Effect of C-terminal truncation on RON-RON160-mediated cell proliferation: NIH3T3 cells expressing RON, RON160 or others (1 × 105cells/well) were cultured in triplicate in a 96-well plate in DMEM with 5% FBS. Cells were stimulated with 2 nM of mAb Zt/g4 for 5 days. Cell numbers were determined as previously described . Parental NIH3T3 cells were used as the control. Results shown here are from one of three experiments with similar results.