2fcb
From Proteopedia
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|ACTIVITY= | |ACTIVITY= | ||
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY= | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2fcb FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2fcb OCA], [http://www.ebi.ac.uk/pdbsum/2fcb PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=2fcb RCSB]</span> | ||
}} | }} | ||
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==Overview== | ==Overview== | ||
Fcgamma-receptors (FcgammaRs) represent the link between the humoral and cellular immune responses. Via the binding to FcgammaR-positive cells, immunocomplexes trigger several functions such as endocytosis, antibody-dependent cell-mediated cytotoxity (ADCC) and the release of mediators, making them a valuable target for the modulation of the immune system. We solved the crystal structure of the soluble human Fcgamma-receptor IIb (sFcgammaRIIb) to 1.7 A resolution. The structure reveals two typical immunoglobulin (Ig)-like domains enclosing an angle of approximately 70 degrees, leading to a heart-shaped overall structure. In contrast to the observed flexible arrangement of the domains in other members of the Ig superfamily, the two domains are anchored by several hydrogen bonds. The structure reveals that the residues relevant for IgG binding, which were already partially characterized by mutagenesis studies, are located within the BC, C'E and FG loops between the beta-strands of the second domain. Moreover, we discuss a model for the sFcgammaRIIb:IgG complex. In this model, two FcgammaR molecules bind one IgG molecule with their second domains, while the first domain points away from the complex and is therefore available for binding other cell surface molecules, by which potential immunosuppressing functions could be mediated. | Fcgamma-receptors (FcgammaRs) represent the link between the humoral and cellular immune responses. Via the binding to FcgammaR-positive cells, immunocomplexes trigger several functions such as endocytosis, antibody-dependent cell-mediated cytotoxity (ADCC) and the release of mediators, making them a valuable target for the modulation of the immune system. We solved the crystal structure of the soluble human Fcgamma-receptor IIb (sFcgammaRIIb) to 1.7 A resolution. The structure reveals two typical immunoglobulin (Ig)-like domains enclosing an angle of approximately 70 degrees, leading to a heart-shaped overall structure. In contrast to the observed flexible arrangement of the domains in other members of the Ig superfamily, the two domains are anchored by several hydrogen bonds. The structure reveals that the residues relevant for IgG binding, which were already partially characterized by mutagenesis studies, are located within the BC, C'E and FG loops between the beta-strands of the second domain. Moreover, we discuss a model for the sFcgammaRIIb:IgG complex. In this model, two FcgammaR molecules bind one IgG molecule with their second domains, while the first domain points away from the complex and is therefore available for binding other cell surface molecules, by which potential immunosuppressing functions could be mediated. | ||
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| - | ==Disease== | ||
| - | Known diseases associated with this structure: Lupus nephritis, susceptibility to OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=146790 146790]], Malaria, resistance to OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=604590 604590]], Systemic lupus erythematosus, susceptibility to OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=604590 604590]] | ||
==About this Structure== | ==About this Structure== | ||
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[[Category: receptor]] | [[Category: receptor]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Mon Mar 31 03:00:48 2008'' |
Revision as of 00:00, 31 March 2008
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| , resolution 1.74Å | |||||||
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
HUMAN FC GAMMA RECEPTOR IIB ECTODOMAIN (CD32)
Overview
Fcgamma-receptors (FcgammaRs) represent the link between the humoral and cellular immune responses. Via the binding to FcgammaR-positive cells, immunocomplexes trigger several functions such as endocytosis, antibody-dependent cell-mediated cytotoxity (ADCC) and the release of mediators, making them a valuable target for the modulation of the immune system. We solved the crystal structure of the soluble human Fcgamma-receptor IIb (sFcgammaRIIb) to 1.7 A resolution. The structure reveals two typical immunoglobulin (Ig)-like domains enclosing an angle of approximately 70 degrees, leading to a heart-shaped overall structure. In contrast to the observed flexible arrangement of the domains in other members of the Ig superfamily, the two domains are anchored by several hydrogen bonds. The structure reveals that the residues relevant for IgG binding, which were already partially characterized by mutagenesis studies, are located within the BC, C'E and FG loops between the beta-strands of the second domain. Moreover, we discuss a model for the sFcgammaRIIb:IgG complex. In this model, two FcgammaR molecules bind one IgG molecule with their second domains, while the first domain points away from the complex and is therefore available for binding other cell surface molecules, by which potential immunosuppressing functions could be mediated.
About this Structure
2FCB is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Crystal structure of the soluble form of the human fcgamma-receptor IIb: a new member of the immunoglobulin superfamily at 1.7 A resolution., Sondermann P, Huber R, Jacob U, EMBO J. 1999 Mar 1;18(5):1095-103. PMID:10064577
Page seeded by OCA on Mon Mar 31 03:00:48 2008
Categories: Homo sapiens | Single protein | Huber, R. | Jacob, U. | Sondermann, P. | Cd32 | Fc | Receptor
