1. The FASTK family proteins fine-tune mitochondrial RNA processing
- Author
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Ohkubo, Akira, Van Haute, Lindsey, Rudler, Danielle L, Stentenbach, Maike, Steiner, Florian A, Rackham, Oliver, Minczuk, Michal, Filipovska, Aleksandra, Martinou, Jean-Claude, Ohkubo, Akira [0000-0002-5441-8547], Rudler, Danielle L [0000-0002-5540-6548], Stentenbach, Maike [0000-0002-1933-9149], Steiner, Florian A [0000-0002-0514-5060], Minczuk, Michal [0000-0001-8242-1420], Filipovska, Aleksandra [0000-0002-6998-8403], Martinou, Jean-Claude [0000-0002-9847-2051], and Apollo - University of Cambridge Repository
- Subjects
RNA, Mitochondrial ,education ,Molecular Probe Techniques ,QH426-470 ,Bioenergetics ,Biochemistry ,Electrophoretic Blotting ,Cell Line ,Mitochondrial Proteins ,Electrophoretic Techniques ,Gene Knockout Techniques ,Genetics ,Humans ,RNA, Messenger ,RNA Processing, Post-Transcriptional ,Non-coding RNA ,Molecular Biology Techniques ,Molecular Biology ,Energy-Producing Organelles ,health care economics and organizations ,Gel Electrophoresis ,Biology and life sciences ,Messenger RNA ,RNA-Binding Proteins ,Cell Biology ,humanities ,Mitochondria ,Nucleic acids ,Research and analysis methods ,RNA processing ,Ribosomal RNA ,RNA ,Gene expression ,Cellular Structures and Organelles ,Transfer RNA ,Northern Blot ,Transcriptome ,Ribosomes ,Research Article - Abstract
Funder: The Cancer Council of Western Australia, Funder: UWA Postgraduate Scholarships, Transcription of the human mitochondrial genome and correct processing of the two long polycistronic transcripts are crucial for oxidative phosphorylation. According to the tRNA punctuation model, nucleolytic processing of these large precursor transcripts occurs mainly through the excision of the tRNAs that flank most rRNAs and mRNAs. However, some mRNAs are not punctuated by tRNAs, and it remains largely unknown how these non-canonical junctions are resolved. The FASTK family proteins are emerging as key players in non-canonical RNA processing. Here, we have generated human cell lines carrying single or combined knockouts of several FASTK family members to investigate their roles in non-canonical RNA processing. The most striking phenotypes were obtained with loss of FASTKD4 and FASTKD5 and with their combined double knockout. Comprehensive mitochondrial transcriptome analyses of these cell lines revealed a defect in processing at several canonical and non-canonical RNA junctions, accompanied by an increase in specific antisense transcripts. Loss of FASTKD5 led to the most severe phenotype with marked defects in mitochondrial translation of key components of the electron transport chain complexes and in oxidative phosphorylation. We reveal that the FASTK protein family members are crucial regulators of non-canonical junction and non-coding mitochondrial RNA processing.
- Published
- 2021