Fig. 2. Effect of oocytes in promoting expression of Pfkp and Ldha mRNA and glycolytic activity in WT OOX cumulus cells. OOX cumulus cells of WT mice were co-cultured with oocytes of WT, DM, Bmp15^-/- or Gdf9^+/- mice for 20 hours; (A) relative mRNA levels of Pfkp and Ldha, and (B) glycolytic activity in the OOX cumulus cells of WT mice were examined. (C) Expression levels of Pfkp and Ldha mRNA in freshly isolated cumulus cells (Fresh), COCs and OOX cumulus cells cultured without (OOX) or with (+Oocyte) oocytes for 20 hours were assessed by real-time PCR analysis. Mean±s.e.m. The values indicated by different letters (a, b and c) are significantly different (P<0.05). (D) OOX cumulus cells of WT mice were co-cultured with oocytes of WT or Bmp15^-/- mice, and phosphorylation status of SMAD1/5/8 and SMAD2 in the OOX cumulus cells of WT mice was examined. ß-actin (ACTB) was used as a loading control. (E) Expression levels of Bmp15, Gdf9, Fgf8, Tgfb2 and Bmp6 mRNA were compared between WT and Bmp15^-/- oocytes. N.D., not detected. Mean±s.e.m.