RNAi, also known as RNA interference is a type of method that uses small fragments of RNA to interfere the molecular expression of mRNA. When inside an eukaryotic organism (RNAi), it transcribes a pre-shRNA (a strand of RNA that forms a hairpin when folded) and is then cleaved via a dicer (removing the loop) to form smaller fragments of double-stranded 20 bps RNA.
The RNAi function is then performed through the use of RISC(RNA-induced silencing complex). [Through the use of RISC (RNA-induced silencing complex) to recognize the complimentary mRNA, the function of RNAi is then performed].
Through the artificial modifications, the 20 bps of RNA is then sent into the cell to achieve the function where we may control the expression of gene translation.
When RNAi recognizes its complimentary strand, three things may happen:
1. mRNA simply gets degraded,
2. Blocks mRNA transcription,
3. It controls the promoter and related enzymes after this
stand of RNA is transcribed.
The main advantage of RNAi is that it is very easy and handy to use. You do not need to go through transgenic procedures to achieve gene regulation. The cons of RNAi on the other hand is that it “knocks down” a gene instead of “knockout” hence, meaning that it cannot completely suppress certain genes.
The mechanism of RNA interference is probably originated form an organism that is infected by a virus. The RNA of the virus enters into the cell and is then recognized and cleaved by the dicer into small fragments. These small fragments possess the function of RNAi hence, inhibiting the original physiological mechanism of the cell.
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