Premium
Translation ability of mitochondrial tRNAs Ser with unusual secondary structures in an in vitro translation system of bovine mitochondria
Author(s) -
Hanada Takao,
Suzuki Tsutomu,
Yokogawa Takashi,
TakemotoHori Chie,
Sprinzl Mathias,
Watanabe Kimitsuna
Publication year - 2001
Publication title -
genes to cells
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.912
H-Index - 115
eISSN - 1365-2443
pISSN - 1356-9597
DOI - 10.1046/j.1365-2443.2001.00491.x
Subject(s) - biology , translation (biology) , ribosome , transfer rna , stop codon , start codon , mitochondrion , protein biosynthesis , genetics , biochemistry , rna , messenger rna , amino acid , gene
Background Metazoan mitochondrial (mt) tRNAs are structurally quite different from the canonical cloverleaf secondary structure. The mammalian mt tRNA Ser GCU for AGY codons (Y = C or U) lacks the entire D arm, whereas tRNA Ser UGA for UCN codons (N = A, G, C or U) has an extended anti‐codon stem. It has been a long‐standing problem to prove experimentally how these tRNAs Ser work in the mt translation system. Results To solve the above‐mentioned problem, we examined their translational abilities in an in vitro bovine mitochondrial translation system using transcripts of altered tRNA Ser analogues derived from bovine mitochondria. Both tRNA Ser analogues had almost the same ability to form ternary complexes with mt EF‐Tu and GTP. The D‐arm‐lacking tRNA Ser GCU analogue had considerably lower translational activity than the tRNA Ser UGA analogue and produced mostly short oligopeptides, up to a tetramer. In addition, tRNA Ser GCU analogue was disfavoured by the ribosome when other tRNAs capable of decoding the cognate codon were available. Conclusion Both mt tRNA Ser GCU and tRNA Ser UGA analogues with unusual secondary structure were found to be capable of translation on the ribosome. However, the tRNA Ser GCU analogue has some molecular disadvantage on the ribosome, which probably derives from the lack of a D arm.