Control of Translational Accuracy in Yeast: The Role of the Sal4 (Sup45) Protein

Abstract

It is clearly important for an organism to ensure that translational errors are kept to a minimum. The isolation of genetic modifiers of nonsense suppressors from both E. coli and yeast has provided a powerful genetic screen for mutants with defects in the control of translational accuracy (Eggertsson and Soll, 1988; Sherman, 1982). That such mutants are defective in the control of translational accuracy can be readily confirmed by demonstrating their hypersensitivity to antibiotics and other agents known to perturb translational accuracy. In E. coli this approach has uncovered a number of key components of the translational machinery important for maintaining the accuracy level; for example the ram (ribosomal ambiguity) mutants which increase translational misreading have demonstrated important roles for the ribosomal proteins S4 and S5 (Gorini, 1974; Cabezon et al, 1976). We are taking a similar approach in the yeast Saccharomyces cerevisiae in an attempt to uncover analogous translational components in this simple eukaryote.