Department of Biochemistry, Boston University School of Medicine, Boston, United States.
Elife. 2020 Sep 16;9:e60155. doi: 10.7554/eLife.60155.
Heterotrimeric G-proteins are signal transducers involved in mediating the action of many natural extracellular stimuli and many therapeutic agents. Non-invasive approaches to manipulate the activity of G-proteins with high precision are crucial to understand their regulation in space and time. Here, we developed LOV2GIVe, an engineered modular protein that allows the activation of heterotrimeric G-proteins with blue light. This optogenetic construct relies on a versatile design that differs from tools previously developed for similar purposes, that is metazoan opsins, which are light-activated G-protein-coupled receptors (GPCRs). Instead, LOV2GIVe consists of the fusion of a G-protein activating peptide derived from a non-GPCR regulator of G-proteins to a small plant protein domain, such that light uncages the G-protein activating module. Targeting LOV2GIVe to cell membranes allowed for light-dependent activation of Gi proteins in different experimental systems. In summary, LOV2GIVe expands the armamentarium and versatility of tools available to manipulate heterotrimeric G-protein activity.
异三聚体 G 蛋白是信号转导因子，参与介导许多天然细胞外刺激物和许多治疗药物的作用。非侵入性方法来精确地操纵 G 蛋白的活性对于理解它们在空间和时间上的调节至关重要。在这里，我们开发了 LOV2GIVe，这是一种经过工程改造的模块化蛋白，允许用蓝光激活异三聚体 G 蛋白。这种光遗传学构建体依赖于一种通用的设计，与以前为类似目的开发的工具（即后生动物视蛋白，即光激活的 G 蛋白偶联受体（GPCR））不同。相反，LOV2GIVe 由源自非 GPCR G 蛋白调节剂的 G 蛋白激活肽与一个小的植物蛋白结构域融合而成，从而使 G 蛋白激活模块光解笼。将 LOV2GIVe 靶向质膜，可在不同的实验系统中用光依赖性激活 Gi 蛋白。总之，LOV2GIVe 扩展了用于操纵异三聚体 G 蛋白活性的工具的武器装备和多功能性。
