What process does RNA interference (RNAi) involve?

RNA interference (RNAi) is a biological process that involves the inhibition of gene expression or translation. It is a vital mechanism by which cells regulate the expression of genes. The primary function of RNAi is to target and degrade messenger RNA (mRNA) that corresponds to specific genes, thereby preventing the production of proteins encoded by those genes. This is achieved through small RNA molecules like small interfering RNA (siRNA) and microRNA (miRNA) that bind to the mRNA and either cause its degradation or inhibit its translation into proteins.

In contrast, amplifying gene expression would imply enhancing the production of mRNA and subsequently the protein, which is not the function of RNAi. Transcribing RNA into DNA, a process known as reverse transcription, is carried out by the enzyme reverse transcriptase and pertains to the behavior of certain retroviruses, rather than being a function of RNA interference. Replicating RNA molecules is also distinct, as this refers to the process of making copies of RNA and is not associated with the regulatory effects seen in RNAi. Thus, RNA interference is characterized by its crucial role in the regulation and silencing of gene expression.