Study of Protein Constituents of Lepidopteran Peritrophic Membranes

动物在生态系统中面临着无数的环境挑战。消化道是与环境接触并与各种物理、化学和生物因素相互作用的主要部位。特别是，肠道的细胞外基质衬里，在高等动物中通常是粘液层，在无脊椎动物(尤其是昆虫)中是围食膜(PM)，直接与环境相连，是第一道防线。因此，理解质膜的形成和功能对于了解昆虫与植物或动物宿主、微生物以及来自环境的各种非生物因素的相互作用是至关重要的。PMS是由甲壳素和蛋白质组成的一种独特的细胞外基质，其结构和功能依赖于蛋白质。本研究的目的是了解PM蛋白在PM结构和形成中的功能。通过沉默单个PM蛋白基因在鳞翅目昆虫中的表达来研究PM蛋白的功能，以揭示这些蛋白在PM形成中的作用，并通过分析单个PM蛋白基因在PM伤害和取食不同寄主植物时的表达来研究PM蛋白合成的动态调节及其在与寄主植物相互作用中的功能。此外，还将研究主要的PM蛋白--昆虫肠道粘蛋白与其他PM蛋白的相互作用，以确定蛋白质-蛋白质相互作用在PM结构和形成中的作用。这项拟议的研究有望对PM的分子特性和功能有更广泛和深入的了解，这将促进对PM在昆虫生理、生物化学和分子生物学领域的了解，并有助于了解昆虫与环境的相互作用，包括它们的寄主动植物、微生物和其他环境因素。从这个项目中获得的知识可能会指导制定控制农业和医学上重要的害虫的新战略，以利于公益事业。这项研究是一项研究与教育相结合的项目。它将为博士后以及研究生和本科生提供培训机会，这是主要调查人员计划的一个组成部分。

Animals face numerous environmental challenges in the ecosystem. The digestive tract is a primary site interfacing with the environment and interacting with various physical, chemical and biological factors. Particularly, the extracellular matix lining of the gut, which is often a mucus layer in higher animals and is the peritrophic membrane (PM) in invertebrates (especially in insects), directly interfaces with the environment and serves as the first line of defense. Therefore, understanding of the formation and function of the PM is fundamental for understanding the interactions of insects with their plant or animal hosts, microorganisms and various abiotic factors from the environment. PMs are a unique extracellular matrix composed of chitin and proteins, and their structure and function are critically dependent on the proteins. The aim of this research is to understand the function of PM proteins in PM structure and formation. The function of PM proteins will be investigated by silencing the expression of individual PM protein genes in a Lepidoptera insect, Trichoplusia ni, to reveal the roles of the proteins in PM formation and by profiling the expression of individual PM protein genes in response to PM damage and to feeding on different host plants to examine the dynamic regulation of PM protein synthesis and their function in interaction with host plants. In addition, interactions of the major PM protein, the insect intestinal mucin, with other PM proteins will be examined and characterized to identify the role of protein-protein interaction in the PM structure and formation. This proposed research is expected to result in a broad and in-depth understanding of the molecular properties and function of the PM, which will advance the understanding of the PM in the areas of insect physiology, biochemistry and molecular biology and facilitate the understanding of the interactions of insects with the environment, including their host plants/animals, microorganisms and other environmental factors. The knowledge derived from this project may direct development of new strategies for the control of agriculturally and medically important insect pests for public welfare. This proposed research is an integrative project of research and education. It will provide opportunities for postdoctoral and both graduate and undergraduate student training, which is an integral component of the principal investigators program.