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

This Article Full Text Full Text (PDF) All Versions of this Article: M200191-JLR200v1 44/1/72    most recent 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 Chao, H. Articles by Kier, A. B. Search for Related Content PubMed PubMed Citation Articles by Chao, H. Articles by Kier, A. B. Social Bookmarking                      What's this?

Journal of Lipid Research, Vol. 44, 72-83, January 2003
Copyright © 2003 by Lipid Research, Inc.

ACBP and cholesterol differentially alter fatty acyl CoA utilization by microsomal ACAT

Hsu Chao^*, Minglong Zhou, Avery McIntosh, Friedhelm Schroeder and Ann B. Kier^1,*

^* Department of Pathobiology, Texas A&M University, TVMC College Station, TX 77843-4467
Department of Physiology and Pharmacology, Texas A&M University, TVMC College Station, TX 77843-4466

¹ To whom correspondence should be addressed. e-mail: akier{at}cvm.tamu.edu

Microsomal acyl CoA:cholesterol acyltransferase (ACAT) is stimulated in vitro and/or in intact cells by proteins that bind and transfer both substrates, cholesterol, and fatty acyl CoA. To resolve the role of fatty acyl CoA binding independent of cholesterol binding/transfer, a protein that exclusively binds fatty acyl CoA (acyl CoA binding protein, ACBP) was compared. ACBP contains an endoplasmic reticulum retention motif and significantly colocalized with acyl-CoA cholesteryl acyltransferase 2 (ACAT2) and endoplasmic reticulum markers in L-cell fibroblasts and hepatoma cells, respectively. In the presence of exogenous cholesterol, ACAT was stimulated in the order: ACBP > sterol carrier protein-2 (SCP-2) > liver fatty acid binding protein (L-FABP). Stimulation was in the same order as the relative affinities of the proteins for fatty acyl CoA. In contrast, in the absence of exogenous cholesterol, these proteins inhibited microsomal ACAT, but in the same order: ACBP > SCP-2 > L-FABP. The extracellular protein BSA stimulated microsomal ACAT regardless of the presence or absence of exogenous cholesterol.

Thus, ACBP was the most potent intracellular fatty acyl CoA binding protein in differentially modulating the activity of microsomal ACAT to form cholesteryl esters independent of cholesterol binding/transfer ability.

Abbreviations: ACAT1, acyl-CoA cholesteryl acyltransferase 1; ACAT2, acyl-CoA cholesteryl acyltransferase 2; ACBP, acyl-CoA binding protein; LCFA-CoA, long chain fatty acyl-CoA; L-FABP, liver fatty acid binding protein; SCP-2, sterol carrier protein-2

Supplementary key words microsome • acyl CoA cholesterol acyltransferase • acyl CoA binding protein

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				E. Soupene, V. Serikov, and F. A. Kuypers Characterization of an acyl-coenzyme A binding protein predominantly expressed in human primitive progenitor cells J. Lipid Res., May 1, 2008; 49(5): 1103 - 1112. [Abstract] [Full Text] [PDF]