title: Pleurotus sajor-caju HSP100 complements a thermotolerance defect in hsp104 mutant Saccharomyces cerevisiae.
abstract: A putative Hsp100 gene was cloned from the fungus Pleurotus sajor-caju. mRNA expression studies demonstrated that this gene (designated PsHsp100) is highly induced by high temperature,induced less strongly by exposure to ethanol, and not induced by drought or salinity. Heat shock induction is detectable at 37 degrees C and reaches a maximum level at 42 degrees C. PsHsp100 mRNA levels sharply increased within 15 min of exposure to high temperature, and reached a maximum expression level at 2 h that was maintained for several hours. These results indicate that PsHsp100 could work at an early step in thermotolerance. To examine its function, PsHsp100 was transformed into a temperature-sensitive hsp104 deletion mutant Saccharomycetes cerivisiae strain to test the hypothesis that PsHSP100 is an protein that functions in thermotolerance. Overexpression of PsHSP100 complemented the thermotolerance defect of the hsp104 mutant yeast, allowing them being survive even at 50 degree C for 4 h. These results indicate that PsHSP100 protein is functional as an HSP100 in yeast and could play and important role in thermotolerance in P. sajor-caju.
authors.affiliation: National Institute of Agricultural Biotechnology, Rural Development Administration, Suwon 441-707, Korea.
authors.forename: Jin-Ohk
authors.initials: JO
authors.lastname: Lee
authors.forename: Mi-Jeong
authors.initials: MJ
authors.lastname: Jeong
authors.forename: Tack-Ryun
authors.initials: TR
authors.lastname: Kwon
authors.forename: Seung-Kon
authors.initials: SK
authors.lastname: Lee
authors.forename: Myung-Ok
authors.initials: MO
authors.lastname: Byun
authors.forename: Ill-Min
authors.initials: IM
authors.lastname: Chung
authors.forename: Soo-Chul
authors.initials: SC
authors.lastname: Park
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D005656:Fungal Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D005786:Gene Expression Regulation; D005816:Genetic Complementation Test; D006360:Heat-Shock Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D008969:Molecular Sequence Data; D030781:Organisms, Genetically Modified; D010802:Phylogeny; D020076:Pleurotus / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D016415:Sequence Alignment
chemical_list: D005656:Fungal Proteins; D006360:Heat-Shock Proteins; D012333:RNA, Messenger; D029701:Saccharomyces cerevisiae Proteins; C070972:HsP104 protein, S cerevisiae