PRRT2 and cardiovascular disorder: These studies indicate that the CaSR interacts with PKC and calpain proteins, which can translocate from the membrane to the mitochondria and/or to the nucleus in I/R hearts and cardiomyocytes; however, the mechanism of the CaSR–PKC/calpain pathway in the ER–mitochondria and mitochondria–nucleus communication, and its roles in cardiovascular diseases still need further studies (Figure 1).