Identification of an upstream activation site in the pyruvate decarboxylase structural gene (PDC1) of Saccharomyces cerevisiae

Summary The upstream region of the Saccharomyces cerevisiae pyruvate decarboxylase structural gene, PDC1, has been isolated and fused to the indicator gene Escherichia coli lacZ. 1.2 kb of the upstream region has been sequenced. The PDC1-lacZ fusion has been integrated at the ura3-52 locus in the yeast genome, and has a basal level of expression on ethanol. On glucose media this level is increased 30–50 fold. An upstream activation site, UAS_pdc, between 793 and 535 by upstream from the ATG of PDC1, which mediates the response to glucose has been identified by deletion analysis. The UAS_pdc contains a consensus RPG box, originally identified in ribosomal protein genes (Leer et al. 1985). The function of UAS_pdc is independent of distance from the ATG. There is also an upstream repressing sequence located between 535 and 385 by upstream from the translational start of PDC1.