What controls how heart muscle cells contract?

Functional assessment of cardiac ryanodine receptor Ca2+ release channel populations: A direct demonstration of coupled gating?

Dr Nia Lowri Thomas and her team at Cardiff University are studying the processes that control how heart muscle cells contract during each heartbeat and what goes wrong in abnormal heart rhythms. For heart muscle cells to contract, calcium must be released quickly from an internal store in the cell. This calcium is released through lots of protein channels called RyR2 receptors, and scientists think these channels link together in a group and open and close in unison. They think this enables each contraction to happen in a quick and organised fashion, and if it doesn’t it can lead to an abnormal heart rhythm. But we don’t know whether, or how, the channels link and open and close together, and we cannot currently study them in detail. Dr Thomas has developed a new experimental imaging technique to directly study these channels. In this project, she will use it to see whether RyR2 channels are next to one another and whether channels packed close together open and close at the same time. Dr Thomas will then test what could influence this simultaneous opening and closing to see which are important in generating arrhythmias. This research will shed new light on how RyR2 channels open and close, and if they are linked to abnormal heart rhythms.