Fig. 2

Zebrafish Tgfbr3 promoter activity increases during myogenic differentiation. C2C12 myoblasts were transfected with the full-length zebrafish Tgfbr3 promoter reporter construct p3.2tgfbr3:luc (full) or its 5′ truncated deletion mutants (indicated as Δ, with the kbp remaining in the plasmid), or with the murine BG promoter, or the pGL3 basic or pGL3 promoter negative or positive control vectors. Each one of these plasmids were co-transfected with a constant amount of a beta-galactosidase constitutive reporter. The cells were subjected to differentiation conditions and luciferase and galactosidase activities were determined. The beta-galactosidase-normalized luciferase activities obtained before (day 0) or after 4 days of differentiation are shown in the graph. The ratio of the normalized luciferase activity at day 4 over day 0 is indicated on the right margin of the graph as fold increase. Positions of the discussed myogenic responsive elements (arrowheads) and putative binding sites for Sox6 (S) and Prdm1a (P) are indicated.