Cpt1a^em1Fink

Theoriginal targeting construct is composed of an FRT site followed by a lacZ sequence and a loxP site inserted upstream of exon 4. This first loxP site was followed by neomycin under the control of the human beta-actin promoter, SV40 polyA, a second FRT site and a second loxP site. A third loxP site was inserted downstream of exon 4. The construct, clone HEPD0727_3_A09, was introduced into C57BL/6N-Atm1Brd-derived JM8A3.N1 embryonic stem (ES) cells. Flp-mediated recombination removed the FRT-flanked lacZ and neo cassette. It was then determined that the third loxP site was absent and the ES cell line was retargeted using CRISPR/Cas9 genome editing to insert a loxP site downstream of exon 4. (J:270066)