Fig. 6. Effect of over-expressing various PKC constructs on cortical granule lectin secretion from oocytes. Individual stage VI oocytes were injected with cRNA encoding wild-type (WT) or constitutively active (CA) PKC eta or delta. After incubation for 20 hours, the fluid surrounding each oocyte was collected for detection of released cgl (A). The oocytes were extracted for immunoblot analysis to verify the expression of PKC eta or delta (B). Under the conditions of immunoblot exposure in (B), endogenous expression of PKC eta or delta was essentially undetectable. Densitometric analysis revealed that injected oocytes expressed more than 50 times the endogenous level of each PKC isoform. Endogenous expression of these proteins is documented in Fig. 5.