Characterization of a Water-Borne Egg-Laying Synchronization Pheromone

海洋环境中的肽信息素通信是一种古老的化学通信形式。在加利福尼亚海蜗牛中，产卵个体分泌一种肽信息素引诱剂（“吸引”），将其他海蜗牛吸引到信息素的来源，从而形成交配和产卵聚集。引人注目的是，加利福尼亚海百合也吸引了其他海百合种类的成员。在5个不同种类的小灰杉的吸引序列中发现了7个氨基酸的保守延伸，表明该区域对活性很重要。这项研究的一个主要目标是确定这个区域是否对吸引力活动至关重要。这将通过以下方式实现：1)测试保守区带电残基发生突变的突变吸引子；2)合成和测试与引力守恒区相对应的肽。第二个目标是纯化，表征，克隆和表达第二种候选信息素，该信息素是在海兔产卵期间分泌的。将积极产蛋的海兔放在有非产蛋海兔的水族箱中，非产蛋动物的产蛋频率更高，这表明卵层分泌了一种产蛋同步信息素。候选信息素将从卵带洗脱液中纯化，进行化学表征、克隆和重组信息素测试，以确定其是否触发神经内分泌袋细胞释放产卵激素到血液中以刺激卵子释放。这项研究的结果将对研究水生环境中化学通讯、肽信息素和生殖行为调节的研究人员感兴趣。它们将提供有关吸引家族及其受体的重要信息，并将为嗅觉系统的研究打开大门。本研究还将为博士后、研究生、本科生和高中生提供教育和培训机会。

Peptide pheromonal communication in the marine environment is an ancient form of chemical communication. In the marine snail Aplysia californica, egg-laying individuals secrete a peptide pheromonal attractant ("attractin") that attracts other Aplysia to the source of the pheromone, resulting in the formation of mating and egg-laying aggregations. Strikingly, Aplysia californica attractin also attracts members of other Aplysia species as well. A conserved stretch of 7 amino acids is found in the attractin sequences of five different species of Aplysia, suggesting that this region is important for activity. One major goal of this study is to determine whether this region is critical for attraction activity. This will be accomplished by: 1) testing mutant attractins in which charged residues in the conserved region are mutated; and 2) synthesizing and testing peptides corresponding to conserved regions of attractin. A second goal is to purify, characterize, clone, and express a second candidate pheromone that is secreted during Aplysia egg laying. When an actively egg-laying Aplysia is placed in an aquarium containing non-laying Aplysia, a higher frequency of egg-laying occurs among non-laying animals, suggesting that an egg-laying synchronization pheromone is secreted by egg layers. The candidate pheromone will be purified from eluates of egg cordons, chemically characterized, cloned, and recombinant pheromone tested to determine whether it triggers the neuroendocrine bag cells to release egg-laying hormone into the blood to stimulate egg release. The results of this study will be of interest to investigators working on chemical communication, peptide pheromones, and the regulation of reproductive behavior in the aquatic environment. They will provide important information about the attractin family and their receptors, and will open the door to studies of the olfactory system. This research will also provide educational and training opportunities for postdoctoral, graduate, undergraduate, and high school students.