title: Inhibition of CRISPR/Cas9-Mediated Genome Engineering by a Type I Interferon-Induced Reduction in Guide RNA Expression.
abstract: Clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9-mediated genome engineering technology is a powerful tool for generation of cells and animals with engineered mutations in their genomes. In order to introduce the CRISPR/Cas9 system into target cells, nonviral and viral vectors are often used; however, such vectors trigger innate immune responses associated with production of type I interferons (IFNs). We have recently demonstrated that type I IFNs inhibit short-hairpin RNA-mediated gene silencing, which led us to hypothesize that type I IFNs may also inhibit CRISPR/Cas9-mediated genome mutagenesis. Here we investigated this hypothesis. A single-strand annealing assay using a reporter plasmid demonstrated that CRISPR/Cas9-mediated cleavage efficiencies of the target double-stranded DNA were significantly reduced by IFNα. A mismatch recognition nuclease-dependent genotyping assay also demonstrated that IFNα reduced insertion or deletion (indel) mutation levels by approximately half. Treatment with IFNα did not alter Cas9 protein expression levels, whereas the copy numbers of guide RNA (gRNA) were significantly reduced by IFNα stimulation. These results indicate that type I IFNs significantly reduce gRNA expression levels following introduction of the CRISPR/Cas9 system in the cells, leading to a reduction in the efficiencies of CRISPR/Cas9-mediated genome mutagenesis. Our findings provide important clues for the achievement of efficient genome engineering using the CRISPR/Cas9 system.
authors.affiliation: Laboratory of Biochemistry and Molecular Biology, Graduate School of Pharmaceutical Sciences, Osaka University.
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Machitani
authors.forename: Fuminori
authors.initials: F
authors.lastname: Sakurai
authors.forename: Keisaku
authors.initials: K
authors.lastname: Wakabayashi
authors.forename: Kosuke
authors.initials: K
authors.lastname: Nakatani
authors.forename: Kazuo
authors.initials: K
authors.lastname: Takayama
authors.forename: Masashi
authors.initials: M
authors.lastname: Tachibana
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Mizuguchi
mesh_terms: D000072283:A549 Cells; D064112:Clustered Regularly Interspaced Short Palindromic Repeats; D004247:DNA; D004526:Efficiency; D004720:Endonucleases / Q000378:metabolism; D005818:Genetic Engineering / Q000379:methods*; D005822:Genetic Vectors / Q000276:immunology*; D016678:Genome; D005838:Genotype; D006801:Humans; D007370:Interferon Type I / Q000096:biosynthesis* / Q000378:metabolism; D016296:Mutagenesis; D009154:Mutation; D010957:Plasmids; D000094704:RNA, Guide, CRISPR-Cas Systems / Q000378:metabolism*
chemical_list: D007370:Interferon Type I; D000094704:RNA, Guide, CRISPR-Cas Systems; D004247:DNA; D004720:Endonucleases