Grant: CIHR-ICRH Travel Awards - ICRH / Vascular pool

The heart is made up of ~2-3 billion cells, which have unique roles in order to help the heart beat in a highly coordinated manner. Among these cells are the conduction cells, which generate and send electrical signals, providing precise cues for the muscles to beat. These cells make up the electrical network of the heart called, the conduction system. As one can imagine, defects in the conduction system can cause abnormal heart beats, and even lethal arrhythmias and sudden cardiac death. Although the conduction system was anatomically discovered more than 100 years ago, we still define the conduction system anatomically. But what exactly is it made up of at a molecular level? In my study, I have addressed this by utilizing a technique called “single-cell RNA sequencing,” which allowed me to simultaneously examine the expression levels of more than 5,000 genes in >10,000 individual cells. With this large dataset, I performed various bioinformatic analysis to reveal that the conduction system is in fact not uniform, but rather contains groups of different cells, each with a unique molecular signature. My study is the first to thoroughly track the molecular profiles of every cell in a conduction system after birth, constructing a comprehensive genetic blueprint. This discovery will not only be foundational to scientists studying the electrical function of the heart, but also be valuable to discover treatments for patients with abnormal heart rhythms resulting from defects in the conduction system.