Yeast cells respond to the quantity and quality of
carbon and
nitrogen sources in the environment both by adjusting their
transcriptional and
metabolic profiles to make optimum use of the available
nutrients and by selecting a developmental program--budding, pseudohyphal differentiation, quiescence or sporulation--that maximizes their potential for survival under the existing
nutrient conditions. Recent studies fueled by genomic tools have refined our knowledge of the components and connections within individual pathways and the interconnections between pathways. More significantly, these studies begin to
paint an as yet inchoate portrait of the
yeast cells'
means of processing its environmental information, in which specific
transcription factors and
chromatin modifying activities coordinate input from several
signaling pathways to yield an appropriate and coherent response of genes involved in mass accumulation and
metabolism.
