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Trm7p catalyses the formation of two 2'-O-methylriboses in yeast tRNA anticodon loop.

ABSTRACT: The genome of Saccharomyces cerevisiae encodes three close homologues of the Escherichia coli 2'-O-rRNA methyltransferase FtsJ/RrmJ, designated Trm7p, Spb1p and Mrm2p. We present evidence that Trm7p methylates the 2'-O-ribose of nucleotides at positions 32 and 34 of the tRNA anticodon loop, both in vivo and in vitro. In a trm7Delta strain, which is viable but grows slowly, translation is impaired, thus indicating that these tRNA modifications could be important for translation efficiency. We discuss the emergence of a family of three 2'-O-RNA methyltransferases in Eukaryota and one in Prokaryota from a common ancestor. We propose that each eukaryotic enzyme is located in a different cell compartment, in which it would methylate a different RNA that can adopt a very similar secondary structure.

SUBMITTER: Pintard L

PROVIDER: S-EPMC125368 | biostudies-literature | 2002 Apr

REPOSITORIES: biostudies-literature

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Trm7p catalyses the formation of two 2'-O-methylriboses in yeast tRNA anticodon loop.

Pintard Lionel L Lecointe François F Bujnicki Janusz M JM Bonnerot Claire C Grosjean Henri H Lapeyre Bruno B

The EMBO journal 20020401 7

The genome of Saccharomyces cerevisiae encodes three close homologues of the Escherichia coli 2'-O-rRNA methyltransferase FtsJ/RrmJ, designated Trm7p, Spb1p and Mrm2p. We present evidence that Trm7p methylates the 2'-O-ribose of nucleotides at positions 32 and 34 of the tRNA anticodon loop, both in vivo and in vitro. In a trm7Delta strain, which is viable but grows slowly, translation is impaired, thus indicating that these tRNA modifications could be important for translation efficiency. We dis ...[more]

PMID: 11927565

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