Article

The Dynamic Structure of the Estrogen Receptor

Department of Basic Sciences, The Commonwealth Medical College, Scranton, PA 18510, USA.
Journal of amino acids 07/2011; 2011:812540. DOI: 10.4061/2011/812540
Source: PubMed

ABSTRACT

The estrogen receptor (ER) mediates most of the biological effects of estrogens at the level of gene regulation by interacting through its site-specific DNA and with other coregulatory proteins. In recent years, new information regarding the dynamic structural nature of ER has emerged. The physiological effects of estrogen are manifested through ER's two isoforms, ER(α) and ER(β). These two isoforms (ER(α) and ER(β)) display distinct regions of sequence homology. The three-dimensional structures of the DNA-binding domain (DBD) and ligand-binding domain (LBD) have been solved, whereas no three-dimensional natively folded structure for the ER N-terminal domain (NTD) is available to date. However, insights about the structural and functional correlations regarding the ER NTD have recently emerged. In this paper, we discuss the knowledge about the structural characteristics of the ER in general and how the structural features of the two isoforms differ, and its subsequent role in gene regulation.

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Available from: Gianluca Toraldo, Jan 01, 2014
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    • "Among the sex steroid receptors, only ERs possess a welldefined F domain (Fig. 1). This region is relatively unstructured with little known function, although some data indicate a role in coactivator recruitment,(2012)Mediator 'Bridges' ER and transcriptionaldimerization and receptor stability (Katzenellenbogen et al. 2000, Koide et al. 2007, Yang et al. 2008, Kumar et al. 2011, Arao et al. 2013).). SRC1 (NCOA1), SRC2 (GRIP1 and TIF2), and SRC3 (pCIP, RAC3, ACTR, TRAM, and A1B1) interact with helix 12 of ERs via 'LXXLL' motifs in their nuclear receptor interacting domains, which are leucine rich regions with 'X' designating any amino acid (Johnson & O'Malley 2012). "
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    • "The full transcriptional activity of the human estrogen receptor is dependent on synergism between AF-2 and AF-1 (hormone-independent activation function) (Kumar et al., 2011). Taken together, all of the elements are highly conserved in the selected species compared to humans, which demonstrates that this estrogen receptor is highly conserved in mollusks. "
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