Affiliation:
1. Howard Hughes Medical Institute, Chicago, Illinois.
Abstract
The phenotypes of single Hsp104 and Hsp70 mutants of the budding yeast Saccharomyces cerevisiae provide no clue that these proteins are functionally related. Mutation of the HSP104 gene severely reduces the ability of cells to survive short exposures to extreme temperatures (thermotolerance) but has no effect on growth rates. On the other hand, mutations in the genes that encode Hsp70 proteins have significant effects on growth rates but do not reduce thermotolerance. The absence of a thermotolerance defect in S. cerevisiae Hsp70 mutants is puzzling, since the protein clearly plays an important role in thermotolerance in a variety of other organisms. In this report, examination of the phenotypes of combined Hsp104 and Hsp70 mutants uncovers similarities in the functions of Hsp104 and Hsp70 not previously apparent. In the absence of the Hsp104 protein, Hsp70 is very important for thermotolerance in S. cerevisiae, particularly at very early times after a temperature upshift. Similarly, Hsp104 plays a substantial role in vegetative growth under conditions of decreased Hsp70 protein levels. These results suggest a close functional relationship between Hsp104 and Hsp70.
Publisher
American Society for Microbiology
Subject
Molecular Biology,Microbiology
Reference43 articles.
1. Essential roles of 70 kDa heat inducible proteins;Craig E. A.;Bioessays,1989
2. Craig E. A. 1990. Regulation and function of the HSP70 multigene family of Saccharomyces cerevisiae p. 301-321. In R. I. Morimoto A. Tissieres and C. Georgopoulos (ed.) Stress proteins in biology and medicine. Cold Spring Harbor Laboratory Press Cold Spring Harbor N.Y.
3. Mutations of the heat inducible 70 kilodalton genes of yeast confer temperature sensitive growth;Craig E. A.;Cell,1984
4. Mutations in cognate genes of Saccharomyces cerevisiae hsp 7o result in reduced growth rates at low temperatures;Craig E. A.;Mol. Cell. Biol.,1985
5. Quality control and technical outcome of two-dimensional electrophoresis in a clinical laboratory setting;Daufeldt J. A.;Clin. Chem.,1984
Cited by
111 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献