Linked Life Data

15766265

Source:http://linkedlifedata.com/resource/pubmed/id/15766265

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2005-3-15
pubmed:abstractText
Interactions between the complement degradation product C3bi and leukocyte integrin alpha(M)beta(2) are critical for host defense against foreign pathogens and in tumor cell surveillance. To gain insight into the mechanism by which the alpha(M)I-domain of the integrin interacts with C3bi, detailed mapping of the C3bi binding site was undertaken. Previous mutagenesis studies had implicated five small structural segments within the alpha(M)I-domain in recognition of this ligand. Sets of three amino acids within the five implicated segments were mutated to the corresponding alpha(L)I-domain residues. Then, within the affected mutants, single point mutations were introduced to precisely define the requisite residues. Ultimately, H148, F150, Q204, L205, R208, T211, T213, I256, P257 were identified as being critical for C3bi binding. A synthetic peptide approach confirmed the involvement of the specified residues with the complex midsegment, Q204-I215, in C3bi recognition. Furthermore, the alpha(D)I-domain, which has a low intrinsic affinity for C3bi, acquired high affinity for the ligand when the implicated residues were inserted. The residues necessary to engage C3bi reside on or adjacent to the cation binding MIDAS site of the alpha(M)I-domain. The amino acids involved in C3bi binding are distinct from those involved in interaction of previously mapped ligands with the alpha(M)I-domain. This divergence supports a mosaic model, in which different ligands engage different amino acids to bind to alpha(M)I-domain, accounting for the broad recognition capacity of integrin alpha(M)beta(2).
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
22
pubmed:volume
44
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4357-64
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Identity of the amino acid residues involved in C3bi binding to the I-domain supports a mosaic model to explain the broad ligand repertoire of integrin alpha M beta 2.
pubmed:affiliation
Joseph J. Jacobs Center for Thrombosis and Vascular Biology and Department of Molecular Cardiology, The Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, Ohio 44195, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't