Mice homozygous for this En2flox-taulacZ (also called En2-floxLacZ, En2tau-lacZ, or En2-tau-lacZ) mutation are viable but may not breed well (reported as "semi-fertile"). These mice harbor a loxP-flanked tau β-galactosidase "knock-in" allele that also abolishes engrailed 2 (En2) gene function. While both the tau-lacZ and En2 transcripts are made, only tau-lacZ is translated to protein. Expression of lacZ mimics that of the endogenous En2 gene. When bred to mice that express Cre recombinase, the resulting offspring will have the lacZ reporter deleted in the cre-expressing tissue(s) with subsequent restoration of En2 translation. These En2flox-taulacZ mutant mice may be useful for conditional reporter protein expression in En2-expressing tissues (including the early mesencephalon and rhombomere 1, and developing cerebellum and jaw muscles), as well as for conditional restoration of En2 function.
Of note, these mice may also be useful in conjunction with other engrailed mutants (such as Stock No. 007912, Stock No. 007916, Stock No. 007917, Stock No. 007918, and Stock No. 007924).
