Molecular optogenetic switch systems have been extensively employed as a powerful tool to spatially and temporally modulate a variety of signal transduction processes in cells. However, the applications of such systems in mechanotransduction processes where the mechanosensing proteins are subject to mechanical forces of several pN have been poorly explored. In order to apply molecular optogenetic switch systems to mechanobiological studies, it is crucial to understand their mechanical stabilities which have yet to be quantified. In this work, we quantified a frequently used molecular optogenetic switch, iLID-nano, which is an improved light-induced dimerization between LOV2-SsrA and SspB. Our results show that the iLID-nano system can withstand forces up to 10 pN for seconds to tens of seconds that decreases as force increases. The mechanical stability of the system suggests that it can be employed to modulate mechanotransduction processes that involve similar force ranges. We demonstrate the use of this system to control talin-mediated cell spreading and migration. Together, we established the physical basis for utilizing the iLID-nano system in the direct control of intramolecular force transmission in cells during mechanotransduction processes.

中文翻译：

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机械转导中的光遗传调控

分子光遗传学开关系统已被广泛用作在空间和时间上调节细胞中各种信号转导过程的强大工具。然而，这种系统在机械转导过程中机械传感蛋白受到数个pN的机械力作用的应用研究很少。为了将分子光遗传学转换系统应用于力学生物学研究，至关重要的是要了解其尚未被量化的机械稳定性。在这项工作中，我们量化了一种常用的分子光遗传学开关iLID-nano，它是LOV2-SsrA和SspB之间光诱导的二聚化的改进。我们的结果表明，iLID-nano系统可以承受高达10 pN的力达数秒至数十秒，随着力的增加而减小。该系统的机械稳定性表明它可以用于调节涉及相似力范围的机械转导过程。我们演示了使用此系统来控制塔林介导的细胞扩散和迁移。在一起，我们建立了在机械转导过程中直接控制细胞内分子力传递中利用iLID-nano系统的物理基础。