HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Burkey, B. F. Articles by Harmony, J. A. Search for Related Content PubMed PubMed Citation Articles by Burkey, B. F. Articles by Harmony, J. A. Social Bookmarking                      What's this?

Journal of Lipid Research, Vol 33, 1517-1526, Copyright © 1992 by Lipid Research, Inc.

ARTICLES

Hepatic apolipoprotein J is secreted as a lipoprotein

BF Burkey, WD Stuart and JA Harmony
Developmental Biology Program, University of Cincinnati, College of Medicine, OH 45267-0575.

Apolipoprotein J (apoJ) is a unique glycoprotein thought to be involved in a variety of physiological processes, including lipid transport, regulation of complement function, sperm maturation, programmed cell death, and membrane recycling. In the plasma, apoJ is associated with apoA-I in high and very high density lipoproteins. In this report we demonstrate that HepG2 human hepatocellular carcinoma cells secrete apoJ in association with a significant amount of lipid, providing unequivocal evidence that apoJ can transport lipids. The HepG2 cell line has provided important clues about the structural organization of nascent lipoprotein particles. HepG2 cell apoJ-containing lipoproteins are dense and heterogenous in size, ranging from 100 to 910 kDa. Plasma and HepG2 cell apoJ-lipoproteins differ in size distribution. Both have alpha 2 electrophoretic mobility, although their average mobilities differ within the alpha 2 region. In contrast to plasma apoJ-HDL which contain little triglyceride and which can associate with apoA-I, HepG2 cell apoJ-lipoproteins are rich in triglyceride and lack apoA-I. By implication, nascent apoJ-lipoproteins undergo plasma remodeling that results in triglyceride depletion and apoA-I association. We propose that the metabolic consequences of this remodeling play an important role in lipid homeostasis in localized tissue environments, particularly where organs are isolated from the blood by cellular barriers such as in testis and brain. In such tissues, apoJ is expressed constitutively in high level compared to other lipid transport proteins.
CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				D. R. Cochrane, Z. Wang, M. Muramaki, M. E. Gleave, and C. C. Nelson Differential Regulation of Clusterin and Its Isoforms by Androgens in Prostate Cells J. Biol. Chem., January 26, 2007; 282(4): 2278 - 2287. [Abstract] [Full Text] [PDF]

				A. E. Lavers, D. J. Swanlund, B. A. Hunter, M. L. Tran, J. L. Pryor, and K. P. Roberts Acute Effect of Vasectomy on the Function of the Rat Epididymal Epithelium and Vas Deferens J Androl, November 1, 2006; 27(6): 826 - 836. [Abstract] [Full Text] [PDF]

				A. Matsuda, Y. Itoh, N. Koshikawa, T. Akizawa, I. Yana, and M. Seiki Clusterin, an Abundant Serum Factor, Is a Possible Negative Regulator of MT6-MMP/MMP-25 Produced by Neutrophils J. Biol. Chem., September 19, 2003; 278(38): 36350 - 36357. [Abstract] [Full Text] [PDF]

				T. M. Forte, M. N. Oda, L. Knoff, B. Frei, J. Suh, J. A. K. Harmony, W. D. Stuart, E. M. Rubin, and D. S. Ng Targeted disruption of the murine lecithin:cholesterol acyltransferase gene is associated with reductions in plasma paraoxonase and platelet-activating factor acetylhydrolase activities but not in apolipoprotein J concentration J. Lipid Res., July 1, 1999; 40(7): 1276 - 1283. [Abstract] [Full Text]

				Q. Xu, Y. Li, C. Cyras, D. A. Sanan, and B. Cordell Isolation and Characterization of Apolipoproteins from Murine Microglia. IDENTIFICATION OF A LOW DENSITY LIPOPROTEIN-LIKE APOLIPOPROTEIN J-RICH BUT E-POOR SPHERICAL PARTICLE J. Biol. Chem., October 6, 2000; 275(41): 31770 - 31777. [Abstract] [Full Text] [PDF]

				R. A. Girton, D. P. Sundin, and M. E. Rosenberg Clusterin protects renal tubular epithelial cells from gentamicin-mediated cytotoxicity Am J Physiol Renal Physiol, April 1, 2002; 282(4): F703 - F709. [Abstract] [Full Text] [PDF]