Degradation of actin nucleators affects cortical polarity of aged mouse oocytes

Objective: To investigate the molecular mechanism of mouse oocyte polarity loss during aging. Design: Experimental study. Setting: Academic basic research laboratory. Animal(s): Mice. Intervention(s): Oocytes were collected 16 hours after injection of hCG and cultured in M16 medium for an additional 14 hours with or without caffeine. Main Outcome Measure(s): Expression and localizations of actin nucleators actin-related protein 2/3 complex, JMY, and WAVE2 were examined by immunofluorescence staining, and their messenger RNA levels were examined by real-time reverse transcription–polymerase chain reaction. Result(s): The protein and messenger RNA levels of actin-related protein 2/3 complex, JMY, and WAVE2 were decreased in aged oocytes, but the levels were normal in caffeine-treated aged oocytes. Conclusion(s): Our data indicated that the loss of oocyte polarity may be due to the degradation of actin nucleators in aged oocytes. [Copyright &y& Elsevier]