Regulatory regions in the yeast FBP1 and PCK1 genes.

By deletion analysis of the fusion genes FBP1-lacZ and PCK1-lacZ we have identified a number of strong regulatory regions in the genes FBP1 and PCK1 which encode fructose-1,6-bisphosphatase and phosphoenolpyruvate carboxykinase. Lack of expression of beta-galactosidase in fusions lacking sequences from the coding regions suggests the existence of downstream activating elements. Both promoters have several UAS and URS regions as well as sites implicated in catabolite repression. We have found in both genes consensus sequences for the binding of the same regulatory proteins, such as yAP1, MIG1 or the complex HAP2/HAP3/HAP4. Neither deletion nor overexpression of the MIG1 gene affected the regulated expression of the FBP1 or PCK1 genes.