Figure 3.

Polycystin-induced branching does not require activation of the ERK1/2 pathway. (a) CD16.7-positive IMCD cells (control) and CD16.7.PKD1-positive IMCD cells (PKD1) were treated with either the specific MEK inhibitor U0126 or solvent, and subjected to branching morphogenesis assays. U0126 blocks the HGF-stimulated response, but has only a modest effect on polycystin-induced branching. (b) Polycystin-1 does not influence basal or HGF-mediated ERK1/2 phosphorylation. After stimulation with solvent or HGF, cells were harvested, and equal amounts of protein were separated by 12% SDS-PAGE and immunoblotted with antibody against phosphorylated ERK1/2.