Characterization of Tyramine-Mediated Cell-Cell Communication in the Drosophila Malpighian Tubule

昆虫是最成功的一群动物，无论是从昆虫的总数还是昆虫种类的数量来看。这种成功在很大程度上要归功于它们适应各种栖息地和环境条件的能力。这种适应性的一个原因是昆虫拥有一个极其多样的排泄系统，有助于平衡水、离子和小分子的摄入和排出。在排泄系统中，尿是由一个叫做马氏小管的器官产生的。这个项目的重点是果蝇黑腹果蝇的马尔比氏小管，特别是一种小分子酪胺的能力，通过小管增加尿液的产生。提出的实验将采用马尔比氏小管功能的测量，其中特定基因的表达水平已被分子遗传技术改变。预计这样的实验将表征酪胺影响小管功能所必需的一些基因；具体来说，将鉴定酪胺合成和检测所需的基因。这些基因的鉴定不仅对更全面地了解昆虫的排泄功能，而且对酪胺被认为在昆虫的生理和行为中起作用的其他方面，如摄食和繁殖，都是很重要的。从长远来看，这种理解对于开发新的害虫控制方法可能很重要。最后，这个项目将有助于研究生和本科生的教育，他们将进行许多拟议的实验。

Insects are the most successful group of animals, both in terms of the overall number of insects and the number of insect species. This success is due, in large part, to their ability to adapt to a wide variety of habitats and environmental conditions. One reason for this adaptability is that insects possess an extremely versatile excretory system that helps balance the intake and elimination of water, ions, and small molecules. Within the excretory system, urine is produced by an organ called the Malpighian tubules. The focus of this project is the Malpighian tubules of the fruit fly Drosophila melanogaster, and specifically on the ability of a small molecule, tyramine, to increase urine production by the tubules. The proposed experiments will employ measurements of Malpighian tubule function in flies in which the expression levels of specific genes have been altered by molecular genetic techniques. It is expected that such experiments will characterize some of the genes that are necessary for tyramine to affect tubule function; specifically, the genes necessary for tyramine synthesis and detection will be identified. The identification of these genes will be important for a more complete understanding not only of insect excretory function, but also of other aspects of insect physiology and behavior in which tyramine is thought to play a role, such as feeding and reproduction. In the long term, such understanding could be important in the development of new controls for insect pest species. Finally, this project will contribute to the education of the graduate and undergraduate students who will conduct many of the proposed experiments.