HyperTRIBE identifies many more in vivo targets of a RNA-binding protein than TRIBE

Most current methods to identify cell-specific RNA binding protein (RBP) targets require analyzing an extract, a strategy that is problematic with small amounts of material. To address this issue, we developed TRIBE, a genetic method that expresses an RBP of interest fused to the catalytic domain of the RNA editing enzyme ADAR. TRIBE therefore performs Adenosine-to-Inosine editing on candidate RNA targets of the RBP. However, editing is limited by the efficiency of the ADARcd and may fail to identify some RNA targets. Here we characterize HyperTRIBE, which carries a hyperactive mutation (E488Q) of ADAR. HyperTRIBE identifies dramatically more editing sites than TRIBE, many of which were also identified by TRIBE but at a low editing frequency. The HyperTRIBE data also overlap more successfully with CLIP data, further indicating that HyperTRIBE has a reduced false negative rate and more faithfully recapitulates the known binding specificity of its RBP than TRIBE. . CC-BY 4.0 International license peer-reviewed) is the author/funder. It is made available under a The copyright holder for this preprint (which was not . http://dx.doi.org/10.1101/156828 doi: bioRxiv preprint first posted online Jun. 27, 2017;