Figure 2.

Testing the inducible nature of the lac-operator-repressor system. 5x10⁴ SiHa cells were transfected in triplicate with either 0.2 μg pOPRSVI-Luc alone or co-transfected with various amounts of pCMV-LacI as indicated. After 39 h selected cells were treated with 25 mM IPTG and incubated for a further 9 h prior to luciferase analysis. Statistical analysis was performed using the Kruskal-Wallis test and Mann Whitney tests due to heterogeneity of variances (*, p< 0.05; ns = not significant).