Identification of a high density lipoprotein binding protein from adrenocortical membranes

Abstract

A protein band with an apparent molecular weight of 78,000 daltons has been identified in the solubilised plasma membrane extract of sheep adrenal cortex which binds HDL 3 devoid of E apolipoprotein. Following ‘Western’ blotting, and development of the nitrocellulose strips with appropriate antisera and color reagent, the same band, unlike other cortical membrane proteins or albumin, bound AI and AII apolipoproteins. Human LDL bound weakly to the same band but more strongly to another two proteins of higher molecular weight. These studies confirm the same degree of specificity of HDL 3 binding found with cultured adrenal cells and strengthen the suggested existence of a specific HDL receptor.