Developmental potential of Ehmt2 cKO, Ehmt1 cKO, and Ehmt1/2 cDKO oocytes. (A) Representative images showing IF for EHMT2 and EHMT1 in NSN oocytes. Scale bar: 20 µm. (B) Stacked bar chart showing percentage of NSN, intermediate, and SN oocytes from mice aged 12 wk. Number of mice/oocytes: Control (Ctrl) = 5/247, Ehmt2 cKO = 3/160, Ehmt1 cKO = 2/116, Ehmt1/2 cDKO = 3/188. Ctrl versus Ehmt2 cKO: P = 0.7667; Ctrl versus Ehmt1 cKO: P = 0.0075; Ctrl versus Ehmt1/2 cDKO: P < 0.0001; Ehmt2 cKO versus Ehmt1/2 cDKO P = 0.0058. (C) Stacked bar charts showing percentage of chromosome misalignments and spindle abnormalities in MII oocytes. Examples of normal and abnormal spindles are shown in IF images. The spindle is stained with an anti-α-tubulin antibody (green), chromatin with DAPI (blue), and anti-pan-histone (red). Number of mice/MII oocytes: Ctrl = 5/46, Ehmt2 cKO = 7/57, Ehmt1 cKO = 4/49, Ehmt1/2 cDKO = 6/51. (D) Stacked bar chart showing developmental stage (%) of embryos from cKO females mated with WT males and collected on E3.5. Number of mice/embryos: Ctrl = 5/30, Ehmt2 cKO = 5/39, Ehmt1 cKO = 6/35, Ehmt1/2 cDKO = 6/29. Blastocysts: Ctrl versus Ehmt2 cKO P = 0.9939; Ctrl versus Ehmt1 cKO P = 0.0761, Ctrl versus Ehmt1/2 cDKO P = 0.0073; one-cell stage: Ctrl versus Ehmt1/2 cDKO P = 0.0406. (E) Bar chart showing number of implantation sites scored at E6.5. Dots represent single mice. Ctrl versus Ehmt1 cKO P = 0.0093; Ctrl versus Ehmt1/2 cDKO P = 0.0020. (F) Boxplots showing average litter size of females with cKO oocytes mated with WT males. Number of mice: Ctrl = 9, Ehmt2 cKO = 5, Ehmt1 cKO = 3, Ehmt1/2 cDKO = 3; number of litters: Ctrl = 60, Ehmt2 cKO = 26, Ehmt1 cKO = 0, Ehmt1/2 cDKO = 0; Ctrl versus Ehmt2 cKO: P = 0.0087.
