Fig. 2From: A multiplex guide RNA expression system and its efficacy for plant genome engineeringtRNA following U6 promoter does not increase the total editing efficiency of a single gRNA in wild tobacco protoplasts. a Structure of two types of gRNA expression systems: AtU6-gRNA and AtU6-tRNA-gRNA. b Comparison of indel mutation frequency between two different gRNA expression systems: AtU6-gRNA and AtU6-tRNA-gRNA. We designed 28 gRNAs to induce indel mutations in 12Â N. attenuata genes. The coding sequences of the target genes are presented as black pentagons. Each gRNA is shown as a black arrow. Targeted deep sequencing was performed to examine indel frequency and mutation patterns at the target site. The indel frequency (%) was calculated by dividing the number of sequencing reads containing indel mutations by the number of total sequencing reads. Error bars represent standard deviation of three replicates (pools of protoplasts). AtU6, Arabidopsis U6-26; gRNA, guide RNA; tRNA, pre-tRNAGly geneBack to article page