Foxn1^tm1Nrm

The insertion of sequence encoding GFP into exon 3 resulted in the generation of a hypomorphic allele lacking exon 3. Though the floxed neo cassette used for selection was excised, inverted repeats at the insertion site of the remaining loxP site may be the reason for the aberrant splicing. Mutant transcript was detected by Northern blot, RT-PCR, and RNase protection. Sequence analysis of the RT-PCR products showed that exon 2 spliced directly to exon 4, producing a transcript lacking exon 3 similar to a splice variant found at low levels in wild-type mice. The transcript putatively encodes protein lacking 154 residues from the N-terminal domain, but containing the nuclear localization signal and DNA-binding and C-terminal acidic activation domains. (J:86255)