Catalase activity is necessary for heat-shock recovery in Aspergillus nidulans germlings.
To understand the molecular mechanisms induced by stress that contribute to the development of tolerance in eukaryotic cells, the filamentous fungus Aspergillus nidulans has been chosen as a model system. Here, the response of A. nidulans germlings to heat shock is reported. The heat treatment dramatically increased the concentration of trehalose and induced the accumulation of mannitol and mRNA from the catalase gene catA. Both mannitol and catalase function to protect cells from different reactive oxygen species. Treatment with hydrogen peroxide increased A. nidulans germling viability after heat shock whilst mutants deficient in catalase were more sensitive to a 50 degrees C heat exposure. It is concluded that the defence against the lethal effects of heat exposure can be correlated with the activity of the defence system against oxidative stress.
Noventa-Jordão
Maria Antônia
MA
Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo and Universidade de Franca, Av. do Café S/N, CEP 14040-903, Ribeirão Preto, São Paulo, Brazil1.
Couto
Ricardo M
RM
Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo and Universidade de Franca, Av. do Café S/N, CEP 14040-903, Ribeirão Preto, São Paulo, Brazil1.
Goldman
Maria Helena S
MHS
Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil2.
Aguirre
Jesus
J
Instituto de Fisiologia Celular-UNAM, Mexico City, Mexico3.
Iyer
Suresh
S
Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID, USA4.
Caplan
Allan
A
Department of Microbiology, Molecular Biology, and Biochemistry, University of Idaho, Moscow, ID, USA4.
Terenzi
Hector F
HF
Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, São Paulo, Brazil2.
Goldman
Gustavo H
GH
Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo and Universidade de Franca, Av. do Café S/N, CEP 14040-903, Ribeirão Preto, São Paulo, Brazil1.
D001233:Aspergillus nidulans / Q000187:drug effects / Q000201:enzymology / Q000502:physiology*; D015152:Blotting, Northern; D002374:Catalase / Q000235:genetics / Q000378:metabolism*; D002849:Chromatography, Gas; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism*; D017353:Gene Deletion; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000494:pharmacology; D008353:Mannitol / Q000378:metabolism; D012331:RNA, Fungal / Q000032:analysis; D012333:RNA, Messenger / Q000032:analysis; D013997:Time Factors; D014199:Trehalose / Q000378:metabolism
D005656:Fungal Proteins; D006360:Heat-Shock Proteins; D012331:RNA, Fungal; D012333:RNA, Messenger; D008353:Mannitol; D014199:Trehalose; D006861:Hydrogen Peroxide; D002374:Catalase