Extended Data Fig. 1: The maternal effect factor PADI6 is essential for early embryonic development in mice.
(a) Strategy for the generation of Padi6 knockout mice via the Cre-loxP system. (b) Western blotting showing PADI6 protein levels in GV oocytes from female Padi6Null, Padi6+/−, WT mice, with β-actin as the loading control. Three biologically repeated experiments were performed. (c) Immunofluorescent staining showing PADI6 protein levels in GV oocytes from female Padi6Null and WT mice. Three biologically repeated experiments were performed. Scale bar, 10 μm. (d) Fertility of female Padi6Null mice. Litter sizes of female Padi6+/− (cre, flox/+) and Padi6Null (cre, flox/flox) female mice after mating with Padi6+/+ (flox/flox), Padi6+/− (cre, flox/+) and Padi6Null (cre, flox/flox) males are presented as the means ± s.d. *Number of litters. †Number of females. (e) Representative images of WT and Padi6Null oocytes during oocyte maturation. Scale bars, 1 mm. (f) Percentages of oocytes that underwent GVBD and extruded their 1st polar body during in vitro maturation. WT (n = 122) and Padi6Null (n = 75) fully grown oocytes were collected after PMSG and HCG injection. (g) Representative images of preimplantation embryos derived from WT and Padi6Null female mice. Scale bars, 1 mm. (h) Development rates of 2-cell embryos and blastocysts after zygote collection from Padi6Null and WT mice. Number of zygotes: WT (n = 70), Padi6Null (n = 53). Rate of 2-cell/blastocyst = number of 2-cell/blastocyst/number of zygotes. In (f) and (h), n = number of oocytes analyzed, and data are presented as means ± s.d. P value were determined by unpaired, two-tailed t tests. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001; n.s., no significance. WT and Padi6Null differed significantly in blastocyst development (P < 0.0001), whereas all other comparisons were not significant. Oocyte maturation potential: GVBD, WT v.s. Padi6Null, P = 0.3744; MII, WT v.s. Padi6Null, P = 0.3627. Embryo development potential:2PN, WT v.s. Padi6Null, both groups were zygotes, P = 1.0; 2-cell, WT v.s. Padi6Null, P = 0.1977; blastocyst, WT v.s. Padi6Null, P < 0.0001.
