20 Years from NCX Purification and Cloning: Milestones
The Na+/Ca2+ exchanger protein was first isolated from cardiac sarcolemma in 1988 and cloned in 1990. This allowed study of Na+/Ca2+ exchange at the molecular level to begin. I will review the story leading to the cloning of NCX and the research that resulted from this event. This will include structure-function studies such as determination of the numbers of transmembrane segments and topological arrangement. Information on ion transport sites has been gathered from site-directed mutagenesis. The regions involved in Ca2+ regulation have been identified, analyzed, and crystallized.
We have also generated genetically altered mice to study the role of NCX in the myocardium. Of special interest are mice with atrial- or ventricular-specific KO of NCX that reveal new information on the role of NCX in excitation-contraction coupling and in cardiac pacemaker activity.
KeywordsNa+/Ca2+ exchange Ca2+ transport Excitation-contraction coupling Ca2+ regulation Na+ transport Cardiac pacemaking
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