Strategic Base Modifications Refine RNA Function and Reduce CRISPR-Cas9 Off-Targets

In contrast to traditional RNA regulatory approaches that modify the 2'-OH group, this study explores strategic base modifications using 5-carboxylcytosine (ca5C). We developed a technique where ca5C is transformed into dihydrouracil (DHU) via treatment with borane-pyridine complex (BPC) or 2-picoline borane complex (2-PBC), leading to base mutations that directly impact RNA functionality. This innovative strategy effectively manages CRISPR-Cas9 system activities, significantly minimizing off-target effects. Our approach not only demonstrates a significant advancement in RNA manipulation but also offers a new method for the precise control of gene editing technologies, showcasing its potential for broad application in chemical biology