Dr. Xiaoyun Ji

Xiaoyun Ji received her PhD in Clinical Laboratory Diagnostics from Jiangsu University, where she studied “Junctophilin-2 is required for stabilizing junctin and protection against cardiomyocyte death and heart dysfunction in lipid overload-induced cardiomyopathy”. 

In her postdoc, she will further investigate the protective role of junctophilin-2 in cardiomyocytes under stress. Junctophilin-2 is required for development, maturation and integrity of the t-tubule system and the gating stability of RyR2 in cardiomyocytes. However, it remains unknown if junctophilin-2 plays a role in cardiomyocyte survival/death. Xiaoyun will investigate whether and how junctophilin-2 maintained junctin, a scaffold protein stabilizing RyR2, to prevent cardiomyocyte death under stress. The protective role of junctophilin-2 has been found in lipid overload-induced cardiomyopathy.  Other stress will be induced in cardiomyocytes by doxorubicin or hypoxia/re-oxygenation. Adenoviral vectors will be employed to manipulate expression of junctophilin-2 and junctin in cardiomyocytes. Transgenic mice over-expressing junctophilin-2 in cardiomyocytes and their littermate controls will be used to establish models. Echocardiography and molecular/cellular/biochemical analyses will be conducted. It will uncover an unappreciated role of junctophilin-2 in stabilizing junctin and preventing cardiomyocyte death under stress. Thus, junctophilin-2 and junctin may be potential therapeutic targets for cardiomyocyte survival.