Linked Life Data

11861660

Source:http://linkedlifedata.com/resource/pubmed/id/11861660

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2002-2-25
pubmed:abstractText
Interactions of apolipoprotein A-I (apoA-I) with cell membranes appear to be important in the initial steps of reverse cholesterol transport. The objective of this work was to examine the effect of three distinct conformations of apoA-I (lipid-free and in 78 A or 96 A reconstituted high density lipoproteins, rHDL) on its ability to bind to, and abstract lipids from, palmitoyl oleoyl phosphatidylcholine membrane vesicles (small unilamellar vesicles, SUV, and giant unilamellar vesicles, GUV). The molecular interactions were observed by two-photon fluorescence microscopy, and the binding parameters were quantified by gel-permeation chromatography or isothermal titration microcalorimetry. Rearrangement of apoA-I-containing particles after exposure to SUVs was examined by native gel electrophoresis. The results indicate that lipid-free apoA-I binds reversibly, with high affinity, to the vesicles but does not abstract a significant amount of lipid nor perturb the vesicle structure. The 96 A rHDL, where all the amphipathic helices of apoA-I are saturated with lipid within the particles, do not bind to vesicles or perturb their structure. In contrast, the 78 A rHDL have a region of apoA-I, corresponding to a few amphipathic helical segments, which is available for external or internal phospholipid binding. These particles bind to vesicles with measurable affinity (lower than lipid-free apoA-I), abstract lipids from the membranes, and form particles of larger diameters, including 96 A rHDL. We conclude that the conformation of apoA-I regulates its binding affinity for phospholipid membranes and its ability to abstract lipids from the membranes.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0022-2275
pubmed:author
pubmed:issnType
Print
pubmed:volume
43
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
187-97
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Interaction of apolipoprotein A-I in three different conformations with palmitoyl oleoyl phosphatidylcholine vesicles.
pubmed:affiliation
Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.