FIGURE 6.

Effect of a premature stop codon on the translation efficiency of Renilla luciferase. Renilla specific activity (RLUs/sec/ng protein) per unit mRNA was determined for the indicated strains using dual luciferase reporter plasmids containing either the UGAC or CGAC tetranucleotides. The ratio of these values (UGAC/CGAC) serves as a measure of the relative translational efficiency. Assuming translation elongation rates are constant, this ratio should provide a measure of the relative levels of translation initiation in the UGAC and CGAC reporter plasmids.