Cux1^tm1Rhsc

A targeting vector was designed to replace the sequence encoding the homeodomain in exons 20 and 21 with a neomycin resistance gene. Immunoblot of mutant thymic nuclear extracts confirmed absence of wild-type protein and presence of a smaller protein equivalent to the predicted size of the mutant protein containing only 4 amino acids of the homeodomain and a deletion of the C-terminal repression domain. This band was present at a reduced intensity compared to the wild-type band in controls, suggesting the remaining protein has partial function and is a hypomorph. (J:100055)