title: Structure of complement receptor 2 in complex with its C3d ligand.
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.
authors.affiliation: Department of Biochemistry and Molecular Genetics, University of Colorado Health Science Center, School of Medicine, Denver, CO 80262, USA.
authors.forename: G
authors.initials: G
authors.lastname: Szakonyi
authors.forename: J M
authors.initials: JM
authors.lastname: Guthridge
authors.forename: D
authors.initials: D
authors.lastname: Li
authors.forename: K
authors.initials: K
authors.lastname: Young
authors.forename: V M
authors.initials: VM
authors.lastname: Holers
authors.forename: X S
authors.initials: XS
authors.lastname: Chen
mesh_terms: D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal; D015933:Complement C3d / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D016384:Consensus Sequence; D018360:Crystallography, X-Ray; D006801:Humans; D006860:Hydrogen Bonding; D008024:Ligands; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016296:Mutagenesis; D011487:Protein Conformation; D017510:Protein Folding; D021382:Protein Sorting Signals; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D017464:Receptors, Complement 3d / Q000737:chemistry* / Q000276:immunology / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism
chemical_list: D000911:Antibodies, Monoclonal; D008024:Ligands; D021382:Protein Sorting Signals; D017464:Receptors, Complement 3d; D011994:Recombinant Proteins; D015933:Complement C3d