Function and selectivity of bromodomains in anchoring chromatin-modifying complexes to promoter nucleosomes.
The functions of the SAGA and SWI/SNF complexes are interrelated and can form stable "epigenetic marks" on promoters in vivo. Here we show that stable promoter occupancy by SWI/SNF and SAGA in the absence of transcription activators requires the bromodomains of the Swi2/Snf2 and Gcn5 subunits, respectively, and nucleosome acetylation. This acetylation can be brought about by either the SAGA or NuA4 HAT complexes. The bromodomain in the Spt7 subunit of SAGA is dispensable for this activity but will anchor SAGA if it is swapped into Gcn5, indicating that specificity of bromodomain function is determined in part by the subunit it occupies. Thus, bromodomains within the catalytic subunits of SAGA and SWI/SNF anchor these complexes to acetylated promoter nucleosomes.
Hassan
Ahmed H
AH
Howard Hughes Medical Institute, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, 306 Althouse Laboratory, University Park, PA 16802, USA.
Prochasson
Philippe
P
Neely
Kristen E
KE
Galasinski
Scott C
SC
Chandy
Mark
M
Carrozza
Michael J
MJ
Workman
Jerry L
JL
D000107:Acetylation; D000123:Acetyltransferases / Q000378:metabolism*; D002843:Chromatin / Q000378:metabolism* / Q000502:physiology; D004268:DNA-Binding Proteins / Q000378:metabolism*; D051548:Histone Acetyltransferases; D009687:Nuclear Proteins; D009707:Nucleosomes / Q000378:metabolism; D011401:Promoter Regions, Genetic / Q000502:physiology; D011494:Protein Kinases / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*; D015534:Trans-Activators / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism*; D000099224:p300-CBP-Associated Factor
D000123:Acetyltransferases; D002843:Chromatin; D004268:DNA-Binding Proteins; D051548:Histone Acetyltransferases; D009687:Nuclear Proteins; D009707:Nucleosomes; D011494:Protein Kinases; D029701:Saccharomyces cerevisiae Proteins; D015534:Trans-Activators; D014157:Transcription Factors; C070633:Gal-VP16; C093107:SPT7 protein, S cerevisiae; C501392:GCN5 protein, S cerevisiae; D000099224:p300-CBP-Associated Factor