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Structure of complement receptor 2 in complex with its C3d ligand.

G Szakonyi·J M Guthridge·D Li·K Young·V M Holers·X S Chen
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Abstract

Complement receptor 2 (CR2/CD21) is an important receptor that amplifies B lymphocyte activation by bridging the innate and adaptive immune systems. CR2 ligands include complement C3d and Epstein-Barr virus glycoprotein 350/220. We describe the x-ray structure of this CR2 domain in complex with C3d at 2.0 angstroms. The structure reveals extensive main chain interactions between C3d and only one short consensus repeat (SCR) of CR2 and substantial SCR side-side packing. These results provide a detailed understanding of receptor-ligand interactions in this protein family and reveal potential target sites for molecular drug design.

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Amino Acid SequenceAntibodies, MonoclonalComplement C3dConsensus SequenceCrystallography, X-RayHumansHydrogen BondingLigandsModels, MolecularMolecular Sequence DataMutagenesisProtein ConformationProtein FoldingProtein Sorting SignalsProtein Structure, SecondaryProtein Structure, TertiaryReceptors, Complement 3dRecombinant ProteinsJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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G Szakonyi, J M Guthridge, D Li, K Young, V M Holers, X S Chen. 2001-06-01. Structure of complement receptor 2 in complex with its C3d ligand.. https://doi.org/10.1126/science.1059118

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