The heat shock response in yeast: differential regulations and contributions of the Msn2p/Msn4p and Hsf1p regulons.
The heat shock transcription factor Hsf1p and the stress-responsive transcription factors Msn2p and Msn4p are activated by heat shock in the yeast Saccharomyces cerevisiae. Their respective contributions to heat shock protein induction have been analysed by comparison of mutants and wild-type strains using [35S]-methionine labelling and two-dimensional gel electrophoresis. Among 52 proteins induced by a shift from 25 degrees C to 38 degrees C, half of them were found to be dependent upon Msn2p and/or Msn4p (including mostly antioxidants and enzymes involved in carbon metabolism), while the other half (including mostly chaperones and associated proteins) were dependent upon Hsf1p. The two sets of proteins overlapped only slightly. Three proteins were induced independently of these transcription factors, suggesting the involvement of other transcription factor(s). The Ras/cAMP/PKA signalling pathway cAMP had a negative effect on the induction of the Msn2p/Msn4p regulon, but did not affect the Hsf1p regulon. Thus, the two types of transcription factor are regulated differently and control two sets of functionally distinct proteins, suggesting two different physiological roles in the heat shock cellular response.
Laboratoire Information Génétique et Développement, Institut de Génétique et Microbiologie, UMR C8621, Université Paris-Sud, Bâtiment 400, 91405 Orsay Cedex, France. boy@igmors.u-psud.fr
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E
Boy-Marcotte
G
G
Lagniel
M
M
Perrot
F
F
Bussereau
A
A
Boudsocq
M
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Jacquet
J
J
Labarre
D000242:Cyclic AMP / Q000378:metabolism; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics*; D015180:Electrophoresis, Gel, Two-Dimensional; D006360:Heat-Shock Proteins / Q000235:genetics*; D006358:Hot Temperature; D008715:Methionine / Q000378:metabolism; D018085:Regulon; D012441:Saccharomyces cerevisiae / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors / Q000235:genetics*; D018631:ras Proteins / Q000378:metabolism
D004268:DNA-Binding Proteins; C067168:HSF1 protein, S cerevisiae; D006360:Heat-Shock Proteins; C081935:MSN2 protein, S cerevisiae; C081937:MSN4 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D008715:Methionine; D000242:Cyclic AMP; D017868:Cyclic AMP-Dependent Protein Kinases; D018631:ras Proteins