Collaborative Research: An Integrated Functional Genomics Investigation of Chitin Metabolism and its Role in Insect Growth and development

该项目是对一种具有重要经济意义的害虫物种(红粉甲虫)的甲壳素代谢的合作、集成的生化/遗传学研究，具有完整的基因组测序，并拥有一套完善的用于功能基因组后续研究的遗传工具包。甲壳素是一种结构性碳水化合物聚合物，是昆虫角质层(相当于皮肤)的基本成分，也存在于中肠的内层。由于甲壳素不存在于高等动植物中，甲壳素代谢是一种昆虫选择性靶标，可用于特定的害虫控制，而不会对那些被认为有益的昆虫造成伤害。最近完成了由NSF-NHGRI资助的甲虫基因组测序，从而能够鉴定出这种昆虫的大部分基因，这些基因对甲壳素的合成、修饰和周转非常重要。这些基因的功能将通过RNA干扰(RNAi)技术进行分析，这将导致选定基因产物的特定下调。针对甲壳素代谢的个别基因的RNAi实验的形态、生理和发育效果将被确定，并与商业上用于昆虫控制的选定的“甲壳素抑制剂”的效果进行比较。这些靶基因编码的蛋白质也将被提纯，几丁质抑制剂对其活性的影响将得到证实。从这些研究中获得的知识将有助于识别用于害虫控制目的的新的靶标生理过程。该项目还将帮助培训EPSCoR机构昆虫功能基因组学领域的研究生、研究生和本科生。在学年和夏季期间，将鼓励来自代表性不足的少数民族和女性的本科生参加我们的研究。特别是，将利用正在进行的SUROP、McNair和NSF-REU方案，努力从少数族裔机构招收学生。

This project is a collaborative, integrated biochemical/genetic study of chitin metabolism in a pest species (red flour beetle) that is economically important, has a completely sequenced genome, and has a well-developed genetic toolkit for functional genomic follow-through. Chitin, a structural carbohydrate polymer, is an essential component of the insect cuticle (the equivalent of the skin) and also found in the lining of the midgut. Since chitin is not present in higher animals or plants, chitin metabolism represents an insect-selective target that can be exploited for specific control of pest insects without harm to those that are deemed beneficial. The recent completion of the sequencing of the beetle genome funded by NSF-NHGRI has enabled the identification of most if not all of the genes from this insect, which are important for chitin synthesis, modification and turnover. The functions of each of these genes will be analyzed by the technique of RNA interference (RNAi), which results in specific down-regulation of the products of selected genes. The morphological, physiological and developmental effects of RNAi experiments targeted towards individual genes of chitin metabolism will be determined and compared with the effects of selected "chitin inhibitors," which are commercially utilized for insect control. The proteins encoded by these target genes will also be purified and the effects of chitin inhibitors on their activities will be confirmed. The knowledge obtained from these studies will help identify novel target physiological processes for insect pest control purposes. This project will also help train post-graduate, graduate and undergraduate students in the field of insect functional genomics at an EPSCOR institution. Undergraduate students from underrepresented minorities and women will be encouraged to participate in our research both during the academic year and summer months. In particular, attempts will be made to recruit students from minority institutions utilizing the ongoing SUROP, McNair and NSF-REU programs.