7 Regulation of the yeast general amino acid control pathway in response to nutrient stress

Abstract

In response to starvation for amino acids, yeast cells induce the expression of a collection of genes involved in amino acid metabolism. This pathway referred to as the general amino acid control is a true cross-pathway response that induces expression of genes contributing to the synthesis of all amino acids independent of which amino acid is limiting. In this review, we discuss the three basic parts of the general control pathway: 1) sensing of amino acid starvation by the protein kinase Gcn2p; 2) induction of the “master regulator” Gcn4p that involves a classic mechanism of translation control elicited by Gcn2p phosphorylation of eukaryotic initiation factor -2 (eIF2); and 3) the coordinate expression of stress remedy genes through Gcn4p-directed regulation of transcription. Recent studies suggest that Gcn4p can also interface with other stress response pathways, allowing the cell to direct the timing and content of stress gene expression in response to multiple stress inputs.