FIG 6 .

Models for DSB repair at the hemizygous RFP locus by homology-mediated repair and NHEJ. (A) Schematic diagram of homology-mediated and NHEJ pathways of DSB repair in RFP in the absence of donor repair fragment. A variety of homology-directed repair pathways between duplicated RPS1 loci are possible. Both flip-out and single-strand annealing (SSA) are consistent with the observed simultaneous loss of both RFP and HIS1 when a DSB is introduced in RFP. (B) Alignment of the wild-type RFP sequence with that of RFP amplified from a white colony isolated after CRISPR mutagenesis in the absence of a donor repair fragment. The sequence targeted by the RFP gRNA is underlined in red and precedes the PAM site (AGG, denoted with blue asterisks) at n = 132. Note that the deletion begins 3 bases from the PAM, precisely at the predicted Cas9 cleavage site.