(b) dRagA and dRagC are not required for dAkt phosphorylation. Drosophila S2 cells untreated (lanes 1-3) or treated with the indicated RNAi were starved of amino acids for 1 h and stimulated with amino acids for 30 min. Phosphorylation and protein levels of dAkt were determined by immunoblotting with appropriate antibodies as indicated. NC, negative control RNAi. 