A fusion protein of the DNA binding domain of yeast GAL4 to three copies of a nuclear localization signal (nls) and the human Myc epitope tag is expressed under the control of the CMV promoter. A high level of the protein is ubiquitously expressed. In combination with transgenic or knock-in strains carrying the target sequence for Gal4, UAS, the Gal4-myc fusion protein is targeted to the predetermined location with the UAS target site. (J:91713)