Chemical modifications regulate the fate and function of cellular RNAs. Newly developed sequencing methods have allowed a deeper understanding of the biological role of RNA modifications; however, the vast majority of post-transcriptional modifications lack a well-defined sequencing method. Researchers from York University have now developed a photo-oxidative sequencing (PhOxi-seq) approach for guanosine N2-methylation, a common methylation mark seen in N2-methylguanosine (m2G) and N2,N2-dimethylguanosine (m22G). Using visible light-mediated organic photoredox catalysis, m2G and m22G are chemoselectively oxidized in the presence of canonical RNA nucleosides, which results in a strong mutation signature observed during sequencing. PhOxi-seq was demonstrated on various tRNAs and rRNA to reveal N2-methylation with excellent response and markedly improved read-through at m22G sites.
PhOxi-Seq – single-nucleotide resolution n2G RNA sequencing
Chung K, Mahdavi-Amiri Y, Korfmann C, Hili R. (2022) PhOxi-Seq: Single-Nucleotide Resolution Sequencing of N2-Methylation at Guanosine in RNA by Photoredox Catalysis. J Am Chem Soc [Epub ahead of print]. [abstract]