Nkx3-2^tm1Tno

The entire coding region, spanning exons 1 and 2, was replaced with a cassette containing an NLS-lacZ gene and a floxed neo gene. The cassette was inserted at the translational start codon, which enabled expression of beta-galactosidase from the endogenous promoter. Northern blot analysis of total RNA obtained from homozygous mutant embryos showed a lack of transcript. (J:77612)