Characterization of Chemosensory Pathways in Cnidarians

刺胞动物化学感觉通路的研究。检测和响应化学刺激的能力是所有生物的基本特性，在后生动物中，专门的感觉结构（化学感觉细胞）和细胞间通路已经进化到检测和传递有关动物化学感觉环境的信息。尽管不同的生物在化学感觉通路中可能采用略有不同的机制，但对数量有限但分布广泛的群体（特别是节肢动物和脊椎动物）的研究得出的总体情况是，控制化学感觉系统的基本原理是非常相似的。然而，很少有人注意到最早的后生动物，即“第一批”具有特殊感觉细胞的动物。刺胞动物（海葵、珊瑚和水母）代表了最早的后生动物，它们是最早拥有可识别的神经系统的现存生物。因此，它们是研究早期后生动物化学感觉系统特性的理想动物，特别是确定化学感觉功能的共同机制是否适用于所有后生动物。本提案旨在通过研究水母的刺细胞这一本身既迷人又引人注目的系统，来研究刺胞动物的化学感觉传导。水母和其他刺胞动物的刺细胞或刺胞细胞对几乎同时施加的化学和机械刺激作出反应，表明潜在猎物的存在。然而，这种放电受到多种过程的严格调节，包括化学感受器和机械感受器。该提案将检查两种物种的触须中与刺胞细胞相关的化学感受器，这两种物种分别是葡萄牙人（Physalia physalis）和海荨麻（Chrysaora quinquecirrha），这两种物种至少对游泳者和渔民来说是严重的滋事者。该项目的主要目标是了解这些受体检测和转导化学刺激的机制，将信息传递给刺胞细胞，并识别和表征信息在刺胞细胞中触发的细胞事件，使它们接受随后触发放电的机械刺激。因此，该项目将获得早期生物化学感觉系统的基本信息。该项目还具有非常实用的目标，因为有关调节刺胞细胞放电的途径和机制的信息可能为抑制刺胞细胞放电的方法提供有用的见解。这些信息最终可以用于开发保护游泳者和渔民免受这些动物可能产生的痛苦和有时使其丧失功能的蜇伤的方法。该项目将通过惠特尼实验室非常活跃和成功的本科生研究经验项目，为至少一名博士后和几名本科生提供培训。该项目在招收少数族裔学生方面有着良好的记录，预计至少有一名少数族裔学生将通过该项目接受培训。

Characterization of Chemosensory Pathways in CnidariansP. Anderson, IBN 0110550ABSTRACT The ability to detect and respond to chemical stimuli is a fundamental property of all organisms, and in metazoan animals, specialized sensory structures (chemosensory cells) and intercellular pathways have evolved to detect and transmit information about the chemosensory environment of the animal. Although different organisms may employ slightly different mechanisms in chemosensory pathways, the general picture that has emerged from research with a limited number of albeit widely separated groups (particularly arthropods and vertebrates) is that the underlying principles that govern chemosensory systems are remarkably similar. However, very little attention has been paid to the earliest metazoans, the "first" animals to bear specialized sensory cells. Cnidarians (sea anemones, corals and jellyfish) represent some of the earliest metazoans, and they are the first extant organisms to possess a recognizable nervous system. Thus, they are ideal animals with which to examine the properties of early metazoan chemosensory systems and, in particular, to determine whether the common mechanisms of chemosensory function apply to all metazoans. This proposal seeks to examine chemosensory transduction in cnidarians, by studying a system that, in and of itself, is both fascinating and remarkable, the stinging cells of jellyfish. The sting cells or cnidocytes of jellyfish and other cnidarians discharge in response to near simultaneous applications of the chemical and mechanical stimuli that signal the presence of potential prey. However, this discharge is very tightly regulated by a variety of processes, including chemoreceptors and mechanoreceptors. This proposal will examine chemoreceptors associated with cnidocytes in the tentacles of two species, the Portugese Man-of-War (Physalia physalis) and sea nettle (Chrysaora quinquecirrha), two species that are, at the very least, serious nuisances for bathers and fishermen. The broad goals of this project are to understand the mechanisms used by those receptors to detect and transduce chemical stimuli, to convey that information to the cnidocytes, and identify and characterize the cellular events that information triggers in the cnidocytes, making them receptive to the subsequent mechanical stimuli that trigger discharge. As such, this project will obtain basic information about chemosensory systems in early organisms. The project also has very applied goals inasmuch as information about the pathways and mechanisms that regulate cnidocyte discharge may provide useful insights into ways to inhibit cnidocyte discharge. Such information could ultimately be used to develop ways to protect bathers and fishermen from the painful and sometimes dihabilitating stings these animals can produce. The project will provide training to at least one postdoctoral fellow, and to several undergraduates through the Whitney Laboratory's very active and successful Research Experience for Undergraduates Program. This program has an excellent record of including minorities, and at least one minority student is expected to be trained through this project.