Translational readthrough of a termination codon in the yeast mitochondrial mRNA VAR1 as a result of mutation in the release factor mRF1.

نویسندگان

  • Maurice L Claisse
  • Magdalena Boguta
  • Włodzimierz Zagórski
چکیده

Yeast mitochondrial DNA codes for eight major polypeptides. Translation of he mitochondrially encoded polypeptides in strains with mutated mitochondrial release factor, mRF1, was found to result in the synthesis of a novel protein, V2. Different mrf1 alleles were associated with different efficiency of V2p synthesis. Translation of V2p was enhanced by paromomycin. Comparative analysis of peptides resulting from protease digestion indicated that V2p is a derivative of Var1p. According to our hypothesis, V2p represents a readthrough product of the natural stop codon in VAR1 mRNA.

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عنوان ژورنال:
  • Acta biochimica Polonica

دوره 52 1  شماره 

صفحات  -

تاریخ انتشار 2005