Release of extraction-resistant mRNA in stationary phase Saccharomyces cerevisiae produces a massive increase in transcript abundance in response to stress.

摘要: Background: As carbon sources are exhausted, Saccharomyces cerevisiae cells exhibit reduced metabolic activity and cultures enter the stationary phase. We asked whether in phase respond to additional stress at level of transcript abundance. Results: Microarrays were used quantify changes abundance from response stress. More than 800 mRNAs increased by one minute after oxidative A significant number these encode proteins involved responses. tested mRNA increases due new transcription, rapid poly-adenylation message (which would not be detected microarrays), or potential release mature present cell but resistant extraction during RNA isolation. Examination an polymerase II mutant, rpb1-1, suggested that transcription was required. Quantitative RT-PCR analysis a subset transcripts further isolated total polyadenylated. In contrast, over 2,000 protease treatment cellfree lysates exponentially growing cultures. Different subsets released temperature upshift, suggesting is stress-specific. Conclusions: Cells contain large extraction-resistant protease-labile, rapidly releasable form. The appears stressspecific. hypothesize associated with P-bodies.