Gene expression profile at single cell level of retinal cells of mitochondrial ND6 13997 G>A mutant mouse
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
PROVIDER: GSE280785 | GEO | 2025/04/22
REPOSITORIES: GEO
Similar Datasets
Project description:The genetic defects leading to optic atrophy range from mitochondrial DNA (mtDNA) point mutations in Leber’s hereditary optic neuropathy (LHON), to dominant and recessive mutations affecting a cluster of nuclear genes implicated in mitochondrial dynamics. We performed WES in patients with an optic atrophy spectrum disorder, including retinal macular dystrophy and kidney insufficiency leading to transplantation, associated with mitochondrial DNA (mtDNA) depletion without accumulation of multiple deletions, to identify the genetic causes of this syndrome.
| EGAS00001003850 | EGA
Project description:Leber hereditary optic neuropathy (LHON) is one of the most common primary mitochondrial diseases. It is caused by point mutations in mitochondrial DNA (mtDNA) genes and in some cases, it can result in irreversible vision loss, primarily in young men. It is currently unknown why LHON mutations affect only some carriers and whether bioenergetic compensation enables asymptomatic carriers to overcome mitochondrial impairment and preserve cellular function. Here, we conducted bioenergetic metabolic assays and RNA sequencing to address this question using male-only, age-matched, m.11778G>A lymphoblasts and primary fibroblasts from both carriers and affected individuals. Our work indicates that OXPHOS bioenergetic compensation in LHON peripheral cells does not explain disease phenotype. We show that complex I impairment is similar in carrier and affected cells, despite a transcriptional downregulation of metabolic pathways including glycolysis in affected cells relative to carriers detected by RNA sequencing. Although we did not detect OXPHOS bioenergetic compensation in carrier cells, our results indicate that affected cells suffer a growth impairment under metabolic challenge compared to carrier cells, which were unaffected by metabolic challenge. If recapitulated in retinal ganglion cells, decreased susceptibility to metabolic challenge in carriers may help preserve metabolic homeostasis in the face of the mitochondrial complex I bioenergetic defect.
2020-02-08 | GSE144914 | GEO
Project description:Leber’s hereditary optic neuropathy (LHON) is a maternally inherited mitochondrial disease caused by homoplasmic mutations in complex I subunit genes, and is characterized by incomplete penetrance. The mechanism of low penetrance of complex I mutation is still largely unclear today. In this study, we created the patient-specific induced pluripotent stem cells (iPSCs) from MT-ND4 mutated LHON affected patient, asymptomatic mutation carrier and control, and differentiated them into retinal ganglion cells (RGCs) for pathogenesis survey. We observed the following phenotypic features in the LHON-specific RGCs as compared to the control: 1) enhanced mitochondrial biogenesis in affected and carriers; 2) compensatory increased mitochondrial complex I activity in carrier, but not in affected patient; 3) reduced spare respiratory activity in affected and carrier. Microarray profiling of LHON-specific RGCs revealed abundant overexpression of genes encoding components of cell cycle regulation machinery as compared to the control.
2017-09-08 | GSE103619 | GEO
Project description:Autosomal optic atrophy (AOA) is a form of hereditary optic neuropathy characterized by the irreversible and progressive degermation of the retinal ganglion cells. Most cases of AOA are associated with a single dominant mutation in OPA1, which encodes a protein required for fusion of the inner mitochondrial membrane. It is unclear how loss of OPA1 leads to neuronal death, and despite ubiquitous expression appears to disproportionately affect the RGCs. This study introduces two novel in vivo models of OPA1-mediated AOA, including the first developmentally viable vertebrate Opa1 knockout (KO). These models allow for the study of Opa1 loss in neurons, specifically RGCs. Though survival is significantly reduced in Opa1 deficient zebrafish and Drosophila, both models permit the study of viable larvae. Moreover, zebrafish Opa1 KO larvae show impaired visual function but unchanged locomotor function, indicating that retinal neurons are particularly sensitive to Opa1 loss. Proteomic profiling of both models reveals marked disruption in protein expression associated with mitochondrial function, consistent with an observed decrease in mitochondrial respiratory function. Similarly, mitochondrial fragmentation and disordered cristae organization were observed in neuronal axons in both models highlighting Opa1’s highly conserved role in regulating mitochondrial morphology and function in neuronal axons. Importantly, in Opa1 deficient zebrafish, mitochondrial disruption and visual impairment precede degeneration of RGCs. These novel models mimic key features of AOA and provide valuable tools for therapeutic screening. Our findings suggest that therapies enhancing mitochondrial function may offer a potential treatment strategy for AOA.
2025-05-07 | PXD059584 | Pride
Project description:Autosomal optic atrophy (AOA) is a form of hereditary optic neuropathy characterized by the irreversible and progressive degermation of the retinal ganglion cells. Most cases of AOA are associated with a single dominant mutation in OPA1, which encodes a protein required for fusion of the inner mitochondrial membrane. It is unclear how loss of OPA1 leads to neuronal death, and despite ubiquitous expression appears to disproportionately affect the RGCs. This study introduces two novel in vivo models of OPA1-mediated AOA, including the first developmentally viable vertebrate Opa1 knockout (KO). These models allow for the study of Opa1 loss in neurons, specifically RGCs. Though survival is significantly reduced in Opa1 deficient zebrafish and Drosophila, both models permit the study of viable larvae. Moreover, zebrafish Opa1 KO larvae show impaired visual function but unchanged locomotor function, indicating that retinal neurons are particularly sensitive to Opa1 loss. Proteomic profiling of both models reveals marked disruption in protein expression associated with mitochondrial function, consistent with an observed decrease in mitochondrial respiratory function. Similarly, mitochondrial fragmentation and disordered cristae organization were observed in neuronal axons in both models highlighting Opa1’s highly conserved role in regulating mitochondrial morphology and function in neuronal axons. Importantly, in Opa1 deficient zebrafish, mitochondrial disruption and visual impairment precede degeneration of RGCs. These novel models mimic key features of AOA and provide valuable tools for therapeutic screening. Our findings suggest that therapies enhancing mitochondrial function may offer a potential treatment strategy for AOA.
2025-05-07 | PXD059645 | Pride
Project description:Objective: Pathological retinal angiogenesis is vision threatening. In mouse oxygen-induced retinopathy (OIR) we sought to define mitochondrial respiration changes longitudinally during hyperoxia-induced vessel loss and with hypoxia-induced neovascularization (NV), and test interventions to address those changes to prevent NV. Methods: OIR was induced in C57BL/6J mice and retinal vasculature was examined at maximum neovessel formation. We assessed total proteome change and the ratio of mitochondrial/nuclear DNA copy numbers (mtDNA/nDNA) of OIR vs. control retinas, and mitochondrial oxygen consumption rates (OCR) in ex vivo OIR vs. control retinas (BaroFuse). Pyruvate vs. vehicle control was supplemented in OIR mice either prior to or during neovessel formation. Results: In OIR vs. control retinas proteomics identified decreased retinal mitochondrial respiration and synaptic formation pathway proteins at peak neovascularization. mtDNA/nDNA was decreased during hypoxia-induced neovessel growth (as was OCR) suggesting impaired mitochondrial respiration. Pyruvate administration during but not prior to neovessel formation (in line with compromised mitochondrial activity) suppressed NV in vivo. Conclusions: Mitochondrial energetics are suppressed during retinal NV in OIR. Appropriately timed supplementation of energy substrates (pyruvate) may be a novel approach in neovascular retinal diseases.
2025-05-06 | PXD051410 | Pride
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:Glaucoma is an optic neuropathy characterized by progressive degeneration of retinal ganglion cells (RGCs) and visual loss. Previous studies have reported that the variation of the ATP-binding cassette transporter 1 (ABCA1) gene is linked to a higher risk of glaucoma in humans, but the pathological mechanisms remain unknown. Here we report that ABCA1 loss, especially in astrocytes, causes optic neuropathy. ABCA1 was mainly expressed in astrocytes rather than neurons, and that knockout of Abca1 gene under GFAP promoter (Glia-KO) caused age-associated RGC degeneration and ocular dysfunction without affecting intraocular pressure, a major risk factor for glaucoma. Glia-KO mice showed age-associated changes in astrocyte reactivity accompanied by the accumulation of cholesterol, a major substrate of ABCA1. Single-cell RNA sequencing revealed that Abca1 deficiency causes astrocyte-triggered inflammation and increased sensitivity of RGCs against excitotoxicity. Altogether, these findings suggest that astrocytic dysfunction caused by ABCA1 loss triggers age-associated optic neuropathy-like pathology.
2022-07-11 | GSE207929 | GEO
Project description:Glaucoma is an optic neuropathy characterized by progressive degeneration of retinal ganglion cells (RGCs) and visual loss. Previous studies have reported that the variation of the ATP-binding cassette transporter 1 (ABCA1) gene is linked to a higher risk of glaucoma in humans, but the pathological mechanisms remain unknown. Here we report that ABCA1 loss, especially in astrocytes, causes optic neuropathy. ABCA1 was mainly expressed in astrocytes rather than neurons, and that knockout of Abca1 gene under GFAP promoter (Glia-KO) caused age-associated RGC degeneration and ocular dysfunction without affecting intraocular pressure, a major risk factor for glaucoma. Glia-KO mice showed age-associated changes in astrocyte reactivity accompanied by the accumulation of cholesterol, a major substrate of ABCA1. Single-cell RNA sequencing revealed that Abca1 deficiency causes astrocyte-triggered inflammation and increased sensitivity of RGCs against excitotoxicity. Altogether, these findings suggest that astrocytic dysfunction caused by ABCA1 loss triggers age-associated optic neuropathy-like pathology.
2022-07-11 | GSE207928 | GEO