Cloning and expression of a mammalian peptide chain release factor with sequence similarity to tryptophanyl-tRNA synthetases.
AUTOR(ES)
Lee, C C
RESUMO
The termination of protein synthesis is encoded by in-frame nonsense (stop) codons. Most organisms use three nonsense codons: UGA, UAG, and UAA. In contrast to sense codons, which are decoded by specific tRNAs, nonsense codons are decoded by proteins called release factors (RFs). Here we report the cloning of a mammalian RF cDNA by the use of monoclonal antibodies specific for rabbit RF. Functional studies showed that, when expressed in Escherichia coli, the protein encoded by this cDNA has in vitro biochemical characteristics similar to those of previously characterized mammalian RFs. DNA sequencing of this eukaryotic RF cDNA revealed a remarkable sequence similarity to bacterial and mitochondrial tryptophanyl-tRNA synthetases, with the greatest similarity confined to the synthetase active site, and no obvious similarity to bacterial RFs.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=53930Documentos Relacionados
- Mammalian polypeptide chain release factor and tryptophanyl-tRNA synthetase are distinct proteins.
- The "eRF" clone corresponds to tryptophanyl-tRNA synthetase, not mammalian release factor.
- Effects of Trypanosoma brucei tryptophanyl-tRNA synthetases silencing by RNA interference
- Regulation of tryptophanyl-tRNA synthetase formation.
- Human interferon gamma potently induces the synthesis of a 55-kDa protein (gamma 2) highly homologous to rabbit peptide chain release factor and bovine tryptophanyl-tRNA synthetase.