Small Molecule-Catalyzed Deamination: Applications in Transcriptome-Wide Profiling of N6-Methyladenosine in RNA (human)

We present a novel N-nitrosation strategy for deamination capable of tolerating DNA/RNA biological macromolecules under mild conditions. A cooperative catalysis combining a carbonyl organocatalyst with a Lewis acid catalyst facilitates the formation of a C-nitro intermediate from a primary amine, which, upon rearrangement into N-nitrosamine, leads to selective deamination of unsubstituted canonical DNA/RNA bases under mild conditions. We employed this new approach to deamination of adenine into hypoxanthine, read as guanine by reverse transcriptases or DNA polymerases, while N6-methyladenosine (m6A) sites resist deamination and remain identified as adenine. We therefore report a chemically mild, low-input detection method for adenosine methylation sequencing at base resolution, named Chemical cooperative catalysis-Assisted for m6A sequencing (CAM-seq). Overall design: CAM-seq were applied to human cell lines samples, using polyA enriched RNA.