摘要： RNA干涉是指由特定双链RNA(dsRNA)引起的转录后基因沉默现象。研究表明，Dicer断裂dsRNA产生的小干涉RNA可以抑制哺乳动物体细胞和胚胎中的基因的表达。 RdRP在扩增RNAi中起着关键性的作用,RdRP活性复制较长的触发性dsRNA或以一种非引物的方式复制短的siRNA，即以siRNA为引物的RdRP反应使靶mRNA转变为dsRNA，同时复制触发性dsRNA。 所有的产物又可作为Dicer的底物，起始RdRP级联反应。本文综述了RNAi可能的作用机制，并对RNAi在分析功能基因组、药物治疗等方面的应用前景进行了展望。
Abstract:RNA interference(RNAi) is the process of sequence-specific,post-transcriptional gene silencing initiated by double-stranded RNA(dsRNA).Recent studies showed small interfering RNAs(siRNA) generated by Dicer from longer dsRNA specifically suppressed expression of genes in somatic and embryo cells.An RdRP activity might provide amplification by replication of long trigger dsRNAs or copying of short siRNAs in a primer-independent manner.The siRNA primed RdRP reaction converts target mRNA into dsRNA,as well as possibly replicating trigger dsRNA.Both products then serve as DICER substrates,initiating the RdRP chain reaction.The article reviewed possible mechanisms of RNAi and pointed out the promising future of RNAi as a tool for studying gene function and used in gene-specific therapeutics.