AKT and GATA-1 synergize in up-regulating red cell gene expression in G1E cells. GATA-1 and constitutively active AKT^* were retrovirally transduced in G1E cells in the absence of Epo; 24 hours later, cells were FACS sorted and cultured for another 24 hours before preparing RNA for real-time PCR analysis (top) and protein for Western blot analysis (bottom) using the indicated antibodies. One of 2 independent experiments is shown.