Losing the stem-loop structure from metazoan mitochondrial trnas and co-evolution of interacting factors

Yoh ichi Watanabe, Takuma Suematsu, Takashi Ohtsuki

Research output: Contribution to journalArticle

28 Citations (Scopus)


Conventional tRNAs have highly conserved sequences, four-armed cloverleaf secondary structures, and L-shaped tertiary structures. However, metazoan mitochondrial tRNAs contain several exceptional structures. Almost all tRNAsSer for AGY/N codons lack the D-arm. Furthermore, in some nematodes, no four-armed cloverleaf-type tRNAs are present: two tRNAsSer without the D-arm and 20 tRNAs without the T-arm are found. Previously, we showed that in nematode mitochondria, an extra elongation factor Tu (EF-Tu) has evolved to support interaction with tRNAs lacking the T-arm, which interact with C-terminal domain 3 in conventional EF-Tu. Recent mitochondrial genome analyses have suggested that in metazoan lineages other than nematodes, tRNAs without the T-arm are present. Furthermore, even more simplified tRNAs are predicted in some lineages. In this review, we discuss mitochondrial tRNAs with divergent structures, as well as protein factors, including EF-Tu, that support the function of truncated metazoan mitochondrial tRNAs.

Original languageEnglish
Pages (from-to)1
Number of pages1
JournalFrontiers in Genetics
Issue numberMAY
Publication statusPublished - 2014



  • Aminoacyl-trna synthetase
  • D-arm
  • Elongation factor Tu
  • Mitochondrial trna
  • Ribosome
  • T-arm
  • Trna nucleotidyltransferase

ASJC Scopus subject areas

  • Genetics
  • Molecular Medicine
  • Genetics(clinical)

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