Browse
Submit Data
Databases
API
Help

Dataset Information

34 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Microbial recognition by GEF-H1 controls IKK? mediated activation of IRF5.

ABSTRACT: During infection, transcription factor interferon regulatory factor 5 (IRF5) is essential for the control of host defense. Here we show that the microtubule-associated guanine nucleotide exchange factor (GEF)-H1, is required for the phosphorylation of IRF5 by microbial muramyl-dipeptides (MDP), the minimal structural motif of peptidoglycan of both Gram-positive and Gram-negative bacteria. Specifically, GEF-H1 functions in a microtubule based recognition system for microbial peptidoglycans that mediates the activation of IKK? which we identify as a new upstream IKK?/? and IRF5 kinase. The deletion of GEF-H1 or dominant-negative variants of GEF-H1 prevent activation of IKK? and phosphorylation of IRF5. The GEF-H1-IKK?-IRF5 signaling axis functions independent of NOD-like receptors and is critically required for the recognition of intracellular peptidoglycans and host defenses against Listeria monocytogenes.

SUBMITTER: Zhao Y

PROVIDER: S-EPMC6430831 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Microbial recognition by GEF-H1 controls IKKε mediated activation of IRF5.

Zhao Yun Y Zagani Rachid R Park Sung-Moo SM Yoshida Naohiro N Shah Pankaj P Reinecker Hans-Christian HC

Nature communications 20190322 1

During infection, transcription factor interferon regulatory factor 5 (IRF5) is essential for the control of host defense. Here we show that the microtubule-associated guanine nucleotide exchange factor (GEF)-H1, is required for the phosphorylation of IRF5 by microbial muramyl-dipeptides (MDP), the minimal structural motif of peptidoglycan of both Gram-positive and Gram-negative bacteria. Specifically, GEF-H1 functions in a microtubule based recognition system for microbial peptidoglycans that m ...[more]

PMID: 30902986

Similar Datasets

GEF-H1-IRF5 mediated gene expression changes in BMDM by MDP recognition

Project description:The transcription factor IRF5 is essential for immune defense against pathogens. Here, the authors show that the microtubule-associated factor GEF-H1 plays a critical role in host defense against Listeria monocytogenes in macrophages via activation of the IRF5 kinase IKKe

2019-04-02 | GSE126749 | GEO

GEF-H1-IRF5 mediated gene expression changes in BMDM by MDP recognition

Project description:GEF-H1-IRF5 mediated gene expression changes in BMDM by MDP recognition

| PRJNA523187 | ENA

Spatiotemporal dynamics of GEF-H1 activation controlled by microtubule- and Src-mediated pathways.

Project description:Rho family GTPases are activated with precise spatiotemporal control by guanine nucleotide exchange factors (GEFs). Guanine exchange factor H1 (GEF-H1), a RhoA activator, is thought to act as an integrator of microtubule (MT) and actin dynamics in diverse cell functions. Here we identify a GEF-H1 autoinhibitory sequence and exploit it to produce an activation biosensor to quantitatively probe the relationship between GEF-H1 conformational change, RhoA activity, and edge motion in migrating cells with micrometer- and second-scale resolution. Simultaneous imaging of MT dynamics and GEF-H1 activity revealed that autoinhibited GEF-H1 is localized to MTs, while MT depolymerization subadjacent to the cell cortex promotes GEF-H1 activation in an ~5-µm-wide peripheral band. GEF-H1 is further regulated by Src phosphorylation, activating GEF-H1 in a narrower band ~0-2 µm from the cell edge, in coordination with cell protrusions. This indicates a synergistic intersection between MT dynamics and Src signaling in RhoA activation through GEF-H1.

| S-EPMC6719461 | biostudies-literature

BNIP-2 retards breast cancer cell migration by coupling microtubule-mediated GEF-H1 and RhoA activation.

Project description:Microtubules display dynamic turnover during cell migration, leading to cell contractility and focal adhesion maturation regulated by Rho guanosine triphosphatase activity. This interplay between microtubules and actomyosin is mediated by guanine nucleotide exchange factor (GEF)-H1 released after microtubule depolymerization or microtubule disconnection from focal adhesions. However, how GEF-H1 activates Rho upon microtubule disassembly remains elusive. Here, we found that BNIP-2, a BCH domain-containing protein that binds both RhoA and GEF-H1 and traffics with kinesin-1 on microtubules, is important for GEF-H1-driven RhoA activation upon microtubule disassembly. Depletion of BNIP-2 in MDA-MB-231 breast cancer cells decreases RhoA activity and promotes cell migration. Upon nocodazole-induced microtubule disassembly, the interaction between BNIP-2 and GEF-H1 increases, while knockdown of BNIP-2 reduces RhoA activation and cell rounding via uncoupling RhoA-GEF-H1 interaction. Together, these findings revealed that BNIP-2 couples microtubules and focal adhesions via scaffolding GEF-H1 and RhoA, fine-tuning RhoA activity and cell migration.

| S-EPMC7399486 | biostudies-literature

GEF-H1 controls microtubule-dependent sensing of nucleic acids for antiviral host defenses.

Project description:Detailed understanding of the signaling intermediates that confer the sensing of intracellular viral nucleic acids for induction of type I interferons is critical for strategies to curtail viral mechanisms that impede innate immune defenses. Here we show that the activation of the microtubule-associated guanine nucleotide exchange factor GEF-H1, encoded by Arhgef2, is essential for sensing of foreign RNA by RIG-I-like receptors. Activation of GEF-H1 controls RIG-I-dependent and Mda5-dependent phosphorylation of IRF3 and induction of IFN-? expression in macrophages. Generation of Arhgef2(-/-) mice revealed a pronounced signaling defect that prevented antiviral host responses to encephalomyocarditis virus and influenza A virus. Microtubule networks sequester GEF-H1 that upon activation is released to enable antiviral signaling by intracellular nucleic acid detection pathways.

| S-EPMC4066330 | biostudies-literature

GEF-H1 controls focal adhesion signaling that regulates mesenchymal stem cell lineage commitment.

Project description:Focal adhesions (FAs) undergo maturation that culminates in size and composition changes that modulate adhesion, cytoskeleton remodeling and differentiation. Although it is well recognized that stimuli for osteogenesis of mesenchymal stem cells (MSCs) drive FA maturation, actin organization and stress fiber polarization, the extent to which FA-mediated signals regulated by the FA protein composition specifies MSC commitment remains largely unknown. Here, we demonstrate that, upon dexamethasone (osteogenic induction) treatment, guanine nucleotide exchange factor H1 (GEF-H1, also known as Rho guanine nucleotide exchange factor 2, encoded by ARHGEF2) is significantly enriched in FAs. Perturbation of GEF-H1 inhibits FA formation, anisotropic stress fiber orientation and MSC osteogenesis in an actomyosin-contractility-independent manner. To determine the role of GEF-H1 in MSC osteogenesis, we explore the GEF-H1-modulated FA proteome that reveals non-muscle myosin-II heavy chain-B (NMIIB, also known as myosin-10, encoded by MYH10) as a target of GEF-H1 in FAs. Inhibition of targeting NMIIB into FAs suppresses FA formation, stress fiber polarization, cell stiffness and osteogenic commitments in MSCs. Our data demonstrate a role for FA signaling in specifying MSC commitment.

| S-EPMC4179489 | biostudies-literature

IKK? contributes to canonical NF-?B activation downstream of Nod1-mediated peptidoglycan recognition.

Project description:BackgroundDuring pathogen infection, innate immunity is initiated via the recognition of microbial products by pattern recognition receptors and the subsequent activation of transcription factors that upregulate proinflammatory genes. By controlling the expression of cytokines, chemokines, anti-bacterial peptides and adhesion molecules, the transcription factor nuclear factor-kappa B (NF-?B) has a central function in this process. In a typical model of NF-?B activation, the recognition of pathogen associated molecules triggers the canonical NF-?B pathway that depends on the phosphorylation of Inhibitor of NF-?B (I?B) by the catalytic subunit I?B kinase ? (IKK?), its degradation and the nuclear translocation of NF-?B dimers.MethodologyHere, we performed an RNA interference (RNAi) screen on Shigella flexneri-induced NF-?B activation to identify new factors involved in the regulation of NF-?B following infection of epithelial cells by invasive bacteria. By targeting a subset of the human signaling proteome, we found that the catalytic subunit IKK? is also required for complete NF-?B activation during infection. Depletion of IKK? by RNAi strongly reduces the nuclear translocation of NF-?B p65 during S. flexneri infection as well as the expression of the proinflammatory chemokine interleukin-8. Similar to IKK?, IKK? contributes to the phosphorylation of I?B? on serines 32 and 36, and to its degradation. Experiments performed with the synthetic Nod1 ligand L-Ala-D-?-Glu-meso-diaminopimelic acid confirmed that IKK? is involved in NF-?B activation triggered downstream of Nod1-mediated peptidoglycan recognition.ConclusionsTaken together, these results demonstrate the unexpected role of IKK? in the canonical NF-?B pathway triggered by peptidoglycan recognition during bacterial infection. In addition, they suggest that IKK? may be an important drug target for the development of treatments that aim at limiting inflammation in bacterial infection.

| S-EPMC2955547 | biostudies-literature

Microtubule-Mediated NLRP3 Inflammasome Activation Is Independent of Microtubule-Associated Innate Immune Factor GEF-H1 in Murine Macrophages.

Project description:Inflammasomes are intracellular multiple protein complexes that mount innate immune responses to tissue damage and invading pathogens. Their excessive activation is crucial in the development and pathogenesis of inflammatory disorders. Microtubules have been reported to provide the platform for mediating the assembly and activation of NLRP3 inflammasome. Recently, we have identified the microtubule-associated immune molecule guanine nucleotide exchange factor-H1 (GEF-H1) that is crucial in coupling microtubule dynamics to the initiation of microtubule-mediated immune responses. However, whether GEF-H1 also controls the activation of other immune receptors that require microtubules is still undefined. Here we employed GEF-H1-deficient mouse bone marrow-derived macrophages (BMDMs) to interrogate the impact of GEF-H1 on the activation of NLRP3 inflammasome. NLRP3 but not NLRC4 or AIM2 inflammasome-mediated IL-1? production was dependent on dynamic microtubule network in wild-type (WT) BMDMs. However, GEF-H1 deficiency did not affect NLRP3-driven IL-1? maturation and secretion in macrophages. Moreover, ?-tubulin acetylation and mitochondria aggregations were comparable between WT and GEF-H1-deficient BMDMs in response to NLRP3 inducers. Further, GEF-H1 was not required for NLRP3-mediated immune defense against Salmonella typhimurium infection. Collectively, these findings suggest that the microtubule-associated immune modulator GEF-H1 is dispensable for microtubule-mediated NLRP3 activation and host defense in mouse macrophages.

| S-EPMC7072875 | biostudies-literature

Autophagy suppresses cell migration by degrading GEF-H1, a RhoA GEF.

Project description:Cell migration is a process crucial for a variety of biological events, such as morphogenesis and wound healing. Several reports have described the possible regulation of cell migration by autophagy; however, this remains controversial. We here demonstrate that mouse embryonic fibroblasts (MEFs) lacking autophagy protein 5 (Atg5), an essential molecule of autophagy, moved faster than wild-type (WT) MEFs. Similar results were obtained for MEFs lacking Atg7 and unc-51-like kinase 1 (Ulk1), which are molecules required for autophagy. This phenotype was also observed in Atg7-deficient macrophages. WT MEFs moved by mesenchymal-type migration, whereas Atg5 knockout (KO) MEFs moved by amoeba-like migration. This difference was thought to be mediated by the level of RhoA activity, because Atg5 KO MEFs had higher RhoA activity, and treatment with a RhoA inhibitor altered Atg5 KO MEF migration from the amoeba type to the mesenchymal type. Autophagic regulation of RhoA activity was dependent on GEF-H1, a member of the RhoA family of guanine nucleotide exchange factors. In WT MEFs, GEF-H1 directly bound to p62 and was degraded by autophagy, resulting in low RhoA activity. In contrast, the loss of autophagy increased GEF-H1 levels and thereby activated RhoA, which caused cells to move by amoeba-like migration. This amoeba-like migration was cancelled by the silencing of GEF-H1. These results indicate that autophagy plays a role in the regulation of migration by degrading GEF-H1.

| S-EPMC5085165 | biostudies-literature

IKK? is an IRF5 kinase that instigates inflammation.

Project description:The transcription factor interferon regulatory factor 5 (IRF5) is essential for the induction of inflammatory cytokines, but the mechanism by which IRF5 is activated is not well understood. Here we present evidence that the kinase IKK? phosphorylates and activates IRF5 in response to stimulation in several inflammatory pathways, including those emanated from Toll-like receptors and retinoic acid-inducible gene I-like receptors. IKK? phosphorylates mouse IRF5 at specific residues, including serine 445 (S446 in human IRF5 isoform 1), as evidenced by mass spectrometry analysis and detection with a phosphospecific antibody. Recombinant IKK? phosphorylated IRF5 at Ser-445 in vitro, and a point mutation of this serine abolished IRF5 activation and cytokine production. Depletion or pharmacologic inhibition of IKK? prevented IRF5 phosphorylation. These results indicate that IKK? is an IRF5 kinase that instigates inflammation.

| S-EPMC4267374 | biostudies-other

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data