Zea mays Genome sequencing

The promoters for driving both Cas9 and sgRNAs are quite important for efficient genome editing by CRISPR/Cas9 in plants. Here we use maize DMC1 gene promoter combined with maize U3 promoter for HspCas9 and sgRNA driven, respectively. Two DPC Cas9-positive T0 plants with zb7 gene edited and one wild type T0 plant without Cas9 were chosen for whole genome resequencing to detect off-target mutation. No off-target mutation was detected in the predicted loci with sequence similarity to the target loci. Our results show that the DMC1 promoter-controlled CRISPR/Cas9 system is highly efficient in maize and provided further evidence that the optimization of the promoters used for CRISPR/Cas9 system is much important for enhancing the targeted genome editing in plants.