The mutation was generated by the random insertion of the gene trap vector U3NeoSV1 into exon 12 of the gene. RT-PCR and Northern blot analysis demonstrated that a truncated transcript is produced from this allele, and western blot analysis confirmed that low levels of a truncated protein were expressed from this allele. However, the expressed product is not expected to retain activity due to missing nucleic acid binding domains. (J:60213)