Interaction and functional consequences of HCN channels and cytosolic SAP proteins in the cardiac sinoatrial node

Heart function is regulated in large part in the upper right hand corner of the heart, where a cluster of pacemaker node cells generate the pulsatile electrical signals that spread throughout the heart muscle. These signals cause the heart to rhythmically contract and relax, leading to the smooth flowing of blood through the circulatory system. In order to send pulsatile signals and coordinate the heart’s activity, pacemaker node cells possess a unique collection of proteins. This includes ion channels, that selectively permit charged ions to cross the membrane barrier surrounding cells, generating an electric field that can be spread to surrounding cells. A distinguishing feature of the pacemaker is that it spontaneously generates these electrical impulses. Specific ion channel proteins, called HCN channels, are largely responsible for this spontaneous activity. But how and why HCN channels express as they do in these pacemaker cells is largely a mystery. Christian Peters is exploring how the functioning, or even the presence of these proteins, is affected by their interactions with accessory proteins on the interior of the cell. By developing an understanding of these interactions, his research will contribute to our knowledge of the workings of a healthy heart, and contribute to the prevention or cure of ailments associated with a malfunctioning of the myocardium, the muscular tissue of the heart.