Extended Data Fig. 6: On- and off-target prime editing at Trp53 in pancreatic organoids.
From: A prime editor mouse to model a broad spectrum of somatic mutations in vivo
a Editing efficiency and indel byproduct frequency of epegRNAs encoding Trp53M240FS-14nt (n = 4 independent transductions) or Trp53M240S* (n = 4 independent transductions) in Trp53flox/+ pancreatic organoids. Data and error bars indicate the mean and standard deviation across independent transductions. b Design of the epegRNAs for Trp53M240FS-14nt or Trp53M240S*. The black line below the sequence schematics indicates the Cas9 nicking site. These epegRNAs were designed to both evade MMR and modify the seed and PAM sequences. c CRISPResso allele frequency plots of prime edited reads for Trp53M240FS-14nt before and after nutlin selection in pancreatic organoids. d Quantification of off-target prime editing for an epegRNA encoding Trp53M240FS-14nt. Off-targets represent four computationally predicted loci for pancreatic organoids cultured for more than one month in the presence of the Trp53M240FS-14nt epegRNA and nutlin-3a or a control pegRNA. Data and error bars indicate the mean and standard deviation of three independent transductions. e Quantification of off-target prime editing for an epegRNA encoding Trp53R245Q. Off-targets represent four computationally predicted loci for pancreatic organoids cultured for more than one month in the presence of the Trp53R245Q epegRNA and nutlin-3a or a control pegRNA. Data and error bars indicate the mean and standard deviation of three independent transductions. f Quantification of off-target prime editing for an epegRNA encoding Trp53R245W. Off-targets represent four computationally predicted loci for pancreatic organoids cultured for more than one month in the presence of the Trp53R245W epegRNA and nutlin-3a or a control pegRNA. Data and error bars indicate the mean and standard deviation of three independent transductions. Statistical significance was calculated using an unpaired, one-tailed Welch’s t-test (P = 0.0045 for the leftmost off-target site).
