Linked Life Data

21388953

Source:http://linkedlifedata.com/resource/pubmed/id/21388953

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
19
pubmed:dateCreated
2011-5-9
pubmed:abstractText
The calcium- and integrin-binding protein 1 (CIB1) is a ubiquitous Ca(2+)-binding protein and a specific binding partner for the platelet integrin ?IIb cytoplasmic domain, which confers the key role of CIB1 in hemostasis. CIB1 is also known to be involved in apoptosis, embryogenesis, and the DNA damage response. In this study, the solution structures of both Ca(2+)-CIB1 and Mg(2+)-CIB1 were determined using solution-state NMR spectroscopy. The methyl groups of Ile, Leu, and Val were selectively protonated to compensate for the loss of protons due to deuteration. The solution structure of Ca(2+)-CIB1 possesses smaller opened EF-hands in its C-domain compared with available crystal structures. Ca(2+)-CIB1 and Mg(2+)-CIB1 have similar structures, but the N-lobe of Mg(2+)-CIB1 is slightly more opened than that of Ca(2+)-CIB1. Additional NMR experiments, such as chemical shift perturbation and methyl group solvent accessibility as measured by a nitroxide surface probe, were carried out to further characterize the structures of Ca(2+)-CIB1 and Mg(2+)-CIB1 as well as their interactions with the integrin ?IIb cytoplasmic domain. NMR measurements of backbone amide proton slow motion (microsecond to millisecond) dynamics confirmed that the C-terminal helix of Ca(2+)-CIB1 is displaced upon ?IIb binding. The EF-hand III of both Ca(2+)-CIB1 and Mg(2+)-CIB1 was identified to be directly involved in the interaction of CIB1 with ?IIb. Together, these data illustrate that CIB1 behaves quite differently from related EF-hand regulatory calcium-binding proteins, such as calmodulin or neuronal calcium sensor proteins.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
1083-351X
pubmed:author
pubmed:issnType
Electronic
pubmed:day
13
pubmed:volume
286
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
17181-92
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Solution structures of Ca2+-CIB1 and Mg2+-CIB1 and their interactions with the platelet integrin alphaIIb cytoplasmic domain.
pubmed:affiliation
Biochemistry Research Group, Department of Biological Sciences, University of Calgary, Calgary, Alberta T2N 1N4, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't