PDGF-BB-induced Akt phosphorylation involves the PLC/PKC pathway. NIH3T3 cells (A and E), dnPLCγ PAE cells (B), PLCγ-null (C) and Rictor null (D and F) MEFs were serum-starved for 24 h and then stimulated with PDGF-BB (20 ng/ml) with or without pretreatment with the inhibitor U73122 (5 μM) and SB203580 (10 μM) for 1 h, or with or without PMA (1 μM) for 24 h, as indicated. Akt phosphorylation level at S473 and T308, as well as mTOR, S6, PLCγ, PKCα and pMarcks phsphorylation and the total protein expression were assayed by immunoblotting (Ib) of total cell lysate. β-actin immunoblotting served as a loading control. The relative protein phosphorylations were quantified for a representative experiment.