Similar Datasets
Project description:Loss of SAMHD1 causes chronic activaiton of the MDA5/MAVS dsRNA sensing pathway, only when cGAS/STING signaling is intact. Peritoneal macrophages from mutant and control mice were isolated by FACS. Total RNA was subjected to next generation mRNA sequencing.
2022-10-10 | GSE214712 | GEO
Project description:This SuperSeries is composed of the SubSeries listed below.
2022-08-18 | GSE211211 | GEO
Project description:Loss of SAMHD1 causes chronic activaiton of the MDA5/MAVS dsRNA sensing pathway, only when cGAS/STING signaling is intact. Peritoneal macrophages from mutant and control mice were isolated by FACS. Total RNA was subjected to next generation mRNA sequencing.
2022-10-10 | GSE214711 | GEO
Project description:Loss of SAMHD1 causes chronic activaiton of the MDA5/MAVS dsRNA sensing pathway, only when cGAS/STING signaling is intact.
2022-08-18 | GSE211209 | GEO
Project description:Loss of SAMHD1 causes chronic activaiton of the MDA5/MAVS dsRNA sensing pathway, only when cGAS/STING signaling is intact.
2022-08-18 | GSE211208 | GEO
Project description:We show that Manganese (II) is a potent type I-IFN inducing agonist, stimulating cells into an anti-viral state in the absence of infection. Mechanically, Mn2+ treatment led to a profound cGAS-STING-dependent innate immune activation, conferring cells or mice viral resistance.
2018-10-09 | GSE77216 | GEO
Project description:SAMHD1 is a restriction factor for HIV-1 infection. SAMHD1 mutations cause the autoinflammatory Aicardi-Goutières syndrome that is characterized by chronic type I interferon (IFN) secretion. We show that the spontaneous IFN response in SAMHD1-deficient cells and mice requires the cGAS/STING cytosolic DNA-sensing pathway. We provide genetic evidence that cell-autonomous control of lentivirus infection in myeloid cells by SAMHD1 limits virus-induced production of IFNs and the induction of co-stimulatory markers. This program of myeloid cell activation required reverse transcription, cGAS and STING, and signaling through the IFN receptor. Furthermore, SAMHD1 reduced the induction of virus-specific cytotoxic T cells in vivo. Therefore, virus restriction by SAMHD1 limits the magnitude of IFN and T cell responses. This demonstrates a competition between cell-autonomous virus control and subsequent innate and adaptive immune responses, a concept with important implications for the treatment of infection.
| S-EPMC4978700 | biostudies-literature
Project description:Tumors with defective mismatch repair (dMMR) are responsive to immunotherapy because of dMMR-induced neoantigens and activation of the cGAS-STING pathway. While neoantigens result from the hypermutable nature of dMMR, it is unknown how dMMR activates the cGAS-STING pathway. We show here that loss of the MutLα subunit MLH1, whose defect is responsible for ~50% of dMMR cancers, results in loss of MutLα-specific regulation of exonuclease 1 (Exo1) during DNA repair. This leads to unrestrained DNA excision by Exo1, which causes increased single-strand DNA formation, RPA exhaustion, DNA breaks, and aberrant DNA repair intermediates. Ultimately, this generates chromosomal abnormalities and the release of nuclear DNA into the cytoplasm, activating the cGAS-STING pathway. In this study, we discovered a hitherto unknown MMR mechanism that modulates genome stability and has implications for cancer therapy.
| S-EPMC8666006 | biostudies-literature
Project description:Detection of cytoplasmic DNA represents one of the most fundamental mechanisms of the innate immune system to sense the presence of microbial pathogens. Moreover, erroneous detection of endogenous DNA by the same sensing mechanisms has an important pathophysiological role in certain sterile inflammatory conditions. The endoplasmic-reticulum-resident protein STING is critically required for the initiation of type I interferon signalling upon detection of cytosolic DNA of both exogenous and endogenous origin. Next to its pivotal role in DNA sensing, STING also serves as a direct receptor for the detection of cyclic dinucleotides, which function as second messenger molecules in bacteria. DNA recognition, however, is triggered in an indirect fashion that depends on a recently characterized cytoplasmic nucleotidyl transferase, termed cGAMP synthase (cGAS), which upon interaction with DNA synthesizes a dinucleotide molecule that in turn binds to and activates STING. We here show in vivo and in vitro that the cGAS-catalysed reaction product is distinct from previously characterized cyclic dinucleotides. Using a combinatorial approach based on mass spectrometry, enzymatic digestion, NMR analysis and chemical synthesis we demonstrate that cGAS produces a cyclic GMP-AMP dinucleotide, which comprises a 2'-5' and a 3'-5' phosphodiester linkage >Gp(2'-5')Ap(3'-5')>. We found that the presence of this 2'-5' linkage was required to exert potent activation of human STING. Moreover, we show that cGAS first catalyses the synthesis of a linear 2'-5'-linked dinucleotide, which is then subject to cGAS-dependent cyclization in a second step through a 3'-5' phosphodiester linkage. This 13-membered ring structure defines a novel class of second messenger molecules, extending the family of 2'-5'-linked antiviral biomolecules.
| S-EPMC4143541 | biostudies-literature
Project description:Brain inflammation generally accompanies and accelerates neurodegeneration. Here we report a microglial mechanism in which polyglutamine binding protein 1 (PQBP1) senses extrinsic tau 3R/4R proteins by direct interaction and triggers an innate immune response by activating a cyclic GMP-AMP synthase (cGAS)-Stimulator of interferon genes (STING) pathway. Tamoxifen-inducible and microglia-specific depletion of PQBP1 in primary culture in vitro and mouse brain in vivo shows that PQBP1 is essential for sensing-tau to induce nuclear translocation of nuclear factor κB (NFκB), NFκB-dependent transcription of inflammation genes, brain inflammation in vivo, and eventually mouse cognitive impairment. Collectively, PQBP1 is an intracellular receptor in the cGAS-STING pathway not only for cDNA of human immunodeficiency virus (HIV) but also for the transmissible neurodegenerative disease protein tau. This study characterises a mechanism of brain inflammation that is common to virus infection and neurodegenerative disorders. Brain inflammation generally accelerates neurodegeneration but the mechanisms of this are not fully characterised. Here the authors show that PQBP1 in microglia is important for sensing extrinsic Tau 3 R/4 R proteins and triggers an innate immune response through cGAS and STING resulting in cognitive impairment.
| S-EPMC8592984 | biostudies-literature