Functional specificity among Hsp70 molecular chaperones

Science

Volumn 275, Issue 5298, 1997, Pages 387-389

  James, Philip ^a   Pfund, Christine ^a   Craig, Elizabeth A ^a  

^a UNIVERSITY OF WISCONSIN SCHOOL OF MEDICINE AND PUBLIC HEALTH   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

CHAPERONE; HEAT SHOCK PROTEIN 70; HYGROMYCIN B; POLYPEPTIDE;

AMINO ACID SEQUENCE; ARTICLE; NONHUMAN; PEPTIDE ANALYSIS; PHENOTYPE; PRIORITY JOURNAL; PROTEIN BINDING; PROTEIN FOLDING; SACCHAROMYCES CEREVISIAE;

ADENOSINE TRIPHOSPHATASES; COLD; FUNGAL PROTEINS; HSP70 HEAT-SHOCK PROTEINS; HYGROMYCIN B; PEPTIDES; PHENOTYPE; POLYRIBOSOMES; PROTEIN BINDING; RECOMBINANT FUSION PROTEINS; SACCHAROMYCES CEREVISIAE; SACCHAROMYCES CEREVISIAE PROTEINS;

EID: 0031016469     PISSN: 00368075     EISSN: None     Source Type: Journal    
DOI: 10.1126/science.275.5298.387     Document Type: Article

References (32)

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18. Ssa proteins function in protein translocation into organelles and regulation of the heat shook response (2). Ssb1 and Ssb2 are 99% identical and are associated with translating ribosomes (17); Δssb1 Δssb2 cells are sensitive to cold and to certain translation-inhibiting drugs such as hygromycin B. Reduced numbers of polysomes, previously reported in Δssb1 Δssb2 cells (17), are a general characteristic of slowly growing cells (24). Ssa and Ssb proteins are each unable to rescue the phenotypes of the other, even when Ssa1 is expressed from the SSB1 promoter, or vice versa (2).
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31. Polysomes were prepared and fractionated as described (17) from the Δssb1 Δssb2 strain JN208, except that gene fusions were present on centromeric plasmids and cells were grown in complete synthetic media minus uracil (SC - ura media) to an optical density of 1.0 at 600 nm. Gradient fractions were immunoblotted with a mixture of two antibodies to the COOH-termini of Ssa1 and Ssb1.
32. We thank R. Aramayo, J. Dahlberg, C. Fox, P. Kiley, and M. Krebs for helpful discussions. Supported by grants from NIH (E.A.C. and C.P.) and the Jane Coffin Childs Fund (P.J.).