Cell-cycle–related gene expression. (A) Northern blot analysis of Rb using RNA from whole embryos at E12.5. (B) Northern blot analysis of Rb using RNA from fetal livers at E12.5. (C) Western blot analysis of cdk2 using whole-body lysate at E12.5. (D) Western blot analysis of cdk4 using whole-body lysate at E12.5. (E) Western blot analysis of cyclinD1 using whole-body lysate at E12.5. (F) Western blot analysis of cyclinD3 using whole-body lysate at E12.5. +/+, Mll^+/+; +/mu, Mll^+/mu; mu/mu, Mll^mu/mu.