体形特征是昆虫最重要的可见遗传性状之一。合适的体形能够极大的增强昆虫对外界环境的适应性，对其生存和繁衍有着至关重要的意义。在昆虫体形构建过程中，关于表皮蛋白参与躯体外部形态轮廓建立的机制还不是很清楚。在鳞翅目模式昆虫家蚕中，定位克隆研究结果显示：体形代表性突变石蚕（stony）的候选基因BmCPst为RR1型几丁质结合表皮蛋白基因。本项目在前期研究工作的基础上，以石蚕为模式材料，将从表皮的超微结构与关键因子的组织定位、BmCPst的表达模式、表达沉默后的表型表现、突变表型回复、BmCPst蛋白与几丁质的关系及其对表皮力学性能和幼虫适应与活动能力的影响等多个方面详细研究其功能，解析石蚕突变的分子机理。这不仅有助于深入理解鳞翅目幼虫体形构建的分子调控机制，也为这类基因在鳞翅目害虫生态防治中的潜在利用提供线索和理论参考。

Body shape is one of the most important visible and heritable traits of insects. Appropriate body shape can significantly enhance the adaptive ability of insects to environment, thus is of great importance to their survival and reproduction. In the process of body shape formation in insects, the mechanism of cuticle proteins involving in establishing the external morphology outline is not well understood. In the silkworm, model insect of Lepidoptera, according to the results of positional cloning, the gene responsible for the representative body shape mutation stony, BmCPst has been proven to be a RR1-like chitin binding cuticle protein gene. Based on our previous work, this project uses the stony mutant as a model, investigates the function of BmCPst gene and the molecular mechanism of stony mutation by: analysis of ultrastructure of cuticle and localization of crucial factors; analysis of BmCPst expression pattern; exhibition of mutation phenotype by repression of BmCPst; rescue of stony phenotype; interaction of BmCPst with chitin and its influence on mechanical properties of the cuticle, adaptive abilities of silkworm larva and locomotion. This project can not only give us insights into the molecular regulation mechanism of body shape formation of Lepidoptera larva, but also can provide clues and references on the potential role BmCPst plays in Lepidoptera pest ecological control.