Fig. 4

Unique cellular characteristic of hPSCs affecting genome editing outcome (A) hPSCs are highly susceptible to DNA damage (Primed to apoptosis). Upon DNA damage, p53 preferably translocates to mitochondria disrupting the mitochondrial membrane permeability (MMP) by direct interaction to BCL2-xL or BAK. Disrupted MMP induce cytochrome C (Cyt C) release into cytosol, which provokes mitochondrial dependent apoptosis. The transcription of cell cycle inhibitors by p53 to induce cell cycle arrest is markedly attenuated in hPSCs. (B) Deamination of C, producing U activates BER. U is readily recognized and removed to produce AP site by DNA glycosylase such as UNG. The high BER activity in hPSCs affects CBE outcomes. (C) Prime editor (PE) synthesizes DNA strand containing edit (3’ flap). The 3’ flap bound to non-editing strand is recognized by MutS and MutL homologs, major components of mismatch repair (MMR). Highly active MMR determines PE efficiency. Created with BioRender.com