Small RNA-Mediated Control of Development in Plants

In the last decade, it became clear that RNA–RNA interactions are extremely important in the regulation of gene expression. Indeed, although a large portion of most eukaryotic genome is actively transcribed into RNA, only a small fraction encodes proteins. In many cases, long non-protein-coding RNAs are processed into small RNAs, 20–30 nucleotides in length, which regulate gene expression through base pairing with complementary sense RNA. Such mechanisms fine tune regulate the expression of genes during development and serve as a flexible, sequence specific, source of regulation that promotes adaptability in response to biotic and abiotic stresses. In this chapter, we review studies that uncovered the mode of action of the different classes of small RNAs during the development of plants.