Fig 1: Depletion of Eif2s2 in oocytes induces DNA damage and oocyte apoptosis.A Immunofluorescence staining of γH2AX, p-CHK2, p53, BAX and BCL-xL in WT and Eif2s2-ZcKO oocytes. B Immunofluorescence staining of RAD51 in WT and Eif2s2-ZcKO oocytes. C Quantification of fluorescence intensity of γH2AX, p-CHK2, p53, BAX, BCL-xL and RAD51, n = 30 oocytes in each group. D, E Western blot analysis of γH2AX, RAD51, BAX and BCL-xL expression in WT and ZcKO oocytes. F Representative images of Annexin V staining in WT and Eif2s2-ZcKO oocytes. G Quantification of fluorescence intensity of Annexin V (n = 30 oocytes). Representative images (H) and the percentage (I) of oocytes with GVBD and PB1 in Eif2s2-ZcKO mice. The oocytes were cultured for 14 h without (NAC-) or with NAC (NAC + ) treatment. n = 4, and 52-95 oocytes were analyzed in each repetition. NAC N-acetylcysteine. J Representative images of ROS detected by DCFH staining in Eif2s2-ZcKO oocytes without or with NAC treatment. K Quantification of ROS fluorescence intensity in the oocytes (n = 30). L Representative images of DDX4, FOXL2 and hematoxylin staining of ovarian sections from Eif2s2-ZcKO mice with or without anti-Müllerian hormone (AMH) treatment. M Histogram showing the ratio of transitional follicles to primordial follicles (n = 4). In each experiment, n ≥ three biological replicates. Bars indicate the mean ± SD. A two-sided Student’s t test was used to determine P values. (**P < 0.01 and ***P < 0.001). Scale bar: 25 μm (A, B, F, H, J) and 100 μm (L).