FIG. 4.

Loss of full-length Neuralized transcript in Neuralized knockout mice. Total RNA isolated from adult brain or skeletal muscle was analyzed using a cDNA probe containing sequence 5′ (left panel) or 3′ (right panel) to the integration site of the targeting cassette (see Materials and Methods). Northern hybridization with the 5′ probe yields transcripts of the expected size in wild-type tissues and aberrantly migrating transcripts in the tissues derived from Neuralized null animals. The right panel shows normal transcripts in the wild-type controls but loss of transcription of sequence 3′ to the integration site of the targeting vector in Neuralized null animals.