2ic4
From Proteopedia
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|ACTIVITY= | |ACTIVITY= | ||
|GENE= CFH, HF, HF1 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 Homo sapiens]) | |GENE= CFH, HF, HF1 ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=9606 Homo sapiens]) | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY=[[1haq|1HAQ]] | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2ic4 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2ic4 OCA], [http://www.ebi.ac.uk/pdbsum/2ic4 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=2ic4 RCSB]</span> | ||
}} | }} | ||
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==Overview== | ==Overview== | ||
Factor H (FH) is a major complement control protein in serum. The seventh short complement regulator (SCR-7) domain of the 20 in FH is associated with age-related macular degeneration through a Tyr402His polymorphism. The recombinant SCR-6/8 domains containing either His402 or Tyr402 and their complexes with a heparin decasaccharide were studied by analytical ultracentrifugation and X-ray scattering. The sedimentation coefficient is concentration dependent, giving a value of 2.0 S at zero concentration and a frictional ratio f/f(o) of 1.2 for both allotypes. The His402 allotype showed a slightly greater self-association than the Tyr402 allotype, and small amounts of dimeric SCR-6/8 were found for both allotypes in 50 mM, 137 mM and 250 mM NaCl buffers. Sedimentation equilibrium data were interpreted in terms of a monomer-dimer equilibrium with a dissociation constant of 40 microM for the His402 form. The Guinier radius of gyration R(G) of 3.1-3.3 nm and the R(G)/R(O) ratio of 2.0-2.1 showed that SCR-6/8 is relatively extended in solution. The distance distribution function P(r) showed a maximum dimension of 10 nm, which is less than the length expected for a linear domain arrangement. The constrained scattering and sedimentation modelling of FH SCR-6/8 showed that bent SCR arrangements fit the data better than linear arrangements. Previously identified heparin-binding residues were exposed on the outside curvature of this bent domain structure. Heparin caused the formation of a more linear structure, possibly by binding to residues in the linker. It was concluded that the His402 allotype may self-associate more readily than the Tyr402 allotype, SCR-6/8 is partly responsible for the folded-back structure of intact FH, and SCR-6/8 changes conformation upon heparin binding. | Factor H (FH) is a major complement control protein in serum. The seventh short complement regulator (SCR-7) domain of the 20 in FH is associated with age-related macular degeneration through a Tyr402His polymorphism. The recombinant SCR-6/8 domains containing either His402 or Tyr402 and their complexes with a heparin decasaccharide were studied by analytical ultracentrifugation and X-ray scattering. The sedimentation coefficient is concentration dependent, giving a value of 2.0 S at zero concentration and a frictional ratio f/f(o) of 1.2 for both allotypes. The His402 allotype showed a slightly greater self-association than the Tyr402 allotype, and small amounts of dimeric SCR-6/8 were found for both allotypes in 50 mM, 137 mM and 250 mM NaCl buffers. Sedimentation equilibrium data were interpreted in terms of a monomer-dimer equilibrium with a dissociation constant of 40 microM for the His402 form. The Guinier radius of gyration R(G) of 3.1-3.3 nm and the R(G)/R(O) ratio of 2.0-2.1 showed that SCR-6/8 is relatively extended in solution. The distance distribution function P(r) showed a maximum dimension of 10 nm, which is less than the length expected for a linear domain arrangement. The constrained scattering and sedimentation modelling of FH SCR-6/8 showed that bent SCR arrangements fit the data better than linear arrangements. Previously identified heparin-binding residues were exposed on the outside curvature of this bent domain structure. Heparin caused the formation of a more linear structure, possibly by binding to residues in the linker. It was concluded that the His402 allotype may self-associate more readily than the Tyr402 allotype, SCR-6/8 is partly responsible for the folded-back structure of intact FH, and SCR-6/8 changes conformation upon heparin binding. | ||
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| - | ==Disease== | ||
| - | Known diseases associated with this structure: Complement factor H deficiency OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=134370 134370]], Factor H and factor H-like 1 OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=134370 134370]], Hemolytic-uremic syndrome OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=134370 134370]], Macular degeneration, age-related, 4 OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=134370 134370]], Membranoproliferative glomerulonephritis with CFH deficiency OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=134370 134370]] | ||
==About this Structure== | ==About this Structure== | ||
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[[Category: x-ray scattering]] | [[Category: x-ray scattering]] | ||
| - | ''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 03:42:18 2008'' |
Revision as of 00:42, 31 March 2008
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| Gene: | CFH, HF, HF1 (Homo sapiens) | ||||||
| Related: | 1HAQ
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
Solution structure of the His402 allotype of the Factor H SCR6-SCR7-SCR8 fragment
Overview
Factor H (FH) is a major complement control protein in serum. The seventh short complement regulator (SCR-7) domain of the 20 in FH is associated with age-related macular degeneration through a Tyr402His polymorphism. The recombinant SCR-6/8 domains containing either His402 or Tyr402 and their complexes with a heparin decasaccharide were studied by analytical ultracentrifugation and X-ray scattering. The sedimentation coefficient is concentration dependent, giving a value of 2.0 S at zero concentration and a frictional ratio f/f(o) of 1.2 for both allotypes. The His402 allotype showed a slightly greater self-association than the Tyr402 allotype, and small amounts of dimeric SCR-6/8 were found for both allotypes in 50 mM, 137 mM and 250 mM NaCl buffers. Sedimentation equilibrium data were interpreted in terms of a monomer-dimer equilibrium with a dissociation constant of 40 microM for the His402 form. The Guinier radius of gyration R(G) of 3.1-3.3 nm and the R(G)/R(O) ratio of 2.0-2.1 showed that SCR-6/8 is relatively extended in solution. The distance distribution function P(r) showed a maximum dimension of 10 nm, which is less than the length expected for a linear domain arrangement. The constrained scattering and sedimentation modelling of FH SCR-6/8 showed that bent SCR arrangements fit the data better than linear arrangements. Previously identified heparin-binding residues were exposed on the outside curvature of this bent domain structure. Heparin caused the formation of a more linear structure, possibly by binding to residues in the linker. It was concluded that the His402 allotype may self-associate more readily than the Tyr402 allotype, SCR-6/8 is partly responsible for the folded-back structure of intact FH, and SCR-6/8 changes conformation upon heparin binding.
About this Structure
2IC4 is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Associative and structural properties of the region of complement factor H encompassing the Tyr402His disease-related polymorphism and its interactions with heparin., Fernando AN, Furtado PB, Clark SJ, Gilbert HE, Day AJ, Sim RB, Perkins SJ, J Mol Biol. 2007 Apr 27;368(2):564-81. Epub 2007 Feb 22. PMID:17362990
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