Liu Chang-Mei, Liu De-Pei, Dong Wen-Ji, Liang Chih-Chuan
National Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, 5 Dong Dan San Tiao, Beijing 100005, PR China.
Biochem Biophys Res Commun. 2004 Jan 16;313(3):716-20. doi: 10.1016/j.bbrc.2003.11.174.
RNA interference (RNAi) is the mechanism of sequence-specific, post-transcriptional gene silencing initiated by short interfering RNAs (siRNAs) homologous to the gene being suppressed. siRNAs, which mediate sequence-specific mRNA degradation, are duplexes of about 21-23 nucleotides with 3'-overhangs synthesized in vitro or expressed by DNA-based vector. However, these systems rely on transfection for delivery and cannot generate long-term gene silencing in vivo. This obstacle may be circumvented by recently developed retrovirus- and lentivirus-delivered RNAi. Here, we describe a retroviral system for delivery of siRNA into cells, which can substantially down-regulate the expression of human p53 gene in human HepG2 cells. What's more, the G1 and S phases of cell cycle change dramatically in p53-down-regulated cells. These results indicate that retrovirus vector-delivered RNAi may be used in functional genomics and in gene therapy.
RNA干扰（RNAi）是由与被抑制基因同源的小干扰RNA（siRNA）引发的序列特异性、转录后基因沉默机制。介导序列特异性mRNA降解的siRNA是约21 - 23个核苷酸的双链体，带有3'端突出，可在体外合成或由基于DNA的载体表达。然而，这些系统依赖转染进行递送，无法在体内产生长期基因沉默。最近开发的逆转录病毒和慢病毒递送的RNAi可能会克服这一障碍。在此，我们描述了一种用于将siRNA递送至细胞的逆转录病毒系统，该系统可在人HepG2细胞中显著下调人p53基因的表达。此外，p53下调的细胞中细胞周期的G1期和S期发生了显著变化。这些结果表明，逆转录病毒载体递送的RNAi可用于功能基因组学和基因治疗。
