These Rosa26-LSL-dCas9 knock-in mice have a floxed-STOP cassette preventing expression of nuclease-deactivated dCas9 fused with the SunTag domain, and a BFP reporter under control of a CAG promoter. After exposure to Cre recombinase to remove the STOP cassette, dCas9/SunTag is expressed. The SunTag domain is made up of a peptide containing up to 24 copies of a short peptide epitope (GCN4) and a cognate single-chain antibody (scFv) that recognizes the epitope. When dCas9/SunTag is coexpressed with the antibody-transcriptional activator (TA) fusion, VP64, and a small guide RNA, the Tag allows for docking of multiple copies of the TA, VP64, to the target. Mice homozygous for the Rosa26-LSL-dCas9/SunTag knock-in allele are viable and fertile. When used in combination with single guide RNAs and a Cre source, these mice have applications in studies of in vivo, tissue specific modulation of gene expression and epigenetics and to perform scalable combinatorial genetic screens. 
 Of note, the blue fluorescent protein reporter (BFP) expression was not characterized by the donating laboratory.

The use of this mouse strain or other product (the "Licensed Product") is subject to the terms and conditions of the Limited License from The Broad Institute.

Rosa26-LSL-dCas9 mice (Gt(ROSA)26Sortm1(CAG-dCas9-SunTag)Khk) are a Cre-inducible CRISPR/Cas9 activation (CRISPRa) tool for cell type specific gene activation in vivo.

This strain is hosted by NIH's MMRRC, which partners with JAX for the distribution of this and other strains. For additional information and to purchase, please visit the MMRRC site.