Viable nonsense mutants for the essential gene SUP45 of Saccharomyces cerevisiae.

ABSTRACT:

Background

Termination of protein synthesis in eukaryotes involves at least two polypeptide release factors (eRFs) - eRF1 and eRF3. The highly conserved translation termination factor eRF1 in Saccharomyces cerevisiae is encoded by the essential gene SUP45.

Results

We have isolated five sup45-n (n from nonsense) mutations that cause nonsense substitutions in the following amino acid positions of eRF1: Y53 --> UAA, E266 --> UAA, L283 --> UAA, L317 --> UGA, E385 --> UAA. We found that full-length eRF1 protein is present in all mutants, although in decreased amounts. All mutations are situated in a weak termination context. All these sup45-n mutations are viable in different genetic backgrounds, however their viability increases after growth in the absence of wild-type allele. A

SUBMITTER: Moskalenko SE 

PROVIDER: S-EPMC150568 | biostudies-literature | 2003 Feb

REPOSITORIES: biostudies-literature