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1aly
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=1aly FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1aly OCA], [http://www.ebi.ac.uk/pdbsum/1aly PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1aly RCSB]</span> | ||
}} | }} | ||
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==Overview== | ==Overview== | ||
BACKGROUND: The CD40 ligand (CD40L) is a member of the tumor necrosis factor (TNF) family of proteins and is transiently expressed on the surface of activated T cells. The binding of CD40L to CD40, which is expressed on the surface of B cells, provides a critical and unique pathway of cellular activation resulting in antibody isotype switching, regulation of apoptosis, and B cell proliferation and differentiation. Naturally occurring mutations of CD40L result in the clinical hyper-IgM syndrome, characterized by an inability to produce immunoglobulins of the IgG, IgA and IgE isotypes. RESULTS: We have determined the crystal structure of a soluble extracellular fragment of human CD40L to 2 A resolution and with an R factor of 21.8%. Although the molecule forms a trimer similar to that found for other members of the TNF family, such as TNF alpha and lymphotoxin-alpha, and exhibits a similar overall fold, there are considerable differences in several loops including those predicted to be involved in CD40 binding. CONCLUSIONS: The structure suggests that most of the hyper-IgM syndrome mutations affect the folding and stability of the molecule rather than the CD40-binding site directly. Despite the fact that the hyper-IgM syndrome mutations are dispersed in the primary sequence, a large fraction of them are clustered in space in the vicinity of a surface loop, close to the predicted CD40-binding site. | BACKGROUND: The CD40 ligand (CD40L) is a member of the tumor necrosis factor (TNF) family of proteins and is transiently expressed on the surface of activated T cells. The binding of CD40L to CD40, which is expressed on the surface of B cells, provides a critical and unique pathway of cellular activation resulting in antibody isotype switching, regulation of apoptosis, and B cell proliferation and differentiation. Naturally occurring mutations of CD40L result in the clinical hyper-IgM syndrome, characterized by an inability to produce immunoglobulins of the IgG, IgA and IgE isotypes. RESULTS: We have determined the crystal structure of a soluble extracellular fragment of human CD40L to 2 A resolution and with an R factor of 21.8%. Although the molecule forms a trimer similar to that found for other members of the TNF family, such as TNF alpha and lymphotoxin-alpha, and exhibits a similar overall fold, there are considerable differences in several loops including those predicted to be involved in CD40 binding. CONCLUSIONS: The structure suggests that most of the hyper-IgM syndrome mutations affect the folding and stability of the molecule rather than the CD40-binding site directly. Despite the fact that the hyper-IgM syndrome mutations are dispersed in the primary sequence, a large fraction of them are clustered in space in the vicinity of a surface loop, close to the predicted CD40-binding site. | ||
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| - | ==Disease== | ||
| - | Known diseases associated with this structure: Immunodeficiency, X-linked, with hyper-IgM OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=300386 300386]], Transposition of the great arteries, dextro-looped 1 OMIM:[[http://www.ncbi.nlm.nih.gov/entrez/dispomim.cgi?id=608771 608771]] | ||
==About this Structure== | ==About this Structure== | ||
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[[Category: tnf]] | [[Category: tnf]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 18:43:00 2008'' |
Revision as of 15:43, 30 March 2008
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| , resolution 2.00Å | |||||||
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
CRYSTAL STRUCTURE OF HUMAN CD40 LIGAND
Overview
BACKGROUND: The CD40 ligand (CD40L) is a member of the tumor necrosis factor (TNF) family of proteins and is transiently expressed on the surface of activated T cells. The binding of CD40L to CD40, which is expressed on the surface of B cells, provides a critical and unique pathway of cellular activation resulting in antibody isotype switching, regulation of apoptosis, and B cell proliferation and differentiation. Naturally occurring mutations of CD40L result in the clinical hyper-IgM syndrome, characterized by an inability to produce immunoglobulins of the IgG, IgA and IgE isotypes. RESULTS: We have determined the crystal structure of a soluble extracellular fragment of human CD40L to 2 A resolution and with an R factor of 21.8%. Although the molecule forms a trimer similar to that found for other members of the TNF family, such as TNF alpha and lymphotoxin-alpha, and exhibits a similar overall fold, there are considerable differences in several loops including those predicted to be involved in CD40 binding. CONCLUSIONS: The structure suggests that most of the hyper-IgM syndrome mutations affect the folding and stability of the molecule rather than the CD40-binding site directly. Despite the fact that the hyper-IgM syndrome mutations are dispersed in the primary sequence, a large fraction of them are clustered in space in the vicinity of a surface loop, close to the predicted CD40-binding site.
About this Structure
1ALY is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
2 A crystal structure of an extracellular fragment of human CD40 ligand., Karpusas M, Hsu YM, Wang JH, Thompson J, Lederman S, Chess L, Thomas D, Structure. 1995 Oct 15;3(10):1031-9. PMID:8589998
Page seeded by OCA on Sun Mar 30 18:43:00 2008
Categories: Homo sapiens | Single protein | Hsu, Y M. | Karpusas, M. | Thomas, D. | Cd40 ligand | Cd40l | Cytokine | Hyper-igm syndrome | Tnf
