Steroid-protein interactions

W7. Westphal, U., Steroid-protein interactions. Monographs on Endocrinology, Vol. 4. Springer-Verlag, Berlin and New York, 1971. 

Canguly, M. and Westphal, U. (1968, Steroid-protein interactions. XVII. Influence of solvent environment on interaction between human ai-acid glycoprotein and progesterone. Journal of... 

Kute, T. and Westphal, U. (1976) Steroid-protein interactions. XXXIV. Chemical modification of a 1 -acid glycoprotein for characterization of the progesterone binding site. Biochimica el Biophysica Acta 420, 195-213. 

Westphal U. Steroid protein interactions, Monogr Endocrinol 1985 27 356-66. 

Westphal U. Steroid protein interactions. In Gross F, Labhart A, Mann T, al e, eds. Monographs on endocrinology. Berlin Springer-Veriag, 1986 211-19. 

Information concerning the molecular details of steroid-protein interactions can be obtained from X-ray analysis of crystalline complexes of proteins with appropriate steroid agonists and,antagonists, and from X-ray studies of model complexes of steroids with amino acids. 

Figure 3.2.2 (a) Classic model of a steroid-protein interaction, which only shows relative positions of functional groups, (b) Calculated point representation of the electrostatic potential on the van der Waals surface of the steroid. A similar surface potential distribution can be calculated for the protein receptor site, and both models can then be fitted. 

Burstein, E.A. and Emelyanenko, V. L, 1996, Log-normal description of fluorescence spectra of organic fluorophores. Photochemistry and Photobiology 64, 316-320. Ganguly, M. and Westphal, U. 1968, Steroid.protein interactions. XVll. Influence of solvent environment on interaction between human aj-acid glycoprotein and progesterone. Journal of Biological Chemistry 243, 6130-6139. 

U. Norinder, /. Camput.-Aided Mol. Design, 4, 381 (1990). Experimental Design Based 3-D QSAR Analysis of Steroid—Protein Interactions Application to Human CBG Complexes. 

Ligand-bound corticosteroid receptors have been shown to interact to form heterodimers with other transcription factors, such as the jun protein. Such interactions are responsible for transactivation of the ds-regulatory sites known as AP-1 sites and for the glucocorticoid-mediated suppression of transcription, such as that seen in the pro-opiomelanocortin gene. A number of such specific protein interactions have been reported these interactions and their locations relative to other transcription factors transform a ubiquitous steroid hormone signal into a tissue-specific, graded cellular response. 

In this way, although ERs participate in all cases and in all cells capable of responding to estrogens, the nature and intensity of the response is conditioned by the receptor interaction with three different types of molecules estrogen (steroid or not), DNA (through the HRE sequences), and the protein-protein interactions, including cofactors of transcription as well as elements of the signaling pathway from membrane receptors. 

P. Pavek, G. Merino, E. Wagenaar, E. Bolscher, M. Novotna, J.W. Jonker, and A.H. Schinkel. Human breast cancer resistance protein Interactions with steroid drugs, hormones, the dietary carcinogen 2-amino-l-methyl-6-phenylimidazo(4,5-b)pyridine, and transport of cimetidine. J Pharmacol Exp Ther. 312 144—152... 

Pratt WB, Toft DO. (1997) Steroid receptor interactions with heat shock protein and immu-nophilin chaperones. Endocr Rev. 18, 306-360. 

Free steroids that do not bind with plasma proteins enter target cells by passive diffusion and bind with cytoplasmic soluble-binding proteins (acceptor region), forming a steroid-protein complex. This enters the nucleus, where it interacts with steroid receptors on chromatin. 

With the help of co-immimoprecipitation it could be shown that the receptors of steroid hormones interact with at least three chaperones, Hsp90, Hsp70 and Hsp56 (fig. 4.10). The term Hsp (Heat shock protein) is derived from the observation that these proteins were produced at higher levels following heat treatment. Furthermore, one finds a 23 kDa acidic protein in the apo-receptor complex whose fimction is not yet clear. 

Grube M, Reuther S, Meyer Zu, et al. Organic anion transporting polypeptide 2B1 and breast cancer resistance protein interact in the transepithelial transport of steroid sulfates in human placenta. Drug Metah Dispos 2007 35 30-35. 

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