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Genome-wide Binding Potential and Regulatory Activity of the Glucocorticoid Receptor’s Monomeric and Dimeric Forms

ABSTRACT: A widely regarded model for glucocorticoid receptor (GR) action postulates that dimeric binding to DNA regulates unfavorable metabolic pathways while monomeric receptor binding promotes repressive gene responses related to its anti-inflammatory effects. This model has been built upon the characterization of the GRdim mutant, reported to be incapable of DNA binding and dimerization. Although quantitative live-cell imaging data shows GRdim as mostly dimeric, genomic studies, on the basis of recovery of enriched half-site response elements, suggest monomeric engagement on DNA. Here, we performed genome-wide studies on GRdim and a constitutively monomeric mutant. Our results show that impairing dimerization affects binding to even open chromatin. Also, GRdim does not exclusively bind half-response elements. Our results do not support a physiological role for monomeric GR and are consistent with a common mode of receptor binding via higher order structures that drives both the activating and repressive actions of glucocorticoids.

ORGANISM(S): Mus musculus

PROVIDER: GSE117661 | GEO | 2021/01/19

REPOSITORIES: GEO

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