FIGURE 4.

TPA causes an increase in Cx46 mRNA levels. A, reverse transcription PCR and B, quantitative real-time PCR was completed as described under “Experimental Procedures.” section. Both A and B show that, although the Cx43 message level remains constant throughout the different time periods indicated, Cx46 message was up-regulated up to 3-fold in response to TPA treatment. β-Actin was used as a housekeeping control gene. Quantitative real-time PCR data in B is plotted as the -fold change in message over the control untreated HLECs message level. The asterisks indicate significantly different amounts of message levels in comparison to the control (p < 0.05). Data are representative of three independent experiments.