Fig. 3

Fig. 3 Zebrafish Fog proteins bind and repress GATA4. Zebrafish Fog proteins can physically interact with GATA4. In panel A, in vitro translated, ³⁵S-labeled Fog1, Fog2a, or Fog2b proteins (column 1) were incubated with bacterially produced GST (column 2) or GST-GATA4 (column 3) fusion proteins and purified using glutathione sepharose beads. The resultant complexes were resolved by 7% SDS-PAGE and detected by autoradiography. A physical interaction of GATA4 and Fog proteins is indicated by the presence of ³⁵S-labeled protein in column 3. Zebrafish Fog proteins can repress GATA4 mediated transcriptional activation. In panel B, NIH 3T3 fibroblasts were transfected with a reporter plasmid containing 638 bp of the ANF promoter driving expression of human growth hormone (hGH). In addition, expression plasmids for murine GATA4 (columns 2–5) and zebrafish fog1 (column 3), fog2a (column 4), or fog2b (column 5) were included. Forty-eight hours post-transfection, cells were harvested and assayed for hGH. Results are reported as the mean ± SEM (n = 12).