Masayuki Sakurai

Recent developments in sequencing and bioinformatics have advanced our understanding of adenosine‐to‐inosine (A‐to‐I) RNA editing. Surprisingly, recent analyses have revealed the capability of adenosine deaminase acting on RNA (ADAR) to edit DNA:RNA hybrid strands. However, edited inosines in DNA remain largely unexplored. A precise biochemical method could help uncover these potentially rare DNA editing sites. We explore maleimide as a scaffold for inosine labeling. With fluorophore‐conjugated maleimide, we were able to label inosine in RNA or DNA. Moreover, with biotin‐conjugated maleimide, we purified RNA and DNA containing inosine. Our novel technique of inosine chemical labeling and affinity molecular purification offers substantial advantages and provides a versatile platform for further discovery of A‐to‐I editing sites in RNA and DNA.