Optical tools for extended neural silencing

 描述：有条件地抑制特定神经集合的活动是映射负责特定行为的电路的有效方法。虽然微生物视蛋白工具目前存在用光来沉默神经活动，但这些工具有很大的局限性，不适合需要持续沉默几分钟或几小时的应用。经典的方法是通过表达梭状芽胞杆菌神经毒素的催化轻链来实现较长时间的神经元沉默，这种轻链可以扰乱神经递质的释放，但这种方法存在时间和空间控制不佳的问题。最近的化学遗传方法，包括由设计药物(DREADD)专门激活的设计受体，已经被开发用于持续沉默，但缺乏光遗传方法的时空益处。因此，对沉默工具的需求仍然没有得到满足，这种工具结合了梭状芽胞杆菌神经毒素和化学遗传学方法的强大和持久的沉默特性，以及光遗传学的时空控制。在这里，我们将开发一种全新的工具包，用于快速、扩展的神经沉默，使用单一、简短的光脉冲，可以随时被体内系统的单光子或多光子激发激活。我们的工具不仅适用于神经递质系统，也适用于神经调节系统和神经胶质传递。这些强大的工具将补充和扩展现有的光和化学发生沉默工具集，允许使用单个光脉冲快速、稳健和持久地沉默。由于我们的策略的工作原理与当前工具完全不同，因此它可以与现有方法相结合，用于复杂的远程控制行为过程中的电路活动。

 DESCRIPTION: Conditionally silencing the activity of specific neural ensembles is a powerful approach for mapping the circuits responsible for specific behaviors. While microbial opsin tools currently exist to silence neural activity with light, these tools have significant limitations tha make them unsuitable for applications that require persistent silencing over the course of minutes or hours. Longer term neuronal silencing has been classically achieved by expressing the catalytic light chain of Clostridium neurotoxins, which disrupt neurotransmitter release, however this approach suffers from poor temporal and spatial control. Recent chemogenetic approaches, including designer receptors exclusively activated by designer drugs (DREADDs) have been developed for persistent silencing, but lack the spatiotemporal benefits of optogenetic approaches. Thus, there remains an unmet need for silencing tools that combine the robust and persistent silencing qualities of Clostridium neurotoxin and chemogenetic approaches, with the spatiotemporal control of optogenetics. Here we will develop a completely new toolkit for rapid, extended neural silencing with a single, brief light pulse that can be readiy activated by either single or multiphoton excitation for in vivo systems. Our tools will not only b applicable to neurotransmitter systems, but also to neuromodulatory systems and glial transmission. These powerful tools will complement and extend the existing opto- and chemogenetic silencing toolset by allowing rapid, robust and persistent silencing with a single light pulse. Because our strategy operates on a completely different principle than current tools, it could be multiplexed with existing approaches for complex remote control of circuit activity during behavior.