Myc^tm37Mnz

A targeting vector containing a self-excising lox-P flanked neomycin/sperm-specific Cre cassette was used to introduce a loxP site and an 18 bp I-SceI (S. cerevisiae) endonuclease recognition site (TAGGGATAACAGGGTAAT) into intron 1 of the gene. The construct was electroporated into CY2.4 albino C57BL/6J-Tyrc-2J-derived embryonic stem (ES) cells. Correctly targeted ES clones were injected into recipient blastocysts. The resulting male chimeric animals were crossed to C57BL/6J-Tyrc-2J mice to allow for coat-color screening of germline transmission and for self-excision of the neomycin/Cre cassette. This mutant locus is left with one loxP site and one I-SceI endonuclease recognition site 5' of exon 2. (J:145691)