| Structural highlights
1w2s is a 2 chain structure with sequence from Homo sapiens. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
| | Related: | 1c3d, 1ghq, 1ly2 |
| Resources: | FirstGlance, OCA, RCSB, PDBsum |
Disease
[CR2_HUMAN] Genetic variations in CR2 are associated with susceptibility to systemic lupus erythematosus type 9 (SLEB9) [MIM:610927]. Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with a complex genetic basis. SLE is an inflammatory, and often febrile multisystemic disorder of connective tissue characterized principally by involvement of the skin, joints, kidneys, and serosal membranes. It is thought to represent a failure of the regulatory mechanisms of the autoimmune system.[1] Defects in CR2 are the cause of immunodeficiency, common variable, type 7 (CVID7) [MIM:614699]. A primary immunodeficiency characterized by antibody deficiency, hypogammaglobulinemia, recurrent bacterial infections and an inability to mount an antibody response to antigen. The defect results from a failure of B-cell differentiation and impaired secretion of immunoglobulins; the numbers of circulating B cells is usually in the normal range, but can be low.[2]
Function
[CR2_HUMAN] Receptor for complement C3Dd, for the Epstein-Barr virus on human B-cells and T-cells and for HNRPU. Participates in B lymphocytes activation.[3]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Complement receptor type 2 (CR2, CD21) forms a tight complex with C3d, a fragment of C3, the major complement component. Previous crystal structures of the C3d-CR2 SCR 1-2 complex and free CR2 SCR 1-2 showed that the two SCR domains of CR2 form contact with each other in a closed V-shaped structure. SCR 1 and SCR 2 are connected by an unusually long eight-residue linker peptide. Medium-resolution solution structures for CR2 SCR 1-2, C3d, and their complex were determined by X-ray scattering and analytical ultracentrifugation. CR2 SCR 1-2 is monomeric. For CR2 SCR 1-2, its radius of gyration R(G) of 2.12(+/-0.05) nm, its maximum length of 10nm and its sedimentation coefficient s20,w(o) of 1.40(+/-0.03) S do not agree with those calculated from the crystal structures, and instead suggest an open structure. Computer modelling of the CR2 SCR1-2 solution structure was based on the structural randomisation of the eight-residue linker peptide joining SCR 1 and SCR 2 to give 9950 trial models. Comparisons with the X-ray scattering curve indicated that the most favoured arrangements for the two SCR domains corresponded to an open V-shaped structure with no contacts between the SCR domains. For C3d, X-ray scattering and sedimentation velocity experiments showed that it exists as a monomer-dimer equilibrium with a dissociation constant of 40 microM. The X-ray scattering curve for monomeric C3d gave an R(G) value of 1.95 nm, and this together with its s20,w(o) value of 3.17 S gave good agreement with the monomeric C3d crystal structure. Modelling of the C3d dimer gave good agreements with its scattering and ultracentrifugation parameters. For the complex, scattering and ultracentrifugation experiments showed that there was no dimerisation, indicating that the C3d dimerisation site was located close to the CR2 SCR 1-2 binding site. The R(G) value of 2.44(+/-0.1) nm, its length of 9 nm and its s20,w(o) value of 3.45(+/-0.01) S showed that its structure was not much more elongated than that of C3d. Calculations with 9950 models of CR2 SCR 1-2 bound to C3d through SCR 2 showed that SCR 1 formed an open V-shaped structure with SCR 2 and was capable of interacting with the surface of C3d. We conclude that the open V-shaped structures formed by CR2 SCR 1-2, both when free and when bound to C3d, are optimal for the formation of a tight two-domain interaction with its ligand C3d.
Solution structure of the complex between CR2 SCR 1-2 and C3d of human complement: an X-ray scattering and sedimentation modelling study.,Gilbert HE, Eaton JT, Hannan JP, Holers VM, Perkins SJ J Mol Biol. 2005 Feb 25;346(3):859-73. Epub 2005 Jan 12. PMID:15713468[4]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Wu H, Boackle SA, Hanvivadhanakul P, Ulgiati D, Grossman JM, Lee Y, Shen N, Abraham LJ, Mercer TR, Park E, Hebert LA, Rovin BH, Birmingham DJ, Chang DM, Chen CJ, McCurdy D, Badsha HM, Thong BY, Chng HH, Arnett FC, Wallace DJ, Yu CY, Hahn BH, Cantor RM, Tsao BP. Association of a common complement receptor 2 haplotype with increased risk of systemic lupus erythematosus. Proc Natl Acad Sci U S A. 2007 Mar 6;104(10):3961-6. Epub 2007 Feb 22. PMID:17360460 doi:0609101104
- ↑ Thiel J, Kimmig L, Salzer U, Grudzien M, Lebrecht D, Hagena T, Draeger R, Volxen N, Bergbreiter A, Jennings S, Gutenberger S, Aichem A, Illges H, Hannan JP, Kienzler AK, Rizzi M, Eibel H, Peter HH, Warnatz K, Grimbacher B, Rump JA, Schlesier M. Genetic CD21 deficiency is associated with hypogammaglobulinemia. J Allergy Clin Immunol. 2012 Mar;129(3):801-810.e6. doi:, 10.1016/j.jaci.2011.09.027. Epub 2011 Oct 27. PMID:22035880 doi:10.1016/j.jaci.2011.09.027
- ↑ Barel M, Balbo M, Gauffre A, Frade R. Binding sites of the Epstein-Barr virus and C3d receptor (CR2, CD21) for its three intracellular ligands, the p53 anti-oncoprotein, the p68 calcium binding protein and the nuclear p120 ribonucleoprotein. Mol Immunol. 1995 Apr;32(6):389-97. PMID:7753047
- ↑ Gilbert HE, Eaton JT, Hannan JP, Holers VM, Perkins SJ. Solution structure of the complex between CR2 SCR 1-2 and C3d of human complement: an X-ray scattering and sedimentation modelling study. J Mol Biol. 2005 Feb 25;346(3):859-73. Epub 2005 Jan 12. PMID:15713468 doi:10.1016/j.jmb.2004.12.006
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