Fig. 5.

Effects on ERK phosphorylation of RAS activation at the GC. a MCF-7 cells stimulated with EGF (50 ng/ml) or co-transfected with constructs expressing the indicated proteins (1 μg) with (+) or without (−) KDELr-HV12 (1 μg). ERK phosphorylation was assayed by immunoblotting. b As in a, but cells were co-transfected with KDELr-Cdc25. c ERK phosphorylation is inhibited by GC RAS via RALGDS. Cells were transfected with HRASV12 (+) together with the indicated KDELr-tethered RAS effector domain mutants (1 μg each). d As in c, cells were transfected with constructs encoding for the indicated effector proteins (1 μg each). Representative results are shown in every case. e RALGDS cooperates with GC RAS for inducing apoptosis. Apoptosis in MCF-7 cells transfected with the indicated constructs (1 μg each) or treated with U0126 (10 μM, 24 h). Data show average ± SEM from three independent experiments *p < 0.05 by Student's t-test. See also Supplementary Fig. 5