Extended Data Fig. 2: Piwil1-deficient oocytes show no obvious phenotypic abnormality but lack developmental competence for early embryos.
From: The piRNA pathway is essential for generating functional oocytes in golden hamsters
(a) PAS staining of wild type and Piwil1m1/m1 ovarian sections. (b) The average numbers of ovulated oocytes collected from wild-type and Piwil1m1/m1 females, as determined by a superovulation assay. Data are presented as mean values ± s.e.m. p-value = 0.2 by unpaired two-tailed t-test (n = 10 superovulated golden hamsters per group). (c) Immunofluorescence staining of the MII oocytes and early embryos using Actin- and Tubulin-specific antibodies. Nuclei were stained with DAPI. The results show normal morphology of spindles in Piwil1-deficient MII oocytes and the absence of the microtubule bridge (white arrow) in maternal Piwil1-deficient embryos. Piwil1m1/m1 indicates Piwil1-deficient oocytes or maternal Piwil1-deficient embryos. (d) Representative images of in vitro cultured embryos obtained from wild-type and Piwil1m1/m1 oocytes fertilized in vivo with wild-type sperm at 9, 33, 44, and 52 h.p.e.a. Red arrows, pronuclei. (e) Representative images of embryos collected from the oviducts of wild-type and Piwil1m2/m2 females at 52 h.p.e.a. The assays in a and c-d were performed twice, with similar results obtained. Statistical data are provided in the source data.
