Impaired Akt pathways in ATF3-null MCs. (A) WT or ATF3-null MCs were cultured in IL-3/SCF for 5 weeks, starved of growth factor for 6 hours, washed, then cultured in IL-3 (30 ng/mL) or SCF (50 ng/mL) or both for the indicated times (in minutes). Whole-cell lysates were analyzed by Western blot with antibodies against phosphorylated Akt, total AKT. (B) After sensitization with anti-DNP IgE, MCs were stimulated with KLH-DNP for the indicated times. Whole-cell lysates were analyzed by Western blot with antibodies against phosphorylated Akt, total AKT. (C) WT or ATF3-null MCs were starved for 6 hours, washed, and then cultured in IL-3 (30 ng/mL) or SCF (50 ng/mL) or both for the indicated times. Whole-cell lysates were analyzed by Western blot with antibodies against phospho-Bad and total Bad.