Ottnad E, Via D P, Sinn H, Friedrich E, Ziegler R, Dresel H A
Department of Medicine, University of Heidelberg, Federal Republic of Germany.
Biochem J. 1988 Aug 1;253(3):835-8. doi: 10.1042/bj2530835.
Membranes from rat liver were analysed under reducing conditions. The components of the soluble membranes responsible for the binding of acetylated low density lipoprotein (acetyl-LDL) and maleylated bovine serum albumin (Mal-BSA) were chromatographed on a polyethyleneimine-cellulose column and subsequently separated by gel electrophoresis. For both ligands a major binding protein (Mr = 35,000) was revealed by ligand blotting. A minor protein (Mr greater than 67,000) exhibited little binding. The Scatchard plot of the 131I-Mal-BSA binding data of the 35 kDa protein was linear, with a Kd of 17.3 nM. High concentrations of acetyl-LDL competed for half of the 131I-Mal-BSA binding. Excessive Mal-BSA competed for all the visible acetyl-LDL binding. The findings indicate the existence, in the reduced hepatic membrane, of a 35 kDa protein that has two binding sites for 131I-Mal-BSA and one binding site for acetyl-LDL.
在还原条件下对大鼠肝脏膜进行分析。负责结合乙酰化低密度脂蛋白（乙酰-LDL）和马来酰化牛血清白蛋白（Mal-BSA）的可溶性膜成分在聚乙烯亚胺-纤维素柱上进行层析，随后通过凝胶电泳分离。对于这两种配体，通过配体印迹法揭示了一种主要的结合蛋白（Mr = 35,000）。一种次要蛋白（Mr大于67,000）几乎没有结合。35 kDa蛋白的131I-Mal-BSA结合数据的Scatchard图呈线性，Kd为17.3 nM。高浓度的乙酰-LDL竞争了一半的131I-Mal-BSA结合。过量的Mal-BSA竞争了所有可见的乙酰-LDL结合。这些发现表明，在还原的肝细胞膜中存在一种35 kDa的蛋白，它有两个131I-Mal-BSA结合位点和一个乙酰-LDL结合位点。
