家蚕微孢子虫BAR蛋白在寄生增殖中的作用研究

微孢子虫是一类专性细胞内寄生的真核病原微生物，其寄生增殖机制的研究仍是21世纪微孢子虫研究的重点。BAR蛋白（Bin/Aphiphysin/Rvs，简称BAR）为细胞膜的形状感受器，在膜弯曲过程中募集膜泡运输蛋白等以完成细胞膜的塑形、营养需求、细胞分裂和迁移等重要生理活动。我们在研究家蚕微孢子虫蛋白质组的过程中发现一个含有BAR结构域的蛋白NbBAR，在已报道的微孢子虫基因组中均有存在，且与酵母中参与营养获得相关蛋白Gvp36具有较高相似性。定位实验表明NbBAR可靶向酵母的细胞膜。为阐明NbBAR在寄生增殖过程中扮演的角色，本研究拟从NbBAR的表达特征、互作蛋白鉴定以及功能分析三方面切入并借助酵母回复突变等技术深入研究NbBAR蛋白如何通过维持膜形状介导胞吞胞吐作用，进而为孢子寄生增殖提供营养。本研究的开展对于推进微孢子虫寄生生物学的研究和解析微孢子虫的防控机理研究具有重要的意义。

The BAR (Bin/amphiphysin/Rvs) domain superfamily proteins have emerged as sensors of membrane curvature，thereby playing important roles in a wide variety of cellular processes, such as organelle biogenesis, membrane trafficking, cell division, cell migration，secretion, and endocytosis. Microsporidia are unicellular eukaryote microbes leading an obligatory intracellular parasitism in invertebrates and vertebrates. We found a novel spore wall protein encoded BAR domain in microsporidia, Nosema bombycis. Sequence analysis suggested Nbbar share highest similarity with Gvp36 which involved in vesicular traffic and nutritional adaptation of Saccharomyces cerevisiae and homologous genes of Nbbar are in a widespread distribution among microsporidia. Furthermore, we show that expression of NbBAR-GFP fusion protein within yeast cells, directs GFP to the membrane of yeast. These findings suggest that NbBAR may serve as an import regulator of membrane remodeling to accomplish endocytosis in microsporidian. Our proposal focus on the NbBAR function study on three aspects as following: NbBAR subcellular localization、interaction protein identification and the roles in reproduction process, we try to elucidate the role of NbBAR in the infection process of microsporidia. As now no BAR protein of microsporidia was reported, our proposal is an original work. To carry out such a project is very helpful to discover the molecular mechanisms of parasitism process of microsporidia, which contribute to resolve the prevention and control of microsporidia.