RNA interference (RNAi) is a mechanism of gene regulation in eukaryotes. RNAi is initiated by , which leads to the of specific genes.

RNA interference (RNAi) is a mechanism of gene regulation in eukaryotes. RNAi is initiated by double-stranded RNA (dsRNA), which leads to the silencing of specific genes.

Here are the steps:

1. Initiation: The process begins when a dsRNA molecule is introduced into the cell. This can occur naturally, as in the case of a viral infection, or artificially, as in laboratory experiments.

2. Dicing: The dsRNA is recognized and cleaved by an enzyme called Dicer. This results in small fragments of about 21-23 nucleotides in length, known as small interfering RNAs (siRNAs).

3. RISC Loading: The siRNAs are then incorporated into a protein complex known as the RNA-induced silencing complex (RISC). Within the RISC, the siRNA is unwound, and one strand (the guide strand) is retained while the other (the passenger strand) is degraded.

4. Target Recognition: The guide strand of the siRNA within the RISC then binds to its complementary sequence in the mRNA of the target gene. This binding is highly specific, allowing the RISC to recognize and bind to the correct mRNA molecule.

5. Silencing: Once bound to the target mRNA, the RISC cleaves the mRNA, thereby preventing it from being translated into protein. This effectively silences the gene.

6. Amplification: In some organisms, the process can be amplified through the action of an RNA-dependent RNA polymerase, which uses the cleaved mRNA as a template to produce more dsRNA, leading to the production of more siRNAs and thus more gene silencing.

This is a simplified overview of the RNAi process. The actual mechanism can be more complex and can vary between different organisms.