Ecdysteroid regulation of hydrocarbon biosynthesis

所有昆虫的表面都覆盖着一层很薄的长链碳氢化合物，它具有限制水分流失以防止致命的干燥的关键功能。许多物种也利用碳氢化合物进行化学通讯。尽管它们对昆虫的生存至关重要，而在大多数其他动物中却不存在，但很少有研究旨在了解碳氢化合物形成的生物化学和分子生物学。我们还需要清楚地了解昆虫的这一关键过程，以设计关键步骤的抑制剂，这些抑制剂可能在新的和无害环境的昆虫控制技术中发挥作用。家蝇（Musca domestica）是研究碳氢化合物形成的生物化学和分子生物学的优良模式昆虫。卵巢分泌的外甾体调节碳氢化合物的产生，导致雌性产生(Z)-9-三醇和一系列甲基支链碳氢化合物，所有这些都在性信息素中起作用。本文提出的工作旨在了解碳氢化合物形成的关键过程，即16和18碳脂肪酸延伸到烃类的直接前体-长链24-36碳脂肪酸。具体而言，目标是：(1)分离、克隆和测序参与碳氢化合物合成的关键酶；(2)确定这些酶在分子水平上的外甾调节；(3)测定关键酶。除了培养博士后和研究生外，本科生也将接受生物化学和分子生物学方面的培训。这项拟议的工作将有助于更好地了解昆虫的关键过程，从而为未来的害虫控制策略提供新的目标。

The surface of all insects is covered by a thin layer of very long-chain hydrocarbons that serve the critical function of restricting water loss to prevent a lethal rate of desiccation. Many species also use hydrocarbons in chemical communication. Despite their importance for an insect's survival and absence among most other animals, there have been few studies aimed at understanding the biochemistry and molecular biology of hydrocarbon formation. A clear understanding of this critical process in insects is also needed to design inhibitors of key steps that could function in novel and environmentally sound insect control techniques. The housefly, Musca domestica, is an excellent model insect with which to study the biochemistry and molecular biology of hydrocarbon formation. Ovarian produced ecdysteroids regulate hydrocarbon production, which results in the female producing (Z)-9-tricosene and a series of methyl-branched hydrocarbons, all of which function in the sex pheromone.The work proposed herein is designed to gain an understanding of a critical process in hydrocarbon formation, the elongation of 16 and 18 carbon fatty acids to the very-long chain 24-36 carbon fatty acids that are the immediate precursors to hydrocarbons. Specifically, the objectives are to: (1) Isolate, clone and sequence key enzymes involved in hydrocarbon synthesis, (2) Determine the ecdysteroid regulation of these enzymes at the molecular level and (3) Assay the key enzymes. In addition to training post-doctoral fellows and graduate students, undergraduates also will be trained in aspects of biochemistry and molecular biology. The proposed work will lead to a better understanding of critical processes in insects that could lead to new targets for future pest control strategies.