title: Mitochondrial Polyadenylation Is a One-Step Process Required for mRNA Integrity and tRNA Maturation.
abstract: Polyadenylation has well characterised roles in RNA turnover and translation in a variety of biological systems. While polyadenylation on mitochondrial transcripts has been suggested to be a two-step process required to complete translational stop codons, its involvement in mitochondrial RNA turnover is less well understood. We studied knockdown and knockout models of the mitochondrial poly(A) polymerase (MTPAP) in Drosophila melanogaster and demonstrate that polyadenylation of mitochondrial mRNAs is exclusively performed by MTPAP. Further, our results show that mitochondrial polyadenylation does not regulate mRNA stability but protects the 3' terminal integrity, and that despite a lack of functioning 3' ends, these trimmed transcripts are translated, suggesting that polyadenylation is not required for mitochondrial translation. Additionally, loss of MTPAP leads to reduced steady-state levels and disturbed maturation of tRNACys, indicating that polyadenylation in mitochondria might be important for the stability and maturation of specific tRNAs.
authors.affiliation: Department of Mitochondrial Biology, Max Planck Institute for Biology of Ageing, Cologne, Germany.
authors.forename: Ana
authors.initials: A
authors.lastname: Bratic
authors.affiliation: Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Paula
authors.initials: P
authors.lastname: Clemente
authors.affiliation: Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Javier
authors.initials: J
authors.lastname: Calvo-Garrido
authors.affiliation: Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Camilla
authors.initials: C
authors.lastname: Maffezzini
authors.affiliation: Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Andrea
authors.initials: A
authors.lastname: Felser
authors.affiliation: Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.|Centre for Inherited Metabolic Diseases, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Rolf
authors.initials: R
authors.lastname: Wibom
authors.affiliation: Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.|Centre for Inherited Metabolic Diseases, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Anna
authors.initials: A
authors.lastname: Wedell
authors.affiliation: Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.|Centre for Inherited Metabolic Diseases, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Christoph
authors.identifier: 0000-0003-0418-1673
authors.initials: C
authors.lastname: Freyer
authors.affiliation: Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.|Centre for Inherited Metabolic Diseases, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Anna
authors.initials: A
authors.lastname: Wredenberg
mesh_terms: D000818:Animals; D018388:Codon, Terminator; D004331:Drosophila melanogaster / Q000235:genetics*; D055785:Gene Knockdown Techniques; D008928:Mitochondria / Q000235:genetics; D024101:Mitochondrial Proteins / Q000096:biosynthesis / Q000235:genetics; D026723:Polyadenylation / Q000235:genetics*; D014176:Protein Biosynthesis / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics*; D000077278:RNA, Mitochondrial; D012343:RNA, Transfer / Q000235:genetics
chemical_list: D018388:Codon, Terminator; D024101:Mitochondrial Proteins; D012333:RNA, Messenger; D000077278:RNA, Mitochondrial; C029305:mitochondrial messenger RNA; D012343:RNA, Transfer