A Drosophila gene promoter is subject to glucose repression in yeast cells

Previous work has shown that the alpha-amylase gene of Drosophila melanogaster is subject to repression by dietary glucose. Moreover, glucose repression of this gene is mediated by promoter elements that lie upstream of the transcriptional start site. In this study, we examined the activity of the glucose-repressible Drosophila promoter in transformed yeast cells. We show that the amylase promoter region can mediate glucose repression of a heterologous reporter gene in yeast. The implication of this result is that the yeast regulatory machinery can recognize the Drosophila promoter signals. This, in turn, implies an unexpectedly high degree of evolutionary conservation in the mechanism of glucose repression among eukaryotes. It also shows that genes that have acquired complex patterns of developmental regulation-e.g., the Drosophila amylase gene, can still retain, intact, more primitive forms of regulation, such as glucose repression.