RNA interference (RNAi) is a highly conserved phenomenon in evolution, which is induced by efficient and specific degradation of double-stranded RNA (dsRNA) and homologous mRNA. Gene silencing mainly includes two types: pre-transcriptional horizontal gene silencing (TGS) and post-transcriptional horizontal gene silencing (PTGS): TGS means that genes cannot be transcribed normally due to DNA modification or chromosome heterochromism; PTGS initiated the degradation mechanism of target mRNA sequence specificity in cytoplasm. Sometimes genetic modification can lead to TGS and PTGS.
RNAi technology is widely used to explore gene function and the treatment of infectious diseases and malignant tumors because it can specifically eliminate or shut down the expression of specific genes (dsRNA with a length over 30 will cause interferon toxicity).