Diminished OPA1 expression and impaired mitochondrial morphology and homeostasis in Aprataxin-deficient cells
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE124412 | GEO | 2018/12/28
REPOSITORIES: GEO
Similar Datasets
Project description:Ataxia with oculomotor apraxia type 1 (AOA1) is an early onset progressive spinocerebellar ataxia caused by mutation in aprataxin (APTX). Here we use RNA-seq to identify genes that are affected by APTX-KO, APTX overexpression, and APTX mutant, thus contributes to understadning the mechanisms underlying AOA1 pathlogy. Examination the chages of gene expressions in APTX proficient and APTX deficienc cells.
2018-12-28 | E-GEOD-124412 | biostudies-arrayexpress
Project description:Ataxia with oculomotor apraxia type 1 (AOA1) is an early onset progressive spinocerebellar ataxia caused by mutation in aprataxin (APTX). APTX removes 5´-AMP groups from DNA, a product of abortive ligation during DNA repair and replication. APTX deficiency has been suggested to compromise mitochondrial function; however, a detailed characterization of mitochondrial homeostasis in APTX-deficient cells is not available. Here we show that cells lacking APTX undergo mitochondrial stress and display significant changes in the expression of the mitochondrial inner membrane fusion protein OPA1, and components of the oxidative phosphorylation complexes. At the cellular level, APTX deficiency impairs mitochondrial morphology and network formation, and autophagic removal of damaged mitochondria by mitophagy. Thus, our results show that aberrant mitochondrial function is a key component of AOA1 pathology. This work corroborates the emerging evidence that impaired mitochondrial dynamics and mitophagy are at the hub of an increasing number of genetically diverse neurodegenerative disorders.
2019-05-21 | GSE114786 | GEO
Project description:Ataxia with oculomotor apraxia type 1 (AOA1) is a progressive neurodegenerative disorder characterized by a gradual loss of coordination of hand movements, speech, and eye movements. AOA1 is caused by inactivation mutation in the APTX gene.APTX resolves abortive DNA ligation intermediates. APTX deficiency may lead to the accumulation of 5'-AMP termini, especially in the mitochondrial genome. The consequences of APTX deficiency includes impaired mitochondrial function, increased DNA single-strand breaks, elevated reactive oxygen species production, and altered mitochondrial morphology. All of these processes can cause misplacement of nuclear and mitochondrial DNA, which can activate innate immune sensors to elicit an inflammatory response.This study explores the impact of APTX knockout in microglial cells, the immune cells of the brain. RNA-seq analysis revealed significant differences in the transcriptomes of wild-type and APTX knockout cells, especially in response to viral infections and innate immune pathways. Specifically, genes and proteins involved in the cGAS-STING and RIG-1/MAVS pathways were downregulated in APTX knockout cells, which suggests an impaired immune response to cytosolic DNA and RNA.The clinical relevance of these findings was supported by analyzing publicly available RNA-seq data from AOA1 patient cell lines. Comparisons between APTX-deficient patient cells and healthy control cells also revealed altered immune responses and dysregulated DNA-and RNA-sensing pathways in the patient cells.Overall, this study highlights the critical role of APTX in regulating innate immunity, particularly in DNA-and RNA-sensing pathways. Our findings contribute to a better 2 This is a provisional file, not the final typeset article understanding of the underlying molecular mechanisms of AOA1 pathology and highlights potential therapeutic targets for this disease.
2023-10-24 | GSE245766 | GEO
Project description:Mutations in the SETX gene, which encodes Senataxin, are associated with the progressive neurodegenerative diseases Ataxia with Oculomotor Apraxia 2 (AOA2) and Amyotrophic Lateral Sclerosis 4 (ALS4). To identify the causal defect in AOA2, patient-derived cells and SETX knockouts (human and mouse) were analyzed using integrated genomic and transcriptomic approaches. We observed a genome-wide increase in chromosome instability (gains and losses) within genes and at chromosome fragile sites, resulting in changes to gene expression profiles. Senataxin loss caused increased RNA polymerase II pausing events (transcription stress) near promoters that correlated with high GCskew and R-loop accumulation at promoter-proximal regions. Notably, the chromosomal regions with gains and losses overlapped with regions of elevated transcription stress. Aberrant R-loops were resolved by transcription-coupled repair (TCR), in reactions dependent upon the Cockayne Syndrome protein CSB. We found that CSB was required for the recruitment of the TCR endonucleases XPG and XPF, and recombination factors to target and resolve transcription bubbles containing R-loops and promote genomic instability. These results show that cells derived from individuals with Ataxia with Oculomotor Apraxia 2 exhibit transcription stress giving rise to genome-wide chromosomal fragility, termed transcription stress-induced fragile sites (TSFS), in transcribed regions of the mammalian genome.
2021-04-29 | GSE143680 | GEO
Project description:Mutations in the SETX gene, which encodes Senataxin, are associated with the progressive neurodegenerative diseases Ataxia with Oculomotor Apraxia 2 (AOA2) and Amyotrophic Lateral Sclerosis 4 (ALS4). To identify the causal defect in AOA2, patient-derived cells and SETX knockouts (human and mouse) were analyzed using integrated genomic and transcriptomic approaches. We observed a genome-wide increase in chromosome instability (gains and losses) within genes and at chromosome fragile sites, resulting in changes to gene expression profiles. Senataxin loss caused increased RNA polymerase II pausing events (transcription stress) near promoters that correlated with high GCskew and R-loop accumulation at promoter-proximal regions. Notably, the chromosomal regions with gains and losses overlapped with regions of elevated transcription stress. Aberrant R-loops were resolved by transcription-coupled repair (TCR), in reactions dependent upon the Cockayne Syndrome protein CSB. We found that CSB was required for the recruitment of the TCR endonucleases XPG and XPF, and recombination factors to target and resolve transcription bubbles containing R-loops and promote genomic instability. These results show that cells derived from individuals with Ataxia with Oculomotor Apraxia 2 exhibit transcription stress giving rise to genome-wide chromosomal fragility, termed transcription stress-induced fragile sites (TSFS), in transcribed regions of the mammalian genome.
2021-04-29 | GSE143573 | GEO
Project description:Mutations in the SETX gene, which encodes Senataxin, are associated with the progressive neurodegenerative diseases Ataxia with Oculomotor Apraxia 2 (AOA2) and Amyotrophic Lateral Sclerosis 4 (ALS4). To identify the causal defect in AOA2, patient-derived cells and SETX knockouts (human and mouse) were analyzed using integrated genomic and transcriptomic approaches. We observed a genome-wide increase in chromosome instability (gains and losses) within genes and at chromosome fragile sites, resulting in changes to gene expression profiles. Senataxin loss caused increased RNA polymerase II pausing events (transcription stress) near promoters that correlated with high GCskew and R-loop accumulation at promoter-proximal regions. Notably, the chromosomal regions with gains and losses overlapped with regions of elevated transcription stress. Aberrant R-loops were resolved by transcription-coupled repair (TCR), in reactions dependent upon the Cockayne Syndrome protein CSB. We found that CSB was required for the recruitment of the TCR endonucleases XPG and XPF, and recombination factors to target and resolve transcription bubbles containing R-loops and promote genomic instability. These results show that cells derived from individuals with Ataxia with Oculomotor Apraxia 2 exhibit transcription stress giving rise to genome-wide chromosomal fragility, termed transcription stress-induced fragile sites (TSFS), in transcribed regions of the mammalian genome.
2021-04-29 | GSE153577 | GEO
Project description:Mutations in the SETX gene, which encodes Senataxin, are associated with the progressive neurodegenerative diseases Ataxia with Oculomotor Apraxia 2 (AOA2) and Amyotrophic Lateral Sclerosis 4 (ALS4). To identify the causal defect in AOA2, patient-derived cells and SETX knockouts (human and mouse) were analyzed using integrated genomic and transcriptomic approaches. We observed a genome-wide increase in chromosome instability (gains and losses) within genes and at chromosome fragile sites, resulting in changes to gene expression profiles. Senataxin loss caused increased RNA polymerase II pausing events (transcription stress) near promoters that correlated with high GCskew and R-loop accumulation at promoter-proximal regions. Notably, the chromosomal regions with gains and losses overlapped with regions of elevated transcription stress. Aberrant R-loops were resolved by transcription-coupled repair (TCR), in reactions dependent upon the Cockayne Syndrome protein CSB. We found that CSB was required for the recruitment of the TCR endonucleases XPG and XPF, and recombination factors to target and resolve transcription bubbles containing R-loops and promote genomic instability. These results show that cells derived from individuals with Ataxia with Oculomotor Apraxia 2 exhibit transcription stress giving rise to genome-wide chromosomal fragility, termed transcription stress-induced fragile sites (TSFS), in transcribed regions of the mammalian genome.
2021-04-29 | GSE143570 | GEO
Project description:Mutations in the SETX gene, which encodes Senataxin, are associated with the progressive neurodegenerative diseases Ataxia with Oculomotor Apraxia 2 (AOA2) and Amyotrophic Lateral Sclerosis 4 (ALS4). To identify the causal defect in AOA2, patient-derived cells and SETX knockouts (human and mouse) were analyzed using integrated genomic and transcriptomic approaches. We observed a genome-wide increase in chromosome instability (gains and losses) within genes and at chromosome fragile sites, resulting in changes to gene expression profiles. Senataxin loss caused increased RNA polymerase II pausing events (transcription stress) near promoters that correlated with high GCskew and R-loop accumulation at promoter-proximal regions. Notably, the chromosomal regions with gains and losses overlapped with regions of elevated transcription stress. Aberrant R-loops were resolved by transcription-coupled repair (TCR), in reactions dependent upon the Cockayne Syndrome protein CSB. We found that CSB was required for the recruitment of the TCR endonucleases XPG and XPF, and recombination factors to target and resolve transcription bubbles containing R-loops and promote genomic instability. These results show that cells derived from individuals with Ataxia with Oculomotor Apraxia 2 exhibit transcription stress giving rise to genome-wide chromosomal fragility, termed transcription stress-induced fragile sites (TSFS), in transcribed regions of the mammalian genome.
2021-04-29 | GSE143566 | GEO
Project description:Mutations in the SETX gene, which encodes Senataxin, are associated with the progressive neurodegenerative diseases Ataxia with Oculomotor Apraxia 2 (AOA2) and Amyotrophic Lateral Sclerosis 4 (ALS4). To identify the causal defect in AOA2, patient-derived cells and SETX knockouts (human and mouse) were analyzed using integrated genomic and transcriptomic approaches. We observed a genome-wide increase in chromosome instability (gains and losses) within genes and at chromosome fragile sites, resulting in changes to gene expression profiles. Senataxin loss caused increased RNA polymerase II pausing events (transcription stress) near promoters that correlated with high GCskew and R-loop accumulation at promoter-proximal regions. Notably, the chromosomal regions with gains and losses overlapped with regions of elevated transcription stress. Aberrant R-loops were resolved by transcription-coupled repair (TCR), in reactions dependent upon the Cockayne Syndrome protein CSB. We found that CSB was required for the recruitment of the TCR endonucleases XPG and XPF, and recombination factors to target and resolve transcription bubbles containing R-loops and promote genomic instability. These results show that cells derived from individuals with Ataxia with Oculomotor Apraxia 2 exhibit transcription stress giving rise to genome-wide chromosomal fragility, termed transcription stress-induced fragile sites (TSFS), in transcribed regions of the mammalian genome.
2021-04-29 | GSE143558 | GEO
Project description:This SuperSeries is composed of the SubSeries listed below. Publication: D Janecki, R Sen, N Szóstak, A Kajdasz, M Kordys, K Plawgo, D Pandakov, A Philips, Z Warkocki (2024): LINE-1 mRNA 3’ end dynamics shape its biology and retrotransposition potential. Nucleic Acids Research. https://doi.org/10.1093/nar/gkad1251
2024-01-05 | GSE248109 | GEO