2cm5
From Proteopedia
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==Overview== | ==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 .. | + | 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== | ||
| - | 2CM5 is a | + | 2CM5 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Rattus_norvegicus Rattus norvegicus] with CA as [http://en.wikipedia.org/wiki/ligand ligand]. Structure known Active Site: AC1. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=2CM5 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: zinc-finger]] | [[Category: zinc-finger]] | ||
| - | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Mon Nov 5 14:29:47 2007'' |
Revision as of 12:24, 5 November 2007
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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 CA as ligand. Structure known Active Site: AC1. 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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