Linked Life Data

12534274

Source:http://linkedlifedata.com/resource/pubmed/id/12534274

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2003-1-21
pubmed:databankReference
pubmed:abstractText
Phosphorylation of some members of the annexin family of proteins may play a significant role in controlling their calcium-dependent interactions with membranes. Recent electron microscopic studies of annexin VI revealed that the protein's two core domains exhibit a great degree of flexibility and are able to undergo a relative conformational change that could potentially initiate contacts between membranes [Avila-Sakar, A. J., et al. (2000) J. Struct. Biol. 130, 54-62]. To assess the possibility of a regulatory role of phosphorylation in this behavior, the crystal structure of a phosphorylation-mimicking mutant (T356D in the flexible connector region of human annexin VI) was determined to 2.65 A resolution. When the mutant is compared to the wild-type annexin VI, subtle differences are seen at the site of the mutation, while larger changes are evident in one of the calcium-binding loops and in the presence of five calcium ions. Furthermore, biochemical studies provide evidence for additional conformational differences between the T356D and wild-type solution structures. Fluorescence emission and acrylamide quenching suggest a higher level of solvent exposure of Trp-343 in the connector region of T356D in the presence of calcium. Comparisons of retardation coefficients in native gel electrophoresis reveal that T356D has a more extended shape, while proteolytic studies show a greater accessibility of a trypsin cleavage site inside the linker region, indicating a conformation more open than the wild-type form. These data provide insights into a possible regulatory mechanism leading to a higher degree of flexibility and possibly a higher calcium binding affinity of annexin VI upon phosphorylation.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
28
pubmed:volume
42
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
620-30
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed-meshheading:12534274-Amino Acid Substitution, pubmed-meshheading:12534274-Animals, pubmed-meshheading:12534274-Annexin A6, pubmed-meshheading:12534274-Aspartic Acid, pubmed-meshheading:12534274-Calcium, pubmed-meshheading:12534274-Cattle, pubmed-meshheading:12534274-Crystallography, X-Ray, pubmed-meshheading:12534274-Electrophoresis, Polyacrylamide Gel, pubmed-meshheading:12534274-Hot Temperature, pubmed-meshheading:12534274-Humans, pubmed-meshheading:12534274-Hydrolysis, pubmed-meshheading:12534274-Liposomes, pubmed-meshheading:12534274-Molecular Mimicry, pubmed-meshheading:12534274-Mutagenesis, Site-Directed, pubmed-meshheading:12534274-Phosphorylation, pubmed-meshheading:12534274-Protein Binding, pubmed-meshheading:12534274-Protein Denaturation, pubmed-meshheading:12534274-Protein Folding, pubmed-meshheading:12534274-Solvents, pubmed-meshheading:12534274-Spectrometry, Fluorescence, pubmed-meshheading:12534274-Structure-Activity Relationship, pubmed-meshheading:12534274-Thermodynamics, pubmed-meshheading:12534274-Threonine, pubmed-meshheading:12534274-Trypsin
pubmed:year
2003
pubmed:articleTitle
Structural and dynamic changes in human annexin VI induced by a phosphorylation-mimicking mutation, T356D.
pubmed:affiliation
Department of Pharmacology, University of Virginia, Charlottesville, Virginia 22908, USA. cf9c@virginia.edu
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S.