The Diversity, Biogenesis, and Activities of Endogenous Silencing Small RNAs in Arabidopsis

In eukaryotic RNA silencing, RNase-III classes of enzymes in the Dicer family process double-stranded RNA of cellular or exogenous origin into small-RNA (sRNA) molecules. sRNAs are then loaded into effector proteins known as ARGONAUTEs (AGOs), which, as part of RNA-induced silencing complexes, target complementary RNA or DNA for silencing. Plants have evolved a large variety of pathways over the Dicer–AGO consortium, which most likely underpins part of their phenotypic plasticity. Dicer-like proteins produce all known classes of plant silencing sRNAs, which are invariably stabilized via 2′-O-methylation mediated by HUA ENHANCER 1 (HEN1), potentially amplified by the action of several RNA-dependent RNA…