植物病毒基因沉默抑制子研究进展

Approach of Research on Gene Silencing Suppressors of Plant Virus

RNAi普遍存在于真核生物中,是植物应对外来病毒入侵的一种防御机制。但是植物病毒能通过产生不同的抑制子蛋白来抑制寄主基因沉默的发生。病毒抑制子通过干扰基因沉默的起始、siRNA的积累或干扰系统性基因沉默等方式抑制寄主的基因沉默。有的病毒抑制子蛋白还能促进病毒的积累和胞间移动,加强侵染组织的病毒病症状表现。主要阐述了RNAi的机制、病毒抑制PTGS的作用方式、几种常见的沉默抑制子以及抑制子与病毒侵染的关系。

RNAi that exists in a wide variety of eukaryotic organisms,is one of the natural plant defence mechanisms against virus infection,but can be counteracted by viruses encode suppressor proteins.It is proposed that various suppressors inhibit gene silencing by disturbing the early stages of gene silencing,the accumulation of siRNA or sequestering systemic gene silencing.Plant viral suppressors of gene silencing promoted virus accumulation and cell-to-cell movement of virus,then intensified the disease symptoms in the infected tissue.In this paper,the mechanism of RNAi,the modes of action of the suppressors,several well-known suppressors,and the relationship between the suppressors and viral infection were reviewed.