DELETION ANALYSIS OF THE SUP2 GENE OF THE YEAST SACCHAROMYCES-CEREVISIAE

We report genetic studies on the function of different regions of the protein encoded by the SUP2 gene of Saccharomyces cerevisiae. The Sup2 protein consists of a C-terminal region homologous to the EF-1-alpha translation elongation factor, and a unique N-terminal region. The functions of different regions of the SUP2 gene were studied by removing regions from the gene without altering the reading frame. These constructs were maintained in yeasts on episomal or centromeric plasmids. The region homologous of EF-1-alpha is required for viability, while the remaining N-terminal region is not essential. The first 154 amino acids are required for the suppressor effect resulting from amplification of the SUP2 gene, and is itself adequate for this effect.