UMMS Affiliation
Department of Cell Biology
Publication Date
2005-05-05
Document Type
Article
Disciplines
Cell Biology | Life Sciences | Medicine and Health Sciences
Abstract
The activation of muscle-specific gene expression requires the coordinated action of muscle regulatory proteins and chromatin-remodeling enzymes. Microarray analysis performed in the presence or absence of a dominant-negative BRG1 ATPase demonstrated that approximately one-third of MyoD-induced genes were highly dependent on SWI/SNF enzymes. To understand the mechanism of activation, we performed chromatin immunoprecipitations analyzing the myogenin promoter. We found that H4 hyperacetylation preceded Brg1 binding in a MyoD-dependent manner but that MyoD binding occurred subsequent to H4 modification and Brg1 interaction. In the absence of functional SWI/SNF enzymes, muscle regulatory proteins did not bind to the myogenin promoter, thereby providing evidence for SWI/SNF-dependent activator binding. We observed that the homeodomain factor Pbx1, which cooperates with MyoD to stimulate myogenin expression, is constitutively bound to the myogenin promoter in a SWI/SNF-independent manner, suggesting a two-step mechanism in which MyoD initially interacts indirectly with the myogenin promoter and attracts chromatin-remodeling enzymes, which then facilitate direct binding by MyoD and other regulatory proteins.
DOI of Published Version
10.1128/MCB.25.10.3997-4009.2005
Source
Mol Cell Biol. 2005 May;25(10):3997-4009. Link to article on publisher's site
Journal/Book/Conference Title
Molecular and cellular biology
Related Resources
PubMed ID
15870273
Repository Citation
de la Serna IL, Ohkawa Y, Berkes CA, Bergstrom DA, Dacwag CS, Tapscott SJ, Imbalzano AN. (2005). MyoD targets chromatin remodeling complexes to the myogenin locus prior to forming a stable DNA-bound complex. GSBS Student Publications. https://doi.org/10.1128/MCB.25.10.3997-4009.2005. Retrieved from https://escholarship.umassmed.edu/gsbs_sp/264