Distinct Genetic and Epigenetic Barriers of Lineage Plasticity in Early PDAC Transformation

The lack of accurate, human-based models recapitulating early-stage pancreatic ductal adenocarcinoma (PDAC) has hindered therapeutic development. Using pluripotent stem cell-derived pancreatic progenitor organoids, we established a human PDAC model that faithfully reproduces the genetic, epigenetic, and transcriptomic trajectory of tumor initiation and progression in vitro, validated against clinical datasets and histopathology. We demonstrate that CDKN2A loss, nearly universal in patients but dispensable in mouse models, is essential for neoplastic transformation when combined with KRAS and TP53 mutations, while SMAD4 loss promotes tumor progression. Multi-omics profiling reveals epigenetic repression of pancreatic lineage program during PDAC initiation, alongside oncogenic AP-1-driven chromatin remodeling. Notably, we identify TET1 suppression as a mechanistic link between oncogenic ERK signaling and the hypermethylation and silencing of essential pancreatic transcription factors. This model captures the genetic and epigenetic determinants of human PDAC, reveals antagonism between oncogenic and lineage restriction programs, and supports TET-based lineage restoration as a promising early intervention strategy for high-risk individuals.

cancer biology↗

bioRxiv2026

A bivalent lysine-acetylated small-molecule binding site in MYC

MYC is an important, yet challenging target in oncology as it lacks traditional druggable pockets. Here, we show that two regions of MYC, the basic-helix-loop-helix (bHLH) domain, and extended MYC Box II (eMBII) come together to form a bivalent, high-affinity small-molecule MYC inhibitor (MYCi) binding site. CRISPR-tiling mutagenesis identified mutations in the vicinity of the eMBII and bHLH regions that together confer MYCi resistance. Importantly, acetylation of K148 in eMBII, which is essential for MYC oncogenicity in vivo, enhanced MYCi binding affinity and is predicted to increase the structural order of this region. Furthermore, MYCi selectively modulated the expression of the same genes regulated by lysine-acetylated MYC in cancer cells. These studies provide a rationale for selective targeting of acetylated, oncogenic MYC with small molecules.

cancer biology↗

bioRxiv2026

Cell Type Architecture and Positional Gene Gradients in an Adult Animal at Subcellular Resolution

The spatial organization of cell types and gene expression underlies tissue architecture and organismal physiology. However, resolving complete cellular and molecular landscapes within a three-dimensional context remains challenging, particularly in organisms with high cellular heterogeneity and complex geometry. Here, we developed a semi-supervised workflow to reconstruct high-resolution three-dimensional spatial transcriptomic models of the planarian Schmidtea mediterranea at single-cell resolution. Planarians are basal bilaterians capable of regenerating body structures after injury. Our reconstruction maps the distribution of cell types and spatially patterned gene expression across the intact organism and identifies 119 candidate positional control genes (PCGs). These genes are expressed across muscle, neural, and epidermal populations. Functional perturbation of selected candidates, including pitx3, ptpn11, pi4ka, upf3b, and cul1, revealed roles in regeneration following injury. In addition, we identify intestinal cells as prominent components of the microenvironment surrounding adult tgs1 pluripotent stem cells (neoblasts). Together, these results demonstrate the utility of three-dimensional spatial transcriptomic reconstruction for mapping cellular architecture and positional gene regulation in complex adult organisms.

developmental biology↗

bioRxiv2026

4D Single-Cell Spatial Transcriptomics Reveals Dynamic Morphogenetic Gradients and Regenerative Domains in Planarians

Regeneration relies on precise spatiotemporal gene expression and cellular responses to establish tissue identity and body patterning. Using high-resolution Stereo-seq (715 nm) on 353 sections from 16 whole animals at 8 regeneration timepoints, we constructed a 4D spatiotemporal transcriptomic map of planarian regeneration. Our analysis captured 36 refined cell types from 3,508,004 segmented cells, enabling genome-wide transcriptional imputation of gene expression dynamics across body axes at cellular, tissue, and organismal scales. We identified dynamic positional gradients and distinct spatially distributed cell types during regeneration, including an injury-induced Anterior Regenerative Zone (ARZ). The ARZ exhibited enriched positional signals in epidermal, muscle, and neural cells and was regulated by Mediator 8, which is crucial for polarity remodeling and blastema formation. This study provides a comprehensive spatial molecular and cellular map of regenerative processes, highlighting injury-induced spatial domains and key regulatory factors in planarian regeneration. We also provide an interactive web portal, offering a valuable resource for exploring and analyzing regeneration mechanisms in a spatiotemporal context.

developmental biology↗

bioRxiv2026

BEACON: predicting side effects and therapeutics outcomes to drugs by Bridging knowlEdge grAph with CONtextual language model

Biomedical knowledge graphs encode millions of relationships between drugs, proteins, pathways, and diseases, yet translating this structured knowledge into accurate predictions remains challenging. Existing deep learning approaches, including graph neural networks and knowledge graph embeddings, assign fixed representations to entities regardless of biological context, limiting their ability to capture how the same gene or pathway functions differently across scenarios. These methods also lack interpretability and often fail when applied to novel drugs outside their training distribution. Here we present BEACON (Bridging knowlEdge grAph with CONtextual language model), a framework that transforms knowledge graphs into contextual sentence representations processable by language models. BEACON converts biomedical entities into tokens and relationships into syntactic dependencies, creating "sentence trees" that preserve graph structure while enabling contextual processing. A visibility matrix ensures that attention patterns respect the underlying knowledge graph topology, and a perturbation-based evaluation module identifies the specific genes, enzymes, and pathways driving each prediction. We demonstrate BEACONs versatility through two clinically important applications. For drug sensitivity prediction in cancer cell lines, BEACON achieves 0.941 AUROC and Spearman {rho} = 0.919, outperforming existing methods (DrugCell, DeepCDR and DeepTTA). For drug-drug interaction (DDI) prediction, BEACON achieves 0.964 AUROC on the TwoSIDES benchmark and 0.84 AUROC on temporally held-out FDA adverse event data (2013-2023), demonstrating robust generalization to newly approved drugs. Applying BEACON to the BTK inhibitor acalabrutinib revealed that predicted interactions are enriched for drugs metabolized by CYP3A enzymes (OR = 3.01, P = 4.3 x 10-), a mechanism validated through network proximity analysis. BEACON provides a unified, interpretable approach to knowledge graph-enhanced biomedical prediction.

bioinformatics↗

bioRxiv2026

Covalent Leader Peptide Probes Enable Proteome-Level Mapping of RiPP Enzymes beyond Biosynthetic Gene Clusters

Genome-based analyses have enabled widespread discovery and biosynthetic annotation of ribosomally synthesized and post-translationally modified peptides (RiPPs) pathways, yet often fail to capture all participating enzymes, particularly those encoded outside canonical biosynthetic gene clusters. In this study, leveraging the central role of leader peptides (LPs) in RiPP enzyme-substrate recognition, we developed a substrate-guided chemical-proteomic strategy using covalent LP probes to directly identify LP-binding enzymes from native proteomes. Using the LctA-LctM and PatE-LynD systems, we demonstrate that LP probes carrying a photocrosslinker engage enzymes at their authentic LP-recognition sites while preserving full catalytic competence. Application of this strategy to a model strain Streptomyces sparsogenes uncovered lanthipeptide synthetases encoded outside canonical biosynthetic gene clusters and revealed graded cross-cluster activities among multiple RiPP pathways. This work establishes a proof-of-concept model platform for proteome-level discovery of LP-binding RiPP enzymes and highlights cross-cluster enzymatic crosstalk as a latent mechanism for structural diversification.

biochemistry↗

bioRxiv2025

Nuclear activities and interactome of the NS5 protein of Tick-Borne Encephalitis Virus

Orthoflaviviruses are RNA viruses responsible for significant diseases in humans, domesticated animals and wildlife. Their NS5 protein is central in viral replication, functioning both as an RNA-dependent RNA polymerase and a methyltransferase, while also modulating cellular processes, including the interferon response. Although viral replication is cytoplasmic, the NS5 protein of several mosquito-borne orthoflaviviruses cycles between the cytoplasm and the nucleus of infected human cells. However, the nuclear localization and function of NS5 of tick-borne orthoflaviviruses, such as tick-borne encephalitis virus (TBEV), remained poorly understood. Microscopy analysis and cell fractionation revealed that the NS5 protein of TBEV localized to both the cytoplasm and nucleoplasm of infected cells. Mutagenesis studies identified critical residues required for its nuclear targeting. Mutating these residues in a TBEV replicon abolished viral replication. Immunoprecipitation-mass spectrometry analyses performed in two human cell lines infected with TBEV recovered 352 NS5 partners. Among them, 187 were nuclear or partially nuclear. By integrating our interactome data with that of Powassan virus (POWV), another tick-borne orthoflavivirus, we refined a list of 20 high-confidence NS5 partners, including splicing factors and chromatin modulators. Functional analysis revealed that seven of these nuclear partners significantly modulated viral replication, further underscoring the importance of nuclear NS5 in the viral life cycle. Our work advances our understanding of the nuclear function of the NS5 proteins of tick-borne orthoflaviviruses. ImportanceTick-borne orthoflaviviruses are emerging globally, spreading across Europe, Asia, and North America, where they infect humans, domesticated animals, and wildlife. These viruses produce a protein called NS5, which drives viral replication and helps evade the innate immune response. We observed that the NS5 protein of tick-borne encephalitis virus (TBEV) localized both in the cytoplasm and nucleoplasm of infected human cells. We identified the specific residues responsible for its nuclear addressing and showed that it interacts with numerous nuclear proteins, including some involved in regulating gene expression. Seven of these nuclear partners significantly influenced viral replication, highlighting the importance of NS5s nuclear activity. This work sheds light on how tick-borne orthoflaviviruses manipulate host cells, deepening our understanding of their replication strategies.

microbiology↗