9 Springer-Verlag 1990 A sequence that directs transcriptional initiation in yeast

Summary. While RNA polymerase II of the yeast Saccha-romyces cerevisiae initiates transcription at discrete sites, these sites are located over a wide range of distances from the TATA box for different genes. This variability has led to a number of proposals for consensus sequences located at the initiation site which, in conjunction with the TATA box, would direct initiation. We tested this hypothesis via oligonucleotide-directed mutagenesis, by placing the se-quence CAAG, a member of one of these consensus e-quences, upstream of the coding sequence of the CYC7 gene at a site at which initiation does not occur. The distance between the TATA sequence and this putative initiation site was varied by inserting it into the wild-type gene and three deletion mutants. The results demonstrat-ed that this sequence can serve as an initiation site when located 49, 77, or 106 bp from the TATA sequence, but not when located 30 bp away. Key words: CYC7 gene Cytochrome c- TATA bo