Nigg E A, Bron C, Girardet M, Cherry R J
Biochemistry. 1980 Apr 29;19(9):1887-93. doi: 10.1021/bi00550a024.
A new approach to the study of molecular protein interactions in biological membranes is presented. The technique is based on measuring the rotation of a membrane protein in the presence and absence of specific antibodies directed toward a purported complex partner. As a first illustration of the method, the putative association of band 3 with glycophorin A in the human erythrocyte membrane was investigated. The rotational diffusion of band 3 was strongly reduced following cross-linking of glycophorin A with divalent antibodies. However, little or no effect on band 3 rotation was produced by monovalent antiglycophorin A Fab fragments, antispectrinor nonspecific antibodies, ruling out major effects on band 3 mobility due to steric hindrance, unspecific antibody adsorption, or transmembrane interactions involving spectrin. It is concluded that immobilization of band 3 by antiglycophorin A antibodies is directly caused by cross-linking of a preexisting band 3-glycophorin A complex in the human erythrocyte membrane.
本文提出了一种研究生物膜中分子蛋白相互作用的新方法。该技术基于在存在和不存在针对假定复合伴侣的特异性抗体的情况下测量膜蛋白的旋转。作为该方法的第一个例证，研究了人红细胞膜中带3与血型糖蛋白A的假定关联。用二价抗体交联血型糖蛋白A后，带3的旋转扩散显著降低。然而，单价抗血型糖蛋白A Fab片段、抗血影蛋白或非特异性抗体对带3的旋转几乎没有影响，排除了空间位阻、非特异性抗体吸附或涉及血影蛋白的跨膜相互作用对带3迁移率的主要影响。得出的结论是，抗血型糖蛋白A抗体对带3的固定是由人红细胞膜中预先存在的带3-血型糖蛋白A复合物的交联直接引起的。
