JAK-STAT pathways maintain homeostasis in immune cells (ATAC-Seq)
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ABSTRACT: Immune cells need to sustain a state of constant alertness over a lifetime. Yet, little is known about the regulatory processes that control the fluent and fragile balance that is called homeostasis. Here we demonstrate that JAK-STAT signaling, beyond its role in immune responses, is a major regulator of immune cell homeostasis. We investigated JAK-STAT-mediated transcription and chromatin accessibility across 12 mouse models, including knockouts of all STAT transcription factors and of the TYK2 kinase. Baseline JAK-STAT signaling was detected in CD8+ T cells and macrophages of unperturbed mice – but abrogated in the knockouts and in unstimulated immune cells deprived of their normal tissue context. We observed diverse transcription-regulatory programs, including gene regulation by STAT2 and IRF9 independent of STAT1. In summary, our large-scale dataset and integrative analysis of JAK-STAT mutant and wildtype mice uncovered a crucial role of JAK-STAT signaling in unstimulated immune cells, where it contributes to a poised epigenetic and transcription-regulatory state and helps prepare these cells for rapid response to immune stimuli.
Project description:Immune cells need to sustain a state of constant alertness over a lifetime. Yet, little is known about the regulatory processes that control the fluent and fragile balance that is called homeostasis. Here we demonstrate that JAK-STAT signaling, beyond its role in immune responses, is a major regulator of immune cell homeostasis. We investigated JAK-STAT-mediated transcription and chromatin accessibility across 12 mouse models, including knockouts of all STAT transcription factors and of the TYK2 kinase. Baseline JAK-STAT signaling was detected in CD8+ T cells and macrophages of unperturbed mice – but abrogated in the knockouts and in unstimulated immune cells deprived of their normal tissue context. We observed diverse transcription-regulatory programs, including gene regulation by STAT2 and IRF9 independent of STAT1. In summary, our large-scale dataset and integrative analysis of JAK-STAT mutant and wildtype mice uncovered a crucial role of JAK-STAT signaling in unstimulated immune cells, where it contributes to a poised epigenetic and transcription-regulatory state and helps prepare these cells for rapid response to immune stimuli.
Project description:Immune cells need to sustain a state of constant alertness over a lifetime. Yet, little is known about the regulatory processes that control the fluent and fragile balance that is called homeostasis. Here we demonstrate that JAK-STAT signaling, beyond its role in immune responses, is a major regulator of immune cell homeostasis. We investigated JAK-STAT-mediated transcription and chromatin accessibility across 12 mouse models, including knockouts of all STAT transcription factors and of the TYK2 kinase. Baseline JAK-STAT signaling was detected in CD8+ T cells and macrophages of unperturbed mice – but abrogated in the knockouts and in unstimulated immune cells deprived of their normal tissue context. We observed diverse transcription-regulatory programs, including gene regulation by STAT2 and IRF9 independent of STAT1. In summary, our large-scale dataset and integrative analysis of JAK-STAT mutant and wildtype mice uncovered a crucial role of JAK-STAT signaling in unstimulated immune cells, where it contributes to a poised epigenetic and transcription-regulatory state and helps prepare these cells for rapid response to immune stimuli.
Project description:JAK/STAT pathway plays important roles in controlling Drosophila intestinal homeostasis and regulating the ISC proliferation and differentiation. However,the downstream targets of its transcription factor-STAT92E remain largely unknown.To further identify the regualtory mechanisms of the JAK/STAT pathway in controlling intestinal homeostasis,we performed the ChIP-Seq assay with mouse raised STAT92E antibody using JAK/STAT signaling highly activated adult intestines.Through the ChIP assay, we have identified over 1000 significant peaks (p<0.01) around the putative targets.The well-characterized JAK/STAT downstream targets including Domeless,Socs36E,STAT92E and chinmo were identified in our ChIP assay,indicating that our experiment is workable to identify novel JAK/STAT downstream targets in adult intestines.This work will provide insights into our understanding of regulatory mechanisms of JAK/STAT signaling during Drosophila intestinal development. Identify the ChIP peaks of STAT92E antibody using JAK/STAT signaling highly actived Drosophila adult intestines, compared with input libaray as the control
Project description:Analysis of venticular myocardium from adenosine 2A receptors (A2AR) knockouts following LPS stimulation. Results provide insight into the molecular components of A2AR mediated protection, but also reveal pathogenetic components of endotoxemic myocarditis as a result of LPS exposure. These findings demonstrate that intrinsic A2AR activity exerts limited transcriptional effects in unstressed heart, modifying G-coupled cAMP/PKA signal paths. LPS-dependent injury and dysfunction is associated with profound up-regulation of inflammatory/immune processes, fibrotic and cell death paths, and NF-kB, Erk/MAPK and JAK/Stat signaling, with shifts in multiple determinants of cardiac contraction and survival. Intrinsic A2AR activity modulates key aspects of these inflammatory responses, involving MAPK, JAK/Stat and NF-kB signaling Total RNA obtained from adenosine 2A receptor knockout or wild-type murine ventricular myocardium that were treated for 24 hours with either saline or lipopolysaccharide (n=4/group).
Project description:Analysis of venticular myocardium from adenosine 2A receptors (A2AR) knockouts following LPS stimulation. Results provide insight into the molecular components of A2AR mediated protection, but also reveal pathogenetic components of endotoxemic myocarditis as a result of LPS exposure. These findings demonstrate that intrinsic A2AR activity exerts limited transcriptional effects in unstressed heart, modifying G-coupled cAMP/PKA signal paths. LPS-dependent injury and dysfunction is associated with profound up-regulation of inflammatory/immune processes, fibrotic and cell death paths, and NF-kB, Erk/MAPK and JAK/Stat signaling, with shifts in multiple determinants of cardiac contraction and survival. Intrinsic A2AR activity modulates key aspects of these inflammatory responses, involving MAPK, JAK/Stat and NF-kB signaling
Project description:JAK/STAT pathway plays important roles in controlling Drosophila intestinal homeostasis and regulating the ISC proliferation and differentiation. However,the downstream targets of its transcription factor-STAT92E remain largely unknown.To further identify the regualtory mechanisms of the JAK/STAT pathway in controlling intestinal homeostasis,we performed the ChIP-Seq assay with mouse raised STAT92E antibody using JAK/STAT signaling highly activated adult intestines.Through the ChIP assay, we have identified over 1000 significant peaks (p<0.01) around the putative targets.The well-characterized JAK/STAT downstream targets including Domeless,Socs36E,STAT92E and chinmo were identified in our ChIP assay,indicating that our experiment is workable to identify novel JAK/STAT downstream targets in adult intestines.This work will provide insights into our understanding of regulatory mechanisms of JAK/STAT signaling during Drosophila intestinal development.
Project description:The SARS-CoV-2 infection elicits widespread immunological reactions and causes severe diseases in some individuals. However, the molecular basis behind the excessive, yet non-productive immune response in COVID-19 patients with severe diseases is not fully understood. Nor is it fully known of the molecular and cellular discrepancies between severe COVID-19 and sepsis caused by other infections. To gain systems-level insights into the pathogenesis of COVID-19, we compared the blood proteome and phosphoproteome of patients under intensive care with or without SARS-CoV-2 infection, and healthy control subjects by quantitative mass spectrometry. SARS-CoV-2 infection causes global reprogramming of the kinome and the phosphoproteome, resulting in incomplete adaptive immune responses mediated by B cells and T cells, compromised innate immune response via inhibitory SIGLEC and SLAM family receptor signaling, and excessive JAK/STAT signaling. Our work identifies the kinases CK2, SYK, JAK2/3, TYK2, and the cytokine IL-12 as potential targets for the immunomodulatory treatment of severe COVID-19 and provides a valuable resource for deciphering the mechanism of pathogen-host interactions.
Project description:Treating inflammatory diseases with Janus kinase 1/2 (JAK1/2) inhibitors bears the risk that patients acquire viral infections due to unwanted immune suppression. Tyrosine kinase 2 (TYK2), a JAK family member, is required for type I interferon (IFN-α/β) signaling, but its role in type III IFN (IFN-λ) signaling is still under debate. We found that the selective TYK2 inhibitor BMS-986165 blocked potentially noxious type I IFN signaling without altering IFN-λ-mediated gene expression. We show that epithelial cells do not require TYK2 for IFN-λ-mediated signaling or antiviral protection. Lack of TYK2 diminished IFN-α-induced protection against lethal influenza virus infection of mice, but did not impair IFN-λ-mediated antiviral protection. Our findings suggest that selective TYK2 inhibitors likely represent a superior treatment option for type I interferonopathies than broadly acting JAK1/2 inhibitors, as selective TYK2 inhibitors may counteract inflammatory responses without abolishing the beneficial antiviral effects of IFN-λ.
Project description:Treating inflammatory diseases with Janus kinase 1/2 (JAK1/2) inhibitors bears the risk that patients acquire viral infections due to unwanted immune suppression. Tyrosine kinase 2 (TYK2), a JAK family member, is required for type I interferon (IFN-α/β) signaling, but its role in type III IFN (IFN-λ) signaling is still under debate. We found that the selective TYK2 inhibitor BMS-986165 blocked potentially noxious type I IFN signaling without altering IFN-λ-mediated gene expression. We show that epithelial cells do not require TYK2 for IFN-λ-mediated signaling or antiviral protection. Lack of TYK2 diminished IFN-α-induced protection against lethal influenza virus infection of mice, but did not impair IFN-λ-mediated antiviral protection. Our findings suggest that selective TYK2 inhibitors likely represent a superior treatment option for type I interferonopathies than broadly acting JAK1/2 inhibitors, as selective TYK2 inhibitors may counteract inflammatory responses without abolishing the beneficial antiviral effects of IFN-λ.
Project description:Targeted molecular therapy has yielded remarkable outcomes in certain cancers, but specific therapeutic targets remain elusive for many others. As a result of two independent RNA interference (RNAi) screens, we identified pathway dependence on a member of the JAK tyrosine kinase family, TYK2, and its downstream effector STAT1 in T-cell acute lymphoblastic leukemia (T-ALL). Gene knockdown experiments consistently demonstrated TYK2 dependence in both T-ALL primary specimens and cell lines, and a small-molecule inhibitor of JAK kinase activity induced T-ALL cell death. Activation of this TYK2-STAT1 pathway in T-ALL cell lines occurs by gain-of-function TYK2 mutations or activation of IL-10 receptor signaling, and this pathway mediates T-ALL cell survival through upregulation of the anti-apoptotic protein BCL2. These findings indicate that in many T-ALL cases, the leukemic cells are dependent upon the TYK2-STAT1-BCL2 pathway for continued survival, supporting the development of molecular therapies targeting TYK2 and other components of this pathway. Human T-ALL cell line JURKAT cells were transduced with TYK2 (TYK2#2 or #3), STAT1 (STAT1#2 or #3) or control shRNAs (GFP and Luc). Experiment was done in biological duplicate ("dup1" and "dup2") . A total of 12 RNA samples (4 control, 4 TYK2 knockdown and 4 STAT1 knockdown) were used for microarray gene expression analysis.