Interactions between chromosomal omnipotent suppressors and extrachromosomal effectors in Saccharomyces cerevisiae

Chromosomal omnipotent suppressor mutations recovered in ψ strains of Saccharomyces cerevisiae were brought into ψ cytoplasm. SUP46, SUP138 and SUP139 acted as dominant omnipotent suppressors in the ψ cytoplasm though their suppressor activity was substantially reduced. SUP46 and SUP138 conferred recessive thermosensitivity and antibiotic sensitivity in ψ cytoplasm as in ψ cytoplasm. On the other hand, sup111 through sup115, which acted as recessive omnipotent suppressors in the ψ cytoplasm, manifested no, or very low, suppressor activity in the ψ cytoplasm. They, however, still enhanced the efficiency of the SUP29 tRNA suppressor in ψ cytoplasm. A multicopy plasmid carrying the wild-type SUP35 gene enhanced the efficiency of sup111 in ψ cytoplasm. © 1991 Springer-Verlag.