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1n3y
From Proteopedia
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Crystal structure of the alpha-X beta2 integrin I domain
Overview
The integrin alpha X beta 2 (CD11c/CD18, p150,95) binds ligands through, the I domain of the alpha X subunit. Ligands include the complement factor, fragment iC3b, a key component in the innate immune defense, which, together with the expression of alpha X beta 2 on dendritic cells and on, other leukocytes, suggests a role in the immune response. We now report, the structure of the alpha X I domain resolved at 1.65 A by x-ray, crystallography. To analyze structural requirements for ligand binding we, made a mutation in the alpha X I domain C-terminal helix, which increased, the affinity for iC3b approximately 200-fold to 2.4 microM compared with, the wild-type domain affinity of approximately 400 microM. Gel permeation, chromatography supported a conformational change between the wild-type and, mutated domains. Conservation of allosteric regulation in the alpha X I, domain points to the functional importance of this phenomenon.
About this Structure
1N3Y is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Structure and allosteric regulation of the alpha X beta 2 integrin I domain., Vorup-Jensen T, Ostermeier C, Shimaoka M, Hommel U, Springer TA, Proc Natl Acad Sci U S A. 2003 Feb 18;100(4):1873-8. Epub 2003 Jan 28. PMID:12554829
Page seeded by OCA on Fri Feb 15 16:26:57 2008
