Linked Life Data

7629083

Source:http://linkedlifedata.com/resource/pubmed/id/7629083

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
30
pubmed:dateCreated
1995-9-5
pubmed:abstractText
Since reticulocytes have a high demand for iron, which is required for heme biosynthesis, these cells are highly specialized in the endocytosis of the iron carrier transferrin (Tf). From the resulting endocytic vesicles (EVs), iron is released and the vesicles rapidly return to the cell membrane where they fuse, causing the release of the apotransferrin. Due to a lack of other intracellular compartments, the endocytic vesicles can be readily isolated. In this study, we have investigated the fusogenic properties of EVs, using liposomes as target membranes. Membrane fusion was monitored by a lipid mixing assay based on the relief of fluorescence self-quenching, using octadecylrhodamine B-chloride (R18). Application of this procedure was verified and solidified by analysis of the fusion event by an independent lipid mixing assay, after in situ labeling of EVs, and by determination of the mixing of aqueous contents. We demonstrate that the endocytic vesicles are particularly prone to fuse with target membranes that contain dioleoylphosphatidylethanolamine (DOPE). Relative to DOPE, bilayers composed of phosphatidylserine or phosphatidylcholine show a reduced fusion activity with EV. The specific and strong inhibition of fusion by cyclosporin A and a peptide known to interfere with the propensity of DOPE to adopt the hexagonal HII phase suggests that the mechanism of fusion involves the ability of this lipid to readily adopt non-bilayer phases. ATP, GTP, and/or cytosol are not necessary to obtain fusion. However, trypsin treatment of the endocytic vesicles inhibits fusion, indicating the involvement of (a) protein(s) in the fusion event.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
28
pubmed:volume
270
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
17823-9
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
In vitro fusion of reticulocyte endocytic vesicles with liposomes.
pubmed:affiliation
URA 1856 CNRS, Université Montpellier II, France.
pubmed:publicationType
Journal Article