2cm5
From Proteopedia
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==Overview== | ==Overview== | ||
| - | The Ca(2+) binding properties of C2 domains are essential for the function | + | The Ca(2+) binding properties of C2 domains are essential for the function of their host proteins. We present here the first crystal structures showing an unexpected Ca(2+) binding mode of the C2B domain of rabphilin-3A in atomic detail. Acidic residues from the linker region between the C2A and C2B domains of rabphilin-3A interact with the Ca(2+)-binding region of the C2B domain. Because of these interactions, the coordination sphere of the two bound Ca(2+) ions is almost complete. Mutation of these acidic residues to alanine resulted in a 10-fold decrease in the intrinsic Ca(2+) binding affinity of the C2B domain. Using NMR spectroscopy, we show that this interaction occurred only in the Ca(2+)-bound state of the C2B domain. In addition, this Ca(2+) binding mode was maintained in the C2 domain tandem fragment. In NMR-based liposome binding assays, the linker was not released upon phospholipid binding. Therefore, this unprecedented Ca(2+) binding mode not only shows how a C2 domain increases its intrinsic Ca(2+) affinity, but also provides the structural base for an atypical protein-Ca(2+)-phospholipid binding mode of rabphilin-3A. |
==About this Structure== | ==About this Structure== | ||
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[[Category: Montaville, P.]] | [[Category: Montaville, P.]] | ||
[[Category: Schlicker, C.]] | [[Category: Schlicker, C.]] | ||
| - | [[Category: Sheldrick, G | + | [[Category: Sheldrick, G M.]] |
[[Category: CA]] | [[Category: CA]] | ||
[[Category: c2 domain]] | [[Category: c2 domain]] | ||
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[[Category: zinc-finger]] | [[Category: zinc-finger]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:50:12 2008'' |
Revision as of 14:50, 21 February 2008
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CRYSTAL STRUCTURE OF THE C2B DOMAIN OF RABPHILIN
Overview
The Ca(2+) binding properties of C2 domains are essential for the function of their host proteins. We present here the first crystal structures showing an unexpected Ca(2+) binding mode of the C2B domain of rabphilin-3A in atomic detail. Acidic residues from the linker region between the C2A and C2B domains of rabphilin-3A interact with the Ca(2+)-binding region of the C2B domain. Because of these interactions, the coordination sphere of the two bound Ca(2+) ions is almost complete. Mutation of these acidic residues to alanine resulted in a 10-fold decrease in the intrinsic Ca(2+) binding affinity of the C2B domain. Using NMR spectroscopy, we show that this interaction occurred only in the Ca(2+)-bound state of the C2B domain. In addition, this Ca(2+) binding mode was maintained in the C2 domain tandem fragment. In NMR-based liposome binding assays, the linker was not released upon phospholipid binding. Therefore, this unprecedented Ca(2+) binding mode not only shows how a C2 domain increases its intrinsic Ca(2+) affinity, but also provides the structural base for an atypical protein-Ca(2+)-phospholipid binding mode of rabphilin-3A.
About this Structure
2CM5 is a Single protein structure of sequence from Rattus norvegicus with as ligand. Known structural/functional Site: . Full crystallographic information is available from OCA.
Reference
The C2A-C2B linker defines the high affinity Ca(2+) binding mode of rabphilin-3A., Montaville P, Schlicker C, Leonov A, Zweckstetter M, Sheldrick GM, Becker S, J Biol Chem. 2007 Feb 16;282(7):5015-25. Epub 2006 Dec 13. PMID:17166855
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