Linked Life Data

16497666

Source:http://linkedlifedata.com/resource/pubmed/id/16497666

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
17
pubmed:dateCreated
2006-4-24
pubmed:abstractText
One of the conserved functional pathways linked to engulfment of apoptotic corpses involves two membrane proteins low density lipoprotein receptor-related protein-1 (LRP) and ABCA1 and the LRP adapter protein GULP. Because LRP and ABCA1 play roles in cellular lipid trafficking and efflux, here we addressed whether the third member, the LRP adapter protein GULP, also affects cellular lipid transport. Several lines of evidence show that overexpression of GULP causes glycosphingolipid and free cholesterol accumulation in the late endosome/lysosome compartment that is accompanied by down-regulation of ABCA1 and decreased efflux. Conversely, knockdown of endogenous GULP expression promoted cholesterol flux through the late endosomes and up-regulation of ABCA1, even in the context of a disease state such as Niemann-Pick Type C disease. Mechanistically, we were able to show that trafficking of the LRP ligands alpha2-macroglobulin and prosaposin, a protein cofactor necessary for glycosphingolipid degradation, are impaired in cells expressing full-length GULP protein, resulting in glycosphingolipid and free cholesterol accumulation in the late endosome/lysosome compartment. On the other hand, knockdown of endogenous GULP results in enhanced targeting of prosaposin and enhanced clearance of glycosphingolipids and cholesterol from the late endosomes. Taken together, these data reveal that GULP/LRP/ABCA1 represents a triad of molecules involved in engulfment and cellular lipid homeostasis.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
28
pubmed:volume
281
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
12081-92
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
The lipoprotein receptor-related protein-1 (LRP) adapter protein GULP mediates trafficking of the LRP ligand prosaposin, leading to sphingolipid and free cholesterol accumulation in late endosomes and impaired efflux.
pubmed:affiliation
Lipoprotein and Atherosclerosis Research Group, Department of Pathology and Laboratory Medicine, University of Ottawa Heart Institute, Ottawa K1Y 4W7, Canada.
pubmed:publicationType
Journal Article, Comparative Study