Molecular and endocrine determinants of oocyte competence

Fair, T

Mammalian female gametes are stored for many years in the ovaries in an inactive state until stimulated to grow. Activation of the resting follicle is initiated by the oocyte and requires a communication mechanism between the oocyte and the surrounding granulosa cells. Key molecular and morphological events that occur during oocyte and follicle growth and maturation include the establishment of a bi-directional communication system, granulosa cell proliferation and antrum formation, nucleolus activation and initiation of oocyte transcription, establishment of the maternal imprints and completion of the m eiotic maturation. Successful accomplishment of these events furnishes the oocyte with the competency to support fertilization and to sustain early embryo development and is reflected in the molecular signatures of the oocyte and the follicular granulosa cells. The current review will consider these events and highlight the molecular and endocrine factors associated with them.(AU)

1. follicle
2. progesterone
3. gene expression
4. egg