Hprt1^{tm1(CAG-EGFP)Laumm}

The following sequences were inserted in place of the endogenous promoter, exons 1-2 and 5' end of intron 2, which are lacking in the Hprtb-m3 allele-containing ES cels: the CAG promoter, a loxP site flanked STOP cassette, sequence coding for a chimeric peptide joining the 17-amino acid F-actin-binding Lifeact peptide to monomeric EGFP, poly(A) signal sequence and human HPRT promoter and exon 1 and mouse Hprt intron 1, exon 2 and part of intron 2. Mice carrying this allele will only express the Lifact-EGFP fusion protein when crossed with mice expressing a cre recombinase allele. (J:275378)