Inactivation of Icmt inhibits transformation by oncogenic K-Ras and B-Raf
J. Clin. Invest. Martin O. Bergo, et al. 113:539 doi:10.1172/JCI18829 [Go to this article.]

Figure 7
Low steady-state levels of RhoA in Icmt-deficient fibroblasts. (a) GTP-bound Rho proteins were immunoprecipitated from 1 × 10⁶ K-Ras-Icmt^flx/flx fibroblasts and derivative K-Ras-Icmt^Δ/Δ fibroblasts with equal amounts of Rhotekin-GST (Rho Activation Kit; Upstate Biotechnology Inc.). The GTP-bound Rho proteins were resolved by SDS-PAGE and detected with a RhoA-specific antibody (26C4 monoclonal; Santa Cruz Biotechnology Inc.). In the same experiment, bands for two control proteins were of identical intensity in the K-Ras-Icmt^flx/flx and K-Ras-Icmt^Δ/Δ fibroblasts (not shown). Similar results were obtained when using a pan-Rho antibody. (b) Cell extracts from K-Ras-Icmt^flx/flx fibroblasts and the derivative K-Ras-Icmt^Δ/Δ fibroblasts were analyzed by immunoblotting with a RhoA-specific antibody. The blot was stripped and incubated with an anti-Erk1/2 antibody as a loading control. (c) Northern blot (NB) of total cellular RNA from K-Ras-Icmt^flx/flx fibroblasts and the derivative K-Ras-Icmt^Δ/Δ fibroblasts was hybridized with a mouse RhoA cDNA probe. Reprobing of the membrane with a Gapdh cDNA probe revealed similar levels of Gapdh expression in each sample (see Figure 5d).