1j7o

From Proteopedia

Revision as of 09:59, 20 March 2008

Solution structure of Calcium-calmodulin N-terminal domain

Overview

The solution structure of Ca(2+)-ligated calmodulin is determined from residual dipolar couplings measured in a liquid crystalline medium and from a large number of heteronuclear J couplings for defining side chains. Although the C-terminal domain solution structure is similar to the X-ray crystal structure, the EF hands of the N-terminal domain are considerably less open. The substantial differences in interhelical angles correspond to negligible changes in short interproton distances and, therefore, cannot be identified by comparison of NOEs and X-ray data. NOE analysis, however, excludes a two-state equilibrium in which the closed apo conformation is partially populated in the Ca(2+)-ligated state. The difference between the crystal and solution structures of Ca(2+)-calmodulin indicates considerable backbone plasticity within the domains of calmodulin, which is key to their ability to bind a wide range of targets. In contrast, the vast majority of side chains making up the target binding surface are locked into the same chi(1) rotameric states as in complexes with target peptide.

Disease

Known diseases associated with this structure: Cavernous malformations of CNS and retina OMIM:[604214], Cerebral cavernous malformations-1 OMIM:[604214], Hyperkeratotic cutaneous capillary-venous malformations associated with cerebral capillary malformations OMIM:[604214], Leukemia, acute T-cell lymphoblastic OMIM:[603025], Leukemia, acute myeloid OMIM:[603025]

About this Structure

1J7O is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.

Reference

Solution structure of Ca(2+)-calmodulin reveals flexible hand-like properties of its domains., Chou JJ, Li S, Klee CB, Bax A, Nat Struct Biol. 2001 Nov;8(11):990-7. PMID:11685248

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