斯芬戈辛-1-酸盐通过Gβγ信号传递激活LRRC8体积调节的离子通道
Yulia Kostritskaia1, Sumaira Pervaiz2, Anna Klemmer1
1Institute for Molecular Medicine, MSH Medical School Hamburg, Hamburg, Germany.
The Journal of physiology
|November 4, 2024
概括
斯芬哥辛-1-酸盐 (S1P) 通过S1PR1和Gβγ-PLCβ信号,激活含有白蛋白的重复8 (LRRC8) 通道. 这一途径与透性胀不同,揭示了LRRC8/VRAC激活的关键机制.
科学领域:
- 细胞生理学 细胞生理学
- 分子生物学分子生物学
- 离子通道功能的功能
背景情况:
- 含有8个 (LRRC8) 蛋白质的氨酸丰富的重复蛋白形成体积调节的离子通道 (VRAC),对细胞体积调节,膜潜力和谷氨酸释放至关重要.
- 由于它们对药物的透性,LRRC8/VRACs是治疗标,但它们的激活机制超出了透性胀仍然不清楚.
- 斯芬戈辛-1-酸盐 (S1P) 是一种已知可以激活某些细胞类型中的LRRC8/VRAC的信号脂质,但根本途径尚未完全阐明.
研究的目的:
- 研究S1P诱导LRRC8/VRACs激活的机制.
- 确定G蛋白合受体 (GPCR) 和下游信号通路在S1P介导的通道激活中的参与.
- 为了比较S1P诱导的激活与低压诱导的激活路径.
主要方法:
- 跨子单位的Förster共振能量传输 (FRET) 测量,以监测LRRC8通道活动.
- 全细胞补丁电生理学记录LRRC8/VRAC电流.
- 药理学调制和基因枯竭细胞,以评估特定GPCR和G蛋白 (Gαi,Gαq,Gβγ) 和信号分子 (PLCβ,PKD) 的作用.
主要成果:
- S1P通过HeLa细胞中的S1P受体1 (S1PR1) 激活LRRC8/VRACs.
- 不是Gαi或Gαq的Gβγ二聚体对S1P诱导的LRRC8/VRAC激活至关重要,它会招募脂酶Cβ (PLCβ).
- 由S1P诱导的激活涉及蛋白激酶D (PKD) 酸化,这种途径可以通过HEK293细胞中的PLCβ过度表达来促进.
结论:
- 通过S1PR1介导的Gβγ-PLCβ信号传递是S1P对同位素LRRC8/VRAC激活的关键机制.
- 该研究确定了一种特定的信号级联,涉及S1P介导通道激活中的Gβγ二聚体和PLCβ.
- 无论是S1P诱导的还是低压诱导的LRRC8/VRAC激活,都会汇聚到蛋白激酶D激活上.
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