Biology subjects

Liu, J.

Publications and source records attributed to Liu, J..

At least 109 records · Page 6Linked to original sources

bioRxiv2026

LightAlign: a lightweight pairwise aligner for memory-constrained HiFi read assembly

IntroductionCurrent de novo genome assembly tools often demand substantial memory resources, and their execution typically relies on high-performance computing (HPC) clusters. This dependency limits their use in resource-constrained settings. Furthermore, mainstream third-generation sequencing assembly and alignment tools usually require explicit detection of overlap regions between reads, a process that often entails significant computational and storage overhead. ResultsTo address this issue, we developed LightAlign, a lightweight alignment tool for HiFi data that innovatively uses sequence-derived fuzzy features and reduces the peak memory usage during overlap detection. ConclusionsWhen combined with miniasm, LightAlign generated bacterial draft assemblies while maintaining peak memory usage below 1 GB and completed overlap generation for the tested eukaryotic datasets within 1.88 GB RAM.

bioinformatics↗

bioRxiv2026

The S1B-Targeting PEDV Neutralizing Antibody C62 Prematurely Activates S-trimer and Mimics Receptor Function

Porcine epidemic diarrhea virus (PEDV) causes devastating enteric disease in piglets, yet the mechanistic basis of antibody-mediated neutralization remains poorly understood. Here, we determined the structure of PEDV HNXX-strain spike domain B (S1B) simultaneously bound by C62, a neutralizing porcine monoclonal antibody against PEDV G2 strains, and N34, a non-neutralizing porcine PEDV antibody. The structure reveals that C62 targets a conserved, cryptic epitope that is accessible only when S1B adopts an "up" conformation. Functionally, we showed that C62 has substantially stronger activity than N34 in triggering S-trimer disassembly and inducing the formation of proteinase K-resistant, post-fusion-like S2 structures. Despite the weaker triggering activity of N34, both C62 and N34 can function as artificial receptors. Notably, although the C62 epitope is conserved across both G1 and G2 strains, C62 exhibits G2-strain-biased neutralizing activity. We further showed that differences in cell-surface membrane fusion activity among PEDV spikes correlate with distinct viral entry pathways and are jointly determined by the S1A and S1B sequences. Together, our findings identify a strain-specific vulnerable site on the PEDV S-trimer and provide insight into how cell-surface membrane fusion activity may influence viral entry pathway selection and antibody neutralization efficacy.

microbiology↗

bioRxiv2026

Epithelial-Intrinsic Alterations and Maladaptation to Luminal Metabolites Underlie Persistent Crohn's Disease Pathogenesis

In patients with Crohns disease, the noninflamed intestinal epithelium exhibits inflammation-like transcriptional signatures that persist even during clinical remission. However, it is unclear whether this signature is due to sustained environmental triggers or to the epitheliums intrinsic immunological adaptions. To disentangle environmental and cell-intrinsic effects on disease signatures, we used noninflamed intestinal tissue biopsies from patients with active and inactive Crohns disease, as well as control donors, to generate donor-matched organoids enriched for intestinal epithelial cells. We collected single-cell RNA-seq and single-cell ATAC-seq data from intestinal tissues, and from their matched organoids before and after stimulation with luminal metabolites of patients. This approach allowed us to distinguish between the effects of extrinsic factors and the intrinsic alterations that persist when cells are removed from their local environment. We found that organoid cells retained epithelial-autonomous disease phenotypes, even when derived from patients in remission, whereas signatures from tissue cells showed evidence of immune- and microbial-epithelial crosstalk. In contrast to healthy control organoids, organoids from Crohns disease patients exhibited selective activation of disease-associated transcriptional changes and environment-responsive inflammatory chromatin remodeling after exposure to patient-derived luminal metabolites. Overall, our study suggests that disease-associated epithelial states are shaped by both cell-intrinsic dysregulation and microenvironmental cues.

immunology↗

bioRxiv2026

PSMε controls skin commensal CD8+ T cell activation

Upon skin colonization, the prevalent human skin commensal S. epidermidis can elicit a CD8+ T cell response that protects against pathogens or clears tumors. The microbial features that drive this response are undefined, limiting our ability to understand and predict commensal-immune crosstalk and to engineer potent commensal-derived immunotherapies. To uncover these microbial features, we harnessed both the natural variation in CD8+ T cell induction across primary human isolates of Staphylococcus and our ability to genetically manipulate these strains. Stimulatory strains exhibit increased quorum sensing activation, which turns on a unique commensal-associated gene family, called phenol-soluble modulin {varepsilon} (PSM{varepsilon}), that is required for CD8+ T cell activation. PSM{varepsilon} not only acts as the immunodominant CD8+ T cell antigen but also enhances cross-presentation in an antigen-agnostic manner. Co-delivering PSM{varepsilon} promotes CD8+ T cell priming to an exogenous antigen via a mechanism that is independent of formyl peptide receptor and co-stimulatory receptor upregulation. Thus, we demonstrate that specific aspects of microbiome-immune crosstalk can be distilled to molecular components, which engage in previously undescribed mechanisms and can be harnessed for immunotherapy without requiring live bacterial colonization.

immunology↗

bioRxiv2026

Transforming clinical apheresis waste into a renewable source of patient-derived CD34+ hematopoietic stem cell biobank for beta-hemoglobinopathy research and therapeutic discovery

Background aimsThe development of next-generation therapies for sickle cell disease (SCD) and beta thalassemia (beta thal), including fetal globin-inducing small molecules and gene therapy approaches, depends on patient-derived CD34+ hematopoietic stem and progenitor cells (HSPCs) for discovery and preclinical validation, but commercial vendors stock only healthy donor material and disease-specific banks hold limited inventories. Recent US Food and Drug Administration and National Institutes of Health guidance favoring human cell-based methods over animal testing underscores the value of authentic patient cells. Methods: Over 14 months we recovered, purified, and biobanked CD34+ HSPCs from clinical apheresis product waste and mobilized peripheral blood (PB) otherwise discarded after clinical procedures, using immunomagnetic selection adapted for hemoglobinopathy specimens; a microfluidic technology was evaluated separately. We quantified yield and purity for bead-selected material and cell number and viability for the microfluidic pilot; engraftment was tested in NBSGW mice. Results: Immunomagnetic selection recovered a median of 4.71 x 106 CD34+ cells from just 1 to 2 mL of apheresis product waste, comparable to the 6.0 x 106 cells from a 10 to 40 fold larger volume of PB waste, with similar purity across sources and diagnoses. Because apheresis product waste is far more concentrated, it reaches equivalent yields without the density-gradient steps required for PB waste, approximately halving processing time. Recovered cells engrafted NBSGW mice, confirming preserved repopulating capacity. The microfluidic pilot (two patients, 11 specimens) recovered 2.17 x 106 CD34+ cells per specimen at greater than 90% viability and purity. Conclusions: A center with existing apheresis infrastructure can reproducibly recover, bank, and distribute research-grade patient CD34+ HSPCs, addressing a recognized gap in the hemoglobinopathy pipeline. HighlightsO_LIClinical apheresis waste is used to generate a single-center biobank of high-quality, research-grade CD34+ HSPCs from patients with sickle cell disease and beta-thalassemia. C_LIO_LIConcentrated apheresis waste matches large-volume PB waste in CD34+ yield and purity. C_LIO_LIMicrofluidic enrichment recovers CD34+ cells at >90% viability and purity across 2 patients. C_LIO_LIRecovered CD34+ HSPCs engraft mice and form erythroid cells, preserving function. C_LI

pharmacology and toxicology↗

bioRxiv2026

Host cell identity shapes the replication and evolution of Drosophila C virus

RNA viruses encounter diverse cellular environments within their hosts, yet how different host cell types influence viral evolution remains poorly understood. Here, we investigated the replication and experimental evolution of Drosophila C virus (DCV) in glial, mesodermal, and hemocyte-derived S2 cells. Mesodermal cells supported substantially higher viral RNA accumulation, viral protein production, and infectivity than glial or S2 cells, demonstrating pronounced cell type-dependent permissiveness. Comparative transcriptomic and proteomic analyses revealed distinct host responses to DCV infection despite the common mesodermal origin of mesodermal and S2 cells. Functional analyses showed that RNA interference, cGAS-STING signaling, viral binding and entry, and cellular ATP abundance could not account for the enhanced replication of DCV in mesodermal cells, whereas S2 cells displayed stronger cGAS-STING and JAK- STAT responses. Serial passage of DCV for 15 generations in mesodermal or S2 cells resulted in rapid phenotypic adaptation, with evolved viruses exhibiting improved replication in the corresponding cell type without altering infectivity in adult flies. Genome sequencing revealed distinct evolutionary patterns between nonstructural and structural protein-coding regions. Nonstructural proteins remained highly conserved with limited evidence of parallel evolution, whereas structural proteins accumulated more mutations and exhibited broader signatures of positive selection. A recurrent VP3 mutation (G8089A; R270H) independently emerged in three S2-passaged lineages, representing the only mutation consistently associated with adaptation to a specific cell type. Structural modeling suggested that this substitution is unlikely to substantially alter VP2-VP3 interactions, implying more subtle effects on capsid function. Together, our findings demonstrate that different Drosophila cell types impose distinct intracellular selective pressures that shape DCV replication and evolutionary trajectories, highlighting host cell identity as an important determinant of RNA virus evolution.

microbiology↗

bioRxiv2026

Sleep reactivation of positive self-evaluation reveals neural-evaluative alignment that varies with depressive symptoms

Positive self-evaluation underpins resilience and mental health, yet how to enhance positive self-evaluation and the underlying neurocognitive mechanisms remain poorly understood. Existing data mostly examined self-evaluative processing of the wakeful minds, with the role of sleep remain unexplored. Here, we demonstrated that reactivation of positive self-evaluation during sleep revealed fine-grained neural-evaluative alignment that varies with depressive symptoms. We found that targeted reactivation of positive personality traits during non-rapid eye movement (NREM) sleep enhanced positive self-evaluation, but this benefit diminished with elevated depressive symptoms. Moreover, cueing positive traits during NREM sleep elicited trait-specific, 11-16 Hz EEG sigma power-based neural representations that aligned with post-sleep positive self-evaluative representational structures, as revealed by representational similarity analyses. Notably, individuals with elevated depressive symptoms exhibited weaker neural-evaluative representational alignments, identifying a maladaptive self-evaluative processing that bridges across sleep and wakefulness states. These findings provide mechanistic insights on how fine-grained neural-evaluative alignment can substantiate positive self-evaluation, and why it was disrupted as depressive symptoms increased. HighlightsO_LIPositive-trait reactivation during NREM sleep enhances positive self-evaluation C_LIO_LIThis behavioral benefit decreases as depressive symptoms increase C_LIO_LISleep cueing evokes trait-specific sigma-band neural representations C_LIO_LINeural-evaluative alignment weakens as depressive symptoms increase C_LI

neuroscience↗

bioRxiv2026

Catch-bond engineering surpasses high-affinity maturation for T cell receptor therapies against solid tumors

The sensitivity of T cell receptors (TCRs) has traditionally been attributed to their affinity, a principle that has long underpinned both T cell biology and TCR engineering. Currently, high-affinity maturation remains the predominant strategy employed to enhance TCR sensitivity; however, this approach has been associated with severe off-target toxicities in clinical settings. In this study, using the only FDA-approved TCR-T therapy as a clinical reference, we demonstrate that force-induced catch bonds, rather than static affinity, primarily determine TCR sensitivity and facilitate the development of more effective TCR engineering strategies. Among polar and charged amino acids, histidine was determined to be the most effective residue for pinpointing engineering hotspots. TCRs engineered to form catch bonds exhibited superior performance compared to the FDA-approved TCR subjected to high-affinity maturation, improving the efficacy of TCR-T cell therapies against solid tumors without eliciting off-target toxicity or alloreactivity. Mechanistically, a correlation was observed between TCR sensitivity and the strength of catch bonds, whereas no such relationship was found with affinity. The duration of T cell-tumor cell interactions, immunological synapse formation, and the intensity of subsequent signaling are governed by catch bonds rather than by affinity. Structural and computational investigations have demonstrated that force-induced reconfiguration of the ligand-receptor interface, along with the formation of a novel hydrogen bond network, augments the specificity of interactions between the TCR and antigenic peptides. Furthermore, bispecific T cell engagers utilizing the TCR scaffold also formed catch bonds with tumor antigens, indicating intrinsic mechanosensory properties of the extracellular domains of TCRs and suggesting a novel therapeutic modality based on catch-bond-engineered TCRs.

immunology↗

bioRxiv2026

Deep Mutational Scanning of the GPCR Rhodopsin Reveals Pleiotropic Mutational Effects and Their Roles in Modulating Light Sensitivity

Biophysical pleiotropy, the phenomenon in which a mutation affects multiple protein properties, underlies many genetic diseases and shapes protein evolution, yet remains poorly understood, limiting synthetic biology and therapeutic development. Although extensively studied in soluble proteins, little is known about how pleiotropic effects shaped the evolution of receptor protein functions. Here, we developed a cell-based assay designed to assess pleiotropic effects in G protein-coupled receptors (GPCRs), the largest receptor class in eukaryotes. Because our assay design allows for multiple GPCR molecular phenotypes (basal activity, ligand-dependent signaling, and cellular receptor abundance) to be simultaneously assessed, we applied it to study rhodopsin, a visual GPCR that evolved high light sensitivity by maximizing light-driven responses while minimizing thermally driven noise. To investigate this, we integrated our assay with deep mutational scanning of relevant rhodopsin domains to test the impacts of [~]2,000 single-residue substitutions in rhodopsin across all three molecular phenotypes ([~]6,000 measurements). By analyzing these data in the context of rhodopsins protein structures, we discovered complex pleiotropic effects that act asymmetrically to impose joint constraints, restricting mutational tolerance in rhodopsins retinal binding pocket and G protein interaction interface. A dose-response analysis of rhodopsin signaling revealed that these pleiotropic constraints arise from the dual functions of its chromophore, which acts as an agonist upon light-driven isomerization but also an inverse agonist in darkness. Because these constraints reflect mechanistically driven limitations in the evolution of receptor signaling, these findings reveal a role for biophysical pleiotropy in shaping the sensory capabilities of receptor proteins. Significance StatementUnderstanding how genetic variation impacts protein function is an important but challenging area of research as many mutations are pleiotropic, simultaneously affecting multiple protein properties, including structure, stability, and activity. Previously, genetic screens have systematically mapped pleiotropic effects in soluble proteins, but transmembrane receptor proteins embedded in cellular membranes are much more difficult to assay. These are key receptors that convert environmental stimuli into appropriate physiological responses. Here, we present a systematic study of pleiotropic effects within the receptor responsible for dim-light vision in vertebrates, revealing how light sensitivity can be mediated through differential conformational states of its chromophore. This is important not only for understanding how receptors evolved enhanced capabilities, but also for the development of tunable protein systems.

evolutionary biology↗

bioRxiv2026

The endosomal trafficking protein Myopic differentially regulates Drosophila C virus infection in cultured cells and adult flies

Positive-sense RNA viruses extensively exploit host membrane trafficking pathways to establish intracellular replication organelles required for efficient viral replication. However, the contribution of endosomal trafficking proteins to infection by Drosophila C virus (DCV), a natural dicistrovirus of Drosophila melanogaster, remains poorly understood. Here, we investigated the role of Myopic (Mop), a conserved ESCRT-associated endosomal trafficking protein, during DCV infection. Knockdown of mop in cultured S2 cells significantly increased DCV RNA and viral protein accumulation without affecting viral binding or entry, indicating that Mop restricts DCV replication at a post-entry stage. In addition, depletion of mop altered the intracellular distribution of viral proteins, suggesting that Mop may influence the organization of DCV-associated intracellular membrane compartments. Unexpectedly, fat body-specific knockdown of mop in adult flies produced the opposite phenotype, resulting in reduced viral accumulation and prolonged survival following systemic DCV infection. This antiviral phenotype was not associated with enhanced activation of the STING or JAK-STAT pathways. Instead, transcriptomic and proteomic analyses revealed extensive remodeling of gene and protein expression, including altered abundance of proteins associated with autophagy and RNA interference. Together, our findings identify Mop as a previously unrecognized regulator of DCV infection and reveal distinct cell-autonomous and systemic functions of this conserved trafficking protein. These results highlight the importance of endosomal trafficking in antiviral defense and demonstrate that host membrane trafficking factors can exert fundamentally different effects on virus infection at the cellular and organismal levels.

microbiology↗

bioRxiv2026

Sex-Specific Modulation of Gene Expression by 17beta-Estradiol in Human Meniscal Cells: Pathways to Targeted Osteoarthritis Therapies

Osteoarthritis (OA) disproportionately affects women, and estrogen has been implicated in cartilage and joint homeostasis, yet its effects on meniscal fibrochondrocytes (MFCs), and whether those effects differ by sex, remain poorly defined. We reanalyzed a publicly available RNA-sequencing dataset (Gene Expression Omnibus, GSE199087) comprising human MFCs from a male and a female donor treated with 17{beta}-estradiol (E2) or vehicle. Differential expression, Gene Set Enrichment Analysis, Enrichr, and iLINCS were integrated to identify the transcriptional programs modulated by E2 in each sex. In female MFCs, E2 upregulated pathways governing DNA replication, cell-cycle progression, and genomic maintenance (e.g., MCM8, BRCA1, RAD51), while downregulating inflammatory and extracellular matrix-degrading genes, including MMP1, IL12A, CXCL12, and MYD88. In male MFCs, E2 instead upregulated chromatin remodeling and developmental signaling programs, led by SRCAP, ERCC6, and NOTCH1, and downregulated antigen presentation and mitochondrial genes. These divergent responses indicate that E2 engages distinct, sex-specific transcriptional programs in MFCs, with the female profile favoring proliferation and matrix preservation. Although derived from a limited sample and therefore hypothesis-generating, these findings nominate candidate mechanisms underlying sex differences in meniscal biology and OA susceptibility, and warrant validation in larger, sex-balanced cohorts. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/740612v1_ufig1.gif" ALT="Figure 1"> View larger version (33K): org.highwire.dtl.DTLVardef@16026fforg.highwire.dtl.DTLVardef@1a048acorg.highwire.dtl.DTLVardef@3246corg.highwire.dtl.DTLVardef@4c598b_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioinformatics↗

bioRxiv2026

Electron counting enables cryo-electron ptychography for near-atomic-resolution cryo-electron microscopy

Cryo-electron ptychography is an emerging technique for studying radiation-sensitive biological specimens, developed from four-dimensional transmission electron microscopy (4D-STEM). Although ptychography has achieved ultrahigh resolution beyond conventional transmission electron microscopy limits for radiation-resistant samples, its application to frozen hydrated biological specimens currently remains at sub-nanometer resolution. Here we overcome this limitation by implementing electron counting with a hybrid-pixel detector, establishing key technical foundations for near-atomic-resolution cryo-ptychography. This counting approach significantly improves weak signal detection in convergent-beam electron diffraction, enabling ptychographic reconstruction at doses below 1 e-/[A]{superscript 2}. Additionally, we found beam-induced motion is effectively eliminated within single scans, suggesting conventional cryoEMs dose-fractionation approach may need reevaluation. Demonstrating high contrast under both low-dose and tilted conditions, along with achieving 3.59 [A] resolution for the [~]700 kDa T20S proteasome, we validate cryo-electron ptychography as a viable general imaging modality that could complement or surpass conventional phase-contrast cryoEM methods.

biophysics↗

bioRxiv2026

Hidden genetic diversity in 320 nearly-complete East Asian genome assemblies

East Asian populations, representing over 20% of the global population, remain critically underrepresented in human genomic studies, limiting our understanding of population-stratified genetic variation and its implications for health and disease. Here we present the first phase of the Asian Pan-Genome project (APG), comprising 320 nearly complete, fully phased haploid genome assemblies from 160 East Asian individuals. These assemblies achieve unprecedented quality, with an average contig N50 of 144.3 megabase pairs and an average quality value of 64.5. Leveraging these superior assemblies, we reveal previously uncharacterized diversity in human repeatome, including population-stratified patterns in centromere satellites and rDNA arrays. Compared to existing global human genome assemblies, the newly generated genomes supplement 152 million base pairs of novel sequences, 355 gene gains, 18,300 structural variation loci and 26 large euchromatic inversions missing from current human pangenomes. We perform population stratification analyses of structural variations, and further resolve the structural haplotypes of complex genomic regions such as Major Histocompatibility Complex and Survival Motor Neuron loci across global pangenomes, exemplifying tandem-duplicate and inversion-rich complex locus architectures in the human genome, respectively. This resource provides a critical foundation for human genetic studies, especially for East Asian populations, promoting more accurate variant discovery, reducing bias, and ultimately advancing the equity and efficacy of genomic medicine.

genomics↗

bioRxiv2026

The Live Concert of Brains: Performer-Audience Neural Coupling Links Ensemble Coordination to Shared Audience Integration

Collective social events often require coordinated action by one group to become shared experience in another, yet how this transformation is organized across multiple brains remains unclear. Live music provides a tractable model of this problem because ensemble coordination, performer-audience alignment, and shared audience integration unfold within the same event. Here we tested whether performer-audience neural coupling acts as a cross-role neural interface linking ensemble coordination to shared audience integration. We recorded brain activity from a nine-person live performance system, consisting of a fixed three-performer ensemble and four independent audience groups, using synchronized multi-device functional near-infrared spectroscopy hyperscanning across live trio performance sessions. Inter-brain neural coupling was analyzed across three relational layers: performer-performer (PP), performer-audience (PA), and audience-audience (AA) coupling. Behavioral ratings showed strong affective engagement and shared evaluative alignment. Neural coupling during live performance was not expressed as a diffuse increase across channel pairs, but was organized into task-sensitive relational components with interpretable PC-corr network modules. Crucially, path-based mediation analyses revealed that PA components statistically bridged PP coordination and AA coupling, yielding multiple complete and partial PP [->] PA [->] AA pathways. Brain-behavior analyses further suggested that mediation-related PA components were linked to shared performance evaluation and emotional alignment. These findings identify performer-audience coupling as a cross-role neural interface through which coordinated production becomes linked to shared collective reception. Significant StatementHow coordinated actions become shared experiences is a major problem in social neuroscience, yet most studies examine pairs of people. Using live music as a model of group interaction, we found that brain-to-brain alignment was organized across social roles rather than arising as a uniform response to the same event. Performer-audience alignment occupied a bridging position between coordination within the ensemble and integration within the audience. This identifies a systems-level architecture through which collective action may become linked to collective experience. The framework moves multi-brain research beyond dyads and offers a general approach for studying classrooms, public speaking, theater, rituals, and team events, where one group generates structured behavior that another group jointly receives and interprets.

neuroscience↗

bioRxiv2026

Spatium: A Protein Language Foundation Model for Spatial Proteomics

Spatial proteomics provides single-cell protein measurements under highly constrained and heterogeneous protein panels across datasets, resulting in limited and partially overlapping measurement spaces for cellular characterization. Existing analyses predominantly rely on statistical or task-specific modeling, while learning scalable representations of spatial protein data remain underexplored. This gap motivates the need for models that can learn stable representations of cellular identity from constrained protein measurements. Here we introduce Spatium, a protein language foundation model trained on over 51 million cells across multiple spatial proteomics platforms. Spatium learns intrinsic co-expression hierarchies that capture cell identity in a manner robust to panel composition and measurement scale. Spatium builds a generalizable representation of cell states grounded in biologically interpretable protein expression patterns. We demonstrate that Spatium learns biologically meaningful cell representations across multiple downstream tasks. Spatium recovers accurate cell identities with marker expression patterns consistent with known biology and reveals functionally distinct spatial microenvironments characterized by coherent marker enrichment signatures. It further enables reconstruction of missing protein measurements while preserving biologically meaningful expression patterns. Across these analyses, Spatium demonstrates stable and interpretable performance with lightweight task-specific adaptation, highlighting the robustness of the learned representations across diverse biological and experimental contexts.

bioinformatics↗

bioRxiv2026

IL-13 Induces a Tuft Cell-Intrinsic CD45 Checkpoint to Limit Intestinal Type 2 Immunity

Tuft cells initiate intestinal type 2 immunity, yet the mechanisms that restrain excessive tuft cell activation remain poorly understood. Here, we identify the receptor tyrosine phosphatase CD45 (Ptprc), previously considered a hematopoietic marker, as a regulator of intestinal tuft cell function. CD45 expression is restricted to a subset of tuft cells and is induced by helminth infection and IL-13. Epithelial-specific deletion of Ptprc activated a tuft cell inflammatory program, promoted an epithelial inflammatory state, and increased eosinophil accumulation at homeostasis. During Heligmosomoides polygyrus bakeri infection, CD45 deficiency enhanced ILC2 and Th2 responses and reduced parasite burden, demonstrating that epithelial CD45 limits type 2 immunity in vivo. Accordingly, in intestinal organoids, CD45 was dispensable for IL-13-driven tuft cell differentiation but restrained IL-13-responsive transcriptional programs. Mechanistically, CD45-deficient tuft cells exhibited altered protein abundance of STAT5 and IL17RB, implicated in tuft cell immune regulation. Together, these findings identify CD45 as a tuft cell-intrinsic regulatory checkpoint that restrains intestinal type 2 immunity through an IL-13-induced negative-feedback circuit.

immunology↗

bioRxiv2026

Imaging-Based Age- and Sex-specific Cardiovascular and Skeletal Phenotypes in Fbn1C1041G/+ Mice

Marfan syndrome is a multisystem connective tissue disorder with age-dependent and sex-dependent phenotypic variability. This study characterized early cardiovascular, valvular, transmitral flow, and skeletal changes in Fbn1C1041G/+ mice. Male and female wild-type and Fbn1C1041G/+ mice were examined from 4 to 20 weeks of age. Transthoracic echocardiography was used to measure aortic root and ascending aortic diameters, anterior mitral leaflet length, and mitral inflow Doppler parameters. Lateral X-ray imaging was used to quantify kyphosis angle. Fbn1C1041G/+ mice of both sexes developed progressive aortic dilation, with earlier and broader aortic root involvement in males and delayed annular dilation in females. Anterior mitral leaflet elongation was detected from 8 weeks in males and at 20 weeks in females. In contrast, reduced E-wave velocity and E/A ratio were present from 4 weeks in both sexes, without changes in A-wave velocity. Kyphosis was detectable earlier in females than in males. These findings show that early Fbn1-related phenotypes follow organ-specific and sex-dependent temporal patterns, supporting age-resolved and sex-stratified assessment in preclinical Marfan syndrome studies.

pathology↗

bioRxiv2026

Lipid Imbalance Generates Golgi Whorls that Sequester Small GTPases

Small GTPases are generally viewed as organizers of organelle identity, with different families recruited to specific membranes by compartment-selective targeting mechanisms. Here, we identify a membrane state that reverses this relationship. Excessive peptide S-palmitoylation at Golgi generates multilamellar, filipin-poor whorls that recruit ARF, Rab, and Rho family GTPases normally associated with distinct cellular compartments. The whorls simultaneously excluded Golgi transmembrane residents, coat proteins, ER proteins, a GPI-anchored protein, and other palmitoylated proteins, demonstrating that they were selective membrane compartments rather than nonspecific protein aggregates. Preventing myristoylation of ARF6 or geranylgeranylation of Rab11a strongly reduced recruitment, whereas prenylation alone was insufficient, indicating recognition of a composite membrane-targeting code. Lowering cellular cholesterol promoted whorl formation, whereas cholesterol supplementation suppressed it. Chemically distinct lipid perturbations generated GTPase-positive Golgi whorls, suggesting convergence on a shared membrane-remodeling state. As whorls accumulated, endocytic recycling and anterograde trafficking declined, survival signaling decreased, and viability became poorly reversible. These findings show that lipid imbalance can redirect small GTPases across normal organelle boundaries, converting Golgi-derived membranes into selective sinks for trafficking regulators.

cell biology↗