Development of new defense systems in mosquito for West, Nile virus infection in Japan

本研究的目的是明确JNK的生物功能，建立控制蚊子生长的方法，并在此基础上开发新的杀虫剂。2003年和2004年的研究阐明了以下内容。1.通过将JNK抑制剂（SP600125）暴露于白纹伊蚊一龄幼虫，成功地阻碍了生长。在蚊子培养细胞中，确认JNK具有以下功能： 2.通过向蚊子细胞中添加脂多糖(LPS)观察到JNK的激活，并从细胞中发现了编码抗菌肽的新基因。3.检查了siRNA的转染方法以评价JNK的功能。尽管对三龄幼虫微注射针对JNK的siRNA会导致蚊子的生长减少，但对许多幼虫进行微注射方法是不可能的。然后，我们尝试改进使用转染试剂的siRNA方法。但未能获得优于显微注射法的结果。4.在含有真菌源性昆虫几丁质酶抑制剂的培养基中培育一龄幼虫，两种培养基均阻碍其生长。编码抑制剂的基因目前正在鉴定中。在这项研究中，我们阐明了 JNK 在蚊子中发挥着重要作用。此外，几丁质酶的有效抑制剂可用于抑制蚊子的生长。

The purpose of this research is establishment the method of controlling mosquito's growth by clarifying biological functions of JNK, and development of a new insecticide based on this fundamental research.The following were clarified from the research in 2003 and 2004.1.It was succeeded in the obstruction of growth by exposing a JNK inhibitor (SP600125) to first instar larvae of Aedes albopictus In mosquito cultured cell, JNK was confirmed to have a function of anti-apoptosis.2.JNK was observed the activation by adding Lipopolysaccharide(LPS) to mosquito cells, and a novel gene, which should code anti-bacterial peptide, was discovered from the cells.3.The transfection method of siRNA was examined for evaluating the function of JNK. Although inicroinjection siRNA against JNK to third instar larvae lead to decrease growth of mosquito, it was impossible to handle microinjection method to a lot of larvas. Then, we tried to improve the method of siRNA using reagents for transfection. However, we could not obtain superior to the microinjection method.4.First instar larvae was bred in the culture medium containing potent insect chitinase inhibitors of fungal origin, and the growth was obstructed by two kinds of culture medium. The gene that codes the inhibitors is now under identification.In this research, we clarified that JNK plays important roles in mosquito. Moreover, potent inhibitors of chitinase are useful for inhibition growth of mosquito.