G: The E14tg2a ESCs were transduced with lentiviral shRNAs targeting genes Ap2a1, Mettl22, Lrsam1, or Hal and differentiated towards HSPCs. The differentiated cells on day 20 were analyzed by flow cytometry. Flow cytometric analysis showed notable reduction of LSK population on day 20 with Group X genes Ap2a1, Mettl22, Lrsam1, or Hal knockdown.H: Quantification of flow cytometric analyses showed knockdown of Ap2a1, Mettl22, Lrsam1, and Hal significantly impaired generation of LSK population on day 20 in vitro compared to control. Error bars represent standard deviation (SD), n=3. Student's t-test, *p<0.05. 