Genetic link between RNAi/PTGS & viral RNA recombination

描述（由申请人提供）：溴梅花叶病毒（BMV）系统是理解RNA重组在正链RNA病毒中的作用的一个极好的模型。最近我们已经确定溴花叶病毒（BMV），一种模式正链RNA病毒，可以在拟南芥中复制和重组（Dzianott和Bujarski，病毒学2004）。我们的长期目标是阐明宿主基因在病毒RNA重组中的作用。具体假设是RNA干扰（RNAi/PTGS）途径参与了病毒RNA重组体的生成。我们基于在拟南芥中观察到的假设：(i) RNAi/PTGS的抑制因子抑制了一种由双链结构支持的RNA重组；（ii）敲除Argonaute基因抑制拟南芥的非同源重组；（iii）同源重组受影响程度小于非同源重组。基于这些数据，本应用的实验重点是在携带受影响RNAi/PTGS通路的拟南芥系中进行BMV RNA重组。具体目标是：

DESCRIPTION (provided by applicant): The Brome mosaic virus (BMV) system is an excellent model for understanding the role of RNA recombination in plus-strand RNA viruses. Recently we have determined that Brome mosaic virus (BMV), a model plus-strand RNA virus, could replicate and recombine in Arabidopsis thaliana (Dzianott and Bujarski, Virology 2004). Our long term goal is to elucidate the role of the host genes in viral RNA recombination. The specific hypothesis is that the RNA interference (RNAi/PTGS) pathway participates in the generation of viral RNA recombinants. We base that hypothesis on the observations in Arabidopsis that: (i) the suppressor of RNAi/PTGS inhibited a type of RNA recombination that was supported by double-stranded structures; (ii) knocking-out an Argonaute gene inhibited non-homologous recombination in Arabidopsis; and (iii) homologous recombination was affected to a lesser extent than non-homologous recombination. Based on these data, the experimental focus of this application is on BMV RNA recombination in the Arabidopsis lines carrying the affected RNAi/PTGS pathway. The specific aims are to: 1. Characterize the role of DICER related host genes in recombination by using the Arabidopsis mutant lines. 2. Characterize the role of post-DICER related host genes in recombination by using the Arabidopsis mutant lines.