Mechanisms leading to cortical reaction in the mammalian egg

Abnormal Fertilization Is Responsible for Reduced Fecundity Following Thiram-Induced Ovulatory Delay in the Rat1

“…Furthermore, although exocytosis is a very rapid process that follows the initial intracellular calcium rise, the dispersal of the CG material over the cell surface is relatively slow [34,35]. Raz et al [33] suggest that after the exocytotic process, rearrangement of the cortical granule exudate takes place on the plasma membrane, resulting in patches of cortical granule material. Based on these reports, we suggest that the increased aggregation (type III) in the delayed zygotes may be indicative of an advancement of this process, resulting in a less effective block to polyspermy at the level of the zona pellucida or oolemma.…”

“…Following CLSM examination of the LCA-stained zygotes in the present study, we observed a significant difference in distribution and staining intensity between the control (types I and II) and the delayed (primarily type III) zygote, suggesting that cortical granule exocytosis or formation of the cortical granule envelope may be altered. The appearance of the delayed zygote exudate, with more numerous aggregates than the controls, seems to correspond to a more advanced stage of fertilization that has been observed previously in rat fertilized eggs [33]. For example, Raz et al [33] showed that in fertilized eggs at the early stages of sperm decondensation, the CG exudate is visible as evenly distributed spots, whereas at later stages (i.e., when sperm decondensation was already completed or the pronuclear stage), cortical granule exudate appears as patchy aggregates scattered on the plasma membrane surface.…”

“…The appearance of the delayed zygote exudate, with more numerous aggregates than the controls, seems to correspond to a more advanced stage of fertilization that has been observed previously in rat fertilized eggs [33]. For example, Raz et al [33] showed that in fertilized eggs at the early stages of sperm decondensation, the CG exudate is visible as evenly distributed spots, whereas at later stages (i.e., when sperm decondensation was already completed or the pronuclear stage), cortical granule exudate appears as patchy aggregates scattered on the plasma membrane surface. Furthermore, although exocytosis is a very rapid process that follows the initial intracellular calcium rise, the dispersal of the CG material over the cell surface is relatively slow [34,35].…”

Compensatory endocytosis occurs after cortical granule exocytosis in mouse eggs

“…As a first step toward the study and characterization of CE in mouse eggs, we established a detection system to analyze the reincorporation of the CG membrane into the cytoplasm. For this purpose, we took advantage of the ability of LCA (Lens culinaris agglutinin) to tag exocytosed CG material in activated eggs (Raz, Skutelsky, Amihai, Hammel, & Shalgi, 1998). In this way, we could incubate living cells with labeled LCA and follow the labeling fate after exocytosis.…”

Effect of Vitrification of Feline Ovarian Cortex on Follicular and Oocyte Quality and Competence

“…Actin microfilaments together with microtubules are strictly involved in the oocyte maturation process, and their integrity is essential for proper progression through meiosis (Raz et al. 1998; Sun et al.…”