Schuster Kevin, Ghysen Alain
Cold Spring Harb Protoc. 2013 Dec 1;2013(12):1172-4. doi: 10.1101/pdb.prot079467.
The lateral line is a mechanosensory system that comprises a set of discrete sense organs called neuromasts, which are arranged in reproducible patterns on the surface of fish and amphibians. The posterior component of the system, the posterior lateral line, comprises the neuromasts on the body and tail. Each neuromast has a core of mechanosensory hair cells, each of which is depolarized by water motion in one direction and hyperpolarized by motion in the other direction, thereby enabling fish to extract information from the movements of water around their body. Neuromasts are innervated by a few afferent neurons (usually two, but sometimes more), which have their cell bodies clustered in cranial ganglia and project their central axons to the hindbrain, where they extend longitudinally along all rhombomeres. Hair cells are readily labeled by small cationic styryl pyridinium dyes such as DiASP. Afferent fibers are also progressively labeled with this dye, presumably by trans-synaptic uptake. Adjusting the dye concentration and incubation time can lead to the labeling of the entire afferent system, thereby providing a fast and easy method for visualizing the central projection in the hindbrain of live fish. The simplicity of the method makes it potentially useful for screens based on forward or reverse genetic approaches. Here we present protocols for labeling hair cells in live zebrafish and for labeling afferent neurons in zebrafish embryos.
侧线是一种机械感觉系统，由一组称为神经丘的离散感觉器官组成，这些神经丘以可重复的模式排列在鱼类和两栖动物的体表。该系统的后部组件，即后侧线，包括身体和尾巴上的神经丘。每个神经丘都有一个机械感觉毛细胞核心，每个毛细胞在一个方向上被水流运动去极化，而在另一个方向上被水流运动超极化，从而使鱼类能够从其身体周围水流的运动中提取信息。神经丘由少数传入神经元（通常为两个，但有时更多）支配，这些神经元的细胞体聚集在颅神经节中，并将其中枢轴突投射到后脑，在那里它们沿着所有菱脑节纵向延伸。毛细胞很容易被小阳离子苯乙烯基吡啶染料（如DiASP）标记。传入纤维也会逐渐被这种染料标记，大概是通过跨突触摄取。调整染料浓度和孵育时间可以导致整个传入系统被标记，从而提供一种快速简便的方法来可视化活鱼后脑的中枢投射。该方法的简单性使其有可能用于基于正向或反向遗传方法的筛选。在这里，我们展示了在活斑马鱼中标记毛细胞以及在斑马鱼胚胎中标记传入神经元的方案。
