Selection of genes repressed by cAMP that are induced by nutritional limitation in Saccharomyces cerevisiae

DNA-lacZ fusion libraries of yeast Saccharomyces cerevisiae were used to se lect genes coordinately regulated by the Ras-cAMP-cAPK signalling pathway. Sixteen new genes (AGP1, APE2, APE3, FPS1, GUT2, MDH2, PLB2, PYK2, RNR3, SU R1, UGA1, YHR033w, PBR006w, YHR143w, YMR086w and YOR173w) were found to be repressed by cAMP. Most of these genes encode for metabolic enzymes and are induced by nutritional limitations. These common properties suggest a role of this pathway in the metabolic adjustment of the cell to nutritional var iations. The induction of 10 of these genes is reduced in the msn2,msn4 dou ble mutant, which emphasizes the role of the Msn2/4p transcriptional activa tors in mediating the Ras-cAMP-cAPK signalling pathway. The Msn2p/ Msn4p-in dependent expression of the six other genes suggests the existence of other regulatory systems under the control of this pathway. Copyright (C) 1999 J ohn Wiley & Sons, Ltd.