title: TEFM (c17orf42) is necessary for transcription of human mtDNA.
abstract: Here we show that c17orf42, hereafter TEFM (transcription elongation factor of mitochondria), makes a critical contribution to mitochondrial transcription. Inactivation of TEFM in cells by RNA interference results in respiratory incompetence owing to decreased levels of H- and L-strand promoter-distal mitochondrial transcripts. Affinity purification of TEFM from human mitochondria yielded a complex comprising mitochondrial transcripts, mitochondrial RNA polymerase (POLRMT), pentatricopeptide repeat domain 3 protein (PTCD3), and a putative DEAD-box RNA helicase, DHX30. After RNase treatment only POLRMT remained associated with TEFM, and in human cultured cells TEFM formed foci coincident with newly synthesized mitochondrial RNA. Based on deletion mutants, TEFM interacts with the catalytic region of POLRMT, and in vitro TEFM enhanced POLRMT processivity on ss- and dsDNA templates. TEFM contains two HhH motifs and a Ribonuclease H fold, similar to the nuclear transcription elongation regulator Spt6. These findings lead us to propose that TEFM is a mitochondrial transcription elongation factor.
authors.affiliation: MRC Mitochondrial Biology Unit, Wellcome Trust/MRC Building, Hills Road, Cambridge CB2 0XY, UK. michal.minczuk@mrc-mbu.cam.ac.uk
authors.forename: Michal
authors.initials: M
authors.lastname: Minczuk
authors.forename: Jiuya
authors.initials: J
authors.lastname: He
authors.forename: Anna M
authors.initials: AM
authors.lastname: Duch
authors.forename: Thijs J
authors.initials: TJ
authors.lastname: Ettema
authors.forename: Aleksander
authors.initials: A
authors.lastname: Chlebowski
authors.forename: Karol
authors.initials: K
authors.lastname: Dzionek
authors.forename: Leo G J
authors.initials: LG
authors.lastname: Nijtmans
authors.forename: Martijn A
authors.initials: MA
authors.lastname: Huynen
authors.forename: Ian J
authors.initials: IJ
authors.lastname: Holt
mesh_terms: D020134:Catalytic Domain; D002460:Cell Line; D004272:DNA, Mitochondrial / Q000032:analysis; D012321:DNA-Directed RNA Polymerases / Q000737:chemistry / Q000378:metabolism; D020868:Gene Silencing; D006801:Humans; D008928:Mitochondria / Q000235:genetics*; D024101:Mitochondrial Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000502:physiology*; D010085:Oxidative Phosphorylation; D017434:Protein Structure, Tertiary; D012313:RNA / Q000096:biosynthesis* / Q000378:metabolism; D000077278:RNA, Mitochondrial; D014157:Transcription Factors / Q000502:physiology*; D035602:Transcriptional Elongation Factors / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000502:physiology*
chemical_list: D004272:DNA, Mitochondrial; D024101:Mitochondrial Proteins; D000077278:RNA, Mitochondrial; C560090:TEFM protein, human; D014157:Transcription Factors; D035602:Transcriptional Elongation Factors; D012313:RNA; D012321:DNA-Directed RNA Polymerases; C519567:POLRMT protein, human