The Role of Maternal Factors during the Oocyte-to-Embryo Transition in Mammals

During oocyte formation, a substantial number of maternal factors, encoded by MEGs (maternal effect genes), are synthesized and stored. These factors play crucial roles in various aspects of oocyte and early embryo development, including the synthesis and accumulation of maternal mRNAs, orderly arrangement of organelles, epigenetic reprogramming, egg activation after fertilization, initiation of zygotic genome activation, and clearance of maternal transcripts. This review presents a comprehensive analysis of the impact of maternal factors on key processes in mammalian oocyte and embryo development, while also discusses the regulation of expression and localization of these factors. Researches have demonstrated that variations in MEGs are associated with a range of adverse reproductive outcomes. In humans, these variants can result in infertility, and an increased risk of fetal structural defects and offspring with multilocus imprinting disorders. By in-depth studies of maternal factors and their regulatory mechanisms, this review can improve the understanding of the physiological processes of oocyte and early embryonic development. This knowledge has the potential to improve the accuracy of infertility diagnosis and treatment, as well as provides new strategies for the prevention of related diseases

CSTR: 32200.14.cjcb.2024.04.0008