RNAinterferenssiin

RNAinterferenssi, often abbreviated as RNAi, is a natural biological process found in most eukaryotic organisms. It is a mechanism that regulates gene expression by silencing messenger RNA (mRNA) molecules. This silencing prevents the mRNA from being translated into proteins, effectively turning off specific genes.

The RNAi pathway is triggered by double-stranded RNA (dsRNA). When dsRNA is present in the cell, an enzyme called Dicer recognizes and cleaves it into smaller fragments, typically 21-25 nucleotides long, known as small interfering RNAs (siRNAs) or microRNAs (miRNAs). These small RNA molecules then associate with a protein complex called the RNA-induced silencing complex (RISC).

Within the RISC complex, one strand of the siRNA or miRNA is used as a guide to locate complementary mRNA molecules. Once the target mRNA is bound, the RISC complex can either cleave the mRNA directly, leading to its degradation, or inhibit its translation into protein. This precise targeting allows for highly specific gene silencing.

RNAi plays crucial roles in various cellular processes, including defense against viruses and transposons, as well as the regulation of developmental pathways and gene expression. Due to its ability to specifically silence genes, RNAi has also become a powerful tool in scientific research for studying gene function and has therapeutic potential for treating diseases caused by gene overactivity.