Harnessing a single molecule for dual bioorthogonal regulation of RNA function and m6A methylation.

This study presents a multifunctional RNA regulation strategy that enables RNA molecules to undergo both bioorthogonal ligation and cleavage reactions within the same system. Using guide RNA (gRNA) as an example, we demonstrate on-demand inactivation via click chemistry and subsequent reactivation by light exposure. Applied to CRISPR-mediated, site-specific RNA methylation, this technology enables continuous, multistep programmable control, overcoming the one-way limitation of traditional methods. Results show that gRNA can stably tolerate both azide and photodegradable groups, facilitating efficient targeting of M3M14-dCas9 and dCas13b-M3M14 methylation systems to introduce m6A at specific RNA sites. Small molecules can turn off methylation through in situ click chemistry, while 365-nm light exposure rapidly restores gRNA function, allowing precise control over RNA methylation. This strategy highlights the efficiency and flexibility of progressive bioorthogonal RNA modulation and paves the way for multisite, dynamic regulation in complex biological systems.