Steroid-binding domain

Steroid hormone receptors are phosphoproteins that have a DNA-binding domain and a steroid-binding domain 851... 

Steroid hormone receptors are phosphoproteins that have a DNA-binding domain and a steroid-binding domain. All steroid receptors have a molecular weight of 55,000-120,000. The state of phosphorylation appears to influence functional activity. 

Flavonoids are now regarded as a class of MDR modulators that directly interact with nucleotide and steroid binding domains of P-gp. However, the molecular mechanism leading to inhibition of MRP1 transport activity by these compounds is still far from being fully understood. Apart from interaction with NBD or substrate binding sites, the stimulation of GSH transport carried by MRP1 and depletion of cellular GSH was also proposed as a possible mechanism of MRPl-mediated resistance reversal by flavonoids [223]. 

Xu M, Chakraborti PK, Garabedian MJ, Yamamoto KR, Simons SS Jr. Modular structure of glucocorticoid receptor domains is not equivalent to functional independence. Stability and activity of the steroid binding domain are controlled by sequences in separate domains. J. Biol. Chem. 1996 271 21430-21438. Chakraborti PK, Garabedian MJ, Yamamoto KR, Simons SS Jr. Creation of super glucocorticoid receptors by point mutations in the steroid binding domain. J. Biol. Chem. 1991 266 22075-22078. 

Picard D, Salser SJ, Yamamoto KR. A movable and regulable inactivation function within the steroid binding domain of the 55. glucocorticoid receptor. Cell 1988 54 1073-1080. 

Colombe, L., A. Fostier, N. Bury, F. Pakdel and Y. Guiguen. A mineralocorticoid-like receptor in the rainbow trout, Oncorhynchus mykiss cloning and characterization of its steroid binding domain. Steroids 65 319-328, 2000. 

Carlstedt-Duke, J, Stromstedt, P.-E., Persson, B., Cederlund, E., Gustafsson, J.-A., and JdmvaU, H., Identification of hormone-interacting amino acid residues within the steroid-binding domain of the glucocorticoid receptor in relation to other steroid hormone receptors, J. Biol. Chem., 263, 6842-6848, 1988. 

Fig. 14.17. Stereo view of the C backbone of the steroid-binding domain of cholesterol oxidase showing the proposed entrance to the active site. The FAD molecule is shown in thick lines. The mobile loops believed to be situated near the proposed entrance are also shown in thick lines [57]...

The absence of specific 1,25-(0H)2[ H]D3 binding activity in HL-60 cell preparations is due to proteolysis of the 1,25-(0H)2[ H]D3 receptor (Inaba and DeLuca 1989). An endogenous proteinase may act on the steroid-binding domain of the 1,25-(0H)2D3 receptor or in its immediate vicinity, because it destroyed the l,25-(OH)2D3-binding ability of unoccupied receptor, but did not digest occupied receptor. The proteinase appeared to belong to the serine class of proteases, which is specifically inhibited with diisopropylfluorophosphate and not hydrolysed diisopropylfluorophosphate. 

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