Suppressor-specificity of antisuppressors in yeast

Abstract

SUMMARYEighteen mutations ofSaccharomyces cerevisiae, at eight loci, isolated as antisuppressors ofSUPQ2, an ochre-suppressing allele ofSUP11, were crossed with three other suppressors.They were found to abolish the ability ofSUP2(inserting tyrosine), to suppress the ochre mutationsade2.1andcan1.100, but not its ability, to suppresshis5.2orlys1.1.When coupled with any antisuppressor,SUPQ5, inserting serine, was also unable to suppressade2.1, but the suppression of other ochre mutations varied from oneasu-SUPQ5strain to another. No antisuppressor affected the ability ofSUP11-am, an amber-suppressing allele ofSUP11, to suppresstrp1.1, an amber mutation.