Pcolce^{tm1d(EUCOMM)Wtsi}

The L1L2_Bact_P cassette was inserted at position 137604738 of Chromosome 5 upstream of the critical exons 4-7b (Build GRCm39). The cassette is composed of an FRT site followed by lacZ sequence and a loxP site. This first loxP site is followed by a neomycin resistance gene under the control of the human beta-actin promoter, SV40 polyA, a second FRT site and a second loxP site. A third loxP site is inserted downstream of the targeted exons 4-7b at position 137607834. The critical exons 4-7b are thus flanked by loxP sites. Flp-mediated recombination generated a "conditional ready" (floxed) allele. Subsequent cre expression deleted exons 4 to 7b resulting in a knock-out mouse. (J:322653)