Schenk Laura K, Schulze Ulf, Henke Sebastian, Weide Thomas, Pavenstädt Hermann
Cell Physiol Biochem. 2016;38(6):2452-63. doi: 10.1159/000445596. Epub 2016 Jun 13.
Background / Aims: TMEM16F is a transmembrane protein from a conserved family of Ca2+-activated proteins, which is highly expressed in several tissues. TMEM16F confers phospholipid scramblase activity and Ca2+-activated electrolyte channel activity. Potentially thereby, TMEM16F is involved in cell cycle control and apoptotic signaling. The present study evaluated the role of TMEM16F on cell proliferation and viability in Human Embryonic Kidney cells.
An inducible knockdown of TMEM16F was generated and markers of apoptosis and proliferation were assessed via flow cytometry, western blotting and MTT uptake assay under different conditions.
TMEM16F knockdown resulted in attenuated growth of HEK293 cells. This observation correlated with an increased phosphatidylserine exposure and a decreased fraction of viable cells. Interestingly, the cells were not sensitized to Staurosporine- induced cell death. Western blot analyses displayed a parallel activation of pro- and antiapoptotic signaling pathways: Caspase 3 cleavage and Cyclin D1 abundance were simultaneously increased. Furthermore, knockdown of TMEM16F led to activation of AKT signaling.
TMEM16F modifies viability of Human Embryonic Kidney cells via its function as a phospholipid scramblase and activation of AKT signaling pathways.
背景/目的：TMEM16F是一种来自保守的钙激活蛋白家族的跨膜蛋白，在多种组织中高表达。TMEM16F具有磷脂翻转酶活性和钙激活电解质通道活性。因此，TMEM16F可能参与细胞周期调控和凋亡信号传导。本研究评估了TMEM16F在人胚肾细胞中对细胞增殖和活力的作用。
构建了可诱导的TMEM16F敲低模型，并在不同条件下通过流式细胞术、蛋白质免疫印迹和MTT摄取试验评估凋亡和增殖标志物。
TMEM16F敲低导致HEK293细胞生长减弱。这一观察结果与磷脂酰丝氨酸暴露增加和活细胞比例降低相关。有趣的是，细胞对星形孢菌素诱导的细胞死亡不敏感。蛋白质免疫印迹分析显示促凋亡和抗凋亡信号通路同时激活：半胱天冬酶3切割和细胞周期蛋白D1丰度同时增加。此外，TMEM16F敲低导致AKT信号通路激活。
TMEM16F通过其作为磷脂翻转酶的功能和AKT信号通路的激活来改变人胚肾细胞的活力。
