de Silva H V, Stuart W D, Duvic C R, Wetterau J R, Ray M J, Ferguson D G, Albers H W, Smith W R, Harmony J A
Department of Pharmacology, University of Cincinnati, Ohio 45267.
J Biol Chem. 1990 Aug 5;265(22):13240-7.
A new apolipoprotein, termed apolipoprotein J (apoJ), was purified from human plasma by immunoaffinity chromatography. ApoJ is a glycoprotein consisting of disulfide-linked subunits of 34-36 and 36-39 kDa. Each subunit is glycosylated and has a pI range of 4.9-5.4. ApoJ exists in the plasma associated with high density lipoproteins (HDL) and specifically with subclasses of HDL which also contain apoAI and cholesteryl ester transfer protein activity. Immunoaffinity purified apoJ-HDL subclasses have apparent molecular masses of 80, 160, 240, 340, and 520 kDa, as determined by gradient gel electrophoresis. By negative staining electron microscopy, apoJ-HDL range in diameter from 5 to 16 nm. Fractionation of plasma by vertical gradient density centrifugation revealed apoJ-HDL in HDL2 (d 1.063-1.125 g/ml) with the majority overlapping HDL3 (d 1.125-1.21 g/ml) and very high density lipoprotein (d 1.21-1.25 g/ml). The bimodal density distribution of apoJ-HDL suggests that these subclasses have a unique metabolic relationship and may play a role in the transport of cholesterol from peripheral tissues to the liver.
一种新的载脂蛋白，称为载脂蛋白J（apoJ），通过免疫亲和色谱法从人血浆中纯化得到。apoJ是一种糖蛋白，由34 - 36 kDa和36 - 39 kDa的二硫键连接亚基组成。每个亚基都进行了糖基化，其等电点范围为4.9 - 5.4。apoJ存在于血浆中，与高密度脂蛋白（HDL）相关，特别是与也含有apoAI和胆固醇酯转移蛋白活性的HDL亚类相关。通过梯度凝胶电泳测定，免疫亲和纯化的apoJ - HDL亚类的表观分子量分别为80、160、240、340和520 kDa。通过负染电子显微镜观察，apoJ - HDL的直径范围为5至16 nm。通过垂直梯度密度离心对血浆进行分级分离，发现HDL2（密度1.063 - 1.125 g/ml）中有apoJ - HDL，其中大部分与HDL3（密度1.125 - 1.21 g/ml）和极高密度脂蛋白（密度1.21 - 1.25 g/ml）重叠。apoJ - HDL的双峰密度分布表明这些亚类具有独特的代谢关系，可能在胆固醇从外周组织向肝脏的转运中起作用。
