Ltf^tm1.2Smoc

An FRT-flanked neomycin resistance cassette with a 3' loxP site was inserted upstream of exon 3. An additional loxP site was inserted downstream of exon 3. Flp-mediated recombination removed the selection cassette and left exon 3 floxed. Cre-mediated recombination removed exon 3. Western blot analysis confirmed the absence of protein expression in bone marrow. (J:219007)