V-ATPase-mediated buffering of mitochondrial dysfunction
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE261899 | GEO | 2025/10/30
REPOSITORIES: GEO
Similar Datasets
Project description:v-ATPase-mediated buffering of mitochondrial dysfunction
| PRJNA1089540 | ENA
Project description:Mitochondrial defects are associated with a spectrum of human disorders, ranging from rare, inborn errors of metabolism to common, age-associated diseases such as diabetes and neurodegeneration. In lower organisms, genetic “retrograde” signaling programs have been identified that promote cellular and organism survival in the face of mitochondrial dysfunction. Here, we characterized the transcriptional component of the human mitochondrial retrograde response in an inducible model of mitochondrial dysfunction. We used an HEK293-derived cell line that expresses a dominant negative DNA polymerase gamma (PolGdn) under tet repressor control. Upon induction with doxycycline, PolGdn inhibits replication of mitochondrial DNA (mtDNA), so that existing copies of mtDNA are progressively diluted as cells continue to divide. Upon removal of doxycycline, repression of PolGdn is re-established, and mtDNA copy number, as well as mitochondrial protein expression and oxidative phosphorylation complex abundance, recovers. We used microarrays to study transcriptional changes arising from mtDNA depletion. We found a robust transcriptional response that is partially mediated by ATF4, which appears to effect an adaptive rewiring of serine and one-carbon metabolism.
2016-02-01 | GSE55311 | GEO
Project description:To investigate the immediate effect of HSP60 dysfunction on mitochondrial functions, we induced the expression of a dominant-negative ATPase-deficient HSP60 mutant (HSP60-D423A) in HEK293 cells using tetracycline . Incorporation of HSP60-D423A subunits into HSP60 heptamer rings leads to dysfunction of the chaperonin complex. We titrated tetracycline levels to have a biologically relevant cellular model that can be monitored over time. Expression of the HSP60-D432A protein resulted in significantly reduced cell counts at 72 hours induction compared to uninduced and HSP60-WT co-expressing cells. To study the effects of onset of HSP60 deficiency, we monitored transcriptional changes using RNASeq.
2024-09-27 | GSE254495 | GEO
Project description:Mitochondrial DNA (mtDNA) encodes essential components of the respiratory chain and loss of mtDNA leads to mitochondrial dysfunction and neurodegeneration. Mitochondrial transcription factor A (TFAM) is an essential component of mtDNA replication and a regulator of mitochondrial copy number in cells. Studies have shown that TFAM knockdown leads to mitochondrial dysfunction and respiratory chain deficiencies. Using gene expression analysis, we aimed to investigate the effects of mtDNA dysfunction in the CNS at the molecular level. We used microarray analysis to investigate gene expression in cases of mitochondrial dysfunction in the CNS. RNA was purified from the late third instar larval CNS from control larvae, or larvae over-expressing mitochondrial transcription factor A (TFAM) in post-mitotic neurons using the neuron specific driver nsyb-Gal4. Three replicates are included for each condition.
2013-12-20 | E-GEOD-53509 | biostudies-arrayexpress
Project description:Mitochondrial dysfunction is a hallmark of Parkinson’s disease (PD), but the mechanisms by which it drives autosomal dominant and idiopathic forms of PD remain unclear. To investigate this, we generated and performed a comprehensive phenotypic analysis of a knock-in mouse model carrying the T61I mutation in the mitochondrial protein CHCHD2, which causes late-onset symptoms indistinguishable from idiopathic PD. We observed pronounced mitochondrial disruption in substantia nigra (SN) dopaminergic neurons, including distorted ultrastructure and CHCHD2 aggregation, as well as disrupted mitochondrial protein-protein interactions in brain lysates. These abnormalities were associated with a whole-body metabolic shift towards glycolysis, elevated mitochondrial ROS, and progressive accumulation of aggregated α-synuclein. In idiopathic PD, CHCHD2 gene expression also correlated with α-synuclein levels in vulnerable dopaminergic neurons, and CHCHD2 protein accumulated in early Lewy aggregates. These findings delineate a pathogenic cascade in which CHCHD2 accumulation impairs mitochondrial respiration and increases ROS production, driving α-synuclein aggregation and neurodegeneration.
2025-10-02 | GSE309202 | GEO
Project description:Ageing is associated with a range of chronic diseases and has diverse hallmarks. Mitochondrial dysfunction is implicated in ageing, and mouse-models with artificially enhanced mitochondrial DNA (mtDNA) mutation rates show accelerated ageing. A scarcely studied aspect of ageing, because it is invisible in aggregate analyses, is the accumulation of somatic mtDNA mutations which are unique to single cells (cryptic mutations). We find evidence of cryptic mtDNA mutations from diverse single-cell datasets, from three species, and discover: cryptic mutations constitute the vast majority of mtDNA mutations in aged post-mitotic tissues, that they can avoid selection, that their accumulation is consonant with theory we develop, hitting high levels coinciding with species specific mid-late life, and that their presence covaries with a majority of the hallmarks of ageing including protein misfolding and ER stress. We identify mechanistic links to ER stress experimentally and further give an indication that aged brain cells with high levels of cryptic mutations show markers of neurodegeneration and that calorie restriction slows the accumulation of cryptic mutations.
2025-02-10 | GSE284767 | GEO
Project description:The mitochondrial network forms a central hub in cellular metabolism, adapting to a vast array of environmental and cellular signals to maintain cellular homeostasis. Derangements to this network can lead to mitochondrial diseases but are also increasingly recognised to be a contributing factor in common disorders including heart failure, neurodegeneration, cancer, or the natural ageing process. Despite its central importance, little is known how the cell responds to a mitochondrial dysfunction, contributing to our lack of affective treatment strategies. Here we performed an unbiased genetic deficiency screen in the fruit fly to identify mechanisms that can rescue a lethal mitochondrial dysfunction. After screening ~40% of the fly genome, we identified 10 genes from four distinct cellular pathways that rescued the mitochondrial dysfunction upon heterozygous deletion, resulting in viable adult flies. The data presented here includes proteomic analysis of larvae of control, mutant, and rescued lines.
2024-12-01 | PXD041418 | Pride
Project description:Mitochondrial dysfunction is a common feature in neurodegeneration and aging. We identify mitochondrial dysfunction in xeroderma pigmentosum group A (XPA), a nucleotide excision DNA repair disorder with severe neurodegeneration, in silico and in vivo. XPA deficient cells show defective mitophagy with excessive cleavage of PINK1 and increased mitochondrial membrane potential. The mitochondrial abnormalities appear to be caused by decreased activation of the NAD+-SIRT1-PGC-1α axis triggered by hyperactivation of the DNA damage sensor PARP1. This phenotype is rescued by PARP1 inhibition or by supplementation with NAD+ precursors that also rescue the lifespan defect in xpa-1 nematodes. Importantly, this pathogenesis appears common to ataxia-telangiectasia and Cockayne syndrome, two other DNA repair disorders with neurodegeneration, but absent in XPC, a DNA repair disorder without neurodegeneration. Our findings reveal a novel nuclear-mitochondrial cross-talk that is critical for the maintenance of mitochondrial health.
2015-06-04 | GSE55485 | GEO
Project description:Mitochondrial dysfunction is a common feature in neurodegeneration and aging. We identify mitochondrial dysfunction in xeroderma pigmentosum group A (XPA), a nucleotide excision DNA repair disorder with severe neurodegeneration, in silico and in vivo. XPA deficient cells show defective mitophagy with excessive cleavage of PINK1 and increased mitochondrial membrane potential. The mitochondrial abnormalities appear to be caused by decreased activation of the NAD+-SIRT1-PGC-1α axis triggered by hyperactivation of the DNA damage sensor PARP1. This phenotype is rescued by PARP1 inhibition or by supplementation with NAD+ precursors that also rescue the lifespan defect in xpa-1 nematodes. Importantly, this pathogenesis appears common to ataxia-telangiectasia and Cockayne syndrome, two other DNA repair disorders with neurodegeneration, but absent in XPC, a DNA repair disorder without neurodegeneration. Our findings reveal a novel nuclear-mitochondrial cross-talk that is critical for the maintenance of mitochondrial health.
2015-06-04 | GSE55484 | GEO
Project description:Mitochondrial dysfunction is a common feature in neurodegeneration and aging. We identify mitochondrial dysfunction in xeroderma pigmentosum group A (XPA), a nucleotide excision DNA repair disorder with severe neurodegeneration, in silico and in vivo. XPA deficient cells show defective mitophagy with excessive cleavage of PINK1 and increased mitochondrial membrane potential. The mitochondrial abnormalities appear to be caused by decreased activation of the NAD+-SIRT1-PGC-1? axis triggered by hyperactivation of the DNA damage sensor PARP1. This phenotype is rescued by PARP1 inhibition or by supplementation with NAD+ precursors that also rescue the lifespan defect in xpa-1 nematodes. Importantly, this pathogenesis appears common to ataxia-telangiectasia and Cockayne syndrome, two other DNA repair disorders with neurodegeneration, but absent in XPC, a DNA repair disorder without neurodegeneration. Our findings reveal a novel nuclear-mitochondrial cross-talk that is critical for the maintenance of mitochondrial health. Mice carrying WT, or CX (Csa-/-/Xpa-/-) alleles in a C57BL/6 background were maintained under standard laboratory conditions and allowed free access to water and control casein pelleted diet (Research Diets D12450B). At 3 months of age, 3 replicates of each of the CX and WT mice were given subcutaneous interscapular injections of 500 mg of Nicotinamide riboside/kg body weight/day or the equivalent volume of saline for 14 consecutive days at 4:00 pm. On day 15, the mice were sacrificed and half of the cerebellum was harvested for purification of mitochondria, with the left half snap-frozen, homogenized, and aliquoted for RNA isolation. Total RNA extraction was done using a TRIzol Plus RNA purification kit as per manufacturer’s protocol. Quality and quantity of the total RNA was tested using the Agilent 2100 Bio-Analyzer and RNA 6000 nano kits. The RNA was labeled using the standard Illumina protocol and hybed overnight to Mouse Ref-8 Illumina arrays. The arrays were scanned using the Beadstation 500 X from Illumina.
2015-06-04 | E-GEOD-55485 | biostudies-arrayexpress