Development of insect mechanosensory neurons

检测机械信号的神经细胞对触觉、听觉、平衡和疼痛等多种感官都很重要。他们还监视身体的位置。机械敏感性离子通道在专门的神经末梢打开响应于感官刺激和离子通量通过这些通道引起膜电位的变化。这导致神经冲动沿着感觉轴突传播，神经递质从轴突末端释放，感觉信息传递到中枢神经系统。神经冲动的传播可以通过来自其他神经元的突触输入来调节。我们的研究计划旨在了解机械感觉神经元如何发育以及参与机械感觉的详细过程。我们使用的实验动物是一种大型蛾，天蛾，它经历了从卵到毛毛虫再到蛹的完全蜕变，最后成为一只成年蛾。成虫的神经发育发生在两周的蛹期，在此期间，神经系统相对容易进行实验研究，从而可以在每个发育阶段进行实验。我们研究的机械感觉神经元位于长的阑尾，触角，可以很容易地分离和用于实验，这在哺乳动物中是不可能的。我们的研究计划旨在了解感觉神经元和其他细胞之间发生的特定分子相互作用，以引导发育中的神经轴突到达大脑中的最终目的地。我们还想了解机械敏感成分的分子结构，以及将它们置于这些神经元的感觉末梢的机制。我们从这项研究中获得的知识将提供在实验上可访问的昆虫机械感觉系统的细胞和发育过程的见解。然而，许多结构和过程在脊椎动物的机械感觉器官中是相似的，这对于实验研究来说是很难接近的。

Nerve cells that detect mechanical signals are important for a wide range of senses, such as touch, hearing, balance and pain. They also monitor the position of the body. Mechanosensitive ion channels in the specialized nerve endings open in response to sensory stimuli and ion flux thorough these channels causes a change in membrane potential. This leads to propagation of nerve impulses along the sensory axon, release of neurotransmitter from the axon terminal and transfer of the sensory information to the cental nervous system. Propagation of nerve impulses can be modulated by synaptic inputs from other neurons. Our research program aims to learn how the mechanosensory neurons develop and the detailed processes involved in mechanosensation. The experimental animal we use is a large moth, Manduca sexta, that undergoes a full metamorphosis from an egg to a caterpillar to a pupa, finally emerging as an adult moth. The adult neural development occurs during the two-week pupal period, during which the nervous system is relatively easily accessible for experimental research, making it possible to perform experiments at each developmental stage. The mechanosensory neurons that we study are located in long appendices, the antennae, and can be easily isolated and used in experiments that would not be possible in mammals. Our research program aims to learn the specific molecular interactions that occur between the sensory neurons and other cells to guide the developing nerve axons to their final destinations in the brain. We also want to learn the molecular structures of the mechanosensitive components and the mechanisms involved in placing them to the sensory endings of these neurons. The knowledge that we gain from this research will offer insight in the cellular and developmental processes in an experimentally accessible insect mechanosensory system. However, many of the structures and processes are similar in vertebrate mechanosensory organs that are significantly less accessible for experimental research.