Related Experiment Videos
Properties of solubilized and reconstituted A1 adenosine receptors from bovine brain
E Ragazzi1, J Shryock, K Palczewski
1Department of Medicine, College of Medicine, University of Florida, Gainesville 32610.
Abstract:
A simple method for solubilization and reconstitution of the A1 adenosine receptor from bovine brain is presented. Solubilization with CHAPS-phosphatidylcholine (CHAPS/PC) mixture did not alter the binding properties of the A1 adenosine receptor antagonist [3H]-DPCPX. The solubilized receptors were chromatographed on hydroxyapatite or DEAE-cellulose to remove native membrane lipids and part of non-receptor proteins. Elution of the receptor fractions was obtained from DEAE-cellulose column with a linear gradient of KCl (0-0.4 M). The fractions corresponding to the peak of [3H]-DPCPX binding activity were then reconstituted in phosphatidylcholine by dialysis. The reconstituted receptor retained all the binding characteristics and the same rank order of competition potency (R-PIA greater than S-PIA greater than NECA) as the native receptor, although its thermal stability was remarkably reduced. The binding of [3H]-DPCPX to A1 adenosine receptors was increased by GTP, probably as result of interactions with coeluted G-proteins.