Fig. 3

The application of the frame-shift CFP (FsCFP) reporter in two other cell lines also can effectively detect genome editing events with good quantitative quality and low background signals. See Additional file 1: Figure S4 and S5 for the background CFP signal of these cells. a The host cell CHO was stably induced with a FsCFP reporter containing target sequence derived from hVEGF. To initiate genome editing, vectors containing Cas9 and either the corresponding gRNA, a mutant gRNA, or a non-specific (ns) gRNA were used, with GFP as a traceable marker, all similar as in Fig. 2b. On the bottom right corner is the quantification of CFP-positive events detected in mCherryFP and GFP double-positive populations. The mean value were calculated from independent repeats (n = 3). The error of means were shown. b similar to A, except that MEF were used as host cells, and that n = 5 for the cells with nsgRNA, n = 3 for other cells