Loss of THPO/MPL signaling leads to Bcl-xL down-regulation in AE cells. (A) AE cells were washed with PBS 3 times, followed by culture with KTF36, TF36 (-K), KF36 (-T), or KT36 (-F) for 7 days. Proteins were then extracted for Western blotting. (B) AE cells transduced with indicated shRNA for 2 days were sorted and lysed for Western blotting. (C) AE cells were treated with indicated antibodies in the absence of THPO (but in the presence of KF36) for 1.5 hours, followed by adding THPO to the indicated groups for additional 24 hours. Cells were then lysed for Western blotting. (D-E) AE cells incubated with indicated cytokines for 24 hours were lysed for immunoblotting. (F) AE cells were treated with vehicle control (DMSO), a MEK inhibitor (PD98059), a PI3K inhibitor (LY294002) or a JAK2 inhibitor (CP690550) at indicated concentrations for 24 hours, followed by lysis for immunoblotting.