- Japan Society for Bioscience, Biotechnology, and Agrochemistry
- Bioscience, biotechnology, and biochemistry (ISSN:09168451)
- vol.75, no.2, pp.323-330, 2011-02-23
The <I>Saccharomyces cerevisiae</I> gene <I>GTS1</I> is pleiotropic. <I>GTS1</I> induction produces a variety of biological phenomena represented by heat tolerance. To clarify the interaction partners of Gts1p, tandem affinity purification and immunoprecipitation were performed. Ssa1p and Ssa2p, members of the 70-kDa heat-shock protein family, were identified. Co-expression of <I>SSA1</I> or <I>SSA2</I> inhibited Gts1p nuclear import. As compared to the wild type, the <I>SSA1</I> and <I>SSA2</I> double-deletion mutant showed enhancement of Gts1p-mediated heat tolerance in the stationary phase, although neither of the single deletions affected heat tolerance, irrespective of <I>GTS1</I> induction. These results indicate that the heat tolerance function of Gts1p is regulated by Ssa1p and Ssa2p. Furthermore, time-dependent production of Ssa1p and Ssa2p revealed that Gts1p controls the production of Ssa1p and Ssa2p, and that the total amounts of Ssa1p and Ssa2p are important in inhibiting the unique function of Gts1p.