Post-cleavage target residence determines asymmetry in non-homologous end joining of Cas12a-induced DNA double strand breaks.

ABSTRACT:

Background

After Cas12a cleaves its DNA target, it generates a DNA double strand break (DSB) with two compatible 5'-staggered ends. The Cas12a-gRNA complex remains at the protospacer adjacent motif (PAM)-proximal end (PPE) while releasing the PAM-distal end (PDE). The effects of this asymmetric retention on DSB repair are currently unknown.

Results

Post-cleavage retention of LbCas12a at PPEs suppresses the recruitment of classical non-homologous end joining (c-NHEJ) core factors, leading to longer deletions at PPEs compared to PDEs. This asymmetry in c-NHEJ engagement results in approximately tenfold more accurate ligation between two compatible PDEs induced by paired LbCas12a than ligation involving a compatible PPE. Moreover, ligation to a given end of SpCas9-induced DSBs

SUBMITTER: Chen RD 

PROVIDER: S-EPMC11998249 | biostudies-literature | 2025 Apr

REPOSITORIES: biostudies-literature