The GAL11 gene encodes an auxiliary transcription factor required for full expression of many, if not all, genes of the yeast Saccharomycescerevisiae. We have recently shown that GAL11/-encoded protein (GAL111p) enhances basal transcription from the CYC1 promoter in a cell-free transcription system [(1993) Proc. Natl. Acad. Sci. USA 90, 8382-8386]. Here we indicate that Ga111p stimulates basal transcription in a gene-specific manner in vitro. We further suggest that the mechanism underlying the transcriptional stimulation by Ga111p is distinct from that by DNA-bound activators, since Ga111p stimulated transcription in a reaction system where activators were unable to enhance transcription due to the lack of intermediary factors.
