Abstract 3560: The chromatin architecture at gucocorticoid receptor binding sites.

Abstract

Abstract Steroid hormone receptors are transcription factors that are implicated in the development and progression of several cancer types. It is clear that receptor activity is deregulated in these disease states. Using the glucocorticoid receptor (GR) as a model factor for transcriptional initiation, we aimed to understand the role chromatin structure plays in defining the specific genetic programs initiated by receptor activation. Using Formaldehyde Assisted Isolation of Regulatory Elements (FAIRE), we examined the chromatin state at GR binding locations. FAIRE-seq data indicated an enrichment of signal, suggesting a more open chromatin state, surrounding the GR binding sites even in the absence of hormone. This enrichment is only seen at binding sites and not at unutilized response elements. This data is in line with recent developments indicating accessibility as a determinant of receptor binding. However, further characterization of binding regions suggests consistent nucleosome occupancy at these binding locations. Taken together, these data suggest that receptor binding may be determined by a very specific chromatin architecture that is defined by a transitional accessibility state. Citation Format: Craig J. Burd, James M. Ward, Adam B. Burkholder, David C. Fargo, Trevor K. Archer. The chromatin architecture at gucocorticoid receptor binding sites. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3560. doi:10.1158/1538-7445.AM2013-3560