An inherited mtDNA mutation remodels inflammatory cytokine responses in macrophages and in vivo
Ontology highlight
ABSTRACT:
INSTRUMENT(S):
ORGANISM(S): Mus Musculus (mouse)
TISSUE(S): Macrophage
SUBMITTER: 
Alex von Kriegsheim
LAB HEAD: Dylan Ryan
PROVIDER: PXD060284 | Pride | 2025-09-17
REPOSITORIES: Pride
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| 20230830WTand5019.zip | Other | |||
| 5019A_PBS_F_K.raw | Raw | |||
| 5019A_PBS_F_L.raw | Raw | |||
| 5019A_PBS_M_K.raw | Raw | |||
| 5019A_PBS_M_L.raw | Raw |
Items per page: 5 1 - 5 of 82 |
Similar Datasets
Project description:The controlled release of mitochondrial content has emerged as a key step in mitochondrial signaling. Particularly the release of mitochondrial DNA (mtDNA) into the cytosol has been shown to activate interferon beta (IFN-β) gene expression to execute the innate immune response. In this report, we show that human adenovirus type 5 (HAdV-C5) induces the release of mtDNA in infected cells. The release of mtDNA is mediated by the viral internal minor capsid protein pVI, which localizes into mitochondria and undergoes mitochondria-specific proteolytic processing. The membrane lytic activity of the pVI and the presence of the mitochondrial membrane proteins Bak and Bax are needed for the mtDNA release. Surprisingly, the pVI-mediate mtDNA release did not increase but blocked IFN-β gene expression. This inhibition was due to the concurrent leakage of the mitochondrial chaperon protein HSP60, which by inhibiting phosphorylation of the interferon regulatory factor 3 (IRF3), blocked IFN-β gene expression. Collectively, our study suggests that the complex release of mtDNA and mitochondrial proteins modulate the IFN-β signaling cascade during pathogenic HAdV-C5 infection.
2024-05-27 | PXD043440 | Pride
Project description:The mitochondrial and nuclear genomes contribute to mitochondrial function, and when mitochondrial function is compromised, mitochondrial retrograde signaling alters nuclear gene expression. We performed gene expression profiling of engineered cells that had mitochondria containing a disease-associated mutation that causes mitochondrial dysfunction. By generating networks of transcription factors that targeted these genes, the authors revealed putative mitochondrial retrograde signaling pathways. One such pathway involved retinoic acid receptor alpha (RXRA), the mRNA for which was reduced in the mutant cells. Network analysis and experiments in cells suggested that mitochondrial dysfunction caused by the mutation initiated a positive feedback loop that aggravated mitochondrial dysfunction: Reduced RXRA abundance further compromised expression of genes encoding products involved in mitochondrial function and translation. This gene-transcription factor mapping-network approach may reveal targets for therapeutic intervention of diseases associated with mitochondrial dysfunction. To investigate retrograde signaling pathways induced by the mitochondrial dysfunction caused by the mt3243 mutation, we generated the three types of cybrid cells using a mitochondria-mediated transformation method. Cells lacking mtDNA (rho0) were fused with mtDNAs with the mt3243 mutation isolated from platelets of a diabetic patient with sensorineural hearing loss. We then isolated three types of cybrid cells: W cells had wild-type mtDNA (3243A homoplasmy), H cells had both the mutant and wild-type mtDNA (3243A/G heteroplasmy) with 70% of the mtDNA containing 3243G, and M cells with only mutant mtDNA (3243G homoplasmy). Gene expression profiles of cybrid cells were generated using Illumina HumanHT-12-v3-BeadChip (Illumina, San Diego, CA), which includes 49,896 probes corresponding to 25,202 annotated genes. According to the Illumina protocols, three biological triplicates of each type of cybrid cells were analyzed. Total RNA (500ng) was isolated from cybrid cells using RNeasy Mini Kit (Qiagen, GmbH, Germany). RNA integrity number (RIN) was in the range of RIN = 9.2 and 10 when measured with an Agilent 2100 Bioanalyzer. RNA was reversely transcribed and amplified using IlluminaTotalPrep RNA amplification kit (Ambion, Austin, TX). In vitro transcription was then carried out to prepare cRNA. The cRNAs were hybridized to the array and then labeled with Cy3-streptavidin (Amersham Bioscience, Little Chalfont, UK). The fluorescent signal on the array was measured with a BeadStation 500 System (Illumina, San Diego, CA).
2013-02-12 | E-GEOD-27545 | biostudies-arrayexpress
Project description:It has been reported that human mesenchymal stem cells (MSCs) can transfer mitochondria to the cells with severely compromised mitochondrial function. We tested whether MSCs transfer mitochondria to the cells under several different conditions of mitochondrial dysfunction, including human pathogenic mitochondrial DNA (mtDNA) mutations. Using biochemical selection methods, we found that exponentially growing cells in restrictive media (uridine and bromodeoxyuridine [BrdU]+) after coculture of MSCs (uridine-independent and BrdU-sensitive) and 143B-derived cells with severe mitochondrial dysfunction induced by either long-term ethidium bromide treatment or short-term rhodamine 6G (R6G) treatment (uridine-dependent but BrdU-resistant). The exponentially growing cells had nuclear DNA fingerprint patterns identical to 143B, and a sequence of mtDNA identical to the MSCs. Since R6G causes rapid and irreversible damage to mitochondria without the removal of mtDNA, the mitochondrial function appears to be restored through a direct transfer of mitochondria rather than mtDNA alone. Conditioned media, which were prepared by treating mtDNA-less 143B 0 cells under uridine-free condition, induced increased chemotaxis in MSC, which was also supported by transcriptome analysis. A chemotaxis inhibitory agent blocked mitochondrial transfer phenomenon in the above condition. However, we could not find any evidence of mitochondrial transfer to the cells harboring human pathogenic mtDNA mutations (A3243G mutation or 4,977 bp deletion). Thus, the mitochondrial transfer is limited to the condition of a near total absence of mitochondrial function. Elucidation of the mechanism of mitochondrial transfer will help us create a potential “cell therapy-based mitochondrial restoration or mitochondrial gene therapy” for human diseases caused by mitochondrial dysfunction. time series
2011-11-22 | E-GEOD-33831 | biostudies-arrayexpress
Project description:Mitochondrial damage causes mtDNA release to activate type I interferon (IFN-I) response via the cGAS-STING pathway. mtDNA-induced inflammation promotes autoimmune and aging-related degenerative disorders. However, the global picture of inflammation-inducing mitochondrial damages remains obscure. Here we performed a mitochondria-targeted CRISPR-knockout screen for regulators of the IFN-I response. Strikingly, our screen revealed dozens of hits enriched with key regulators of cristae architecture, including phospholipid cardiolipin and protein complexes such as OPA1, MICOS, SAM, MIB, PHB, and the F1Fo-ATP synthase. Disrupting these cristae organizers consistently induced mtDNA release and STING-dependent IFN-I response. Furthermore, robust STING-dependent IFN-I response was induced in vivo by knocking out MTX2, a subunit of the SAM complex whose null-mutations cause progeria in human. Taken together, beyond revealing the central role of cristae architecture to prevent mtDNA release and inflammation, our results mechanistically link mitochondrial cristae disorganization and inflammation, two emerging hallmarks of aging and aging-related degenerative diseases.
2022-10-28 | GSE216499 | GEO
Project description:BACKGROUND: Mitochondrial dysfunction is a key factor in the development of atherogenesis. Methyltransferase-like protein 4 (METTL4) mediates N6-deoxyadenosine (6mA) methylation of mammalian mitochondrial DNA (mtDNA). However, the role of METTL4-mediated mitoepigenetic regulation in atherosclerosis is still unknown. This study aims to investigate the potential involvement of METTL4 in atherosclerosis, explore the underlying mechanism, and develop targeted strategies for treating atherosclerosis. METHODS: Expression levels of mtDNA 6mA and METTL4 were determined in atherosclerotic lesions. We explored the mechanism of METTL4 involvement in atherosclerosis using Mettl4Mac-KO-Apoe-/- and Mettl4MUT-Apoe-/- mice and cell models, as well as bone marrow transplantation. Natural compound libraries were screened to identify potent METTL4 antagonists. In addition, bioinspired proteolysis-targeting (PROTAC) technology targeting macrophages within plaques was used to increase the efficacy of the METTL4 antagonist. RESULTS: The expression levels of mtDNA 6mA and METTL4 were significantly increased in plaque macrophages. Mettl4Mac-KO-Apoe-/- mice displayed suppressed mtDNA 6mA levels and atherosclerotic progression, which were reversed by METTL4 restoration via bone marrow transplantation (n = 6). Mechanistically, elevated METTL4 expression reduces MT-ATP6 expression by suppressing its transcription, thereby impairing the activity of mitochondrial respiration chain complex V. This disruption leads to the accumulation of excess protons in the mitochondrial intermembrane space, causing mitochondrial dysfunction. Consequently, mtDNA is released into the cytoplasm, ultimately triggering inflammasome activation. All results were reversed by the mutation in the METTL4 methyltransferase active site. Mettl4MUT-Apoe-/- mice showed suppressed mtDNA 6mA levels and atherosclerotic progression, and repaired mitochondrial function of macrophage, which were reversed by METTL4 restoration via bone marrow transplantation (n = 6). Pemetrexed (PEM) was identified as the first METTL4 antagonist to effectively alleviate atherosclerotic progression. Furthermore, we generated a proteolysis-targeting chimera drug based on PEM (PROTAC-PEM) that specifically targeting METTL4 in macrophages within plaques, showing a promising therapeutic effect on atherosclerosis. CONCLUSIONS: This study revealed a novel mechanism by which mtDNA 6mA orchestrated mitochondrial function-related gene expression in macrophages, thereby promoting atherosclerosis. Through various experimental techniques, such as gene manipulation, pharmacological inhibition and PROTAC, this study demonstrated that mtDNA 6mA and its specific enzyme METTL4 hold potential as therapeutic targets for atherosclerosis.
2024-11-02 | GSE280434 | GEO
Project description:Study of macrophages in a mouse model of mitochondrial disease caused by mtDNA heteroplasmy (m.5019A>G)
| MSV000099126 | MassIVE
Project description:Damage to the mitochondrial genome (mtDNA) severely affects the cell and causes disease. Mutations to mtDNA also accumulate throughout the lifespan of many organisms and may be a proximal cause of aging. There is no effective treatment for ailments caused by mtDNA mutation. Since mitochondrial function and biogenesis are controlled by the nutrient environment of the cell, it is possible that perturbation of conserved, nutrient-sensing pathways may successfully treat mitochondrial disease. Experiments using the tractable eukaryote Saccharomyces cerevisiae allow us to investigate the connection between nutrient-sensing and mitochondrial function. We have focused our current studies on the protein kinase A (PKA) pathway, which controls S. cerevisiae behavior according to glucose availability. We found that reduced PKA signaling can lead, in a background-dependent manner, to improved fitness after mtDNA loss. Specifically, over-expression of the cyclic AMP phosphodiesterase Pde2p, removal of PKA isoform Tpk3p, or ablation of other proteins promoting PKA activity leads to improved proliferation of cells deleted of the mitochondrial genome. Over-expression of Pde2p also suppresses the inviability of several mutants that normally cannot survive mtDNA loss. Moreover, Pde2p over-expression diminishes the nuclear transcriptional response to mtDNA damage, further supporting the idea that glucose sensation is harmful for cells lacking the mitochondrial genome. These findings are heavily dependent upon yeast genetic background. Interestingly, robust import of mitochondrial polytopic membrane proteins may be required in order for cells with no mtDNA to receive the full benefits of PKA reduction. Our findings support the idea that perturbation of nutrient-sensing pathways, and specifically the sensation of glucose, may benefit cells with dysfunctional mitochondria. Four experimental conditions were used: BY4743 (WT) cells containing empty pRS426 vector and containing mtDNA because EtBr was not used, BY4743 (WT) cells containing empty pRS426 vector and lacking mtDNA after 24 hours of treatment with 25 µg/ml ethidium bromide, BY4743 (WT) cells overexpressing TIP41 from plasmid pRS426 and lacking mtDNA after 24 hours of treatment with 25 µg/ml ethidium bromide, and BY4743 (WT) cells overexpressing PDE2 from plasmid pRS426 and lacking mtDNA after 24 hours of treatment with 25 µg/ml ethidium bromide. Two replicates were performed for each sample type.
2015-08-07 | E-GEOD-71252 | biostudies-arrayexpress
Project description:Exercise is a fundamental component of human health that is associated with greater life expectancy and reduced risk of chronic diseases. While the beneficial effects of endurance exercise on human health are well established, the molecular mechanisms responsible for these observations remain unclear. Endurance exercise reduces the accumulation of mitochondrial DNA (mtDNA) mutations, alleviates multisystem pathology, and increases the lifespan of the mtDNA mutator mouse model of aging, in which the proof-reading capacity of mitochondrial polymerase gamma (POLG1) is deficient. Clearly, exercise recruited a POLG1-independent mtDNA repair pathway to induce these adaptations, a novel finding as POLG1 is canonically considered to be the sole mtDNA repair enzyme. Here we investigate the identity of this pathway, and show that endurance exercise prevents mitochondrial oxidative damage, attenuates telomere erosion, and mitigates cellular senescence and apoptosis in mtDNA mutator mice. Unexpectedly, we observe translocation of tumour suppressor protein p53 to mitochondria in response to endurance exercise that facilitates mtDNA mutation repair. Indeed, endurance exercise failed to prevent mtDNA mutations, induce mitochondrial biogenesis, preserve mitochondrial morphology, reverse sarcopenia, and mitigate premature mortality in mtDNA mutator mice with muscle-specific deletion of p53. Our data establish an exciting new role for p53 in exercise-mediated maintenance of the mtDNA genome, and presents mitochondrially-targeted p53 as a novel therapeutic modality for aging-associated diseases of mitochondrial etiology. Microarray analysis of gene expression from skeletal muscle (quadriceps femoris) from Mus musculus. N=23 samples per treatment were analysed for whole transcriptiome gene expression profile using NimbleGen Arrays. The treatment groups included wild-type C57Bl/6J mice as the control group, then two treatment groups which both contained homozygous knock-in mtDNA mutator mice (PolG; PolgAD257A/D257A). Once group of these heterozygous knock out mice received regular endurance exercise sessions while the other group remained sedentraty for 6 months. The control group specimens were wild-type litter mates to the transgenic knockout mice.
2015-12-11 | E-GEOD-75869 | biostudies-arrayexpress
Project description:Damage associated molecular patterns (DAMP) trigger inflammation and provide co-stimulatory signals to adaptive immune cells, but whether and how recurring innate stimuli circumvent self-tolerance and initiate maladaptive autoimmunity is unknown. We explored if oxidized mitochondrial DNA (Ox-mtDNA), a DAMP released by stressed macrophages, found in higher amounts in diverse metabolic and autoimmune disorders, including systemic lupus erythematosus (SLE), initiates antibody-mediated autoimmunity. Indeed, Ox-mtDNA release induced by repetitive alum challenges elicited germinal center reactions, autoantibody production and nephropathology. These responses were recapitulated by in-vitro generated Ox-mtDNA, while non-oxidized mtDNA was non-pathogenic. Both mtDNA forms, but not nuclear DNA, were internalized by plasmacytoid dendritic cells (pDC), activated NF-kB via TLR9 and induced interferon (IFN)-I. Yet only Ox-mtDNA triggered NLRP3- and gasdermin D-dependent IL-1β secretion, eliciting autocrine production of IL-21 that together with IL-1β, but independently of IFN-I, enabled pDC to convert naïve CD4+ T cells into follicular helper cells. Highlighting Ox-mtDNA as a uniquely immunogenic DAMP that is specifically sensed by pDC and IL-1β as an orchestrator of autoantibody production, these findings explain how chronic inflammation culminates in autoimmunity and unravel new therapeutic targets applicable to SLE, the autoimmune/inflammatory syndrome induced by adjuvants (ASIA) and related diseases.
2025-04-10 | GSE264620 | GEO
Project description:Damage associated molecular patterns (DAMP) trigger inflammation and provide co-stimulatory signals to adaptive immune cells, but whether and how recurring innate stimuli circumvent self-tolerance and initiate maladaptive autoimmunity is unknown. We explored if oxidized mitochondrial DNA (Ox-mtDNA), a DAMP released by stressed macrophages, found in higher amounts in diverse metabolic and autoimmune disorders, including systemic lupus erythematosus (SLE), initiates antibody-mediated autoimmunity. Indeed, Ox-mtDNA release induced by repetitive alum challenges elicited germinal center reactions, autoantibody production and nephropathology. These responses were recapitulated by in-vitro generated Ox-mtDNA, while non-oxidized mtDNA was non-pathogenic. Both mtDNA forms, but not nuclear DNA, were internalized by plasmacytoid dendritic cells (pDC), activated NF-kB via TLR9 and induced interferon (IFN)-I. Yet only Ox-mtDNA triggered NLRP3- and gasdermin D-dependent IL-1β secretion, eliciting autocrine production of IL-21 that together with IL-1β, but independently of IFN-I, enabled pDC to convert naïve CD4+ T cells into follicular helper cells. Highlighting Ox-mtDNA as a uniquely immunogenic DAMP that is specifically sensed by pDC and IL-1β as an orchestrator of autoantibody production, these findings explain how chronic inflammation culminates in autoimmunity and unravel new therapeutic targets applicable to SLE, the autoimmune/inflammatory syndrome induced by adjuvants (ASIA) and related diseases.
2025-04-10 | GSE264619 | GEO