Hepatic Epo is not suppressed in P3Pro mutants. Relative Epo mRNA expression in kidneys (A) and livers (B) from mutants (dark gray bars) compared with littermate controls (light gray bars) at P2, P10, P20, and P90. Bars represent means ± SEMs (n = 3 for each genotypes and time point). *P < .05, ***P < .001.