Linked Life Data

12756261

Source:http://linkedlifedata.com/resource/pubmed/id/12756261

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
32
pubmed:dateCreated
2003-8-4
pubmed:abstractText
Ca2+-dependent membrane interaction has long been recognized as a general property of the annexin (ANX) family of proteins. More recently, it has become clear that ANXs can also undergo Ca2+-independent membrane interactions at mildly acidic pH. Here we use site-directed spin labeling in combination with circular dichroism and biochemical labeling methods to compare the structure and membrane topography of these two different membrane-bound forms of ANX12. Our results reveal strong similarities between the solution structure and the structure of the Ca2+-dependent membrane-bound form at neutral pH. In contrast, all Ca2+-independent membrane interactions tested resulted in large scale conformational changes and membrane insertion. Pairs of spin labels that were in close proximity across the interface of different domains of the protein in both the soluble and Ca2+-dependent membrane form were >25 A apart in the Ca2+-independent membrane-bound form. Despite these major conformational changes, the overall secondary structure content did not appear to be strongly altered and ANX12 remained largely helical. Thus, Ca2+-independent membrane interaction leads to massive refolding but not unfolding. Refolding did not occur at low pH in the absence of membranes but occurred within a few seconds after phospholipid vesicles were added. The phospholipid composition of the vesicles was an important modulator of Ca2+-independent membrane interaction. For example, cardiolipin-containing vesicles induced Ca2+-independent membrane interaction even at near neutral pH, thereby raising the possibility that lipid composition could induce relatively rapid Ca2+-independent membrane interaction in vivo.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
8
pubmed:volume
278
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
30227-34
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:12756261-Animals, pubmed-meshheading:12756261-Annexins, pubmed-meshheading:12756261-Calcium, pubmed-meshheading:12756261-Cardiolipins, pubmed-meshheading:12756261-Cattle, pubmed-meshheading:12756261-Cell Membrane, pubmed-meshheading:12756261-Circular Dichroism, pubmed-meshheading:12756261-Crystallography, X-Ray, pubmed-meshheading:12756261-Electron Spin Resonance Spectroscopy, pubmed-meshheading:12756261-Hydrogen-Ion Concentration, pubmed-meshheading:12756261-Kinetics, pubmed-meshheading:12756261-Models, Molecular, pubmed-meshheading:12756261-Mutation, pubmed-meshheading:12756261-Phospholipids, pubmed-meshheading:12756261-Protein Conformation, pubmed-meshheading:12756261-Protein Denaturation, pubmed-meshheading:12756261-Protein Folding, pubmed-meshheading:12756261-Protein Structure, Secondary, pubmed-meshheading:12756261-Spin Labels, pubmed-meshheading:12756261-Time Factors, pubmed-meshheading:12756261-Ultraviolet Rays
pubmed:year
2003
pubmed:articleTitle
Global structural changes in annexin 12. The roles of phospholipid, Ca2+, and pH.
pubmed:affiliation
Department of Biochemistry and Molecular Biology, Keck School of Medicine, Zilkha Neurogenetic Institute and Arnold and Mabel Beckman Macular Research Center, University of Southern California, Los Angeles, California 90033, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.