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.
Walter J. Chazin
Tel: +1 615 936 2210
Jeffrey R. Balser
Vanderbilt University Medical Center
Tel: +1 615 936 3030
Also available online.
(C) Nature Structural & Molecular Biology press release.
Message posted by: Trevor M. D'Souza