The resistance mechanism of plants against virus infection

植物抵抗病毒侵染的机制

基本信息

批准号：
12052222
负责人：
OKUNO Tetsuro
金额：
$ 39.87万
依托单位：
KYOTO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research on Priority Areas
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2005
项目状态：
已结题

项目摘要

Okuno's group found that to suppress Red clover necrotic mosaic virus (RCNMV) needs multiple viral components, including viral RNAs and putative RNA replicase proteins. A close relationship between the RNA elements required for negative-strand RNA synthesis and RNAi suppression suggests a strong link between the viral RNA replication machinery and the RNAi machinery. DCL1 mutants of Arabidopsis thaliana did not support RCNMV infection, suggesting DCL1 is a host component required for RCNMV infection. RCNMV preferentially interferes with the accumulation of long small-interfering RNAs (24-26 nt) in RNAi induced by a hairpin dsRNA. We propose a model in which, to replicate, RCNMV deprives the RNAi machinery of a factor that is probably a dicer-like protein, and suppresses Dicer-mediated dsRNA cleavage. They also found that the stem-loop structure that functions as a trans-activator for the RNA-mediated CP expression is critically required for RNA2 replication of RCNMV itself.Watanabe's group found that DCL1 catalyzes at least the first and second cleavage steps in miRNA biogenesis and that double-stranded RNA-binding domains of DCL1 are involved in positioning of the cleavage sites. Our result is direct evidence that DCL1 is involved in processing of pri-and pre-miRNA. (dsRNA )-binding domains of DCL1 are involved in positioning of the cleavage sites. They also identified several proteins associated with Tobacco mosaic virus movement protein in plasmodesmata.

Okuno的小组发现，要抑制红色三叶草坏死的摩西病毒（RCNMV）需要多种病毒成分，包括病毒RNA和假定的RNA复制酶蛋白。负链RNA合成所需的RNA元素与RNAi抑制之间的密切关系表明，病毒RNA复制机制与RNAi机械之间存在牢固的联系。拟南芥的DCL1突变体不支持RCNMV感染，这表明DCL1是RCNMV感染所需的宿主成分。 RCNMV优先干扰由发夹dsRNA诱导的RNAi中长的小型RNA（24-26 nt）的积累。我们提出了一个模型，在该模型中，复制RCNMV剥夺了可能是丁香样蛋白的因子的RNAi机械，并抑制了迪切尔介导的DSRNA裂解。他们还发现，作为RNA介导的CP表达的跨激活剂的干循环结构至少需要RCNMV本身的RNA2复制。Watanabe的组发现DCL1至少在miRNA生物发生中至少催化了第一和第二的裂解步骤DCL1的双链RNA结合域参与了切割位点的定位。我们的结果是直接证据表明DCL1参与PRI-MIRNA的处理。（DSRNA）DCL1的结合域参与切割位点的定位。他们还鉴定了几种与疟原虫中烟草病毒运动蛋白相关的蛋白质。