人胚肝低密度脂蛋白受体的提纯和鉴别

PURIFICATION AND IDENTIFICATION OF LOW DENSITY LIPOPROTEIN RECEPTOR FROM HUMAN FETAL LIVERS

报道了用两步法快速分离人胚肝低密度脂蛋白受体的方法。肝细胞膜用非离子型去污剂TritonX-100溶解后,经DE52纤维素离子交换层析和LDL偶联的Sepharose 4B亲和层析,将受体纯化了500倍。纯化后的低密度脂蛋白受体具有完整细胞和粗制细胞膜上受体的所有特征:(1)能与^(125)I-LDL高亲和性结合,并呈现明显的剂量效应;(2)与LDL的结合需要Ca^(2+),EDTA可阻断其结合;(3)能与抗LDL受体的单克隆抗体相互作用;(4)分子量为130kd。

We deseribe a rapid two-step procedure for the purification of the lipoprotein(LDL) receptor from human fetal livers.Liver membranes were solubilized with nonionic detergent TritonX-100.After DEAE-cellulose and LDL=Sepharose 4B affinity chromatography,the product gives a purification of about 500-fold.The purified LDL receptor retained all the properties of the receptors of intact cells and crude membranes,e.g.,(1)it bound LDL with high affinity and saturation;(2)binding of LDL to this protein was absolutely dependent on Ca^(2+) and could be (?)bolished by EDTA;(3)it interacted with the monoclonal antibody against LDL receptor;(4)having a molecular weight of 130 Kd.