Genetic interaction screen for FXN in K562 cells, to identify genes that are synthetic sick/buffering in the absence of robust Fe-S cluster synthesis
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE242192 | GEO | 2023/12/18
REPOSITORIES: GEO
Similar Datasets
Project description:Friedreich’s ataxia (FA) is the most common monogenic mitochondrial disease. FA is caused by a depletion of the mitochondrial protein frataxin (FXN), an iron-sulfur (Fe-S) cluster biogenesis factor. To better understand the cellular consequences of FA, we performed quantitative proteome profiling of human cells depleted for FXN. Nearly every known Fe-S cluster-containing protein was depleted in the absence of FXN, indicating that as a rule, cluster binding confers stability to Fe-S proteins. Proteomic and genetic interaction mapping identified impaired mitochondrial translation downstream of FXN loss, and specifically highlighted the methyltransferase-like protein METTL17 as a candidate effector. Using comparative sequence analysis, mutagenesis, biochemistry and cryogenic electron microscopy we show that METTL17 binds to the mitoribosomal small subunit during late assembly and harbors a previously unrecognized [Fe4S4]2+ cluster required for its stability on the mitoribosome. Notably, METTL17 overexpression rescued the mitochondrial translation and bioenergetic defects, but not the cellular growth, of FXN depleted cells. Our data suggest that METTL17 serves as an Fe-S cluster checkpoint: promoting the translation and assembly of Fe-S cluster rich OXPHOS proteins only when Fe-S cluster levels are replete.
2023-12-27 | PXD045443 | Pride
Project description:The inherited neurodegenerative disease Friedreich’s ataxia (FRDA) is caused by hyperexpansion of GAA•TTC trinucleotide repeats within the first intron of the FXN gene, encoding the mitochondrial protein frataxin. Long GAA•TTC repeats causes heterochromatin-mediated silencing and loss of frataxin in affected individuals. We report the derivation of induced pluripotent stem cells (iPSCs) from FRDA patient fibroblasts through retroviral transduction of transcription factors. FXN gene repression is maintained in the iPSCs, as are the mRNA and miRNA global expression signatures reflecting the human disease. GAA•TTC repeats uniquely in FXN in the iPSCs exhibit repeat instability similar to patient families, where they expand and/or contract with discrete changes in length between generations. The mismatch repair enzyme Msh2, implicated in repeat instability in other triplet repeat diseases, is highly expressed in the iPSCs, occupies FXN intron 1, and shRNA silencing of Msh2 impedes repeat expansion, providing a possible molecular explanation for repeat expansion in FRDA.
2010-07-02 | GSE22651 | GEO
Project description:Frataxin, a conserved mitochondrial protein involved in iron homeostasis, is reduced in patients with Friedreich’s ataxia (FRDA). Transcription profiling and DNA damage assays were performed on blood cells from FRDA patients. Altered expression patterns pertained to immune response, signaling pathways, transcription, apoptosis, and genotoxic stress response pathways. FRDA patients had significantly more mitochondrial and nuclear DNA damage than a control population. Frataxin mRNA levels correlated with age of onset and displayed unique sets of gene alterations involved in oxidative phosphorylation and protein synthesis. Thus analysis of blood in FRDA patients yields insight into the nature and progression of the disease, as well as potential therapeutic approaches. Keywords: Friedreich's ataxia; frataxin; mitochondrial DNA damage; nuclear DNA damage; genotoxic stress
2009-12-08 | GSE11204 | GEO
Project description:Frataxin (FXN) is involved in mitochondrial iron-sulfur (Fe-S) cluster biogenesis and serves to accelerate Fe-S cluster formation. FXN deficiency is associated with Friedreich ataxia, a neurodegenerative disease. Using chemical cross-linking (XL) accompanied with LC-MS/MS, we studied the the interaction between the core complexes Acp-ISD11-NFS1 (AIN) and AIN-ISCU (AINU) with FXN.
2018-07-11 | PXD006928 | Pride
Project description:Frataxin (FXN) is involved in mitochondrial iron-sulfur (Fe-S) cluster biogenesis and serves to accelerate Fe-S cluster formation. FXN deficiency is associated with Friedreich ataxia, a neurodegenerative disease. Using chemical cross-linking (XL) accompanied with LC-MS/MS, we studied the the interaction between the core complexes Acp-ISD11-NFS1 (AIN) and AIN-ISCU (AINU) with FXN.
2018-07-11 | PXD006938 | Pride
Project description:The inherited neurodegenerative disease Friedreichâ??s ataxia (FRDA) is caused by hyperexpansion of GAAâ?¢TTC trinucleotide repeats within the first intron of the FXN gene, encoding the mitochondrial protein frataxin. Long GAAâ?¢TTC repeats causes heterochromatin-mediated silencing and loss of frataxin in affected individuals. We report the derivation of induced pluripotent stem cells (iPSCs) from FRDA patient fibroblasts through retroviral transduction of transcription factors. FXN gene repression is maintained in the iPSCs, as are the mRNA and miRNA global expression signatures reflecting the human disease. GAAâ?¢TTC repeats uniquely in FXN in the iPSCs exhibit repeat instability similar to patient families, where they expand and/or contract with discrete changes in length between generations. The mismatch repair enzyme Msh2, implicated in repeat instability in other triplet repeat diseases, is highly expressed in the iPSCs, occupies FXN intron 1, and shRNA silencing of Msh2 impedes repeat expansion, providing a possible molecular explanation for repeat expansion in FRDA. 65 samples from various number of tissue, primary cell lines undifferenatiated human embryonic stem cell lines, induces pluripotent stem cell lines have been run on Illumina HT12 v3 chips.
2010-07-30 | E-GEOD-22651 | biostudies-arrayexpress
Project description:Friedreich ataxia is a neuro and cardio degenerative disease, caused by progressive, decreased expression of the frataxin gene (FXN). Hyperthrophic cardiomyopathy is the major cause of early mortality. We used four different lines of human, Induced Pluripotent Stem Cells derived- cardiomyocytes which were transfected with an siRNA against frataxin post-differentiation. Trascriptome analysis of cells in which frataxin was knocked down vs cells transfected with a si control RNA allowed the identification of novel pathways that may contribute to the pathogenesis of the disease.
2022-11-02 | E-MTAB-11296 | biostudies-arrayexpress
Project description:Friedreich's ataxia (FRDA), the most common inherited ataxia in humans, is caused by recessive mutations that lead to a substantial reduction in the levels of frataxin (FXN), a mitochondrial iron binding protein. FRDA is a multi-system disease, involving multiple neurological, cardiac, and metabolic manifestations whose study is hindered by a paucity of animal models that faithfully recapitulate human disease features. We developed an inducible (doxycycline) mouse model of Fxn deficiency (FRDAkd) that enabled us to control the onset, progression and potential rescue of disease phenotypes by the modulation of Fxn levels using RNA interference. We found that systemic knockdown of Fxn in adult mice led to multiple features paralleling those observed in human patients, including electrophysiological, cellular, biochemical and structural phenotypes associated with cardiomyopathy, as well as dorsal root ganglion and retinal neuronal degeneration and reduced axonal size and myelin sheath thickness in the spinal cord. Fxn knockdown mice also exhibited other abnormalities similar to patients, including weight loss, reduced locomotor activity, ataxia, reduced muscular strength, and reduced survival, as well as genome-wide transcriptome changes. We performed microarray analysis of heart, cerebellum and dorsal root ganglia in FRDAkd mouse model of frataxin deficiency, and found several molecular pathway dysfunction via genome-wide transcriptome analyses. We also found that, upon restoration of near wild-type FXN levels, we observed significant recovery of function, pathology and associated transcriptomic changes, even after significant motor dysfunction was observed. The rapidity of Fxn expression due to doxycycline removal and its robust correction of various parameters, even when restored after the onset of motor dysfunction, makes this FRDAkd mouse model an appealing potential preclinical tool for testing various therapeutics for FRDA.
2017-12-19 | GSE98790 | GEO
Project description:Friedreich’s ataxia (FRDA) is an autosomal recessive neurodegenerative disease usually caused by large homozygous expansions of GAA repeat sequences in intron 1 of the frataxin (FXN) gene. FRDA patients have low FXN mRNA and frataxin protein levels when compared with heterozygous carriers or healthy controls. Presently, there is no effective treatment for FRDA, and biomarkers to measure therapeutic trial outcomes and/or to gauge disease progression are lacking. Peripheral tissues, including blood cells, buccal cells, and skin fibroblasts, can readily be isolated from FRDA patients and used to define molecular hallmarks of disease pathogenesis. However, because these tissues are not directly involved in disease pathogenesis, their relevance as models of the molecular aspects of the disease is yet to be decided. Transcriptome profiling of FRDA skin fibroblasts revealed significantly upregulated expression of genes encoding plasma membrane solute carrier proteins. Conversely, the expression of genes encoding accessory factors and enzymes involved in cytoplasmic and mitochondrial protein synthesis was consistently decreased in the FRDA cells. Finally, comparison of genes differentially expressed in FRDA fibroblasts to 3 previously published gene expression signatures defined for FRDA blood cells showed substantial overlap between the independent datasets, including correspondingly deficient expression of antioxidant defense genes. Together, these results indicate that gene expression profiling of cells derived from peripheral tissues can, in fact, consistently reveal novel molecular pathways of the disease.
2017-09-27 | GSE104288 | GEO
Project description:Friedreich ataxia (FRDA) is a multisystemic, autosomal recessive disorder caused by a homozygous GAA expansion mutation in the first intron of frataxin (FXN) gene. FXN is a mitochondrial protein critical for iron-sulfur cluster biosynthesis and deficiency impairs mitochondrial electron transport chain functions and iron homeostasis within the organelle. Currently, there is no effective treatment for FRDA. We have previously demonstrated that a single infusion of wild-type hematopoietic stem and progenitor cells (HSPCs) resulted in the prevention of the neurologic and cardiac complications of FRDA in YG8R mice, and the rescue was mediated by FXN transfer from tissue engrafted HSPC-derived microglia/macrophages to diseased neurons/myocytes. For a future clinical translation of this approach, we developed an autologous stem cell transplantation approach using CRISPR/Cas9 for the excision of the GAA repeats in FRDA patients’ CD34+ HSPCs; this strategy leading to increased FXN expression and improved mitochondrial functions in the cells. The aim of the current study is to validate the efficiency and safety of our gene editing approach in a disease-relevant model. To this end, we generated a cohort of FRDA patient-derived iPSCs and isogenic lines that were gene edited with our CRISPR/Cas9 approach. FRDA neurons generated from these iPSCs displayed characteristic apoptotic and mitochondrial phenotype of the disease, such as non-homogenous microtubule staining in neurites, increased caspase-3 expression, mitochondrial superoxide levels, mitochondrial fragmentation, and partial degradation of the cristae compared to healthy controls. These defects were fully prevented in the gene edited neurons. RNASeq analysis of FRDA and gene edited neurons demonstrated striking improvement in gene clusters associated with endoplasmic reticulum (ER) stress in the isogenic lines. These results were validated by molecular and functional studies, and gene edited neurons demonstrated improved ER-calcium release, normalization of ER stress response gene, XBP-1, and significantly increased ER-mitochondrial contacts that are critical for functional homeostasis of both organelles, as compared to FRDA neurons. Ultrastructural analysis for these contact sites displayed severe structural damage to the ER in FRDA neurons, that was undetected in gene edited neurons. Taken together, these results represent a novel finding for disease pathogenesis showing dramatic ER structural damage and function in FRDA. In addition, these results validate the efficacy profile of our FXN gene editing approach, in a disease relevant model improving mitochondrial and cellular, and supporting our approach as an effective strategy for therapeutic intervention for Friedreich’s ataxia.
2024-01-29 | GSE244886 | GEO