Fig. 3.

Dual-target editing factor pentatricopeptide repeat protein PPR56 expressed in the E. coli system with efficient editing of nad4eU272SL and partial editing of nad3eU230SL site. Designation of PPRs, numbering of positions, shading, and the scoring of editing efficiencies is as in Fig. 2. Single point mutations have been introduced into each of the two targets to match the respective other sequence. For the nad4eU272SL target, a combination of all three exchanges and a variant to fully match the PPR-RNA code concept have also been tested (middle). Additionally, the perfect match of an A in position −12 opposite of P-9TN was changed into G in both targets