The Fundamentals of miRNA Biology: Structure, Biogenesis, and Regulatory Functions

Abstract

Epigenetic regulation of gene expression plays a key role in controlling many cellular processes. One essential element of such regulation are miRNAs—a class of short non-coding RNAs. The miRNAs were first discovered in 1993, but their active investigation was not started until early 2000s. Recent data show that miRNAs regulate the expression of at least half of human genes. Being involved in regulation of numerous target genes implicated in cell functioning, miRNA activity is critical for normal human development and function, while dysregulation of miRNA is a hallmark of various pathophysiological processes. Current review introduces the reader to the main stages of miRNA life cycle in human cells. The origins of cellular miRNAs, their biogenesis, functions, and regulation of their activity are discussed. The publication is aimed at readers looking for first insights into the intricacies of miRNA biology, but can also serve as a source of reference material for specialists in the area.