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A potato mitochondrial isoleucine tRNA is coded for by a mitochondrial gene possessing a methionine anticodon.

ABSTRACT: The nucleotide sequence of a potato mitochondrial tRNA(Ile) has been determined. This tRNA has a lysidine-like minor nucleotide in the first position of the anticodon (position 34). The corresponding mitochondrial gene has been cloned and sequenced. This gene has a CAT anticodon which corresponds to methionine. The C residue in the anticodon must therefore be post-transcriptionally modified. The mature tRNA has isoleucine-accepting activity but no methionine-accepting activity. This is the first report showing that in plant mitochondria a post-transcriptional modification could change the amino-acid specificity of a tRNA, as compared to that of the corresponding gene.

SUBMITTER: Weber F

PROVIDER: S-EPMC332112 | biostudies-other | 1990 Sep

REPOSITORIES: biostudies-other

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A potato mitochondrial isoleucine tRNA is coded for by a mitochondrial gene possessing a methionine anticodon.

Weber F F Dietrich A A Weil J H JH Maréchal-Drouard L L

Nucleic acids research 19900901 17

The nucleotide sequence of a potato mitochondrial tRNA(Ile) has been determined. This tRNA has a lysidine-like minor nucleotide in the first position of the anticodon (position 34). The corresponding mitochondrial gene has been cloned and sequenced. This gene has a CAT anticodon which corresponds to methionine. The C residue in the anticodon must therefore be post-transcriptionally modified. The mature tRNA has isoleucine-accepting activity but no methionine-accepting activity. This is the first ...[more]

PMID: 1698276

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