Genetic and circuit bases of mechanically-induced predator avoidance in Platynereis dumerilii larvae

逃避捕食者一直是复杂神经系统进化的主要推动力。躲避捕食者需要复杂的神经元电路来实现全身的协调控制。我们对参与躲避捕食者的完整神经元回路以及这些回路如何实现对整个生物体的控制知之甚少。我们建议使用强大的遗传学和神经科学模型--海洋环节动物Platynereis umerilii，来研究机械感觉回路在调节捕食者回避中的作用。我们将研究扁平线虫幼虫如何避免被两种蛇形捕食者--水母Clytia和Aurelia--捕食。我们将使用一种综合的方法，结合行为学、全身神经元连接学、基因敲除、钙成像和热遗传学。扁平线虫幼虫体型较小，适合通过连续切片的电子显微镜进行全身成像和连接。幼虫有典型的神经元回路，单个神经元可以用遗传工具以有针对性的方式识别和操纵。将实验生物与实验室育种培养结合使用，将使我们能够以前所未有的详细程度研究与生态相关的行为的电路基础。把全身神经元连接和电路动力学放在种间相互作用的背景下，可以更全面地理解海洋浮游动物的神经行为学和一般动物的行为。

Escape from predators has been a major driving force in the evolution of complex nervous systems. Predator avoidance requires complex neuronal circuits to achieve the coordinated control of the whole body. We have limited knowledge of complete neuronal circuits involved in predator avoidance and how these achieve control over an entire organism. We propose to use the powerful genetic and neuroscience model, the marine annelid Platynereis dumerilii, to study the function of mechanosensory circuits mediating predator avoidance. We will study how Platynereis larvae avoid predation by two cnidarian predators, the jellyfish Clytia and Aurelia. We will use an integrative approach combining behaviour, whole-body neuronal connectomics, gene knockouts, calcium imaging, and thermogenetics. Platynereis larvae are small and ideally suited for whole-body imaging and connectomics by serial sectioning electron microscopy. The larvae have stereotypical neuronal circuitry and individual neurons can be identified and manipulated in a targeted manner using genetic tools. The use of experimental organisms with laboratory breeding cultures will enable us to study the circuit bases of an ecologically relevant behaviour in unprecedented detail. Placing whole-body neuronal connectomes and circuit dynamics into the context of interspecific interactions promises a fuller understanding of the neuroethology of marine zooplankton and animal behaviour in general.