What powers the pumping heart?

News Brief by Isabel Smokelin

     Physiology Professor Anthony Gramolini and his colleague Professor Thomas Kislinger at the University of Toronto have made a significant discovery in studying how heart cells contract. Through using biochemical techniques, they have discovered more than 500 proteins located on the surface of cardiac contractile cells. These proteins are likely important in normal heart function and contraction. In particular, transmembrane protein 65, abbreviated as Tmem65, was found to be essential in electrical coupling and calcium signaling, two cellular communication methods. Through studying zebrafish and human stem cells, researchers have shown that Tmem65 regulates connections between adjacent cardiac contractile cells, allowing the heart muscle to contract. In addition, this particular protein is involved in helping contractile cells evolve into two functional ventricles. However, there are also 554 other similar proteins which are present among cardiac cells of mice and humans, indicating that these proteins were evolutionarily conserved, and thus important for survival. While Tmem65 was the focus of this particular study, the other proteins have potential to reveal new information about cardiac cell contraction. This research can help scientists learn about heart failure and irregular heart rhythms known as arrhythmias, aiding millions of people worldwide and significantly advancing the study of the heart.

University of Toronto. (2015, September 25). What powers the pumping heart?. ScienceDaily. Retrieved October 3, 2015 from www.sciencedaily.com/releases/2015/09/150925131425.htm