C-型凝集素在棉铃虫抗细菌感染的血细胞免疫激活中的作用机理

项目名称： C-型凝集素在棉铃虫抗细菌感染的血细胞免疫激活中的作用机理

项目编号： No.31201578

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 植物保护学、园艺学与植物营养学

项目作者： 刘杨

作者单位： 中国农业科学院植物保护研究所

项目金额： 25万元

中文摘要： 先天免疫在昆虫抵抗病原菌入侵的过程中有非常重要的作用。C-型凝集素是昆虫先天免疫系统中重要的模式识别受体。现有研究已证明C-型凝集素参与了多种血细胞先天免疫反应的激活，然而其具体的作用机制尚待进一步的研究。申请者已证明一种棉铃虫C-型凝集素能够通过促进血细胞的吞噬作用增强棉铃虫抗细菌感染的能力。在此基础上本项目将对一种新的棉铃虫C-型凝集素（Ha-CTL2）进行深入研究。通过实时定量PCR和原位杂交，研究Ha-CTL2的表达模式；通过测定体外活力，研究Ha-CTL2可以识别的细菌类型；通过RNAi，验证Ha-CTL2的体内功能；通过Pull-down等实验，从基因和蛋白水平筛选和鉴定HaCTL2功能相关免疫因子。本研究将阐明C-型凝集素在棉铃虫血细胞免疫激活中的功能及作用机理。不仅为进一步了解昆虫先天免疫的分子机理奠定基础，而且在此基础上可以从中发现可资利用的新靶标，为害虫防治提供新思路。

中文关键词： 先天免疫；C-型凝集素；血细胞；棉铃虫；细菌

英文摘要： The innate immune system is very important for resisting pathogen invasions in insects. C-type lectin is an important pattern recognition receptor in the insect innate immune system. Previous studies has proved that C-type lectin is involved in the activation of a variety of haemocyte-mediated immune responses. However, the detailed mechanism is largely unknown. Our work indicated that a C-type lectin of Helicoverpa armigera (Ha-CTL) could function as a pattern recognition receptor in vivo to promote the haemocyte phagocytosis of pathogens and protect the insect from bacterial infection. In this proposal, we would like to perform funtional study on a new C-type lectin (Ha-CTL2). The expression patterns of Ha-CTL2 will be analysis by real-time PCR and in situ hybridization. The bacteria binding activity of Ha-CTL2 will be determined by in vitro study. The in vivo function of Ha-CTL2 will be verified by RNAi experiments. The immune cofactors of HaCTL2 will further be screened and identified from gene and protein levels by RNAi, real-time PCR, Pull-down and other methods. Ultimately, this study could clarify the function and mechanism of C-type lectin in haemocyte-mediated immune responses activation of Helicoverpa armigera. It not only lays the foundation for better understanding of the molecular mechanism of the

英文关键词： innate immunity；C-type lectin；haemocyte；Helicoverpa armigera；bacteria