Molecular basis of nutrient-controlled gene expression in Saccharomyces cerevisiae

The ability of a unicellular organism to alter patterns of gene expression in response to nutrient availability is essential to its survival in a changing environment. How is the cell able to identify individual metabolites amongst a myriad of other similar molecules, and convert the information of its presence into a concerted change in the transcription of the genes required for the response to that metabolite? There is increasing evidence that the activity of transcription factors can be influenced directly by interaction with metabolites. A variety of mechanisms have been identified by which this type of gene regulation by small molecules can occur.