Proliferation and apoptosis in AKT1^−/−AKT2^−/− LT-HSCs and MPPs. (A-B) The frequency of cells in the G₀, G₁, and S/G₂/M phases of the cell cycle based on RNA (Pyronin Y) and DNA (Hoechst) content. The data in panels A and B are gated on the CD45.2⁺ LT-HSC (CD150⁺CD48⁻LSK) population. The graphs in panel B represent the mean ± SEM (n = 3). (C-D) The frequency of annexin V⁺ DAPI⁻ cells in the CD45.2⁺ LT-HSC (CD150⁺CD48⁻LSK) or CD45.2⁺ MPP (CD150⁻CD48⁻LSK) compartment. The plots in panel C are gated on the CD45.2⁺ MPP (CD150⁻CD48⁻LSK) population and represent one experiment; the graphs in panel D represent the mean ± SEM (n = 3). Panels A through D are derived from mice reconstituted 12 weeks previously with wild-type (CD45.1⁺B6.Ly5^SJL) and AKT1^−/−AKT2^−/− or AKT1^+/+AKT2^+/− FL-HSCs (CD45.2⁺Ly5^B6+).