Stag1^{tm1c(EUCOMM)Hmgu}

The L1L2_Bact_P cassette was inserted upstream of the critical exon (exon 7) of the stromal antigen 1 locus (Stag1) - with insertion at bp position Chr9:100,785,969 [Build GRCm38]. The L1L2_Bact_P cassette was composed of an FRT site, a mouse En2 intron/splice-acceptor/exon (En2 SA), an IRES sequence, the beta-galactosidase gene (lacZ) with SV40 polyadenylation signal (SV40pA), a loxP site, the human beta actin promoter-driven neomycin-resistance gene with SV40 polyadenylation signal (hbactP-neo-pA), a second FRT site and a second loxP site. A third loxP site was inserted downstream of exon 7 at bp position Chr9:100,786,980 [Build GRCm38]; therefore flanking exon7 with loxP sites. Flp-mediated recombination removed the FRT-flanked neo cassette leaving exon 7 floxed. (J:157065)