AN ANTISUPPRESSOR THAT ACTS ON OMNIPOTENT SUPPRESSORS IN YEAST

Abstract
Six partially dominant antisuppressors were obtained that reduce the efficiency of two omnipotent yeast suppressors, sup45 and sup35, thought to be ribosomal ambiguity mutations. Each of these six antisuppressors was shown to fall within a single Mendelian locus, named asu9. The mu9 mutations are specific for omnipotent suppressors; they have no effect on several dominant tRNA-like suppressors. In the absence of suppressors, mu9 causes sensitivity to the aminoglycoside antibiotic, paromomycin. The properties of mu9 are consistent with the hypothesis that mu9 alters yeast ribosomal proteins.