Role of Neuronal Calcium Sensor-1 in the Cardiovascular System

Calcium (Ca2+) is an important intracellular messenger, regulating myocyte contraction via excitation-contraction (EC) coupling and gene transcription underlying hypertrophy in the heart. Although the mechanisms of EC coupling in the immature heart are believed to be different from those in the adult heart because of the structural immaturity of the sarcoplasmic reticulum in the young heart, the details of these mechanisms are not completely understood. Neuronal Ca2+ sensor-1 (NCS-1) is an EF-hand Ca2+-binding protein that is highly expressed in young hearts; however, little is known about its cardiac functions. In this review, we summarize our recent findings indicating that NCS-1 acts as a novel regulator enhancing Ca2+ signals in the heart and hence promoting contraction in the immature heart and hypertrophy in the adult heart. Possible signal transduction pathways are also discussed.