A luciferase coding sequence and cDNA encoding human SOD1 were cloned into a plasmid containing a bi-cistronic tetracycline operator promoter (BiTetO). The construct was injected into micronuclei. Two lines were generated. Transgene expression was determined by luciferase activity in isolated fibroblasts transfected with a CMV-tTA plasmid. Analysis using anti-SOD1 and -luciferase antibodies was also performed on fibroblasts. (J:138761)