RNA interference technology: Implications and applications - A review

RNA interference is a phenomenon in which the introduction of double-stranded RNA (dsRNA) into a diverse range of organisms and cell types causes degradation of the complementary mRNA. ShRNA, siRNA and micro RNA are the three types of small interfering RNA involved in the gene silencing mechanism. This mechanism is triggered by double stranded RNA, which is cleaved by endoribonucleases, Drosha and Dicer to produce short RNA (si RNA) duplexes of 21–25 nt in length. The siRNA is further processed such that one of the two strands, (the passenger strand) is destroyed, while the other strand (the guide strand or antisense strand) complexes with multiple proteins to form the RNA-induced silencing complex (RISC). It is the RIse that mediates sequence specific gene silencing by recognizing the m-RNA containing sequences complimentarily with the guide strand of the siRNA. Keeping in view the importance of this highly specific DNA sequence knock down mechanism and the diverse applications of this technology, this review describes the designing of siRNAs, allele specific RNA interference, inhibition of hepatitis B Virus replication by various RNAi constructs, applications in livestock and agricultural species, si RNA therapy, si RNA delivery systems and the challenges associated with it like immune stimulation and offtargeting effect, which should be obliterated in order to enhance the efficiency of this technology.