Figure 5

IRES activity versus cryptic promoter activity of the coding region of Cx55.5. A) Schematic presentation of the different Di-cis constructs and the respective promoterless Di-cis constructs (see Additional File 4 for further explanation). B) IRES activity and cryptic activity of the above constructs in N2A, HeLa and NIH3T3 cells. The IRES activity is represented as the ratio of Firefly to Renilla luciferase (FLuc/RLuc) with the activity of the control vector, pRF-Di cis, set at "1". Each construct was tested three times and each experiment was done in triplicate. Data are expressed as mean ± SEM