Enzymatic modification of 5′-capped RNA and subsequent labeling by click chemistry

Holstein J., Stummer D., Rentmeister A.

Abstract

The combination of enzymatic modification and bioorthogonal click chemistry provides a powerful approach for site-specific labeling of different classes of biomolecules in vitro and even in cellular environments. Herein, we describe a chemoenzymatic method to site specifically label 5′-capped model mRNAs independent of their sequence. A trimethylguanosine synthase was engineered to introduce alkyne, azido, or 4-vinylbenzyl moieties to the 5′-cap. These functional groups were then used for labeling using typical click reactions, such as the azide-alkyne cycloaddition or the tetrazine ligation.