Fig. 5

CDC42 regulates PTEN expression levels in oocytes of primordial follicles. a The expression of PTEN gradually decreased with the development of postnatal ovaries in mice. b CDC42 and PTEN were expressed in a mutually exclusive manner in oocytes of follicles. Ovaries at 3 dpp were sectioned and stained for PTEN (green) or CDC42 (red) in adjacent sections. Nuclei were dyed with a Hoechst counter-stain (blue). High expression of CDC42 was observed in activated oocytes (arrows) in the medulla region, whereas PTEN was mainly expressed in dormant oocytes in the cortical region of ovaries. c Suppression of CDC42 increased the expression of PTEN in ovaries. The ovaries were collected at 2 dpp and then cultured with or without ML141 for 5 days. Almost all oocytes exhibited a high expression of PTEN (green) in the ML141 group. d Oocyte counting results showed that the proportion of PTEN-positive oocytes increased from 36.08 ± 7.26% in the control group to 86.90 ± 3.32% in the ML141 group (Additional file 10: individual data values). e Western blot showed that PTEN expression was increased in 7 dpp ovaries after 5 days of ML141 treatment compared with controls. f Over-expressing CDC42 decreased the expression of PTEN in ovaries. One dpp ovaries were transfected with empty lentivirus or a lentiviral construct expressing Cdc42 (Cdc42-OE) for 2 days or 6 days in vitro. Few oocytes with PTEN expression were observed in Cdc42-OE ovaries. g The proportion of oocytes with PTEN expression was significantly decreased in Cdc42-OE ovaries (6.61 ± 2.30%) compared with the control (40.28 ± 4.60%) (Additional file 10: individual data values). h PTEN expression was downregulated in Cdc42-OE-treated ovaries compared to controls. The experiments were repeated at least three times, and representative images are shown. Scale bars, 50 μm