Analysis of Chromatin Dynamics during Glucocorticoid Receptor Activation

作者:Burd Craig J; Ward James M; Crusselle Davis Valerie J; Kissling Grace E; Phadke Dhiral; Shah Ruchir R; Archer Trevor K*
来源:Molecular and Cellular Biology, 2012, 32(10): 1805-1817.
DOI:10.1128/MCB.06206-11

摘要

Steroid hormone receptors initiate a genetic program tightly regulated by the chromatin environment of the responsive regions. Using the glucocorticoid receptor (GR) as a model factor for transcriptional initiation, we classified chromatin structure through formaldehyde-assisted isolation of regulatory elements (FAIRE). We looked at dynamic changes in FAIRE signals during GR activation specifically at regions of receptor interaction. We found a distribution of GR-responsive regions with diverse responses to activation and chromatin modulation. The majority of GR binding regions demonstrate increases in FAIRE signal in response to ligand. However, the majority GR-responsive regions shared a similar FAIRE signal in the basal chromatin state, suggesting a common chromatin structure for GR recruitment. Supporting this notion, global FAIRE sequencing (seq) data indicated an enrichment of signal surrounding the GR binding site prior to activation. Brg-1 knockdown showed response element-specific effects of ATPase-dependent chromatin remodeling. FAIRE induction was universally decreased by Brg-1 depletion, but to varying degrees in a target specific manner. Taken together, these data suggest classes of nuclear receptor response regions that react to activation through different chromatin regulatory events and identify a chromatin structure that classifies the majority of response elements tested.

  • 出版日期2012-5