Roles of SWI/SNF and HATs throughout the dynamic transcription of a yeast glucose-repressible gene.

Eucaryotic gene expression requires chromatin-remodeling activities. We show by time-course studies that transcriptional induction of the yeast glucose-regulated SUC2 gene is rapid and shows a striking biphasic pattern, the first phase of which is partly mediated by the general stress transcription factors Msn2p/Msn4p. The SWI/SNF ATP-dependent chromatin-remodeling complex associates with the promoter in a similar biphasic manner and is essential for both phases of transcription. Two different histone acetyltransferases, Gcn5p and Esa1p, enhance the binding of SWI/SNF to the promoter during early transcription and are required for optimal SUC2 induction. Gcn5p is recruited to SUC2 simultaneously with SWI/SNF, whereas Esa1p associates constitutively with the promoter. This study reveals an unusual transcription pattern of a metabolic gene and suggests a novel strategy by which distinct chromatin remodelers cooperate for the dynamic activation of transcription.