A bioluminescent transgenic mouse model: Real-time in vivo imaging of antioxidant EC-SOD gene expression and regulation by interferon gamma

• EC-SOD promoter-reporter bioluminescent mice were created.
• Reporter luminescence was highest in testes, aorta and perirenal fat.
• Inducible expression of the reporter regulated similarly to the endogenous gene.

Extracellular superoxide dismutase (EC-SOD) is the main antioxidant enzyme in the extracellular matrix. We developed transgenic mice to analyze the EC-SOD promoter activity in vivo in real time and to identify the important cis-elements flanking the 5′ region of the murine EC-SOD gene. Using this model, we demonstrated that luciferase reporter activity correlates closely with endogenous EC-SOD expression, although several interesting differences were also observed. Specifically, luciferase activity was detected at the highest levels in testes, aorta and perirenal fat. Reporter expression was regulated by interferon gamma, a finding that is in agreement with published endogenous EC-SOD gene expression studies. Thus, the 5′-flanking region of mouse EC-SOD gene is responsible, at least in part, for cell specific and inducible expression.