title: Dissecting Steroid Receptor Function by Analytical Ultracentrifugation.
abstract: Steroid receptors comprise a family of ligand-activated transcription factors. The members include the androgen receptor (AR), estrogen receptor (ER), glucocorticoid receptor (GR), mineralocorticoid receptor (MR), and progesterone receptor (PR). Each receptor controls distinct sets of genes associated with development, metabolism, and homeostasis. Although a qualitative understanding of how individual receptors mediate gene expression has come into focus, quantitative insight remains less clear. As a step toward delineating the physical mechanisms by which individual receptors activate their target genes, we have carried out a systematic dissection of receptor interaction energetics with their multisite regulatory elements. Analytical ultracentrifugation (AUC) has proved indispensable in these studies, in part by revealing the energetics of receptor self-association and its thermodynamic coupling to DNA binding. Here, we discuss these findings in the context of understanding specificity of receptor-mediated gene control. We first highlight the role of sedimentation velocity and sedimentation equilibrium in addressing receptor assembly state, and present a comparative analysis across the receptor family. We then use these results for understanding how receptors assemble at multisite regulatory elements, and hypothesize how these findings might play a role in receptor-specific gene regulation. Finally, we examine receptor behavior in a cellular context, with a view toward linking our in vitro studies with in vivo function.
authors.affiliation: Department of Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA. Electronic address: david.bain@ucdenver.edu.
authors.forename: David L
authors.initials: DL
authors.lastname: Bain
authors.affiliation: Department of Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.
authors.forename: Rolando W
authors.initials: RW
authors.lastname: De Angelis
authors.affiliation: Department of Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.
authors.forename: Keith D
authors.initials: KD
authors.lastname: Connaghan
authors.affiliation: Department of Pharmaceutical Sciences, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.
authors.forename: Qin
authors.initials: Q
authors.lastname: Yang
authors.affiliation: Department of Pathology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.
authors.forename: Gregory D
authors.initials: GD
authors.lastname: Degala
authors.affiliation: Department of Pathology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA.
authors.forename: James R
authors.initials: JR
authors.lastname: Lambert
mesh_terms: D019143:Evolution, Molecular; D005786:Gene Expression Regulation; D006801:Humans; D020125:Mutation, Missense; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D055503:Protein Multimerization; D011987:Receptors, Steroid / Q000737:chemistry / Q000302:isolation & purification / Q000502:physiology*; D013816:Thermodynamics; D014461:Ultracentrifugation
chemical_list: D011987:Receptors, Steroid
keywords: Androgen receptor; Estrogen receptor; Glucocorticoid receptor; Nuclear hormone receptors; Protein–DNA interactions; Thermodynamics; Transcriptional regulation