title: Aim-less translation: loss of Saccharomyces cerevisiae mitochondrial translation initiation factor mIF3/Aim23 leads to unbalanced protein synthesis.
abstract: The mitochondrial genome almost exclusively encodes a handful of transmembrane constituents of the oxidative phosphorylation (OXPHOS) system. Coordinated expression of these genes ensures the correct stoichiometry of the system's components. Translation initiation in mitochondria is assisted by two general initiation factors mIF2 and mIF3, orthologues of which in bacteria are indispensible for protein synthesis and viability. mIF3 was thought to be absent in Saccharomyces cerevisiae until we recently identified mitochondrial protein Aim23 as the missing orthologue. Here we show that, surprisingly, loss of mIF3/Aim23 in S. cerevisiae does not indiscriminately abrogate mitochondrial translation but rather causes an imbalance in protein production: the rate of synthesis of the Atp9 subunit of F1F0 ATP synthase (complex V) is increased, while expression of Cox1, Cox2 and Cox3 subunits of cytochrome c oxidase (complex IV) is repressed. Our results provide one more example of deviation of mitochondrial translation from its bacterial origins.
authors.affiliation: University of Tartu, Institute of Technology, Nooruse 1, 50411 Tartu, Estonia.|Molecular Biology Department, Faculty of Biology, M.V. Lomonosov Moscow State University, 1/12 Leninskie Gory, 119991 Moscow, Russia.
authors.forename: Anton
authors.initials: A
authors.lastname: Kuzmenko
authors.affiliation: Molecular Biology Department, Faculty of Biology, M.V. Lomonosov Moscow State University, 1/12 Leninskie Gory, 119991 Moscow, Russia.
authors.forename: Ksenia
authors.initials: K
authors.lastname: Derbikova
authors.affiliation: Department of Biochemistry and Biophysics, Center for Biomembrane Research, Stockholm University, SE-106 91 Stockholm, Sweden.
authors.forename: Roger
authors.initials: R
authors.lastname: Salvatori
authors.affiliation: University of Tartu, Institute of Technology, Nooruse 1, 50411 Tartu, Estonia.
authors.forename: Stoyan
authors.initials: S
authors.lastname: Tankov
authors.affiliation: University of Tartu, Institute of Technology, Nooruse 1, 50411 Tartu, Estonia.|Department of Molecular Biology, Umeå University, Building 6K, 6L University Hospital Area, SE-901 87 Umeå, Sweden.|Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Building 6K and 6L, University Hospital Area, SE-901 87 Umeå, Sweden.
authors.forename: Gemma C
authors.initials: GC
authors.lastname: Atkinson
authors.affiliation: University of Tartu, Institute of Technology, Nooruse 1, 50411 Tartu, Estonia.
authors.forename: Tanel
authors.initials: T
authors.lastname: Tenson
authors.affiliation: Department of Biochemistry and Biophysics, Center for Biomembrane Research, Stockholm University, SE-106 91 Stockholm, Sweden.
authors.forename: Martin
authors.initials: M
authors.lastname: Ott
authors.affiliation: Molecular Biology Department, Faculty of Biology, M.V. Lomonosov Moscow State University, 1/12 Leninskie Gory, 119991 Moscow, Russia.
authors.forename: Piotr
authors.initials: P
authors.lastname: Kamenski
authors.affiliation: University of Tartu, Institute of Technology, Nooruse 1, 50411 Tartu, Estonia.|Department of Molecular Biology, Umeå University, Building 6K, 6L University Hospital Area, SE-901 87 Umeå, Sweden.|Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Building 6K and 6L, University Hospital Area, SE-901 87 Umeå, Sweden.
authors.forename: Vasili
authors.initials: V
authors.lastname: Hauryliuk
mesh_terms: D002244:Carbon / Q000378:metabolism; D019069:Cell Respiration; D004272:DNA, Mitochondrial / Q000235:genetics / Q000378:metabolism; D039642:Eukaryotic Initiation Factors / Q000235:genetics* / Q000378:metabolism*; D008928:Mitochondria / Q000235:genetics* / Q000378:metabolism*; D000069396:Mitochondrial Ribosomes / Q000378:metabolism; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism*; D017384:Sequence Deletion
chemical_list: D004272:DNA, Mitochondrial; D039642:Eukaryotic Initiation Factors; D012333:RNA, Messenger; D002244:Carbon