Mst3在逆境下對於粒線體動態平衡及型態所扮演之角色

Abstract

Mammalian sterile20-like protein kinase 3 (Mst3)屬於GCK-type家族蛋白激酶,近來被報導指出Mst3在Staurosporine的作用下會誘使 caspase-dependent以及caspase-independent 的細胞凋亡途徑發生.且Mst3 分佈於細胞質及粒線體.為了要調查Mst3在壓力下對於粒線體動態平衡以及形態扮演的角色. 在HeLa 細胞以及 HeLa (siMst3)細胞中分別養在EBSS的培養液中 0, 2, 4, 8小時. 之後利用西方墨點法以及免疫螢光染色觀察在HeLa細胞以及HeLa (siMst3)細胞中有何不同.結果顯示Mst3調節phospho-Drp1(Ser616)以及phospho-Drp1(Ser637)這兩種不同型態的磷酸化Drp1.在粒線體型態的觀察中也有很明顯的不同,在HeLa細胞中,粒線體的型態較長且聚集在核的周圍,經過壓力的刺激,粒線體的密集程度更加集中,而在HeLa (siMst3)中粒線體則是較短的型態,但是在壓力超過4個小時,其型態變長且密集.因此Mst3對於粒線體動態平衡以及型態確實扮演重要的角色.

Mammalian sterile20-like protein kinase 3 (Mst3), a member of GCK-type Ste20-like protein kinase family, was reported recently to play important roles to trigger both caspase-dependent and –independent apoptotic pathways in response to staurosporine. Recently, Mst3 was shown to distribute in both cytoplasma and mitochondria. To investigate the role of Mst3 in mitochondria dynamics and morphology, we treat EBSS for 0, 2, 4, 8 h in HeLa,and HeLa (siMst3) cells. After treatment, by western blotting and immunostain observe the different between HeLa and HeLa (siMst3). The result indicated that Mst3 regulate different type of Drp1 (pS616) and Drp1 (pS637). The morphology of mitochondria between HeLa and HeLa (siMst3) were significant different, the HeLa cell of mitochondria morphology were longer and cluster in nucleus, after the starvation, the density of mitochondria became more closely. In the other hand, in the HeLa cell (siMst3) we observe the morphology of mitochondria more short than the HeLa cell. But when the starvation exceed 4 hours, the mitochondrial morphology became longer and closely. Mst3 really play an important role in regulating mitochondria dynamics/morphology.