Fig. 1.

Schematic of Cas12a MITI, Cas12a HITI, and Cas9 HITI gene knock-in strategies. a Schematic of the Cas12a MITI system. The Cas12a MITI-based method needs to introduce modified compatible CrRNA target sequences in the donor. b Schematic of the Cas12a HITI system. The Cas12a HITI-based method requires a CrRNA target site in the donor in reverse orientation to the genomic target sequence resembling the Cas9 HITI approach. c Schematic of the Cas9 HITI system. The Cas9 HITI strategy requires an identical sgRNA target site in the donor but in reverse orientation to the genome target sequences. Green “TTTN” is the PAM sequence for the Cas12a. The gray scissors represents the Cas12a nuclease, and the black scissors represents the Cas9 nuclease