Linked Life Data

11300800

Source:http://linkedlifedata.com/resource/pubmed/id/11300800

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
13
pubmed:dateCreated
2001-4-13
pubmed:databankReference
pubmed:abstractText
Site-directed mutagenesis, electron microscopy, and X-ray crystallography were used to probe the structural basis of annexin IV-induced membrane aggregation and the inhibition of this property by protein kinase C phosphorylation. Site-directed mutants that either mimic (Thr6Asp, T6D) or prevent (Thr6Ala, T6A) phosphorylation of threonine 6 were produced for these studies and compared with wild-type annexin IV. In vitro assays showed that unmodified wild-type annexin IV and the T6A mutant, but not PKC-phosphorylated wild-type or the T6D mutant, promote vesicle aggregation. Electron crystallographic data of wild-type and T6D annexin IV revealed that, similar to annexin V, the annexin IV proteins form 2D trimer-based ordered arrays on phospholipid monolayers. Cryo-electron microscopic images of junctions formed between lipid vesicles in the presence of wild-type annexin IV indicated a separation distance corresponding to the thickness of two layers of membrane-bound annexin IV. In this orientation, a single layer of WT annexin IV, attached to the outer leaflet of one vesicle, would undergo face-to-face self-association with the annexin layer of a second vesicle. The 2.0-A resolution crystal structure of the T6D mutant showed that the mutation causes release of the N-terminal tail from the protein core. This change would preclude the face-to-face annexin self-association required to aggregate vesicles. The data suggest that reversible complex formation through phosphorylation and dephosphorylation could occur in vivo and play a role in the regulation of vesicle trafficking following changes in physiological states.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
3
pubmed:volume
40
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4192-9
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Phosphorylation mutants elucidate the mechanism of annexin IV-mediated membrane aggregation.
pubmed:affiliation
Departments of Molecular and Cellular Physiology and of Obstetrics and Gynecology, University of Cincinnati, College of Medicine, Ohio 45220, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't