FIGURE 1.

Schematic representation of TPI/Renilla luciferase reporter constructs. (A) Human triose phosphate isomerase (TPI) exons 6 and 7 were cloned in frame at both ends of the Renilla luciferase ORF (no intron). TPI intron 6 was inserted at either end to generate the 5′ and 3′ intron constructs. (B) Increasing the amount of transfected 5′ intron plasmid elicits a linear increase in mRNA levels. RPA was performed 24 h post-transfection with probe K (Fig. 2C ▶). Two-hundred-fifty nanograms (lanes 1,3,5,7,9,11) or 1 μg (lanes 2,4,6,8,10,12) total RNA was used for RPA. (C) Renilla luciferase activity increases linearly with increasing mRNA levels. mRNA levels are represented relative to 100 ng DNA transfected. (LU) Luminescence units.