A 70-kDa apolipoprotein designated ApoJ is a marker for subclasses of human plasma high density lipoproteins

Autor: William D. Stuart, H. V. De Silva, C. R. Duvic, J. R. Wetterau, M. J. Ray, Judith A.K. Harmony, H. W. Albers, W. R. Smith, Donald G. Ferguson
Rok vydání: 1990
Předmět:
Zdroj: Journal of Biological Chemistry. 265:13240-13247
ISSN: 0021-9258
DOI: 10.1016/s0021-9258(19)38290-0
Popis: 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.
Databáze: OpenAIRE