【摘要】 RNA干扰 (RNAi)是一种新发现的通过 ds RNA介导的特异同源靶基因沉默途径。 RNAi主要包括两个步骤 :RNase 样核酸酶切割 ds RNA而生成 2 1- 2 3nt的 si RNA和 si RNA引导 RNA诱导的沉默复合体 (RISC)降解同源性靶基因 m RNA。在某些生物体中 RNAi具有放大效应。通过将 - 2 1nt si RNA导入哺乳动物细胞的 RNAi技术不仅可避免非特异干扰素反应 ,更重要的是还可介导序列特异的基因沉默。最近将 RNAi应用于许多病毒性疾病的治疗研究均取得了显著的基因沉默效果 ,预示 RNAi有望成为一种预防、治疗病毒性疾病的新手段。更多还原

【Abstract】 RNA interference (RNAi) is the process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) directs sequence specific degradation of homologous mRNA. Mechanistically, RNAi is a two step process: in the initiation step, the dsRNA is processed into small interfering RNA (siRNA) of about 21 23nt by RNase Ⅲ like ribonuclease; in the second step, siRNA is incorporated into RNA induced silencing complex(RISC) and RISC destroys mRNA that is homologous to the siRNA. In some species, RNAi has potential amplification processes. The 21nt siRNAs not only evades the nonspecific interferon response, but also induces gene specific suppression. Currently, scientists have carried out manyresearches on the therapy for viral diseases by RNAi technology and most of them have got encouraging results, which suggests that RNAi will be a novel prevention and therapy approach to viral diseases.更多还原