A rox-flanked STOP, herpesvirus internal ribosomal entry site followed by a Cre recombinase was integrated into the endogenous Lgals3 locus after the stop codon in exon 6. A rox-flanked-STOP inserted before the IRES can be removed by dre recombinase allowing the expression cre recombinase from endogenous Lgals3 promoter. (J:318676)