Extended Data Fig. 4: Lack of PIWI proteins in oocytes of PIWIL1- or PIWIL3-deficient golden hamsters.
a, Total lysates of 20 MII oocytes each from heterozygous mutant (w/m) and homozygous mutant (m/m) golden hamsters were subjected to western blotting. TUBB was used as the loading control. Spectra™ Multicolor Broad Range Protein Ladder (Thermo Fisher Scientific) was used as size marker. b, Immunological staining of PIWIL1- and PIWIL3-deficient ovaries with an anti‐PIWIL1 and PIWIL3 antibodies. The arrowheads in the mutants indicate the ovarian follicles. The zona pellucida fixed with paraformaldehyde showed autofluorescence. In particular, PIWIL1, which requires a long exposure time, has strong ring-shaped fluorescence both in the wild type and PIWIL1m/m. Scale bars = 50 µm. c, Ovarian sections from 8‐week‐old wild-type and PIWIL1- and PIWIL3-deficient golden hamsters. Hematoxylin and eosin‐stained ovarian sections of wild-type, PIWIL1- and PIWIL3-deficient golden hamsters. Scale bars = 200 µm. Note: By fixing PIWIs, the antigenicity is weakened. PIWIL1 antigenicity is particularly weak even after antigen retrieval treatment: therefore, the exposure time is long and the background of the zona pellucida becomes visible.
