Crook Matt, Upadhyay Awani, Ido Liyana J, Hanna-Rose Wendy
Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802.
Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802
G3 (Bethesda). 2016 Nov 8;6(11):3533-3540. doi: 10.1534/g3.116.034850.
Identification of pro-cell survival signaling pathways has implications for cancer, cardiovascular, and neurodegenerative disease. We show that the epidermal growth factor receptor LET-23 (LET-23 EGFR) has a prosurvival function in counteracting excitotoxicity, and we identify novel molecular players required for this prosurvival signaling. uv1 sensory cells in the uterus undergo excitotoxic death in response to activation of the OSM-9/OCR-4 TRPV channel by the endogenous agonist nicotinamide. Activation of LET-23 EGFR can effectively prevent this excitotoxic death. We investigate the roles of signaling pathways known to act downstream of LET-23 EGFR in and find that the LET-60 Ras/MAPK pathway, but not the IP receptor pathway, is required for efficient LET-23 EGFR activity in its prosurvival function. However, activation of LET-60 Ras/MAPK pathway does not appear to be sufficient to fully mimic LET-23 EGFR activity. We screen for genes that are required for EGFR prosurvival function and uncover a role for phosphatidylcholine biosynthetic enzymes in EGFR prosurvival function. Finally, we show that exogenous application of phosphatidylcholine is sufficient to prevent some deaths in this excitotoxicity model. Our work implicates regulation of lipid synthesis downstream of EGFR in cell survival and death decisions.
确定细胞存活信号通路对癌症、心血管疾病和神经退行性疾病具有重要意义。我们发现,表皮生长因子受体LET-23(LET-23表皮生长因子受体)在对抗兴奋性毒性方面具有促存活功能,并且我们确定了这种促存活信号所需的新分子参与者。子宫中的uv1感觉细胞在内源性激动剂烟酰胺激活OSM-9/OCR-4瞬时受体电位香草酸亚家族阳离子通道4(TRPV4)后会发生兴奋性毒性死亡。激活LET-23表皮生长因子受体可以有效预防这种兴奋性毒性死亡。我们研究了已知在LET-23表皮生长因子受体下游起作用的信号通路的作用,发现LET-60 Ras/丝裂原活化蛋白激酶(MAPK)通路而非肌醇1,4,5-三磷酸受体通路是LET-23表皮生长因子受体在其促存活功能中有效发挥作用所必需的。然而,激活LET-60 Ras/MAPK通路似乎不足以完全模拟LET-23表皮生长因子受体的活性。我们筛选了表皮生长因子受体促存活功能所需的基因,并发现磷脂酰胆碱生物合成酶在表皮生长因子受体促存活功能中发挥作用。最后,我们表明外源性应用磷脂酰胆碱足以预防该兴奋性毒性模型中的一些细胞死亡。我们的工作表明表皮生长因子受体下游的脂质合成调节在细胞存活和死亡决定中起作用。