Sodium channel dysfunction can lead to arrhythmias. A paper in the March issue of Nature Structural & Molecular Biology reports that calcium binding to a motif in the human cardiac sodium channel modulates channel gating. This may provide a molecular basis for how mutations affecting calcium binding to the motif could cause disease.
Walter Chazin and collaborators identified a calcium-binding motif called the EF-hand in the human cardiac sodium channel. They showed that this region can bind calcium directly, and that calcium binding affects the gating of the channel. An arrhythmia-causing mutation reduces calcium binding to the EF-hand and impairs the channel's gating response to calcium. These results could explain the molecular basis of some of the disease-causing mutations in the channel and suggest a potential drug target for treating arrhythmias. Author contacts: Walter J. Chazin Vanderbilt University Nashville, TN USA Tel: +1 615 936 2210 E-mail: walter.chazin@vanderbilt.edu Jeffrey R. Balser Vanderbilt University Medical Center Nashville, TN USA Tel: +1 615 936 3030 E-mail: jeff.balser@vanderbilt.edu Also available online. (C) Nature Structural & Molecular Biology press release.
Message posted by: Trevor M. D'Souza
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