Figure 4

Effects of Egr - 1, Hey - 1 and ZBTB7A / LRF / pokemon on ACVR 1 promoter activity. Expression vectors carrying the cDNA of Egr-1, Hey-1 or ZBTB7A/LRF/pokemon transcription factors were transiently transfected in the HeLa (A) and ATDC5 (B) cell lines together with the three reporter ACVR1 promoter deletion constructs (Pr-2.9, Pr-0.7 and Pr-0.3) and the pRL-TK-Renilla plasmid as control for transfection efficiency. Detected activities are expressed relative to those of the same promoter construct co-transfected with empty expression vector considered as 100% (RLU, Relative Light Unit). The data represent the mean ± SD (error bars) of independent experiments (n=2 in HeLa cells, n=3 in ATDC5 cells) carried out in triplicate with p < 0.05^*, p < 0.01^**, or p < 0.001***. ev, empty vector, corresponding to the empty expression plasmid of the selected transcription factors. For the Hey-1 protein, two different cDNAs corresponding to two isoforms (indicated as v1 and v2) differing by four residues in the HLH domain were used.