RNA Editing by Adenosine Deaminases that Act on RNA (ADARs)

Abstract

Adenosine deaminases that act on RNA (ADARs) give rise to the most abundant form of RNA editing found in Metazoa. ADAR proteins convert adenosines to inosines within structured and double-stranded RNAs. Since inosines are interpreted as guanosines by several cellular machineries, the consequences of editing can be widespread. In messenger RNA, alterations of codons, changes in splice patterns, and influences on RNA stability have been observed as a result of RNA editing. Moreover, A to I editing has been shown to interconnect with the RNA interference machinery. In this chapter, an overview on ADAR enzymes, their molecular architecture, occurrence, and substrate specificity is given. Consequences of editing, studies in model organisms, and implications for other double-stranded RNA-dependent processes are discussed.