Linked Life Data

14701819

Source:http://linkedlifedata.com/resource/pubmed/id/14701819

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
2004-3-15
pubmed:abstractText
Annexin 2 belongs to the annexin family of proteins that bind to phospholipid membranes in a Ca(2+)-dependent manner. Here we show that, under mild acidic conditions, annexin 2 binds to and aggregates membranes containing anionic phospholipids, a fact that questions the mechanism of its interaction with membranes via Ca(2+) bridges only. The H(+) sensitivity of annexin 2-mediated aggregation is modulated by lipid composition (i.e. cholesterol content). Cryo-electron microscopy of aggregated liposomes revealed that both the monomeric and the tetrameric forms of the protein form bridges between the liposomes at acidic pH. Monomeric annexin 2 induced two different organizations of the membrane junctions. The first resembled that obtained at pH 7 in the presence of Ca(2+). For the tetramer, the arrangement was different. These bridges seemed more flexible than the Ca(2+)-mediated junctions allowing the invagination of membranes. Time-resolved fluorescence analysis at mild acidic pH and the measurement of Stokes radius revealed that the protein undergoes conformational changes similar to those induced by Ca(2+). Labeling with the lipophilic probe 3-(trifluoromethyl)-3-(m-[(125)I]iodophenyl)diazirine indicated that the protein has access to the hydrophobic part of the membrane at both acidic pH in the absence of Ca(2+) and at neutral pH in the presence of Ca(2+). Models for the membrane interactions of annexin 2 at neutral pH in the presence of Ca(2+) and at acidic pH are discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
19
pubmed:volume
279
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
10872-82
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2004
pubmed:articleTitle
Novel organization and properties of annexin 2-membrane complexes.
pubmed:affiliation
Unité de Biologie Cellulaire et Moléculaire de la Sécrétion, CNRS UPR 1929, Institut de Biologie Physico-Chimique, 75005 Paris, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't