Detergent solubilized receptors

Detergent-solubilized receptors originate from cells that are transfected to overexpress the receptor of choice. The unpurified solubilized extracts contain other proteins including endogenous G proteins that are present in much higher concentrations than even the overexpressed target receptor. In normal cells, the expression of G proteins can be as much as 10-100 times higher than receptors (Ransnas and Insel, 1988). For the overexpressed receptor systems described here, it was determined by Western... 

The interaction of RBP with its membrane-bound receptor can be investigated using a variety of methods, all employing radioiodinated RBP. However, of all the methods used, the oil-centrifugation protocol described here (1) has been found to be the most reliable and sensitive. Methods to assay both the membrane-bound and the detergent-solubilized receptor are provided. In addition, a method for purifying the receptor from membranes is also included... 

Radioiodinated derivatives have been prepared to define more closely the target site of a-conotoxins on the acetylcholine receptor (R. Myers, unpublished data). In membrane preparations from Torpedo electroplax, photoactivatable azidosalicylate derivatives of a-conotoxin GIA preferentially label the p and 7 subunits of the acetylcholine receptor. However, when the photoactivatable derivative is cross-linked to detergent solubilized acetylcholine receptor (AChR), only the 7 subunit is labeled. Since snake a-neurotoxins mainly bind to the a subunits of AChR and a-conotoxins compete directly with a-bungarotoxin, the cross-linking results above are both intriguing and problematic. 

Venter JC, I larrison LC. Membranes, Detergents and Receptor Solubilization, Alan R. Liss, New York, 1984. 

Further confirmation of the absence of a receptor analogous to that of mammalian and avian species was obtained from binding studies carried out jLn vitro. Detergent solubilized preparations of freshly prepared homogenates, or acetone dried powders, of fish liver and kidney were assayed for specific binding activity as described previously (2, 3). In no case was it possible to... 

Hingorani, S.R., and Agnew, W. (1991). A Rapid Ion Exchange Assay for Detergent Solubilized Inositol 1,4,5-triphosphate Receptors, Biochem. 194 204—213. 

Perdue, J., et al. (1983). The Biochemical Characterization of Detergent-solubilized Insulin-like Growth Factor II Receptor from Rat Placenta, J. Biol. Chem. 258 7800-7811. 

Kylden, U. and Hammarstrom, S. (1980). Molecular weight of detergent-solubilized prostaglandin F2a receptor from bovine corpora lutea. Eur. ]. Biochem., 109, 489-494... 

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