Piezo1 is a mechanically activated cation channel that converts mechanical force into diverse physiological processes. Owing to its large protein size of more than 2,500 amino acids and complex 38-transmembrane helix topology, how Piezo1 is post-translationally modified for regulating its in vivo mechanotransduction functions remains largely unexplored. Here, we show that PKA activation potentiates the mechanosensitivity and slows the inactivation kinetics of mouse Piezo1 and identify the major phosphorylation site, serine-1612 (S1612), that also responds to PKC activation and shear stress. Mutating S1612 abolishes PKA and PKC regulation of Piezo1 activities. Primary endothelial cells derived from the Piezo1-S1612A knockin mice lost PKA- and PKC-dependent phosphorylation and functional potentiation of Piezo1. The mutant mice show activity-dependent elevation of blood pressure and compromised exercise endurance, resembling endothelial-specific Piezo1 knockout mice. Taken together, we identify the major PKA and PKC phosphorylation site in Piezo1 and demonstrate its contribution to Piezo1-mediated physiological functions.

中文翻译：

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Piezo1 在单个残基丝氨酸-1612 位点的磷酸化调节其机械敏感性和体内机械转导功能


Piezo1 是一种机械激活的阳离子通道，可将机械力转化为不同的生理过程。由于其超过 2,500 个氨基酸的大蛋白质大小和复杂的 38 次跨膜螺旋拓扑结构，Piezo1 如何进行翻译后修饰以调节其体内 机械转导功能在很大程度上仍未得到探索。在这里，我们表明 PKA 激活增强了小鼠 Piezo1 的机械敏感性并减慢了灭活动力学，并确定了主要的磷酸化位点丝氨酸-1612 （S1612），它也对 PKC 激活和剪切应力做出反应。突变的 S1612 消除了 Piezo1 活性的 PKA 和 PKC 调节。来自 Piezo1-S1612A 敲入小鼠的原代内皮细胞失去了 PKA 和 PKC 依赖性磷酸化和 Piezo1 的功能增强。突变小鼠表现出活动依赖性血压升高和运动耐力受损，类似于内皮特异性 Piezo1 敲除小鼠。综上所述，我们确定了 Piezo1 中的主要 PKA 和 PKC 磷酸化位点，并证明了其对 Piezo1 介导的生理功能的贡献。