FIGURE 7.

The activation of Akt in thymocytes is dependent on the phosphorylation of Tyr-737. Thymocytes from c-Cbl^+/+ and F/F littermates were stimulated with anti-CD3 + anti-CD4 (A) or anti-CD3 + anti-CD28 (B) antibodies for the indicated times at 37 °C before lysis and immunoblotting with phosphospecific or protein-specific antibodies. The numbers under each stimulated track refer to densitometry readings that have been normalized for protein loading and expressed as values relative to the phosphoantibody signal for +/+ thymocytes after 5 min of stimulation.