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

AUTOR(ES)

Pintard, Lionel

FONTE

Oxford University Press

RESUMO

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 trm7Δ 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.

Documentos Relacionados

• Identification of specific Rp-phosphate oxygens in the tRNA anticodon loop required for ribosomal P-site binding
• The bases of the tRNA anticodon loop are independent by genetic criteria.
• Single sequence of a helix-loop peptide confers functional anticodon recognition on two tRNA synthetases.
• Construction of a composite tRNA gene by anticodon loop transplant.
• The nucleotide in position 32 of the tRNA anticodon loop determines ability of anticodon UCC to discriminate among glycine codons.