A kinetic dichotomy between mitochondrial and nuclear gene expression processes
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE224163 | GEO | 2024/03/18
REPOSITORIES: GEO
Similar Datasets
Project description:Oxidative phosphorylation (OXPHOS) complexes consist of nuclear- and mitochondrial- encoded subunits, forcing cross-compartment synchronization of gene expression to achieve mitonuclear balance. To characterize how human cells coordinate OXPHOS gene expression, we establish a mitoribosome profiling approach that resolves features of the mitochondrial translatome, including the synthesis of a four amino acid mitopeptide. Strikingly, average mitochondrial and cytoplasmic synthesis rates correspond precisely across OXPHOS complexes. Coordinated mitochondrial and cytosolic synthesis does not require rapid feedback between the two translation systems. By contrast, we find that the Leigh syndrome gene, LRPPRC, maintains correlated mitochondrial and cytosolic translatomes. Our results lead to a model of human mitonuclear balance that requires tightly balanced cross-compartment protein synthesis, representing a vulnerability for cellular proteostasis.
2021-05-30 | GSE173283 | GEO
Project description:In all biological systems, RNAs are associated with RNA-binding proteins (RBPs), forming complexes that control gene regulatory mechanisms, from RNA synthesis to decay. In mammalian mitochondria, post-transcriptional regulation of gene expression is conducted by mitochondrial RBPs (mt-RBPs) at various stages of mt-RNA metabolism, including polycistronic transcript production, its processing into individual transcripts, mt-RNA modifications, stability, translation, and degradation. To date, only a handful of mt-RBPs have been characterized. Here, we describe a putative human mitochondrial protein, C6orf203, that contains an S4-like domain - an evolutionarily conserved RNA-binding domain previously identified in proteins involved in translation. Our data show C6orf203 to bind highly-structured RNA in vitro and associate with the mitoribosomal large subunit in HEK293T cells. Knockout of C6orf203 leads to a decrease in mitochondrial translation and consequent OXPHOS deficiency, without affecting mitochondrial RNA levels. Although mitoribosome stability is not affected in C6orf203-depleted cells, mitoribosome profiling analysis revealed a global disruption of the association of mt-mRNAs with the mitoribosome, suggesting that C6orf203 may be required for the proper maturation and functioning of the mitoribosome. We therefore propose C6orf203 to be a novel RNA-binding protein involved in mitochondrial translation, expanding the repertoire of factors engaged in this process.
2019-08-10 | GSE133315 | GEO
Project description:Mitochondrial oxidative phosphorylation (OXPHOS) complexes are assembled from proteins encoded by both nuclear and mitochondrial DNA. These dual-origin enzymes pose a complex gene regulatory challenge for cells requiring coordinated gene expression across organelles. To identify genes involved in dual-origin protein complex synthesis, we performed FACS-based genome-wide screens analyzing mutant cells with unbalanced levels of mitochondrial- and nuclear-encoded subunits of Complex IV. We identified novel genes involved in OXPHOS biogenesis, including two uncharacterized genes: PREPL and NME6. We found that PREPL specifically impacts Complex IV biogenesis by acting at the intersection of mitochondrial lipid metabolism and protein synthesis, while NME6, an uncharacterized nucleoside diphosphate kinase (NDPK), controls OXPHOS biogenesis through multiple mechanisms reliant on its NDPK domain. First, NME6 forms a complex with RCC1L, which together perform NDPK activity to maintain local mitochondrial pyrimidine triphosphate levels essential for mitochondrial RNA abundance. Second, NME6 modulates the activity of mitoribosome regulatory complexes, altering mitoribosome assembly and mitochondrial RNA pseudouridylation. Taken together, we propose that NME6 acts as a link between compartmentalized mitochondrial metabolites and mitochondrial gene expression.
2023-08-17 | GSE224818 | GEO
Project description:Mitochondrial oxidative phosphorylation (OXPHOS) complexes are assembled from proteins encoded by both nuclear and mitochondrial DNA. These dual-origin enzymes pose a complex gene regulatory challenge for cells requiring coordinated gene expression across organelles. To identify genes involved in dual-origin protein complex synthesis, we performed FACS-based genome-wide screens analyzing mutant cells with unbalanced levels of mitochondrial- and nuclear-encoded subunits of Complex IV. We identified novel genes involved in OXPHOS biogenesis, including two uncharacterized genes: PREPL and NME6. We found that PREPL specifically impacts Complex IV biogenesis by acting at the intersection of mitochondrial lipid metabolism and protein synthesis, while NME6, an uncharacterized nucleoside diphosphate kinase (NDPK), controls OXPHOS biogenesis through multiple mechanisms reliant on its NDPK domain. First, NME6 forms a complex with RCC1L, which together perform NDPK activity to maintain local mitochondrial pyrimidine triphosphate levels essential for mitochondrial RNA abundance. Second, NME6 modulates the activity of mitoribosome regulatory complexes, altering mitoribosome assembly and mitochondrial RNA pseudouridylation. Taken together, we propose that NME6 acts as a link between compartmentalized mitochondrial metabolites and mitochondrial gene expression.
2023-08-17 | GSE240576 | GEO
Project description:Mitochondrial oxidative phosphorylation (OXPHOS) complexes are assembled from proteins encoded by both nuclear and mitochondrial DNA. These dual-origin enzymes pose a complex gene regulatory challenge for cells requiring coordinated gene expression across organelles. To identify genes involved in dual-origin protein complex synthesis, we performed FACS-based genome-wide screens analyzing mutant cells with unbalanced levels of mitochondrial- and nuclear-encoded subunits of Complex IV. We identified novel genes involved in OXPHOS biogenesis, including two uncharacterized genes: PREPL and NME6. We found that PREPL specifically impacts Complex IV biogenesis by acting at the intersection of mitochondrial lipid metabolism and protein synthesis, while NME6, an uncharacterized nucleoside diphosphate kinase (NDPK), controls OXPHOS biogenesis through multiple mechanisms reliant on its NDPK domain. First, NME6 forms a complex with RCC1L, which together perform NDPK activity to maintain local mitochondrial pyrimidine triphosphate levels essential for mitochondrial RNA abundance. Second, NME6 modulates the activity of mitoribosome regulatory complexes, altering mitoribosome assembly and mitochondrial RNA pseudouridylation. Taken together, we propose that NME6 acts as a link between compartmentalized mitochondrial metabolites and mitochondrial gene expression.
2023-08-17 | GSE224817 | GEO
Project description:Mitochondrial oxidative phosphorylation (OXPHOS) complexes are assembled from proteins encoded by both nuclear and mitochondrial DNA. These dual-origin enzymes pose a complex gene regulatory challenge for cells requiring coordinated gene expression across organelles. To identify genes involved in dual-origin protein complex synthesis, we performed fluorescence-activated cell-sorting-based genome-wide screens analysing mutant cells with unbalanced levels of mitochondrial- and nuclear-encoded subunits of Complex IV. We identified genes involved in OXPHOS biogenesis, including two uncharacterized genes: PREPL and NME6. We found that PREPL specifically impacts Complex IV biogenesis by acting at the intersection of mitochondrial lipid metabolism and protein synthesis, whereas NME6, an uncharacterized nucleoside diphosphate kinase, controls OXPHOS biogenesis through multiple mechanisms reliant on its NDPK domain. Firstly, NME6 forms a complex with RCC1L, which together perform nucleoside diphosphate kinase activity to maintain local mitochondrial pyrimidine triphosphate levels essential for mitochondrial RNA abundance. Secondly, NME6 modulates the activity of mitoribosome regulatory complexes, altering mitoribosome assembly and mitochondrial RNA pseudouridylation. Taken together, we propose that NME6 acts as a link between compartmentalized mitochondrial metabolites and mitochondrial gene expression.
2023-08-17 | GSE224503 | GEO
Project description:<p> Human disorders of mitochondrial oxidative phosphorylation (OXPHOS) represent a devastating collection of inherited diseases. These disorders impact at least 1:5000 live births, and are characterized by multi-organ system involvement. They are characterized by remarkable locus heterogeneity, with mutations in the mtDNA as well as in over 77 nuclear genes identified to date. It is estimated that additional genes may be mutated in these disorders. </p> <p>To discover the genetic causes of mitochondrial OXPHOS diseases, we performed targeted, deep sequencing of the entire mitochondrial genome (mtDNA) and the coding exons of over 1000 nuclear genes encoding the mitochondrial proteome. We applied this 'MitoExome' sequencing to 124 unrelated patients with a wide range of OXPHOS disease presentations from the Massachusetts General Hospital Mitochondrial Disorders Clinic. </p> <p>The 2.3Mb targeted region was captured by hybrid selection and Illumina sequenced with paired 76bp reads. The total set of 1605 targeted nuclear genes included 1013 genes with strong evidence of mitochondrial localization from the MitoCarta database, 377 genes with weaker evidence of mitochondrial localization from the MitoP2 database and other sources, and 215 genes known to cause other inborn errors of metabolism. Approximately 88% of targeted bases were well-covered (>20X), with mean 200X coverage per targeted base. </p>
| phs000339 | dbGaP
Project description:Mitochondrial oxidative phosphorylation (OXPHOS) complexes are assembled from proteins encoded by both nuclear and mitochondrial DNA. These dual-origin enzymes pose a complex gene regulatory challenge for cells requiring coordinated gene expression across organelles. To identify genes involved in dual-origin protein complex synthesis, we performed FACS-based genome-wide screens analyzing mutant cells with unbalanced levels of mitochondrial- and nuclear-encoded subunits of Complex IV. We identified novel genes involved in OXPHOS biogenesis, including two uncharacterized genes: PREPL and NME6. We found that PREPL specifically impacts Complex IV biogenesis by acting at the intersection of mitochondrial lipid metabolism and protein synthesis, while NME6, an uncharacterized nucleoside diphosphate kinase (NDPK), controls OXPHOS biogenesis through multiple mechanisms reliant on its NDPK domain. First, NME6 forms a complex with RCC1L, which together perform NDPK activity to maintain local mitochondrial pyrimidine triphosphate levels essential for mitochondrial RNA abundance. Second, NME6 modulates the activity of mitoribosome regulatory complexes, altering mitoribosome assembly and mitochondrial RNA pseudouridylation. Taken together, we propose that NME6 acts as a link between compartmentalized mitochondrial metabolites and mitochondrial gene expression.
2023-08-23 | PXD044812 | Pride
Project description:Rapid advances in genotyping and sequencing technology have dramatically accelerated the discovery of genes underlying human disease. Elucidating the function of such genes and understanding their role in pathogenesis, however, remains challenging. Here, we introduce a genomic strategy to functionally characterize such genes, and apply it to LRPPRC (leucine-rich PPR-motif containing), a poorly studied gene that is mutated in Leigh Syndrome, French Canadian type (LSFC). We utilize RNAi to engineer an allelic series of cellular models in which LRPPRC has been stably silenced to different levels of knockdown efficiency. Using expression profiling, we discovered a specific role for LRPPRC in the expression of all mitochondrial DNA (mtDNA)-encoded mRNAs, but not the rRNAs, without affecting nuclear genes encoding mitochondrial proteins. We designed seven shRNAs targeting the LRPPRC cDNA sequence to silence its expression in MCH58 immortalized human fibroblasts. The LRPPRC expression level in these cells ranged from 9% to 100%. We demonstrated that knockdown cells carried stable silencing of the target gene and associated biochemical phenotypes. Our goal was to engineer stable knockdown cells which recapitulate the LSFC disease phenotype and subject them to expression profiling using Affymetric microarrays to identify genesets and biochemical pathways that are altered.
2010-03-23 | E-GEOD-20847 | biostudies-arrayexpress
Project description:Introduction. Hindered by a limited understanding of the molecular mechanisms responsible for diabetic gastroenteropathy (DGE), patients are managed by symptom-based therapies. We investigated the duodenal mucosal expression of protein-coding genes and miRNAs in DGE and related these abnormalities to clinical features. Methods. mRNA and micro RNA (miRNA) expression and ultrastructure of duodenal mucosal biopsies were investigated in 39 DGE patients and 21 healthy controls. Results were analyzed in the context of diabetic phenotype and gastric emptying. Results. There were 3175 differentially-expressed genes (FDR<0.05), especially mitochondrial genes, in DGE versus controls. Several mitochondrial (mt) DNA-encoded genes (12 of 13 protein coding genes mainly involved in oxidative phosphorylation (OXPHOS), both rRNAs and 9 of 22 tRNAs) were downregulated; conversely, nuclear (n) DNA-encoded mitochondrial genes (eg, OXPHOS, TCA cycle) were upregulated in DGE. Motif analysis uncovered binding sites for transcription factors NRF1, GABPA and YY1, which regulate mitochondrial biogenesis, in the promoters of differentially expressed genes. Seventeen of 30 differentially expressed miRNAs in DGE targeted differentially expressed mitochondrial genes. Mitochondrial density was also reduced and correlated with the expression of 9 mt-DNA OXPHOS genes in DGE. Uncovered by a principal component (PC) analysis of OXPHOS genes, PC1 was significantly associated with neuropathy (P = 0.01) and with delayed gastric emptying (P < 0.05). Conclusion. In DGE, mtDNA- and nDNA-encoded mitochondrial genes are reduced and increased, respectively, associated with reduced mitochondrial density, neuropathy, and delayed gastric emptying, and correlated with cognate miRNA expression. Together, these findings provide substantial evidence for clinically-relevant mitochondrial disturbances in DGE.
2021-03-10 | GSE151496 | GEO