Figure 2.

CRISPR/Cas9 Editing Is Mostly Repaired through the NHEJ Pathway

(A) A scheme of the DNA repair mechanism and editing efficiency screening strategies. After Cas9 binding to target site, the DSB will either be repaired through the HDR pathway; thus introducing unique restriction site, AseI, which was used for screening, or the NHEJ pathway, generating random indels that would fail to reanneal, and thus would be recognized and digested by T7E1 enzyme. (B) Cells (CasKi, HPV16 positive or HeLa, HPV18 positive) were treated with target-specific (16E6, 16E7, 18E6, or 18E7) gRNAs, WT Cas9, and repair template (for AseI and AseI + T7E1 groups) for 72 h, before the efficiency of NHEJ or HDR pathways was determined by T7E1/AseI digestion assays.