Diagrams of experimental and control plasmid vectors. Abbreviations: cTnT, rat cardiac troponin T promoter; fluc, firefly luciferase gene; PA, SV40 poly(A) tail; hrluc, synthetic Renilla luciferase gene; CMVenh, cytomegalovirus enhancer; TSTA, two-step transcriptional amplification; Gal4–VP2, fusion gene combining yeast Gal4 and two tandem repeats of herpes simplex virus VP16; 8xGal4bs, 8 tandem repeats of Gal4-binding site; E4, adenovirus E4 minimal promoter; hrluc/M185V, gene expressing the mutant RLuc (RLuc/M185V) with enhanced light output; CMV, cytomegalovirus promoter.