FIG. 8.

Multiple effector pathways regulated by RhoA contribute to the transformation phenotype of p53^−/− MEF cells. (A) Involvement of ROCK in the RhoAL63-elicited transformation of p53^−/− MEFs. Colony-forming activities of p53^−/− MEFs transduced with the RhoAL63 mutant or ROCK1 in the presence or absence of Y27632 (20 μM) were determined 14 days postplating. (B) Effector domain mutants of RhoA allow selective uncoupling of RhoA with ROCK, PKN, or other effectors. Single-point mutants made in the switch I domain of RhoA impair or retain specific effector binding as depicted. (C) The effect of effector domain mutations on active RhoA-induced transformation of p53^−/− cells. Expression of the respective RhoAL63 mutants in the p53^−/− cells was detected by anti-HA Western blot. The data shown are representative of two independent experiments. WT, wild type.