Transcriptional responses of Saccharomyces cerevisiae to carbon and nitrogen deprivation
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ABSTRACT:
ORGANISM(S): Saccharomyces cerevisiae
PROVIDER: GSE11754 | GEO | 2009/02/02
SECONDARY ACCESSION(S): PRJNA106045
REPOSITORIES: GEO
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Project description:Metabolite concentrations can regulate gene expression, which can in turn regulate metabolic activity. The extent to which functionally related transcripts and metabolites show similar patterns of concentration changes, however, remains unestablished. We have therefore measured and analyzed the metabolomic (previously published in Brauer et al., PMID 17159141) and transcriptional responses (presented here) of Saccharomyces cerevisiae to carbon and nitrogen starvation. The transcriptomes of filter cultures of FY4 (a prototrophic, Mata derivative of S288C presented by Winston et al., PMID 7762301) were sampled during exponential growth in minimal media and at 10, 30, 60, 120, 240, and 480 minutes following a switch to media lacking ammonium (nitrogen starvation) or D-glucose (carbon starvation). Transcriptional profiles were measured using an Agilent Yeast Oligo Microarray (V2), with the zero timepoint (i.e. exponential growth) as the reference sample. This yielded 2 time-courses of 6 time-points each. Further information is available in the accompanying manuscript.
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Project description:Microorganisms are exposed to large variations in nutrient availability in nature. To cope with these variations and sustain growth, they maximize the utility of the available nutrients and adapt to nutritional deficiencies. We studied the transcriptional and metabolic dynamics in Saccharomyces cerevisiae in response to a gradual transition from glucose-limited growth to ammonia-limited growth under aerobic or anaerobic conditions. Through exposing yeast to a gradual increase in glucose availability, we discovered new aspects of regulation that ensured a balanced metabolism of glucose and ammonia to sustain growth. This required tight coordination of metabolism with different cellular processes. The coordinated expression of the genes involved in key cellular processes implicated the role of signaling pathways mediated by Tor1, Pka1 and Hog1. This is in contrast to the rapid increase in glucose availability, when Snf1 appeared to be the key regulator. The results presented here provide clear insight into key cellular processes that are affected by nutrient limitation and have direct implications in further studies on genome-scale regulation of metabolism.
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