Potentiality of small interfering RNAs (siRNA) as recent therapeutic targets for gene-silencing.

In recent years, RNA interference (RNAi) is one of the most important discoveries. RNAi is an evolutionarily conserved mechanism for silencing gene expression by targeted degradation of mRNA. Short double-stranded RNAs, known as small interfering RNAs (siRNA), are incorporated into an RNA-induced silencing complex that directs degradation of RNA containing a homologous sequence. siRNA has been shown to work in mammalian cells, and can inhibit viral infection and control tumor cell growth in vitro. Recently, it has been shown that intravenous injection of siRNA or of plasmids expressing sequences processed to siRNA can protect mice from autoimmune and viral hepatitis. In this review, we have discussed about the discovery of RNAi and siRNA, mechanism of siRNA mediated gene silencing, mediated gene silencing in mammalian cells, vectored delivery of siRNA, pharmaceutical potentiality of siRNA from mice to human. We have also discussed about promise and hurdles of siRNA or RNAi that could provide an exciting new therapeutic modality for treating infection, cancer, neurodegenerative disease, antiviral diseases (like viral hepatitis and HIV-1), huntington's disease, hematological disease, pain research and therapy, sarcoma research and therapy and many other illness in details. It will be a tool for stem cell biology research and now, it is a therapeutic target for gene-silencing.