A method to identify RNA A-to-I editing targets using I-specific cleavage and exon array analysis

RNA A-to-I editing is the most common single-base editing in the animal kingdom. Dysregulations of RNA A-to-I editing are associated with developmental defects in mouse and human diseases. Mouse knockout models deficient in ADAR activities show lethal phenotypes associated with defects in nervous system, failure of hematopoiesis and reduced tolerance to stress. While several methods of identifying RNA A-to-I editing sites are currently available, most of the critical editing targets responsible for the important biological functions of ADARs remain unknown. Here we report a method to systematically analyze RNA A-to-I editing targets by combining I-specific cleavage and exon array analysis. Our results show that I-specific cleavage on editing sites causes more than twofold signal reductions in edited exons of known targets such as Gria2, Htr2c, Gabra3 and Cyfip2 in mice. This method provides an experimental approach for genome-wide analysis of RNA A-to-I editing targets with exon-level resolution. We believe this method will help expedite inquiry into the roles of RNA A-to-I editing in various biological processes and diseases.