Open AccessUsage of the three tennination codons in a single eukaryotic cell, the Xenopus laevis oocyte
Author(s) -
Mariann Bienz,
Eric Kubli,
Jürg Kohli,
S. deHenau,
Georges Huez,
Gérard Marbaix,
Henri Grosjean
Publication year - 1981
Publication title -
nucleic acids research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 9.008
H-Index - 537
eISSN - 1362-4954
pISSN - 0305-1048
DOI - 10.1093/nar/9.15.3835
Subject(s) - biology , xenopus , oocyte , salientia , microbiology and biotechnology , genetics , evolutionary biology , gene , embryo
Oocytes from Xenopus laevis were injected with purified amber (UAG), ochre (UAA), and opal (UGA) suppressor tRNAs from yeasts. The radioactively labeled proteins translated from the endogenous mRNAs were then separated on two-dimensional gels. All three termination codons are used in a single cell, the Xenopus laevis oocyte. But a surprisingly low number of readthrough polypeptides were observed from the 600 mRNAs studied in comparison to uninjected oocytes. The experimental data are compared with the conclusions obtained from the compilation of all available termination sequences on eukaryotic and prokaryotic mRNAs. This comparison indicates that the apparent resistance of natural termination codons against readthrough, as observed by the microinjection experiments, cannot be explained by tandem or very close second stop codons. Instead it suggests that specific context sequences around the termination codons may play a role in the efficiency of translation termination.