A 3 kb genomic fragment of the mouse Hes5 gene, including 1.6 kb of the 5' flanking region (amplified from BAC clone RP23-333L21), was placed upstream of the Enhanced Green Fluorescent Protein (EGFP) gene. The transgene construct was injected into the male pronucleus of fertilized DBF1 oocytes. Three stably expressing lines were established: 21, 27 and 48. (J:119796)