The DNA-binding protein RAP1 is required for efficient transcriptional activation of the yeast PYK glycolytic gene.

We show by deletion mutagenesis, followed by in vivo and in vitro analysis, that the binding of a protein factor to the upstream activation sequence (UAS) of the Saccharomyces cerevisiae glycolytic gene PYK, encoding pyruvate kinase, is required for efficient transcription of the corresponding coding region. In addition, gel electrophoretic mobility shift and DNase I protection studies, involving yeast gene products expressed in E. coli, suggest that this trans-acting DNA-binding protein is encoding by the RAP1 gene. The identification of RAP1 binding sites located within the UAS element of the yeast PYK, PGK (phosphoglycerate kinase) and ENO1 (enolase) genes, and in the 5'-upstream region of the ADHI (alcohol dehydrogenase) gene, suggests that a mechanism of coordinate gene expression involving several of the glycolytic genes may exist in yeast.