Functional analysis of upstream activating elements in the promoter of the FBP1 gene from Saccharomyces cerevisiae

We have investigated the effect of different carbon sources and of different mutations on the capacity of two elements, UAS1 and UAS2, from the promoter of the FBP1 gene to form specific DNA-protein complexes and to activate expression of a reporter gene. The complexes are observed with nuclear extracts from yeast derepressed on glycerol or ethanol. When hxk2 mutants are grown on glucose the nuclear extracts are able to complex UAS1 but not UAS2, while for wild-type cells grown on galactose only the complex with UAS2 is formed. In contrast, in vivo the operation of both UASs is high in ethanol, moderate to low in glycerol, and negligible in galactose; no expression is observed in glucose even in a hxk2 background. There is no effect of a MIG1 deletion, either in the formation of DNA-protein complexes or on the expression of reporter genes.This work was supported by Grant PB94-0091-CO2-01 from the Dirección General de Investigación Científica y Técnica. J. F. M. was on leave of absence from Departamento de Bioquímica, I. Q., UFRJ 20249-900- Rio de Janeiro-Brazil and the recipient of a fellowship from Conselho Nacional de Desenvolvimento Cientifico e Tecnologico-CNPq-Brazil. O. Z. had a fellowship from the Spanish Plan de Formación de Personal Investigador