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Mechanical control is fundamental for cellular localization within a tissue, including for tumor-associated macrophages (TAMs). While the innate immune sensing pathways cGAS-STING and RLR-MAVS impact the pathogenesis and therapeutics of malignant diseases, their effects on cell residency and motility remain incompletely understood. Here, we uncovered that TBK1 kinase, activated by cGAS-STING or RLR-MAVS signaling in macrophages, directly phosphorylates and mobilizes Zyxin, a key regulator of actin dynamics. Under pathological conditions and in STING or MAVS signalosomes, TBK1-mediated Zyxin phosphorylation at S143 facilitates rapid recruitment of phospho-Zyxin to focal adhesions, leading to subsequent F-actin reorganization and reduced macrophage migration. Intratumoral STING-TBK1-Zyxin signaling was evident in TAMs and critical in antitumor immunity. Furthermore, myeloid-specific or global disruption of this signaling decreased the population of CD11b+ F4/80+ TAMs and promoted PD-1-mediated antitumor immunotherapy. Thus, our findings identify a new biological function of innate immune sensing pathways by regulating macrophage tissue localization, thus providing insights into context-dependent mitigation of antitumor immunity. Synopsis: Although the role of innate immune sensing pathways is well-studied in the pathogenesis of malignancies, whether they influence immune cell migration is not known. This study shows that innate immune signaling via cGAS-STING or RLR-MAVS regulates tumor-associated macrophage tissue residency through activation of the TBK1-Zyxin axis. STING signalosomes recruit and directly phosphorylate Zyxin, thus promoting its localization to focal adhesions. TBK1-Zyxin-mediated chemo-mechanical signaling enhances macrophage adhesion in response to cGAS-STING or RLR-MAVS signaling. STING-TBK1-Zyxin signaling activation in mouse intratumoral tumor-associated macrophages detains TAMs in the tumor and reduces antitumor immunity responses. Myeloid-specific or global inhibition of cGAS-STING-TBK1-Zyxin signaling facilitates antitumor immunotherapy. Innate immune sensing pathways activate the TBK1 kinase for phosphorylation of the actin dynamics regulator Zyxin to trap macrophages in the tumor. [ABSTRACT FROM AUTHOR]

Non-structural protein 2 (nsp2) exists in all coronaviruses (CoVs), while its primary function in viral pathogenicity, is largely unclear. One such enteric CoV, porcine epidemic diarrhea virus (PEDV), causes high mortality in neonatal piglets worldwide. To determine the biological role of nsp2, we generated a PEDV mutant containing a complete nsp2 deletion (rPEDV-Δnsp2) from a highly pathogenic strain by reverse genetics, showing that nsp2 was dispensable for PEDV infection, while its deficiency reduced viral replication in vitro. Intriguingly, rPEDV-Δnsp2 was entirely avirulent in vivo, with significantly increased productions of IFNB (interferon beta) and IFN-stimulated genes (ISGs) in various intestinal tissues of challenged newborn piglets. Notably, nsp2 targets and degrades TBK1 (TANK binding kinase 1), the critical kinase in the innate immune response. Mechanistically, nsp2 induced the macroautophagy/autophagy process and recruited a selective autophagic receptor, NBR1 (NBR1 autophagy cargo receptor). NBR1 subsequently facilitated the K48-linked ubiquitination of TBK1 and delivered it for autophagosome-mediated degradation. Accordingly, the replication of rPEDV-Δnsp2 CoV was restrained by reduced autophagy and excess productions of type I IFNs and ISGs. Our data collectively define enteric CoV nsp2 as a novel virulence determinant, propose a crucial role of nsp2 in diminishing innate antiviral immunity by targeting TBK1 for NBR1-mediated selective autophagy, and pave the way to develop a new type of nsp2-based attenuated PEDV vaccine. The study also provides new insights into the prevention and treatment of other pathogenic CoVs. Abbreviations: 3-MA: 3-methyladenine; Baf A1: bafilomycin A1; CoV: coronavirus; CQ: chloroquine; dpi: days post-inoculation; DMVs: double-membrane vesicles; GABARAP: GABA type A receptor-associated protein; GFP: green fluorescent protein; GIGYF2: GRB10 interacting GYF protein 2; hpi: hours post-infection; IFA: immunofluorescence assay; IFIH1: interferon induced with helicase C domain 1; IFIT2: interferon induced protein with tetratricopeptide repeats 2; IFITM1: interferon induced transmembrane protein 1; IFNB: interferon beta; IRF3: interferon regulatory factor 3; ISGs: interferon-stimulated genes; mAb: monoclonal antibody; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; MAVS: mitochondrial antiviral signaling protein; NBR1: NBR1 autophagy cargo receptor; nsp2: non-structural protein 2; OAS1: 2'-5'-oligoadenylate synthetase 1; PEDV: porcine epidemic diarrhea virus; PRRs: pattern recognition receptors; RIGI: RNA sensor RIG-I; RT-qPCR: reverse transcription quantitative polymerase chain reaction; SQSTM1: sequestosome 1; TBK1: TANK binding kinase 1; TCID50: 50% tissue culture infectious doses; VSV: vesicular stomatitis virus. [ABSTRACT FROM AUTHOR]

Immunotherapy targeting PD‐L1 is still ineffective for a wide variety of tumors with high unpredictability. Deploying combined immunotherapy with alternative targeting is practical to overcome this therapeutic resistance. Here, the deficiency of serine‐threonine kinase STK24 is observed in tumor cells causing substantial attenuation of tumor growth in murine syngeneic models, a process relying on cytotoxic CD8+ T and NK cells. Mechanistically, STK24 in tumor cells associates with and directly phosphorylates AKT at Thr21, which promotes AKT activation and subsequent PD‐L1 induction. Deletion or inhibition of STK24, by contrast, blocks IFN‐γ‐mediated PD‐L1 expression. Various murine models indicate that in vivo silencing of STK24 can significantly enhance the efficacy of the anti‐PD‐1 blockade strategy. Elevated STK24 levels are observed in patient specimens in multiple tumor types and inversely correlated with intratumoral infiltration of cytotoxic CD8+ T cells and with patient survival. The study collectively identifies STK24 as a critical modulator of antitumor immunity, which engages in AKT and PD‐L1/PD‐1 signaling and is a promising target for combined immunotherapy. [ABSTRACT FROM AUTHOR]

Lysosomal Storage Disorders (LSDs), which share common phenotypes, including enlarged lysosomes and defective lysosomal storage, are caused by mutations in lysosome-related genes. Although gene therapies and enzyme replacement therapies have been explored, there are currently no effective routine therapies against LSDs. During lysosome reformation, which occurs when the functional lysosome pool is reduced, lysosomal lipids and proteins are recycled to restore lysosome functions. Here we report that the sorting nexin protein SNX8 promotes lysosome tubulation, a process that is required for lysosome reformation, and that loss of SNX8 leads to phenotypes characteristic of LSDs in human cells. SNX8 overexpression rescued features of LSDs in cells, and AAV-based delivery of SNX8 to the brain rescued LSD phenotypes in mice. Importantly, by screening a natural compound library, we identified three small molecules that enhanced SNX8–lysosome binding and reversed LSD phenotypes in human cells and in mice. Altogether, our results provide a potential solution for the treatment of LSDs. Lysosomal storage disorders (LSDs) are severe genetic diseases currently without routine therapies. Here, the authors identified that SNX8 participates in lysosome reformation and serves as a potential drug target for new therapies to treat LSDs. [ABSTRACT FROM AUTHOR]

Liver kinase B1 (LKB1), an evolutionarily conserved serine/threonine kinase, is a master regulator of the AMPK subfamily and controls cellular events such as polarity, proliferation, and energy homeostasis. Functions and mechanisms of the LKB1-AMPK axis at specific subcellular compartments, such as lysosome and mitochondria, have been established. AMPK is known to be activated at the Golgi; however, functions and regulatory mechanisms of the LKB1-AMPK axis at the Golgi apparatus remain elusive. Here, we show that TBC1D23, a Golgi-localized protein that is frequently mutated in the neurodevelopment disorder pontocerebellar hypoplasia (PCH), is specifically required for the LKB1 signaling at the Golgi. TBC1D23 directly interacts with LKB1 and recruits LKB1 to Golgi, promoting Golgi-specific activation of AMPK upon energy stress. Notably, Golgi-targeted expression of LKB1 rescues TBC1D23 deficiency in zebrafish models. Furthermore, the loss of LKB1 causes neurodevelopmental abnormalities in zebrafish, which partially recapitulates defects in TBC1D23-deficient zebrafish, and LKB1 sustains normal neuronal development via TBC1D23 interaction. Our study uncovers a regulatory mechanism of the LKB1 signaling, and reveals that a disrupted Golgi-LKB1 signaling underlies the pathogenesis of PCH. The LKB1 signaling is differentially regulated and has distinct functions at different subcellular compartments. Tu et al reports that TBC1D23 specifically regulates Golgi-LKB1 signaling and link this pathway to neurodevelopment disorders. [ABSTRACT FROM AUTHOR]

Cyclic GMP‐AMP synthase (cGAS) monitors dsDNA in the cytosol in response to pathogenic invasion or tissue injury, initiating cGAS‐STING signaling cascades that regulate various cellular physiologies, including IFN /cytokine production, autophagy, protein synthesis, metabolism, senescence, and distinct types of cell death. cGAS‐STING signaling is crucial for host defense and tissue homeostasis; however, its dysfunction frequently leads to infectious, autoimmune, inflammatory, degenerative, and cancerous diseases. Our knowledge regarding the relationships between cGAS‐STING signaling and cell death is rapidly evolving, highlighting their essential roles in pathogenesis and disease progression. Nevertheless, the direct control of cell death by cGAS‐STING signaling, rather than IFN/NF‐κB‐mediated transcriptional regulation, remains relatively unexplored. This review examines the mechanistic interplays between cGAS‐STING cascades and apoptosis, necroptosis, pyroptosis, ferroptosis, and autophagic/lysosomal cell death. We will also discuss their pathological implications in human diseases, particularly in autoimmunity, cancer, and organ injury scenarios. We hope that this summary will stimulate discussion for further exploration of the complex life‐or‐death responses to cellular damage mediated by cGAS‐STING signaling. [ABSTRACT FROM AUTHOR]

Transforming growth factor β (TGF-β) is well known to play paradoxical roles in tumorigenesis as it has both growth-inhibitory and pro-metastatic effects. However, the underlying mechanisms of how TGF-β drives the opposing responses remain largely unknown. Here, we report that ERBB4, a member of the ERBB receptor tyrosine kinase family, specifically promotes TGF-β′s metastatic response but not its anti-growth response. ERBB4 directly phosphorylates Tyr162 in the linker region of SMAD4, which enables SMAD4 to achieve a higher DNA-binding ability and potentiates TGF-β-induced gene transcription associated with epithelial-to-mesenchymal transition (EMT), cell migration, and invasion without affecting the genes involved in growth inhibition. These selective effects facilitate lung cancer metastasis in mouse models. This discovery sheds light on the previously unrecognized role of SMAD4 as a substrate of ERBB4 and highlights the selective involvement of the ERBB4-SMAD4 regulatory axis in tumor metastasis. [Display omitted] • TGF-β inhibits cell proliferation and paradoxically promotes metastasis • ERBB4 selectively boosts TGF-β metastasis-promoting responses • ERBB4 phosphorylates SMAD4 Tyr-162 to enable SMAD4 occupancy on the EMT gene promoters • Tyr-162 phosphorylation drives TGF-β migratory responses and tumor metastasis Peihong Luo et al. describe in this paper that ERBB4 phosphorylates SMAD4 to mediate a select set of TGF-β transcriptional responses, which underscores the importance of SMAD4 tyrosine phosphorylation. Animal model data suggest that SMAD4 tyrosine phosphorylation promotes cell migration and tumor metastasis. [ABSTRACT FROM AUTHOR]

YAP/TAZ transcriptional co‐activators play pivotal roles in tumorigenesis. In the Hippo pathway, diverse signals activate the MST‐LATS kinase cascade that leads to YAP/TAZ phosphorylation, and subsequent ubiquitination and proteasomal degradation by SCFβ‐TrCP. When the MST‐LATS kinase cascade is inactive, unphosphorylated or dephosphorylated YAP/TAZ translocate into the nucleus to mediate TEAD‐dependent gene transcription. Hippo signaling‐independent YAP/TAZ activation in human malignancies has also been observed, yet the mechanism remains largely elusive. Here, we report that the ubiquitin E3 ligase HERC3 can promote YAP/TAZ activation independently of its enzymatic activity. HERC3 directly binds to β‐TrCP, blocks its interaction with YAP/TAZ, and thus prevents YAP/TAZ ubiquitination and degradation. Expression levels of HERC3 correlate with YAP/TAZ protein levels and expression of YAP/TAZ target genes in breast tumor cells and tissues. Accordingly, knockdown of HERC3 expression ameliorates tumorigenesis of breast cancer cells. Our results establish HERC3 as a critical regulator of the YAP/TAZ stability and a potential therapeutic target for breast cancer. Synopsis: The activity of the Hippo pathway transcriptional co‐activators YAP/TAZ is regulated by several ubiquitin E3 ligases, including the SCFβ‐TrCP complex. This study identifies a non‐enzymatic role of the E3 ligase HERC3 in regulation of YAP/TAZ stability in breast cancer. HERC3 can promote YAP/TAZ activation independently of its catalytic activity.HERC3 directly binds to the β‐TrCP substrate recognition subunit to block its recruitment to YAP/TAZ, thus preventing YAP/TAZ ubiquitination and degradation.HERC3 promotes breast tumorigenesis in a YAP/TAZ‐dependent manner.HERC3 expression level correlates with that of YAP/TAZ and their target genes in breast cancer. [ABSTRACT FROM AUTHOR]

Pyroptosis, a pro-inflammatory form of programmed cell death, is crucial for host defense against pathogens and danger signals. Proteolytic cleavage of gasdermin proteins B–E (GSDMB–GSDME) is well established as a trigger for pyroptosis, but the intracellular activation mechanism of GSDMA remains elusive. Here, we demonstrate that severe starvation induces pyroptosis through phosphorylation-induced activation of GSDMA. Nutrient stresses stimulate GSDMA activation via phosphorylation mediated by Unc-51-like autophagy-activating kinase 1 (ULK1). Phosphorylation of Ser353 on human GSDMA by ULK1 or the phospho-mimetic Ser353Asp mutant of GSDMA liberates GSDMA from auto-inhibition, facilitating its membrane targeting and initiation of pyroptosis. To further validate the significance of GSDMA phosphorylation, we generated a constitutively active mutant Ser354Asp of mouse Gsdma, which induced skin inflammation and hyperplasia in mice, reminiscent of phenotypes with activated Gsdma. This study uncovers phosphorylation of GSDMA as a mechanism underlying pyroptosis initiation and cellular response to nutrient stress. [Display omitted] • GSDMA is activated to induce pyroptosis upon severe starvation • Dual depletion of amino acids and ATP enables ULK1 to phosphorylate GSDMA • GSDMA suppresses gastric tumor malignancy in mouse orthotopic tumor models • Phospho-mimetic activation of GSDMA mediates skin inflammation Li et al. find that, under conditions of severe starvation, GSDMA is activated via phosphorylation and mediates pyroptosis. Data from animal models suggest that GSDMA-mediated cell death is immunogenic and may help suppress tumor malignancy. [ABSTRACT FROM AUTHOR]

Inflammasomes are intracellular signaling complexes of the innate immune system, which is part of the response to exogenous pathogens or physiological aberration. The multiprotein complexes mainly consist of sensor proteins, adaptors, and pro-caspase-1. The assembly of the inflammasome upon extracellular and intracellular cues drives the activation of caspase-1, which processes pro-inflammatory cytokines IL-1β and IL-18 to maturation and gasdermin-D for pore formation, leading to pyroptosis and cytokine release. Inflammasome signaling functions in numerous infectious or sterile inflammatory diseases, including inherited autoinflammatory diseases, metabolic disorders, cardiovascular diseases, cancers, neurodegenerative disorders, and COVID-19. In this review, we summarized current ideas on the organization and activation of inflammasomes, with details on the molecular mechanisms, regulations, and interventions. The recent developments of pharmacological strategies targeting inflammasomes as disease therapeutics were also covered. [ABSTRACT FROM AUTHOR]

The Hippo-YAP pathway responds to diverse environmental cues to manage tissue homeostasis, organ regeneration, tumorigenesis, and immunity. However, how phosphatase(s) directly target Yes-associated protein (YAP) and determine its physiological activity are still inconclusive. Here, we utilized an unbiased phosphatome screening and identified protein phosphatase magnesium-dependent 1A (PPM1A/PP2Cα) as the bona fide and physiological YAP phosphatase. We found that PPM1A was associated with YAP/TAZ in both the cytoplasm and the nucleus to directly eliminate phospho-S127 on YAP, which conferring YAP the nuclear distribution and transcription potency. Accordingly, genetic ablation or depletion of PPM1A in cells, organoids, and mice elicited an enhanced YAP/TAZ cytoplasmic retention and resulted in the diminished cell proliferation, severe gut regeneration defects in colitis, and impeded liver regeneration upon injury. These regeneration defects in murine model were largely rescued via a genetic large tumor suppressor kinase 1 (LATS1) deficiency or the pharmacological inhibition of Hippo-YAP signaling. Therefore, we identify a physiological phosphatase of YAP/TAZ, describe its critical effects in YAP/TAZ cellular distribution, and demonstrate its physiological roles in mammalian organ regeneration. This study identifies PPM1A as a phosphatase which dephosphorylates Yap, a key effector of Hippo signaling. This dephosphorylation event governs the regeneration of intestine and liver upon injury, and therefore represents a candidate therapeutic target for the treatment of Hippo signaling-related diseases such as colitis. [ABSTRACT FROM AUTHOR]

Hepatitis E virus (HEV) is one of the major etiological agents responsible for acute hepatitis. Hepatitis E virus does not replicate efficiently in mammalian cell cultures, thus a useful model that mimics persistent HEV replication is needed to dissect the molecular mechanism of pathogenesis. Here we report a genotype-3 HEV RNA replicon expressing an EGFP-Zeocin (EZ) resistant gene (p6-EZ) that persistently self-replicated in cell lines of human (Huh-7-S10-3) or hamster (BHK-21) origin after transfection with in vitro RNA transcripts and subsequent drug screening. Two cell lines, S10-3-EZ and BHK-21-EZ, stably expressed EGFP in the presence of Zeocin during continuous passages. Both genomic and subgenomic HEV RNAs and viral replicase proteins were stably expressed in persistent HEV replicon cells. The values of the cell models in antiviral testing, innate immune RNA sensing and type I IFN in host defense were further demonstrated. We revealed a role of RIG-I like receptor-interferon regulatory factor 3 in host antiviral innate immune sensing during HEV replication. We further demonstrated that treatment with interferon (IFN-α) or ribavirin significantly reduced expression of replicon RNA in a dose-dependent manner. The availability of the models will greatly facilitate HEV-specific antiviral development, and delineate mechanisms of HEV replication. [ABSTRACT FROM AUTHOR]

Occurrence of Colorectal cancer (CRC) is relevant with gut microbiota. However, role of IRF3, a key signaling mediator in innate immune sensing, has been barely investigated in CRC. Here, we unexpectedly found that the IRF3 deficient mice are hyper-susceptible to the development of intestinal tumor in AOM/DSS and Apcmin/+ models. Genetic ablation of IRF3 profoundly promotes the proliferation of intestinal epithelial cells via aberrantly activating Wnt signaling. Mechanically, IRF3 in resting state robustly associates with the active β-catenin in the cytoplasm, thus preventing its nuclear translocation and cell proliferation, which can be relieved upon microbe-induced activation of IRF3. In accordance, the survival of CRC is clinically correlated with the expression level of IRF3. Therefore, our study identifies IRF3 as a negative regulator of the Wnt/β-catenin pathway and a potential prognosis marker for Wnt-related tumorigenesis, and describes an intriguing link between gut microbiota and CRC via the IRF3-β-catenin axis. The alternative mechanisms of innate immunity in tumorigenesis of colorectal cancers are unclear. Here, the authors report a non-canonical function of IRF3, a mediator of innate immune signalling, in the suppression of colorectal tumorigenesis and this is via the inhibition of Wnt/β-catenin pathway. [ABSTRACT FROM AUTHOR]

The Hippo pathway responds to diverse environmental cues and plays key roles in cell fate determination, tissue homeostasis, and organ regeneration. Aberrant Hippo signaling, on the other hand, has frequently been implicated in diversified pathologies such as cancer and immune dysfunction. Here, we summarize the recent but rapid progress in understanding the involvement of the Hippo pathway in innate immunity, with a special focus on the intrinsic mechanisms and mutual interactions between Hippo-YAP signaling and the innate immune response and its physiological impacts on anti-microbial immunity and anti-tumor immunity. Moving forward, we believe that systematic investigations under the physiological setting are needed to draw a clearer picture of the actions of Hippo in innate immunity. [ABSTRACT FROM AUTHOR]

Pancreatic ductal adenocarcinoma (PDAC) features an immunosuppressive tumor microenvironment (TME) that resists immunotherapy. Tumor-associated macrophages, abundant in the TME, modulate T cell responses. Bone marrow stromal antigen 2-positive (BST2+) macrophages increase in Kras G12D/+; Trp53 R172H/+; Pdx1-Cre mouse models during PDAC progression. However, their role in PDAC remains elusive. Our findings reveal a negative correlation between BST2+ macrophage levels and PDAC patient prognosis. Moreover, an increased ratio of exhausted CD8+ T cells is observed in tumors with up-regulated BST2+ macrophages. Mechanistically, BST2+ macrophages secrete CXCL7 through the ERK pathway and bind with CXCR2 to activate the AKT/mTOR pathway, promoting CD8+ T cell exhaustion. The combined blockade of CXCL7 and programmed death-ligand 1 successfully decelerates tumor growth. Additionally, cGAS-STING pathway activation in macrophages induces interferon (IFN)α synthesis leading to BST2 overexpression in the PDAC TME. This study provides insights into IFNα-induced BST2+ macrophages driving an immune-suppressive TME through ERK-CXCL7 signaling to regulate CD8+ T cell exhaustion in PDAC. [Display omitted] • IFNα-induced BST2+ macrophages were highly expressed in PDAC and had a poor prognosis • BST2+ macrophages drive CD8+ T cell exhaustion through the ERK-CXCL7 pathway • PD-L1-CXCL7 antibody combination enhances anti-tumor efficacy in BST2+ macrophage tumors • PDAC mtDNA damage activates cGAS-STING-IFNα within macrophages, inducing BST2 expression Zheng et al. uncover that mtDNA damage in PDAC triggers the cGAS-STING-IFNα pathway. Therefore, IFNα-induced BST2+ macrophages drive CD8+ T cell exhaustion and pancreatic tumor growth via the ERK-CXCL7-CXCR2/AKT/mTOR pathway. [ABSTRACT FROM AUTHOR]

This correction notice addresses errors in Figure 2e of an article titled "IRF3 prevents colorectal tumorigenesis via inhibiting the nuclear translocation of β-catenin" published in Nature Communications. The errors involved duplicated images and switched images in the figure. The corrections have been made to the PDF and HTML versions of the article, and the raw data for the experiments are available as source data. The corrections do not impact the interpretation or conclusion of the experiment. Supplementary information and the authors' names are also provided. [Extracted from the article]

Abstract: TGF-β family signaling through Smads is conceptually a simple and linear signaling pathway, driven by sequential phosphorylation, with type II receptors activating type I receptors, which in turn activate R-Smads. Nevertheless, TGF-β family proteins induce highly complex programs of gene expression responses that are extensively regulated, and depend on the physiological context of the cells. Regulation of TGF-β signaling occurs at multiple levels, including TGF-β activation, formation, activation and destruction of functional TGF-β receptor complexes, activation and degradation of Smads, and formation of Smad transcription complexes at regulatory gene sequences that cooperate with a diverse set of DNA binding transcription factors and coregulators. Here we discuss recent insights into the roles of post-translational modifications and molecular interaction networks in the functions of receptors and Smads in TGF-β signal responses. These layers of regulation demonstrate how a simple signaling system can be coopted to exert exquisitely regulated, complex responses. [Copyright &y& Elsevier]

Adipose tissue macrophages (ATMs) regulate the occurrence of obesity and its related diseases. Here, we found that serine/threonine protein kinase 24 (Stk24) expression is downregulated significantly in ATMs in obese subjects or obese subjects with type 2 diabetes and mice fed a high-fat diet (HFD). We further identified that glucolipotoxicity downregulated Stk24 expression in ATMs. Stk24-deficient mice develop severe HFD-induced metabolic disorders and insulin insensitivity. Mechanistically, Stk24 intervenes in NLRP3 inflammasome assembly in ATMs by associating directly with NLRP3, decreasing interleukin-1β (IL-1β) secretion. Accordingly, Stk24 deficiency in the hematopoietic system promotes NLRP3 inflammasome activation, which contributes to exacerbation of metabolic disorders. Intriguingly, Stk24 expression correlates negatively with body mass index (BMI) and the levels of glucose, cholesterol, triglycerides, and low-density lipoprotein in human subjects. These findings provide insights into the function and clinical implications of Stk24 in obesity-mediated metabolic disorders. [Display omitted] • Glucolipotoxicity downregulates Stk24 expression in ATMs • Stk24 in ATMs negatively regulates high-fat-diet-induced metabolic disorders • Stk24 inhibits metabolic disorders by interfering with NLRP3 inflammasome activation • Stk24 binds to NLRP3 and suppresses inflammasome assembly and activation Qin et al. find that Stk24 works as an inhibitor of obesity-associated metabolic disorders by suppressing NLRP3 inflammasome activation. Reduced expression of Stk24 is associated with obesity and metabolic disorders in mice and humans. The findings provide insights into the function and clinical implications of Stk24 in obesity-mediated metabolic disorders. [ABSTRACT FROM AUTHOR]

TGF‐β controls a variety of cellular functions during development. Abnormal TGF‐β responses are commonly found in human diseases such as cancer, suggesting that TGF‐β signaling must be tightly regulated. Here, we report that protein tyrosine phosphatase non‐receptor 3 (PTPN3) profoundly potentiates TGF‐β signaling independent of its phosphatase activity. PTPN3 stabilizes TGF‐β type I receptor (TβRI) through attenuating the interaction between Smurf2 and TβRI. Consequently, PTPN3 facilitates TGF‐β‐induced R‐Smad phosphorylation, transcriptional responses, and subsequent physiological responses. Importantly, the leucine‐to‐arginine substitution at amino acid residue 232 (L232R) of PTPN3, a frequent mutation found in intrahepatic cholangiocarcinoma (ICC), disables its role in enhancing TGF‐β signaling and abolishes its tumor‐suppressive function. Our findings have revealed a vital role of PTPN3 in regulating TGF‐β signaling during normal physiology and pathogenesis. Synopsis: As abnormal TGF‐β responses are linked to human diseases such as cancer, TGF‐β signaling must be tightly regulated. This study uncovers a PTPN3 as regulator of Smurf2 binding to TβRI, a function that is abolished by hepatocarcinoma‐associated mutations. PTPN3 potentiates TGF‐β signaling independent of its phosphatase activity.PTPN3 stabilizes TGF‐β type I receptor by inhibiting its interaction with Smurf2.L232R mutation associated with intrahepatic cholangiocarcinoma interferes with the TGF‐β activatory and tumor suppressive functions of PTPN3. [ABSTRACT FROM AUTHOR]

Type I interferon (IFN)‐induced Janus kinase (JAK)–signal transducer and activator of transcription (STAT) signaling drives the expression of IFN‐stimulated genes (ISGs) to mediate antiviral response. The strength and duration of JAK‐STAT signaling are tightly regulated to ensure effective antiviral defense while avoiding pathological inflammation and autoimmunity. Here, we report that cTAZ, an isoform of the Hippo pathway effector TAZ, is transcribed by an alternative promoter. Although majority of C‐terminal sequences of TAZ is retained, cTAZ is not regulated by the Hippo signaling and does not mediate its growth‐inhibitory functions. Instead, cTAZ negatively regulates JAK‐STAT signaling by inhibiting STAT1/2 nuclear localization and ISG expression, and its expression is induced by type I IFN. Thus, cTAZ functions as a modulator of JAK‐STAT signaling and may play a role in fine‐tuning cellular antiviral response. Synopsis: JAK‐STAT signaling drives the expression of IFN‐stimulated genes to mediate antiviral immunity. A short TAZ variant, cTAZ, represses JAK‐STAT signaling and cellular antiviral responses in a Hippo pathway independent manner. cTAZ is a short TAZ variant transcribed from an alternative promoter.cTAZ is not regulated by the Hippo pathway and does not possess canonical Hippo pathway functions.cTAZ represses cellular antiviral response by inhibiting STAT1/2 dimerization and nuclear translocation. [ABSTRACT FROM AUTHOR]