Fig. 1
Evaluation of various CRISPR-Cas systems in NHEJ-mediated genome editing using perfectly matched spacers or spacers with overlapping seeds. a, b Summary of matched target site activities (see Additional file 1: Figure S4) for SpCas9, either a SaCas9 or b NmCas9, AsCpf1, and LbCpf1 based on deep sequencing. Each horizontal bar indicates the mean of the editing activities for the indicated enzyme and range of spacer lengths. c, d Extent of genome modifications at a target locus in the c CACNA1D or d PPP1R12C gene whereby the Cas9 and Cpf1 nucleases had overlapping seed regions. Three different spacer lengths (17, 20, and 23 nt) were tested. The editing efficiencies were determined by deep sequencing. The cells were harvested 24 h after transfection. Data represent mean ± standard error of the mean (s.e.m.; n ≥ 6). e The editing activity of NmCas9 and the two Cpf1 nucleases at nine new target sites (C1–C9) of the form TTTN-N24-25-NNNNGATT (see Additional file 1: Table S5). The cells were harvested 24 h after transfection and then the editing frequencies were quantified by deep sequencing. Data represent mean ± s.e.m. (n ≥ 4). f Strip chart summarizing the editing efficiencies of NmCas9, AsCpf1, and LbCpf1 at perfectly matched target sites of longer lengths (24–25 nt)