The small GTPases Rac1 and Rap1 can fulfill multiple cellular functions because their activation kinetics and localization are precisely controlled. To probe the role of their spatio- temporal dynamics, we generated optogenetic tools that activate or inhibit endogenous Rac and Rap1 in living cells. An improved version of the light-induced dimerization (iLID) system was used to control plasma membrane localization of protein domains that specifically activate or inactivate Rap1 and Rac (Tiam1 and Chimerin for Rac, RasGRP2 and Rap1GAP for Rap1). Irradiation yielded a 50-230% increase in the concentration of these domains at the membrane, leading to effects on cell morphodynamics consistent with the known roles of Rac1 and Rap1.

中文翻译：

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使用改良的iLID系统对Rac和Rap1的光遗传抑制和激活

小型GTPases Rac1和Rap1可以实现多种细胞功能，因为它们的激活动力学和定位受到精确控制。为了探究其时空动力学的作用，我们生成了激活或抑制活细胞内源性Rac和Rap1的光遗传学工具。使用光诱导二聚化（iLID）系统的改进版本来控制质膜区域的蛋白膜定位，这些蛋白结构域特异性激活或灭活Rap1和Rac（Rac为Tiam1和Chimerin，Rap1为RasGRP2和Rap1GAP）。辐照使这些区域在膜上的浓度增加了50-230％，从而导致对细胞形态动力学的影响与Rac1和Rap1的已知作用一致。