Rit contributes to stress-mediated MSK1/2 and CREB activation.
A, active Rit provokes MSK1/2 and CREB activation. PC6 cells expressing either Flag-EV or Flag-RitQ79L (2 μg) were serum-starved for 5 h prior to preparation of total cell lysates. The phosphorylation levels of individual protein were detected by immunoblotting with appropriate phospho-specific antibody as indicated. The results are representative of three individual experiments. B–D, Rit is required for stress-mediated MSK1/2 and CREB activation. PC6 cells were transfected with either shCTR or shRit208 (1.5 μg) in the presence of Myc-CREB-WT and Myc-MSK1-WT (0.25 μg, respectively) and subjected to G418 selection (400 μg/ml) for 60 h. Enriched PC6 cells were serum starved for 5 h prior to H2O2 (100 μm) (B), etoposide (20 μm) (C) or TNFα (50 ng/ml) (D) exposure for 5, 10, 30, 60, or 120 min, and total cell lysates subjected to phospho-specific immunoblotting. The results are representative of 3 to 5 independent experiments.