Fig. 5. Actin filament formation during cortical granule translocation. Actin filaments were visualized and inferred by phalloidin staining followed by immunolabeling for cortical granules. Shown are early (A), mid- (B) and full- (C) sized oocytes, which have predominantly cortical actin labeling (oocyte in C is slightly compressed to better reveal the germinal vesicle). As oocytes begin meiotic maturation (D,E), the cortical granules move toward the cortex, the germinal vesicle becomes decidedly asymmetrical and phalloidin positive. The germinal vesicle then breaks down and matures to a haploid nucleus, while the cortical granules complete formation of the monolayer at the cortex. Although we can not detect individual microfilament bundles, cortical granule translocation coincides with microfilament formation in the germinal vesicle. Scale bar: 25 µm.

Return to article