Linked Life Data

9556612

Source:http://linkedlifedata.com/resource/pubmed/id/9556612

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
18
pubmed:dateCreated
1998-6-2
pubmed:abstractText
Macrophages in atherosclerotic lesions accumulate large amounts of cholesteryl-fatty acyl esters ("foam cell" formation) through the intracellular esterification of cholesterol by acyl-coenzyme A:cholesterol O-acyltransferase (ACAT). In this study, we sought to determine the subcellular localization of ACAT in macrophages. Using mouse peritoneal macrophages and immunofluorescence microscopy, we found that a major portion of ACAT was in a dense reticular cytoplasmic network and in the nuclear membrane that colocalized with the luminal endoplasmic reticulum marker protein-disulfide isomerase (PDI) and that was in a similar distribution as the membrane-bound endoplasmic reticulum marker ribophorin. Remarkably, another portion of the macrophage ACAT pattern did not overlap with PDI or ribophorin, but was found in as yet unidentified cytoplasmic structures that were juxtaposed to the nucleus. Compartments containing labeled beta-very low density lipoprotein, an atherogenic lipoprotein, did not overlap with the ACAT label, but rather were embedded in the dense reticular network of ACAT. Furthermore, cell-surface biotinylation experiments revealed that freshly harvested, non-attached macrophages, but not those attached to tissue culture dishes, contained approximately 10-15% of ACAT on the cell surface. In summary, ACAT was found in several sites in macrophages: a cytoplasmic reticular/nuclear membrane site that overlaps with PDI and ribophorin and has the characteristics of the endoplasmic reticulum, a perinuclear cytoplasmic site that does not overlap with PDI or ribophorin and may be another cytoplasmic structure or possibly a unique subcompartment of the endoplasmic reticulum, and a cell-surface site in non-attached macrophages. Understanding possible physiological differences of ACAT in these locations may reveal an important component of ACAT regulation and macrophage foam cell formation.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
273
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
11218-24
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Immunolocalization of acyl-coenzyme A:cholesterol O-acyltransferase in macrophages.
pubmed:affiliation
Department of Biochemistry, Cornell University Medical School, New York, New York 10021, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't