Molecular Endocrinology, Vol 8, 422-430, Copyright © 1994 by Endocrine Society

ARTICLES

Phenylalanine-780 near the C-terminus of the mouse glucocorticoid receptor is important for ligand binding affinity and specificity

D Chen, K Kohli, S Zhang, M Danielsen and MR Stallcup
Department of Pathology, University of Southern California, Los Angeles 90033.

Site-directed mutagenesis was employed to make two single amino acid substitutions for highly conserved amino acid residues near the C- terminus of the 783-amino acid mouse glucocorticoid receptor. Substitution of leucine for histidine-781 caused little or no change in the concentration of dexamethasone required for half-maximal activation of a chloramphenicol acetyltransferase reporter gene expressed from a mouse mammary tumor virus promoter. However, when phenylalanine-780 was changed to alanine, the half-maximal concentrations of various agonists were increased as follows, compared with the wild-type glucocorticoid receptor: triamcinolone acetonide by 7-fold, dexamethasone by 25-fold, and hydrocortisone and deoxycorticosterone by more than 150-fold. Binding of labeled steroids by the mutant receptor in vitro and in vivo was also decreased. In contrast, this mutation caused a small decrease in the concentration of RU486 required for antagonist or partial agonist activity. Thus, the phenyl group of phenylalanine-780 of the mouse glucocorticoid receptor is an important determinant of ligand binding affinity and specificity.

This article has been cited by other articles:

				B. Farboud and M. L. Privalsky Retinoic Acid Receptor-{alpha} Is Stabilized in a Repressive State by Its C-Terminal, Isotype-Specific F Domain Mol. Endocrinol., December 1, 2004; 18(12): 2839 - 2853. [Abstract] [Full Text] [PDF]

				U. Lind, P. Greenidge, J.-A. Gustafsson, A. P. H. Wright, and J. Carlstedt-Duke Valine 571 Functions as a Regional Organizer in Programming the Glucocorticoid Receptor for Differential Binding of Glucocorticoids and Mineralocorticoids J. Biol. Chem., June 25, 1999; 274(26): 18515 - 18523. [Abstract] [Full Text] [PDF]

				S. Roux, B. Terouanne, B. Couette, M.-E. Rafestin-Oblin, and J.-C. Nicolas Conformational Change in the Human Glucocorticoid Receptor Induced by Ligand Binding Is Altered by Mutation of Isoleucine 747 by a Threonine J. Biol. Chem., April 9, 1999; 274(15): 10059 - 10065. [Abstract] [Full Text] [PDF]

				H. Hong, B. D. Darimont, H. Ma, L. Yang, K. R. Yamamoto, and M. R. Stallcup An Additional Region of Coactivator GRIP1 Required for Interaction with the Hormone-binding Domains of a Subset of Nuclear Receptors J. Biol. Chem., February 5, 1999; 274(6): 3496 - 3502. [Abstract] [Full Text] [PDF]

				J. Milhon, S. Lee, K. Kohli, D. Chen, H. Hong, and M. R. Stallcup Identification of Amino Acids in the {tau}2-Region of the Mouse Glucocorticoid Receptor That Contribute to Hormone Binding and Transcriptional Activation Mol. Endocrinol., November 1, 1997; 11(12): 1795 - 1805. [Abstract] [Full Text]

				P. D. Reynolds, S. J. Pittler, and J. G. Scammell Cloning and Expression of the Glucocorticoid Receptor from the Squirrel Monkey (Saimiri boliviensis boliviensis), a Glucocorticoid-Resistant Primate J. Clin. Endocrinol. Metab., February 1, 1997; 82(2): 465 - 472. [Abstract] [Full Text] [PDF]