Knockdown of PKC-α in Jurkat cells decreases TCR-induced Akt phosphorylation. Jurkat cells were transfected with PKC-α or nonsense siRNA as described in Methods. Forty-eight hours later, the transfected cells were starved in RPMI 1640 overnight, then harvested for stimulation. The cell lysates were resolved by SDS-PAGE, blotted with phospho-antibodies against Akt (Ser473), p70S6K and S6, then reprobed with a loading control. Data shown represent one of four independent experiments. *P<0.05, **P<0.01.