AE up-regulates MPL to promote Bcl-xL expression and self-renewal. (A) UCB cells were transduced with control vector (CON) or AE overnight, followed by recovering the cells in fresh growth media for 2 to 3 days, and lysis for RNA extraction. Quantitative PCR was then performed to detect MPL transcript levels. The c-abl transcript was used as normalizer. Data represents mean ± SD (n = 6; *P < .05). (B) UCB cells transduced with vector control (CON) or AE were sorted and cultured in the absence or presence of THPO for 48 hours, followed by lysis for immunoblotting of indicated proteins. (C) UCB cells transduced with vector or MPL-expressing retroviruses were sorted and cultured in the absence or presence of THPO for 48 hours, followed by lysis for immunoblotting of indicated proteins. (D) UCB cells transduced with vector or MPL-expressing retroviruses were sorted and plated in methylcellulose media. Number of colonies was scored at day 14. Cells were then collected for replating.