GSE98259
Promoter DNA sequence guides factors that position the +1 nucleosome and facilitate TBP binding [sequencing]
Here we present evidence that precise positioning of the +1 promoter nucleosome in yeast is critical for efficient TBP binding and pre-initiation complex assembly, and is determined, at least in part, by the action of two key factors, the essential chromatin remodeler RSC and one (or more) of a small set of ubiquitous pioneer transcription factors (PTFs). Despite their widespread co-localization, we show that RSC and PTFs often act independently to generate accessible chromatin. Furthermore, we present evidence that RSC binding, as well as the strength and directionality of its action on nucleosomes, depends upon the arrangement of two specific DNA motifs relative to nearby PTF binding sites. Our results provide insights into how promoter DNA sequence instructs trans-acting factors to precisely control nucleosome architecture and stimulate transcription initiation. Overall design: Nucleosome occupancy as well as TBP binding was measured upon depletion of Abf1, Reb1, Rap1 and/or the catalytic subunit of chromatin remodeler RSC. For the yeast strain background used in this study, Rapamycin causes depletion from the nucleus of the proteins tagged with the FRB peptide following the "anchor away" protocol published in PMID: 18922474.