title: Duplication ofDrosophila melanogastermitochondrial EF-Tu: pre-adaptation to T-arm truncation and exclusion of bulky aminoacyl residues.
abstract: Translation elongation factor Tu (EF-Tu) delivers aminoacyl-tRNA (aa-tRNA) to ribosomes in protein synthesis. EF-Tu generally recognizes aminoacyl moieties and acceptor- and T-stems of aa-tRNAs. However, nematode mitochondrial (mt) tRNAs frequently lack all or part of the T-arm that is recognized by canonical EF-Tu. We previously reported that two distinct EF-Tu species, EF-Tu1 and EF-Tu2, respectively, recognize mt tRNAs lacking T-arms and D-arms in the mitochondria of the chromadorean nematodeCaenorhabditis elegansC. elegansEF-Tu2 specifically recognizes the seryl moiety of serylated D-armless tRNAs. Mitochondria of the enoplean nematodeTrichinellapossess three structural types of tRNAs: T-armless tRNAs, D-armless tRNAs, and cloverleaf tRNAs with a short T-arm.Trichinellamt EF-Tu1 binds to all three types and EF-Tu2 binds only to D-armless Ser-tRNAs, showing an evolutionary intermediate state from canonical EF-Tu to chromadorean nematode (e.g.C. elegans) EF-Tu species. We report here that two EF-Tu species also participate inDrosophila melanogastermitochondria. BothD. melanogasterEF-Tu1 and EF-Tu2 bound to cloverleaf and D-armless tRNAs.D. melanogasterEF-Tu1 has the ability to recognize T-armless tRNAs that do not evidently exist inD. melanogastermitochondria, but do exist in related arthropod species. In addition,D. melanogasterEF-Tu2 preferentially bound to aa-tRNAs carrying small amino acids, but not to aa-tRNAs carrying bulky amino acids. These results suggest that theDrosophilamt translation system could be another intermediate state between the canonical and nematode mitochondria-type translation systems.
authors.affiliation: Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562, Japan.|Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors.forename: Aya
authors.initials: A
authors.lastname: Sato
authors.affiliation: Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Takuma
authors.initials: T
authors.lastname: Suematsu
authors.affiliation: Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Koh-Ki
authors.initials: KK
authors.lastname: Aihara
authors.affiliation: Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Kita
authors.affiliation: Department of Chemistry and Biotechnology, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Suzuki
authors.affiliation: Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562, Japan.
authors.forename: Kimitsuna
authors.initials: K
authors.lastname: Watanabe
authors.affiliation: Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8562, Japan ywatanab@m.u-tokyo.ac.jp ohtsuk@okayama-u.ac.jp.
authors.forename: Takashi
authors.initials: T
authors.lastname: Ohtsuki
authors.affiliation: Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan ywatanab@m.u-tokyo.ac.jp ohtsuk@okayama-u.ac.jp.
authors.forename: Yoh-Ichi
authors.initials: YI
authors.lastname: Watanabe
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D005075:Biological Evolution; D017173:Caenorhabditis elegans / Q000235:genetics / Q000378:metabolism; D003001:Cloning, Molecular; D029721:Drosophila Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D004331:Drosophila melanogaster / Q000235:genetics* / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation; D007700:Kinetics; D008928:Mitochondria / Q000235:genetics / Q000378:metabolism; D024101:Mitochondrial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D009690:Nucleic Acid Conformation; D010444:Peptide Elongation Factor Tu / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D014176:Protein Biosynthesis; D020033:Protein Isoforms / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012346:RNA, Transfer, Amino Acyl / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity; D014234:Trichinella / Q000235:genetics / Q000378:metabolism
chemical_list: D029721:Drosophila Proteins; D024101:Mitochondrial Proteins; D020033:Protein Isoforms; D012346:RNA, Transfer, Amino Acyl; D011994:Recombinant Proteins; D010444:Peptide Elongation Factor Tu
keywords: Drosophila melanogaster; EF-Tu; mitochondria; tRNA