Cellular pyrimdine imbalance triggers mitochondrial DNA-dependent innate immunity [Scr_vs_Yme1l-si_RNA-seq]
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE161734 | GEO | 2021/02/26
REPOSITORIES: GEO
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Project description:Cytosolic mitochondrial DNA (mtDNA) elicits a type I interferon response, but signals triggering the release of mtDNA from mitochondria remain enigmatic. Here, we show that mtDNA-dependent immune signalling via the cyclic GMP–AMP syn- thase‒stimulator of interferon genes‒TANK-binding kinase 1 (cGAS–STING–TBK1) pathway is under metabolic control and is induced by cellular pyrimidine deficiency. The mitochondrial protease YME1L preserves pyrimidine pools by supporting de novo nucleotide synthesis and by proteolysis of the pyrimidine nucleotide carrier SLC25A33. Deficiency of YME1L causes inflamma- tion in mouse retinas and in cultured cells. It drives the release of mtDNA and a cGAS–STING–TBK1-dependent inflammatory response, which requires SLC25A33 and is suppressed upon replenishment of cellular pyrimidine pools. Overexpression of SLC25A33 is sufficient to induce immune signalling by mtDNA. Similarly, depletion of cytosolic nucleotides upon inhibition of de novo pyrimidine synthesis triggers mtDNA-dependent immune responses in wild-type cells. Our results thus identify mtDNA release and innate immune signalling as a metabolic response to cellular pyrimidine deficiencies.
2021-02-26 | GSE161735 | GEO
Project description:Cytosolic mitochondrial DNA (mtDNA) elicits a type I interferon response, but signals triggering the release of mtDNA from mitochondria remain enigmatic. Here, we show that mtDNA-dependent immune signalling via the cyclic GMP–AMP syn- thase‒stimulator of interferon genes‒TANK-binding kinase 1 (cGAS–STING–TBK1) pathway is under metabolic control and is induced by cellular pyrimidine deficiency. The mitochondrial protease YME1L preserves pyrimidine pools by supporting de novo nucleotide synthesis and by proteolysis of the pyrimidine nucleotide carrier SLC25A33. Deficiency of YME1L causes inflamma- tion in mouse retinas and in cultured cells. It drives the release of mtDNA and a cGAS–STING–TBK1-dependent inflammatory response, which requires SLC25A33 and is suppressed upon replenishment of cellular pyrimidine pools. Overexpression of SLC25A33 is sufficient to induce immune signalling by mtDNA. Similarly, depletion of cytosolic nucleotides upon inhibition of de novo pyrimidine synthesis triggers mtDNA-dependent immune responses in wild-type cells. Our results thus identify mtDNA release and innate immune signalling as a metabolic response to cellular pyrimidine deficiencies.
2021-02-26 | GSE161733 | GEO
Project description:Cytosolic mitochondrial DNA (mtDNA) elicits a type I interferon response, but signals triggering the release of mtDNA from mitochondria remain enigmatic. Here, we show that mtDNA-dependent immune signalling via the cyclic GMP–AMP syn- thase‒stimulator of interferon genes‒TANK-binding kinase 1 (cGAS–STING–TBK1) pathway is under metabolic control and is induced by cellular pyrimidine deficiency. The mitochondrial protease YME1L preserves pyrimidine pools by supporting de novo nucleotide synthesis and by proteolysis of the pyrimidine nucleotide carrier SLC25A33. Deficiency of YME1L causes inflamma- tion in mouse retinas and in cultured cells. It drives the release of mtDNA and a cGAS–STING–TBK1-dependent inflammatory response, which requires SLC25A33 and is suppressed upon replenishment of cellular pyrimidine pools. Overexpression of SLC25A33 is sufficient to induce immune signalling by mtDNA. Similarly, depletion of cytosolic nucleotides upon inhibition of de novo pyrimidine synthesis triggers mtDNA-dependent immune responses in wild-type cells. Our results thus identify mtDNA release and innate immune signalling as a metabolic response to cellular pyrimidine deficiencies.
2021-02-26 | GSE161732 | GEO
Project description:Cytosolic mitochondrial DNA (mtDNA) elicits a type I interferon response, but signals triggering the release of mtDNA from mitochondria remain enigmatic. We found that mtDNA-dependent immune signalling via the cGAS-STING pathway is under metabolic control and induced by cellular nucleotide deficiency. The mitochondrial protease YME1L preserves nucleotide pools by supporting de novo nucleotide synthesis and by proteolysis of the pyrimidine nucleotide carrier SLC25A33, limiting mitochondrial nucleotide transport and accumulation of mtDNA. Deficiency of YME1L or of the mitochondrial transcription factor A (TFAM) drives an mtDNA-dependent inflammatory response, which depends on SLC25A33 and is suppressed upon replenishment of cellular nucleotide pools. Depletion of cytosolic nucleotides upon starvation or downregulation of de novo nucleotide synthesis triggers mtDNA-dependent immune responses. Our results thus identify mtDNA release and innate immune signalling as a metabolic response, offering new therapeutic opportunities in disease.
2021-04-27 | PXD019849 | Pride
Project description:Cytosolic mitochondrial DNA (mtDNA) elicits a type I interferon response, but signals triggering the release of mtDNA from mitochondria remained enigmatic. We found that mtDNA-dependent immune signaling via the cGAS-STING pathway is under metabolic control and induced by cellular nucleotide deficiency. The mitochondrial protease YME1L preserves nucleotide pools by supporting de novo nucleotide synthesis and by proteolysis of the pyrimidine nucleotide carrier SLC25A33, limiting mitochondrial nucleotide import and accumulation of mtDNA. Deficiency of YME1L or the mitochondrial transcription factor A (TFAM) drives an mtDNA-dependent inflammatory response, which depends on SLC25A33 and is suppressed upon replenishment of cellular nucleotide pools. Metabolic insults that deplete cytosolic nucleotides trigger mtDNA-dependent immune responses. Our results thus identify mtDNA release and innate immune signaling as a metabolic response, offering new therapeutic opportunities in disease.
2021-04-27 | PXD018097 | Pride
Project description:The cyclic GMP-AMP synthase (cGAS) recognizes Y-form cDNA of HIV-1 and initiate the antiviral immune response through cGAS–STING–TBK1–IRF3–type I IFN (IFN-I) signaling cascade. HIV-1 uses several strategies to interfere with the host immune molecules and mediate immune evasion. However, the potential role of HIV-1 proteins in cGAS–STING signaling remains unclear. Here we report that the HIV-1 protein p6 suppresses HIV-1-stimulated expression of IFN-I and promotes the immune evasion. Mechanistically, p6 bound with STING and inhibited the activation of STING and the interaction between STING and TBK1. Moreover, the glutamylation of p6 at Glu6 residue inhibited the interaction between STING and TRIM32 or AMFR, which subsequently suppressed the K27- and K63-linked polyubiquitination of STING at Lys337, therefore inhibited STING activation and type I IFN production, while the mutation of Glu6 residue lost the inhibitory effect. However, CoCl2, an agonist for cytosolic carboxypeptidases (CCPs), counteracted the glutamylation of Glu6 residue of p6 and promoted IFN-I production to block the immune evasion of HIV-1. These findings not only reveal a previously unknown mechanism through which an HIV-1 protein mediate immune evasion, but also provide a new therapeutic drug candidate to treat HIV-1 infection.
2021-11-25 | GSE189384 | GEO
Project description:The goal of this analysis was to utilize microarray profiling to identify basal alterations in gene expression in response to TFAM depletion and mtDNA stress. Mitochondrial DNA (mtDNA) is normally present at thousands of copies per cell and is packaged into several hundred higher-order structures termed nucleoids. The abundant mtDNA-binding protein, TFAM (transcription factor A,mitochondrial), regulates nucleoid architecture, abundance and segregation. Complete mtDNA depletion profoundly impairs oxidative phosphorylation, triggering calcium-dependent stress signalling and adaptive metabolic responses. However, the cellular responses to mtDNA instability, a physiologically relevant stress observed in many human diseases and ageing, remain poorly defined. Here we show that moderate mtDNA stress elicited by TFAM deficiency engages cytosolic antiviral signalling to enhance the expression of a subset of interferon-stimulated genes. Mechanistically, we find that aberrant mtDNA packaging promotes escape of mtDNA into the cytosol, where it engages the DNA sensor cGAS (also known as MB21D1) and promotes STING (also known as TMEM173)–IRF3-dependent signalling to elevate interferon-stimulated gene expression, potentiate type I interferon responses and confer broad viral resistance. Furthermore, we demonstrate that herpesviruses induce mtDNA stress, which enhances antiviral signalling and type I interferon responses during infection. Our results further demonstrate that mitochondria are central participants in innate immunity, identify mtDNA stress as a cell-intrinsic trigger of antiviral signaling and suggest that cellular monitoring of mtDNA homeostasis cooperates with canonical virus sensing mechanisms to fully engage antiviral innate immunity. Murine embryonic fibroblasts were isolated from wild-type or Tfam+/- E13.5 littermate embryos. RNA from passage-matched wild-type and Tfam+/- MEF lines was extracted in duplicate and hybridized onto Affymetrix microarrays. Four arrays were performed in total with two technical replicates per genotype.
2015-01-26 | E-GEOD-63767 | biostudies-arrayexpress
Project description:RIG-I like helicases (RLHs) and cGAS are crucial cytosolic sensors of viral RNA and DNA, respectively, and induce type I IFNs via TBK1/IKKε. hnRNPM was described to possess antimicrobial activities. Here, we show that hnRNPM promotes TBK1/IRF3 phosphorylation and type I IFN induction downstream of cGAS and RIG-I in THP-1 cells and primary human fibroblasts. Interactome analysis revealed that hnRNPM forms a multiprotein complex with ELAVL1, SON, TBK1, IKKε, IKKβ, and NF-κB p65. The purified hnRNPM complex enhanced TBK1 phosphorylation. Vice versa, TBK1 directly phosphorylated ELAVL1. hnRNPM, ELAVL1, and TBK1 predominantly interacted in the cytosol. Of note, patients with mutations in SON suffer from recurrent infections, further underlining its biologic significance. To our knowledge, hnRNPM, ELAVL1, and SON represent the first non-redundant signaling components merging the cGAS-STING and RIG-I–MAVS pathways. Therefore, our findings may have implications for host defense and auto-inflammatory diseases.
2023-09-16 | GSE184273 | GEO
Project description:Low-grade inflammation is a hallmark of old age and a central driver of ageing-associated impairment and disease. Multiple factors can contribute to ageing-associated inflammation, however the molecular pathways transducing aberrant inflammatory signalling and their impact in natural ageing remain poorly understood. Here we show that the cGAS-STING signalling pathway, mediating immune sensing of DNA, is a critical driver of chronic inflammation and functional decline during ageing. Blockade of STING suppresses the inflammatory phenotypes of senescent human cells and tissues, attenuates ageing-related inflammation in multiple peripheral organs and the brain in mice, and leads to an improvement in tissue function. Focusing on the ageing brain, we reveal that activation of STING triggers reactive microglia transcriptional states, neurodegeneration and cognitive decline. Cytosolic DNA released from perturbed mitochondria elicits cGAS activity in old microglia defining a mechanism by which cGAS-STING signalling is engaged in the ageing brain. Single-nuclei RNA-sequencing (snRNA-seq) of microglia and hippocampi of a newly developed cGAS gain-of-function mouse model demonstrates that engagement of cGAS in microglia is sufficient to direct ageing-associated transcriptional microglia states leading to bystander cell inflammation, neurotoxicity and impaired memory capacity. Our findings establish the cGAS-STING pathway as a critical driver of ageing-related inflammation in peripheral organs and the brain, and reveal blockade of cGAS-STING signalling as a potential strategy to halt (neuro)degenerative processes during old age.
2023-08-20 | GSE234420 | GEO
Project description:Low-grade inflammation is a hallmark of old age and a central driver of ageing-associated impairment and disease. Multiple factors can contribute to ageing-associated inflammation, however the molecular pathways transducing aberrant inflammatory signalling and their impact in natural ageing remain poorly understood. Here we show that the cGAS-STING signalling pathway, mediating immune sensing of DNA, is a critical driver of chronic inflammation and functional decline during ageing. Blockade of STING suppresses the inflammatory phenotypes of senescent human cells and tissues, attenuates ageing-related inflammation in multiple peripheral organs and the brain in mice, and leads to an improvement in tissue function. Focusing on the ageing brain, we reveal that activation of STING triggers reactive microglia transcriptional states, neurodegeneration and cognitive decline. Cytosolic DNA released from perturbed mitochondria elicits cGAS activity in old microglia defining a mechanism by which cGAS-STING signalling is engaged in the ageing brain. Single-nuclei RNA-sequencing (snRNA-seq) of microglia and hippocampi of a newly developed cGAS gain-of-function mouse model demonstrates that engagement of cGAS in microglia is sufficient to direct ageing-associated transcriptional microglia states leading to bystander cell inflammation, neurotoxicity and impaired memory capacity. Our findings establish the cGAS-STING pathway as a critical driver of ageing-related inflammation in peripheral organs and the brain, and reveal blockade of cGAS-STING signalling as a potential strategy to halt (neuro)degenerative processes during old age.
2023-08-20 | GSE234419 | GEO