Protein Recoding Through RNA Editing: Detection, Function, Evolution

RNA editing is an endogenous post-transcriptional process that alters the RNA sequence, changing its information content from that encoded in the DNA. Throughout the animal kingdom, the most common type of RNA editing is A-to-I editing, catalyzed by double-stranded RNA-specific adenosine deaminase (ADAR) enzymes. ADARs mostly target non-coding RNA sequences. However, some protein-coding regions are modified, resulting in non-synonymous substitutions and novel protein products. These editing sites, also known as “recoding” sites, contribute to the complexity and diversification of the proteome. Computational transcriptomic studies have identified thousands of recoding sites in multiple species, many of which are conserved within lineages. However, the functional impact of recoding, in most cases, is yet to be revealed. In this chapter we discuss the utility of recoding for diversity and adaptation throughout evolution.