Linked Life Data

11557679

Source:http://linkedlifedata.com/resource/pubmed/id/11557679

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
2001-9-14
pubmed:abstractText
Since the molecular identification of the low density lipoprotein receptor (LDLR), an ever increasing number of related proteins have been discovered. These receptors belonging to the LDLR family are thought to play key roles in lipoprotein metabolism in a variety of tissues, including the arterial wall. We have discovered that the expression of a 250-kDa mosaic LDLR-related protein, which we termed LR11 for the presence of 11 LDLR ligand-binding repeats, is markedly induced in smooth muscle cells in the hyperplastic intima of animal models used for the study of atherosclerosis. Here, we demonstrate that the human LR11, when overexpressed in hamster cells, binds and internalizes 39-kDa receptor-associated protein (RAP), an in vitro ligand for all receptors belonging to the LDLR family. Furthermore, LR11 binds the apolipoprotein E (apoE)-rich lipoproteins, beta-very low density lipoproteins (VLDLs), with a high affinity similar to that of other members, such as the LDLR and VLDL receptor. RAP and beta-VLDL compete with each other; however, other serum lipoproteins are not able to inhibit their binding. LR11 shows specific binding of apoE-enriched HDL prepared from human cerebrospinal fluid as well as of beta-VLDL, suggesting that the apoE content of lipoproteins is most likely important for mediating the high-affinity binding to the receptor. LR11-overexpressing cells are able to internalize and degrade the bound beta-VLDL; these cells also show increased accumulation of cholesteryl esters when incubated with beta-VLDL. Incubation for 48 hours with beta-VLDL of LR11-overexpressing cells, but not of control cells, promotes the appearance of numerous intracellular lipid droplets. Taken together, LR11, a mosaic LDLR family member whose expression in smooth muscle cells is markedly induced in atheroma, has all the properties of a receptor for the endocytosis of lipoproteins, particularly for the incorporation of apoE-rich lipoproteins.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1524-4636
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
21
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1501-6
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
LR11, a mosaic LDL receptor family member, mediates the uptake of ApoE-rich lipoproteins in vitro.
pubmed:affiliation
Department of Clinical Cell Biology, Graduate School of Medicine, Faculty of Pharmaceutical Sciences, Chiba University, Chiba, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't