Figure 2.

Effect of GEFΔDH on G protein-mediated SRF activation. NIH 3T3 cells were cotransfected with 0.1 μg of SRE.L-luciferase reporter plasmid, 0.1 μg of GFP expression construct, and 0.05 μg of various wild-type forms of G protein subunits in the presence (solid bar) or absence (open bar) of 0.2 μg of GEFΔDH (A) or LbcΔDH (B). LacZ (z) expression plasmid was used to make the total amount of DNA equal (0.5 μg per well) in all transfections. Assays were carried out as described in Fig. 1. The expression of Gα13 was detected by an antibody specific to Gα13 (C), and GEF115 and its mutants were detected with an anti-myc antibody that recognizes the myc-tag in these proteins (D).