Ctcf^tm2.2Gal

The targeting vector was designed to insert a loxP-flanked PMC1-neomycin cassette upstream of exon 3 and a loxP-flanked PGK-puromycin cassette followed by splice acceptor sequence and a lacZ reporter downstream of exon 12. ES cells were isolated de novo from these Ctcf conditional mice, and infected with lentivirus expressing cre recombinase. ES cells without the neomycin cassette upstream of exon 3 but carrying loxP-flanked exons 3-12, and the loxP-flanked PGK-puromycin cassette with lacZ reporter downstream, were selected. (J:143271)