Zfp423^tm1.2Ngc

A single loxP sites was inserted just 5' of exon 4. Then an Frt flanked neomycin selection cassette followed by a second loxP site was inserted 3' of exon 4. Mice containing this targeted mutation were then crossed with transgenic mice expressing cre recombinase under the control of beta Actin. Both the neomycin selection cassette and exon 4 are deleted in the resulting mice. Northern blot analysis demonstrated the absence of full length mRNA. A weak band of a size appropriate for an exon 4 deleted mRNA is observed. (J:111316)