Methionine-mediated lethality in yeast cells at elevated temperature.
Saccharomyces cerevisiae cells grown at 30 degrees C in minimal medium containing methionine lose viability upon transfer to 45 degrees C, whereas cells grown in the absence of methionine survive. Cellular levels of two intermediates in the sulfate assimilation pathway, adenosine 5'-phosphosulfate (APS) and adenosine 5'-phosphosulfate 3'-phosphate, are increased by a posttranslational mechanism after sudden elevation of temperature in yeast cultures grown in the absence of methionine. Yeast cells unable to synthesize APS because of repression by methionine or mutation of the MET3 gene do not survive the temperature shift. Thus, methionine-mediated lethality at elevated temperature is linked to the inability to synthesize APS. The results demonstrate that APS plays an important role in thermotolerance.
Jakubowski
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H
Department of Microbiology and Molecular Genetics, University of Medicine and Dentistry of New Jersey-New Jersey Medical School, Newark 07103.
Goldman
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E
D000227:Adenine Nucleotides / Q000378:metabolism; D000250:Adenosine Phosphosulfate / Q000378:metabolism; D002453:Cell Cycle; D006360:Heat-Shock Proteins / Q000378:metabolism; D008715:Methionine / Q000378:metabolism*; D014176:Protein Biosynthesis; D011499:Protein Processing, Post-Translational; D012441:Saccharomyces cerevisiae / Q000254:growth & development*; D013696:Temperature
D000227:Adenine Nucleotides; D006360:Heat-Shock Proteins; D000250:Adenosine Phosphosulfate; D008715:Methionine