Source: wikibot/small-interfering-rna
= Small interfering RNA
{wiki=Small_interfering_RNA}
Small interfering RNA (siRNA) is a class of double-stranded RNA molecules, typically about 20 to 25 base pairs in length, that play a crucial role in the process of RNA interference (RNAi). siRNA is involved in the regulation of gene expression and the defense against viral infections and transposable elements in cells.