Fig. 5

Fig. 5

Inactivation of MMEJ and cNHEJ DNA repair pathways through CRISPR/Cas9-mediated gene knockout. (A-C) Schematics depicting the different gene knockout strategies used to inactivate the MMEJ and cNHEJ pathways. (A) Inactivation of the nuclear isoform of DNA ligase 3 (nLig3) was performed by inducing a small in-frame deletion of the nuclear isoform’s start codon. (B) The polq gene coding for DNA polymerase theta (Polθ) was knocked out by inducing a large deletion causing a frameshift early in the open reading frame. (C) The lig4 gene coding for DNA ligase 4 was knocked out by inducing a large deletion of the coding sequence by targeting non-coding DNA on either side.