Fig. 3. Biochemical analysis for identification of CD9 and CD81 in the extracellular region of an oocyte.

(A) Experimental flow. A total of 40 oocytes were collected from oviducts of superovulated female mice, and cumulus cells were removed from oocytes by treatment with hyaluronidase. The ZP was removed from oocytes by treatment with collagenase. Extracellular components containing PVS and ZP and denuded oocytes were then subjected to immunoblotting together with epididymal sperm (1.5×10³). (B) Immunoblotting using anti-CD9 and anti-CD81.