Fig. 6. SRE-mediated gene transcription by constitutively active α₁₃ mutants.

(A) pSRE-Luc (0.05μg) and pCMV-βgal (0.1 μg) were cotransfected into HEK293 cells with either 0.85 μg of pcDNA3 (vector) alone, or with 0.84 μg pcDNA3 and 10 ng of the indicated α₁₃ constructs. 25 ng C3-transferase was also co-expressed with α₁₃QL as indicated. (B) HEK293 cells were cotransfected with 2.5 to 25 ng of α₁₃ constructs as indicated, and pSRE-Luc, pCMV-βgal, and pcDNA3. Cells were lysed 24 h after transfection, and assayed for luciferase activity and β-galactosidase activity. Luciferase activity was normalized by the β-galactosidase activity present in each lysate. Results are presented as percentage activity with respect to control cells (vector) and are the means +/− S.E. of results obtained from (A) 3 independent experiments performed in duplicate (N=6) or (B) 2 independent experiments performed in duplicates (N=4). The statistical difference between the indicated mutant and constitutively active α₁₃QL is indicated by asterisks (*p<0.05).