RSC exploits histone acetylation to abrogate the nucleosomal block to RNA polymerase II elongation.
The coordinated action of histone acetyltransferases (HATs) and ATP-dependent chromatin remodeling enzymes in promoter-dependent transcription initiation represents a paradigm for how epigenetic information regulates gene expression. However, little is known about how such enzymes function during transcription elongation. Here, we investigated the role of RSC, a bromodomain-containing ATPase, in nucleosome transcription in vitro. Purified S. cerevisiae RNA polymerase II (Pol II) arrests at two primary locations on a positioned mononucleosome. RSC stimulates passage of Pol II through these sites. The function of RSC in elongation requires the energy of ATP hydrolysis. Moreover, the SAGA and NuA4 HATs strongly stimulated RSC's effect on elongation. The stimulation correlates closely with acetyl-CoA-dependent recruitment of RSC to nucleosomes. Thus, RSC can recognize acetylated nucleosomes and facilitate passage of Pol II through them. These data support the view that histone modifications regulate accessibility of the coding region to Pol II.
Carey
Michael
M
Stowers Medical Research Institute, 1000 East 50th Street, Kansas City, Missouri 64110, USA.
Li
Bing
B
Workman
Jerry L
JL
D000107:Acetylation; D000123:Acetyltransferases / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D042002:Chromatin Assembly and Disassembly / Q000235:genetics; D004268:DNA-Binding Proteins / Q000378:metabolism*; D051548:Histone Acetyltransferases; D006657:Histones / Q000378:metabolism*; D009707:Nucleosomes / Q000378:metabolism*; D011485:Protein Binding; D012319:RNA Polymerase II / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*; D015534:Trans-Activators / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism*; D014982:Xenopus laevis
D004268:DNA-Binding Proteins; D006657:Histones; D009707:Nucleosomes; C103337:RSC complex, S cerevisiae; C507785:SAGA complex, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D000255:Adenosine Triphosphate; D000123:Acetyltransferases; D051548:Histone Acetyltransferases; C504740:NuA4 protein, S cerevisiae; D012319:RNA Polymerase II