2007-08-012024-05-17https://scholars.lib.ntu.edu.tw/handle/123456789/685595摘要：圍食膜是大部分昆蟲消化道中的一層膜狀構造，包覆著昆蟲攝食進入腸道的食物團，而後於消化過程中隨著食物團塊，往後腸方向移動，最後隨著未能消化的殘渣形成糞便，排出體外；因此，昆蟲需投注相當多的能量與資源於圍食膜構造之形成與維持。圍食膜由幾丁質與蛋白質成份組成，具有促進昆蟲消化及保護昆蟲腸道上皮細胞之重要功能，此一重要之功能也使得圍食膜成為害蟲防治的有效標的。小菜蛾由於其繁殖力強、世代短、可適應各種不同環境，使其成為十字花科植物世界性之害蟲，然而目前卻無其圍食膜相關之研究。本計畫之目的在解析小菜蛾之超微細構造，並利用蛋白質體學技術鑑定小菜蛾圍食膜之組成蛋白，以作為訂定害蟲防治策略之依據。 本計畫於第一年預計完成 (一)以電子顯微鏡技術解析小菜蛾圍食膜之超微結構，(二)以蛋白質體學技術鑑定小菜蛾圍食膜之蛋白質組成份，(三)運用生物資訊方法，解析圍食膜蛋白之結構及其與幾丁質結合之作用；計畫第二年目標為(一)選殖及表現小菜蛾之幾丁質&#37238;(chitinase)及幾丁質合成酵素(chitin synthesis)，(二)研究小菜蛾幾丁質生合成之調控機制，(三)幾丁質合成於小菜蛾圍食膜形成過程之角色。計畫第三年目標為(一)幾丁質&#37238;(chitinase)及幾丁質合成酵素(chitin synthesis)之過量表現對小菜蛾之毒性作用，(二)發展以小菜蛾圍食膜為標的之生物殺蟲劑。經由本計畫之研究可以直接解析小菜蛾圍食膜之構造及其組成份，對於發展以圍食膜為標的之生物防治策略也是不可或缺的。 <br> Abstract: Peritrophic membrane (PM) is a membranous film lines the digestive tract of most insects to surrounding the ingested food bolus. The PM move poesteriorly with the food bolus along the digestive canal, and eventually excreted in accompany with larval fecal pellets. Therefore, insects invest a significant amount of energy and resource to produce and maintain the PM. The PM is composed of chitin and proteins and plays important roles in facilitating food digestion and providing protection to the gut epithelium. The important physiological functions of PM suggest that PM can be a significant structural target for insect control. Plutella xylostella, with its high reproductive potential, short generation time and characteristics adaptive to adverse envrionemts, has become one of the most serious pest of cruciferous plants worldwide, however, there is no information available regarding its PM formation and molecular structure. The purpose of this project is to dissect the ultrastructure of PM and to systematic identification of PM proteins by proteomic approach in P. xylostella. These projects aim to study of PM as a potential target for diamondback moth (Plutella xylostella) control. The objectives of the 3-year project are as the following. In the first year, we propose to 1) dissect the ultrastructure of PM by electron microscopy, and 2) proteomic identification of PM proteins in P. xylostella; 3)dissecting the structure of peritrophin by bioinformatics technique; In the second year, 1) cloning and expression of chitiase and chitin synthesis from P. xylostella, 2) regulatory mechanisms of chitin biosynthesis, and 3) the role of chitin in PM formation in the midgut of P. xylostella; In the third year, 1) characterization of insecticidal activity of chitinase and chitin synthesis, and 2) development of a PM-targeted bioinsecticide. According to this study, we can directly unravel the structure and composition of PM in P. xylostella. The information obtained from this study is essential for developing methods for targeting the PM by various mechanisms.小菜蛾幾丁質圍食膜peritrophic membranechitinPlutella xylostella