PHD2 and PHD3 control Epo transcription in NG2 cells. (A) Shown are Hct, RBC, and Hb values for individual Cre⁻ control (n = 38), NG2-Phd2^−/− (n = 9), NG2-Phd1^−/−Phd2^+/−Phd3^−/− (n = 2), NG2-Phd1^−/−Phd2^−/−Phd3^+/− (n = 5), NG2-Phd2^−/−Phd3^−/− (n = 8), and NG2-Phd1^−/−Phd2^−/−Phd3^−/− mice (n = 5). Bar graphs show serum EPO levels (sEPO) for control (Cre⁻, n = 18), NG2-Phd2^−/− (n = 8), NG2-Phd1^−/−Phd2^+/−Phd3^−/− (n = 2), NG2-Phd1^−/−Phd2^−/−Phd3^+/− (n = 4), NG2-Phd2^−/−Phd3^−/− (n = 5), and NG2-Phd1^−/−Phd2^−/−Phd3^−/− mice (n = 4). Data are represented as mean ± SEM; 1-way ANOVA followed by Tukey’s post hoc analysis; ***P < .001 compared with control group and ^fffP < .001 when the NG2-Phd2^−/−Phd3^−/− group was compared with the NG2-Phd1^−/−Phd2^−/−Phd3^−/− group. (B) Relative Epo mRNA levels in brain, kidney, and bone from control (Cre⁻), NG2-Phd2^−/−Phd3^−/−, and NG2-Phd1^−/−Phd2^−/−Phd3^−/− mice (n = 3-7). (Inset) Brain and kidney EPO protein levels in Cre⁻ control and NG2-Phd2^−/−Phd3^−/− (P2P3) and NG2-Phd1^−/−Phd2^−/−Phd3^−/− (P1P2P3) mice expressed as pg/mg total tissue protein (n = 3-6). Data are represented as mean ± SEM; 1-way ANOVA followed by Tukey’s post hoc analysis; **P < .01, ***P < .001 compared with control group; ^ffP < .01 for NG2-Phd2^−/−Phd3^−/− mice compared with NG2-Phd1^−/−Phd2^−/−Phd3^−/− mice. (C) Striatal (ST), hypothalamic (HYT), cortical (CTX), and hippocampal (HP) Epo mRNA levels in Cre⁻ control (n = 9), NG2-Phd2^−/− (n = 5), NG2-Phd2^−/−Phd3^−/− (n = 4), and NG2-Phd1^−/−Phd2^−/−Phd3^−/− (n = 3). Data are represented as mean ± SEM; 1-way ANOVA followed by Tukey’s post hoc analysis; ***P < .001 compared with Cre⁻ control group.