Tongxiang Chen, Anthi Psoma, Shweta Mahajan, Martin Ter Beest, Peter Linders, Giulia Franciosa, Frans Bianchi, Geert van den Bogaart, Harry Warner
{"title":"Phosphorylation of VAMP3 couples IL-6 Exocytosis to dendritic cell activation.","authors":"Tongxiang Chen, Anthi Psoma, Shweta Mahajan, Martin Ter Beest, Peter Linders, Giulia Franciosa, Frans Bianchi, Geert van den Bogaart, Harry Warner","doi":"10.1242/jcs.264139","DOIUrl":"https://doi.org/10.1242/jcs.264139","url":null,"abstract":"<p><p>Adaptive immunity is critical for combating pathogens and generating immunological memory. Central to adaptive immunity are myeloid cells, which activate upon pathogen detection. Activation is essential for inflammatory cytokine release and requires a complex series of molecular events to facilitate cytokine expression. However, although the transcriptional machinery regulating cytokine expression is well defined, it is apparent that trafficking machinery also has to be re-programmed to facilitate cytokine secretion. We demonstrate through quantitative total internal-resonance fluorescence (TIRF) microscopy that short-term inflammatory stimulation with lipopolysaccharide (LPS) is sufficient to up-regulate interleukin-6 (IL-6) secretion in dendritic cells. Through bioinformatic analysis of phosphoproteomic data, we demonstrate that the activation of dendritic cells rapidly reprograms SNARE-associated trafficking machinery. We link the enhanced rate of IL-6 secretion to the phosphorylation of the SNARE protein VAMP3. This releases VAMP3 from the chaperone WDFY2, enabling the trafficking of IL-6/VAMP3+ vesicles to the plasma membrane. VAMP3 then complexes with STX4, facilitating IL-6 secretion. Finally, we found that VAMP3-dependent IL-6 secretion is polarised, reconciling findings that, in dendritic cells, IL-6-positive vesicles are non-polarised, yet VAMP3 vesicles are largely polarised.</p>","PeriodicalId":15227,"journal":{"name":"Journal of cell science","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145113165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M N Gnanapragasam, P Jiang, A R Dhara, P N Patel, M Ramamoorthy, R B Nowak, V M Fowler, J J Bieker
{"title":"EKLF/KLF1 coordinates specialized transcriptional networks required to maintain the integrity of terminal erythropoiesis.","authors":"M N Gnanapragasam, P Jiang, A R Dhara, P N Patel, M Ramamoorthy, R B Nowak, V M Fowler, J J Bieker","doi":"10.1242/jcs.264036","DOIUrl":"https://doi.org/10.1242/jcs.264036","url":null,"abstract":"<p><p>Erythroid Krüppel Like Factor (EKLF/ KLF1) is a C2H2 zinc finger transcription factor that plays a critical role in all aspects of erythropoiesis. Mutations in KLF1 lead to diverse phenotypes ranging from mild to severe anemias. Patients with a heterozygous E325K mutation (CDA type IV) exhibit impaired erythroid terminal differentiation and increased presence of binucleate erythroblasts. We previously showed that KLF1 is necessary for cell cycle exit and enucleation in mouse primary cells. In the current study we discovered that genes involved in cell motility, cell division, and mitotic pathways are all directly regulated by KLF1. Klf1-/- cells exhibit increased numbers of binucleated erythroblasts and DNA bridges, and differentiating Klf1-/- erythroblasts display an increased percentage of cytokinesis failure events and defective microtubule bundling. Klf1-/- erythroblasts produce frequent aberrant F-actin-rich membrane protrusions and anucleate cell fragments. Human CDA type IV cells exhibit similar patterns of dysregulation of cytokinesis and cell motility genes. Collectively, we show that KLF1 is necessary for maintaining the integrity of erythroid cell divisions by direct regulation of genes involved in cytokinesis and motility pathways during terminal erythroid differentiation.</p>","PeriodicalId":15227,"journal":{"name":"Journal of cell science","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145113232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nathan Palmer, Nisan Ece Kalem-Yapar, Hanna Hultén, Umur Keles, S Zakiah A Talib, Jin Rong Ow, Tommaso Tabaglio, Christine M F Goh, Li Na Zhao, Ernesto Guccione, Kui Liu, Philipp Kaldis
{"title":"Differential splice isoforms of mouse CDK2 play functionally redundant roles during mitotic and meiotic division.","authors":"Nathan Palmer, Nisan Ece Kalem-Yapar, Hanna Hultén, Umur Keles, S Zakiah A Talib, Jin Rong Ow, Tommaso Tabaglio, Christine M F Goh, Li Na Zhao, Ernesto Guccione, Kui Liu, Philipp Kaldis","doi":"10.1242/jcs.264291","DOIUrl":"https://doi.org/10.1242/jcs.264291","url":null,"abstract":"<p><p>In most mammals, the cell cycle kinase; cyclin-dependent kinase 2 (CDK2) is expressed as two major isoforms due to alternative splicing. The shorter CDK2 isoform: CDK2S, is expressed constitutively during the cell cycle and can be detected in several tissues. In contrast, the longer isoform: CDK2L, shows preferential expression in meiotically dividing cells and upon S-phase entry in the mitotic cycle. Both CDK2L and CDK2S form heteromeric complexes with cyclins A2 and E1 in vitro. However, complexes comprised of each isoform differ considerably in their kinase activity towards known CDK substrates. It is currently unknown whether the long and short isoforms of CDK2 play functionally different roles in vivo during either mitotic and meiotic divisions as conventional knockout methodology deletes both of the isoforms. Therefore, we generated mice expressing only CDK2S or CDK2L and found that both CDK2L and CDK2S are sufficient to support both mitotic and meiotic division when expressed in the absence of the other. This data contributes to the explanation of the apparent tolerance of the evolutionary loss of CDK2L expression in humans.</p>","PeriodicalId":15227,"journal":{"name":"Journal of cell science","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145113146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Louis John Kolling, Saptarsi Mitra, Catherine Anne Marcinkiewcz, Debra Ann Fadool
{"title":"The superficial tufted and mitral cell output neurons of the mouse olfactory bulb have dual roles in insulin sensing.","authors":"Louis John Kolling, Saptarsi Mitra, Catherine Anne Marcinkiewcz, Debra Ann Fadool","doi":"10.1242/jcs.264088","DOIUrl":"10.1242/jcs.264088","url":null,"abstract":"<p><p>The olfactory bulb (OB) contains multiple, parallel projection neurons to relay the nature of a stimulus. In a mouse ex vivo slice preparation, we used patch-clamp electrophysiology to measure intrinsic properties, excitability, action potential (AP) shape, voltage-activated conductances, and neuromodulation in the newly-categorized superficial tufted cells (sTCs) compared with those of mitral cells (MCs). We propose that a marked difference in voltage-dependent current represents distinct ion channel populations that affect the kinetics of action potentials, and evokes an increase in sTC firing frequency, albeit both types of projection neurons having similar AP spiking activity. Triple-colored immunofluorescence and RNA scope were used to detect co-localization of the Kv1.3 ion channel and the insulin receptor in sTCs, with ∼73% of sTCs expressing both. The sTCs were modulated by bath application of insulin - increasing AP firing frequency by 97%, attributable to an 8% decrease in the intraburst interval, and a reduction of the latency to first spike by 37%. We conclude that there may be a range of neuromodulators of sTCs that may alter excitability and fine-tune olfactory information processing or metabolic balance.</p>","PeriodicalId":15227,"journal":{"name":"Journal of cell science","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145086351","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Natasha Fahey-Lozano, Marta Portela, John E La Marca, Helena E Richardson
{"title":"RhoGEF2 overexpression induces cell competition dependent on Ptp10D, Crumbs, and the Hippo signaling pathway.","authors":"Natasha Fahey-Lozano, Marta Portela, John E La Marca, Helena E Richardson","doi":"10.1242/jcs.264377","DOIUrl":"https://doi.org/10.1242/jcs.264377","url":null,"abstract":"<p><p>In Drosophila melanogaster larval epithelial tissues, cells containing mutations in the apico-basal polarity protein, Scrib, are eliminated by cell competition when surrounded by wild-type cells. In scrib mutant cells, signaling mediated by the receptor-type tyrosine phosphatase Ptp10D upon engagement with its ligand Sas in the surrounding wild-type cells triggers cell competition via EGFR-Ras pathway inhibition and JNK pathway activation, which induces apoptosis of the mutant cells. Here, we investigate whether overexpression of RhoGEF2 (RhoGEF2OE), which induces Rho signaling and affects actin cytoskeleton regulators, acts similarly to Scrib depletion in cell competition. We show that RhoGEF2OE cells are eliminated when surrounded by wild-type cells, and Ptp10D knockdown increases RhoGEF2OE clone growth. Mechanistically, in clones moderately overexpressing RhoGEF2OE, Ptp10D knockdown rescued cell elimination by reducing Hippo signaling. Additionally, mutations in the apical cell polarity protein, Crb, partially rescued the elimination of RhoGEF2OE clones. In this setting, in which RhoGEF2OE is highly overexpressed, JNK and Hippo signaling were elevated while EGFR-Ras signaling was reduced, and crb loss normalized these pathways. Thus, RhoGEF2OE leads to clone elimination dependent on Crb, Ptp10D, and Hippo signaling.</p>","PeriodicalId":15227,"journal":{"name":"Journal of cell science","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145086219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Emeline Durel, Nathalie Bécot, Mathieu Pinot, Laurent Chesneau, Thierry Pécot, Roland Le Borgne
{"title":"Regulation of cell shape and mechanics by Rho GEF/GAP in a proliferative epithelial tissue.","authors":"Emeline Durel, Nathalie Bécot, Mathieu Pinot, Laurent Chesneau, Thierry Pécot, Roland Le Borgne","doi":"10.1242/jcs.264163","DOIUrl":"https://doi.org/10.1242/jcs.264163","url":null,"abstract":"<p><p>Epithelial cell shape results from the combination of intrinsic properties of the actomyosin cytoskeleton and extrinsic properties due to physical interactions with neighbouring cells, in particular at the adherens junctions. In the Drosophila epidermis, non-muscle myosin type II (MyoII) is a key force regulator for the control of cell shape. MyoII is activated by Rho GTPases, themselves activated by guanine nucleotide exchange factors (GEFs) and inhibited by GTPase activating proteins (GAPs). Here, we screened 28 Drosophila GAPs and 36 GEFs on the pupal notum to identify regulators of MyoII distribution and dynamics, epithelial cell shape and cytokinesis. Among the candidates identified, we show that PlexA, a transmembrane GAP regulates the shape of sensory organ precursors in a cell-autonomous manner, and that RhoGEF Cyst acts downstream of Crumbs and trimeric G proteins Gβ13F/Gγ1 to regulate junctional MyoII and adherens junctions remodelling during interphase and cytokinesis, in a non-cell autonomous manner. This study provides a comprehensive basis of GEFs and GAPs impacting epithelia homeostasis, and shed light on the mechanisms linking actomyosin contractility, cell shape regulation and cell junction dynamics.</p>","PeriodicalId":15227,"journal":{"name":"Journal of cell science","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145080781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Allele-specific conformational rescue of KIF1A(T99M) by genetic suppressors in a C. elegans model of KIF1A-associated neurological disorder.","authors":"Zihan Chen, Yongping Chai, Zhengyang Guo, Xuanyu Fu, Wei Li, Jinxiang Zhang, Guangshuo Ou, Hui Wang","doi":"10.1242/jcs.264216","DOIUrl":"https://doi.org/10.1242/jcs.264216","url":null,"abstract":"<p><p>KIF1A-associated neurological disorder (KAND) arises from mutations in the microtubule motor KIF1A, disrupting synaptic vesicle transport. Here, we investigate the pathogenic T99M substitution in KIF1A's P-loop, which induces steric hindrance, impairing ATP/ADP coordination and motor activity. Using CRISPR-engineered C. elegans expressing the homologous UNC-104(T95M) mutation, we conducted forward genetic screens and identified recurrent intragenic suppressors (T95V/I) that restored animal motility and synaptic vesicle distribution. Molecular dynamics simulations revealed that replacing methionine with valine/isoleucine alleviated steric clashes in the nucleotide-binding pocket and stabilized Mg²⁺-ATP coordination. Biochemical assays showed that T95V/I partially recovered microtubule gliding velocity and processivity, demonstrating that even modest motor reactivation mitigates neuronal dysfunction. Inspired by prior success with fisetin in rescuing the KIF1A R11Q variant, we propose allele-specific conformational stabilization as a therapeutic strategy for KAND. Our findings highlight the structural plasticity of motor domain and provide a framework for precision therapies targeting pathogenic variants through genetic suppressors.</p>","PeriodicalId":15227,"journal":{"name":"Journal of cell science","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145080770","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Priyanka Verma, Bharat Yalavarthi, Swati Bhattacharyya, Dinesh Khanna, Johann E Gudjonsson, Lam C Tsoi, Rebecca Wells, Rebecca L Ross, Natalia Riobo-Del Galdo, Francesco Del Galdo, Sean M Fortier, Maria E Teves, John Varga, Dibyendu Bhattacharyya
{"title":"Morphological reprogramming of primary cilia length mitigates the fibrotic phenotype in fibroblasts across diverse fibrotic conditions.","authors":"Priyanka Verma, Bharat Yalavarthi, Swati Bhattacharyya, Dinesh Khanna, Johann E Gudjonsson, Lam C Tsoi, Rebecca Wells, Rebecca L Ross, Natalia Riobo-Del Galdo, Francesco Del Galdo, Sean M Fortier, Maria E Teves, John Varga, Dibyendu Bhattacharyya","doi":"10.1242/jcs.264191","DOIUrl":"https://doi.org/10.1242/jcs.264191","url":null,"abstract":"<p><p>Myofibroblast differentiation, shared across fibrotic diseases, is marked by actin polymerization and assembly of αsmooth muscle actin (αSMA) stress fibers. Primary cilia (PC) are solitary membrane-bound organelles present on the majority of cells. PC length regulation is a complex process influenced by actin polymerization. We discovered that fibroblasts from diverse fibrotic conditions display significantly reduced PC length ex vivo. Treatment of healthy fibroblasts with profibrotic TGF-β1 induced PC shortening, while silencing ACTA2 in systemic sclerosis (SSc) skin fibroblasts caused PC elongation. Importantly, we found that PC length was negatively correlated with αSMA levels in TGF-β1-treated healthy fibroblasts and pharmacologically dedifferentiated myofibroblasts. Our results suggest that during the fibrotic response, higher-order actin polymerization, along with microtubule destabilization by tubulin deacetylation, drives PC length shortening. In contrast, PC length elongation via stabilization of microtubule polymerization mitigates the fibrotic phenotype in fibrotic fibroblasts. These results reveal a potential link between PC length and fibroblast activation conserved across multiple fibrotic conditions. Our observations suggest that modulation of PC length might represent a novel therapeutic strategy for SSc and other treatment-resistant diseases associated with fibrosis.</p>","PeriodicalId":15227,"journal":{"name":"Journal of cell science","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145075072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"MLL/WDR5 complex promotes recruitment of KIF2C to midbody to ensure MT depolymerization and furrow initiation during cytokinesis.","authors":"Avishek Kataria, Neeraja Hemalatha, Akash Chinchole, Shweta Tyagi","doi":"10.1242/jcs.263622","DOIUrl":"https://doi.org/10.1242/jcs.263622","url":null,"abstract":"<p><p>Mixed-lineage leukemia (MLL) protein is a well-characterised epigenetic regulator whose non-canonical activities remain underappreciated. MLL has been shown to localize on the midbody and loss of this protein leads to binucleation. However, the critical role of the MLL complex in midbody formation remains underexplored. Here, we further characterize the localization of MLL and its associated protein WDR5 to the midbody. Loss of MLL/WDR5 results in defective midbody formation, which displays a wide midzone-like microtubule structure, along with chromosome bridges, resulting in binucleated cells. We show that MLL and WDR5 interact with kinesin 13 motor-KIF2C, and target it to the midbody. The depolymerase activity of KIF2C promotes correct localization of centralspindlin complex, compaction of midzone MTs, and finally, timely furrow initiation. Thus, we identify a previously unrecognized role for MLL and KIF2C in cytokinesis regulation. Together with earlier findings, this implicates them in the regulation of actin-microtubule cytoskeleton interface-pathways frequently altered in oncogenesis.</p>","PeriodicalId":15227,"journal":{"name":"Journal of cell science","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145075387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Luis Fernando Rubio-Atonal, Jinlan Chang, Julie Jacquemyn, Isha Ralhan, Iset Ilarraza, Maria S Ioannou
{"title":"Glutamate decreases oxidative stress and lipid droplet formation in astrocytes.","authors":"Luis Fernando Rubio-Atonal, Jinlan Chang, Julie Jacquemyn, Isha Ralhan, Iset Ilarraza, Maria S Ioannou","doi":"10.1242/jcs.263983","DOIUrl":"https://doi.org/10.1242/jcs.263983","url":null,"abstract":"<p><p>Astrocytes degrade fatty acids in response to glutamate while reducing the abundance of lipid droplets. But how glutamate regulates lipid droplets in astrocytes is unclear. Here we show that glutamate decreases the amount of reactive oxygen species which in turn, reduces autophagy and the amount of lipids in need of storage in lipid droplets. This decrease in lipid droplets and reactive oxygen species occurs independent of glutamate import through excitatory amino acid transporters (EAATs). However, activation of AMPK, downstream of EAATs, further promotes a decrease in lipid droplets. Glutamate also increases the pool of fused mitochondria capable of maintaining enhanced fatty acid metabolism. Our work reveals how astrocytic metabolism is regulated by glutamate that can serve to coordinate astrocyte physiology with neuronal activity.</p>","PeriodicalId":15227,"journal":{"name":"Journal of cell science","volume":" ","pages":""},"PeriodicalIF":3.6,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145075299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}