Sperm Proteasomes Degrade Sperm Receptor on the Egg Zona Pellucida during Mammalian Fertilization
Figure 6
Patterns of zona pellucida deposition and ZPC-ubiquitin colocalization in porcine ocyte-cumulus complexes isolated from small antral follicles.
(a, b) Accumulation of ZPC (gray) in ridges (arrowheads) adjacent to zona-adhering corona radiata cells (blue = nuclei stained with DAPI). (c-e) Colocalization of ZPC (red) and ubiquitin (green) in the zona pellucida (c, d) and in the cytoplasm of corona radiata cells (e); DNA was counterstained with DAPI (blue). Western blotting of ZPC protein in the isolated cumulus/corona cells from 60 oocyte cumulus complexes (lane 1), in 60 zona-free oocytes (lane 2) and in soluble zona proteins isolated from 60 oocytes (lane 3).