Hou, Laasmaa et al. establish a method to correlate ryanodine receptor (RyR) nanoscale localization and function in live cardiomyocytes, by using a knock-in mouse expressing a photoactivated label on RyR2 and combining photoactivated localization microscopy to visualize RyRs and high-speed imaging to visualize the Ca2+ sparks. The number of activated RyRs within a cluster is generally low in intact cardiomyocytes and it is increased by β-adrenergic stimulation, while heart failure induces disruption of the RyR clusters and increases Ca2+ traveling sparks.
- Yufeng Hou
- Martin Laasmaa
- William E. Louch