A CHICKEN BETA-ACTIN GENE CAN COMPLEMENT A DISRUPTION OF THE SACCHAROMYCES-CEREVISIAE ACT1 GENE

Recently it was demonstrated that beta-actin can be produced in Saccharomyces cerevisiae by using the expression plasmid pY-beta-actin (R. Karlsson, Gene 68:249-258, 1988), and several site-specific mutants are now being produced in a protein engineering study. To establish a system with which recombinant actin mutants can be tested in vivo and thus enable a correlation to be made with functional effects observed in vitro, a yeast strain lacking endogenous yeast actin and expressing beta-actin was constructed. This strain is viable but has an altered morphology and a slow-growth phenotype and is temperature sensitive to the point of lethality at 37-degrees-C.