Site-Specific m6A Erasing via Conditionally Stabilized CRISPR-Cas13b Editor

N6-methyladenosine (m(6)A) on RNAs plays an important role in regulating various biological processes and CRIPSR technology has been employed for programmable m(6)A editing. However, the bulky size of CRISPR protein and constitutively expressed CRISPR/RNA editing enzymes can interfere with the native function of target RNAs and cells. Herein, we reported a conditional m(6)A editing platform (FKBP*-dCas13b-ALK) based on a ligand stabilized dCas13 editor. The inducible expression of this m(6)A editing system was achieved by adding or removing the Shield-1 molecule. We further demonstrated that the targeted recruitment of dCas13b-m(6)A eraser fusion protein and site-specific m(6)A erasing were achieved under the control of Shield-1. Moreover, the release and degradation of dCas13b fusion protein occurred faster than the restoration of m(6)A on the target RNAs after Shield-1 removal, which provides an ideal opportunity to study the m(6)A function with minimal steric interference from bulky dCas13b fusion protein.

Automated summary

Conditional m(6)A editing platform based on a ligand stabilized dCas13 editor was developed, allowing inducible expression of the editing system by controlling the presence of a specific molecule. This platform reduces interference from the bulky CRISPR protein and constitutively expressed editing enzymes in target RNAs and cells.