Hsp104 responds to heat and oxidative stress with different intracellular localization in Saccharomyces cerevisiae.
TPN (tetrachloroisophthalonitrile) affected the growth in yeast Saccharomyces cerevisiae and enhanced the superoxide dismutase and glutathione reductase activity under sublethal concentration. Conversely, mild heat-shock treatment had no effect on the enzyme activities. These show they inhibit the metabolism diversely: TPN is an oxidative stressor and mild heat-shock treatment leads to thermogenesis. We have earlier reported that on exposure to TPN under sublethal concentration, heat-shock protein Hsp104 was induced in the same way as in the mild heat-shock treatment (Fujita et al., Biochem. Biophys. Res. Commun. (1995) 216, 1041-1047). However, intracellular localizations of Hsp104 showed different patterns in each treated cell according to immunoelectron microscopic observation. While Hsp104 was localized upon the circumference of the protein aggregates in mild heat-shocked cells, Hsp104 was distributed over the entire TPN-treated cells with no protein aggregates. These findings suggest Hsp104 adaptively responds to comprehensive stress and participates in an emergent rescue function as a molecular chaperone.
National Institute of Bioscience and Human-Technology, Agency of Industrial Science and Technology, Ibaraki, Japan. fjt@nibh.go.jp
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Fujita
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Kawai
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Iwahashi
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Komatsu
D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D005656:Fungal Proteins / Q000096:biosynthesis*; D005659:Fungicides, Industrial / Q000494:pharmacology; D005980:Glutathione Reductase / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000032:analysis / Q000096:biosynthesis*; D006358:Hot Temperature; D016253:Microscopy, Immunoelectron; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D009570:Nitriles / Q000494:pharmacology; D018384:Oxidative Stress; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000254:growth & development / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins; D013482:Superoxide Dismutase / Q000378:metabolism; D014617:Vacuoles / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure
D005656:Fungal Proteins; D005659:Fungicides, Industrial; D006360:Heat-Shock Proteins; D009570:Nitriles; D029701:Saccharomyces cerevisiae Proteins; C070972:HsP104 protein, S cerevisiae; D013482:Superoxide Dismutase; D005980:Glutathione Reductase; C005806:tetrachloroisophthalonitrile