Interaction between growing oocytes and granulosa cells in vitro

[摘要] Background: Oocyte growth is accompanied by follicular development in mammalian ovaries. Since the discovery of two oocyte‐derived factors, growth differentiation factor 9 (GDF9), and bone morphogenetic protein 15 (BMP15), knowledge of the bi‐ directional communication between oocytes and granulosa cells for ovarian function and fertility has been accumulated. In addition, the growth culture system of oocytes has been improved, further promoting the studies on the communication between oocytes and granulosa cells in vitro. Methods: We provide an overview of the role of granulosa cells in oocyte growth and the role of oocytes in follicular development along with our recent findings in culture experiments of bovine growing oocytes. Main findings: Granulosa cells supply nutrients and metabolites through gap junc‐ tions to oocytes and secrete paracrine signals to regulate oocytes. Oocytes regu‐ late granulosa cell proliferation and differentiation and induce antrum formation via GDF9 and BMP15. Conclusion: Oocytes actively participate in various aspects of follicular development, including antrum formation via the oocyte‐derived factors GDF9 and BMP15, whose synthesis is probably regulated by granulosa cells. In vitro studies will reveal the pre‐ cise communication loop between oocytes and granulosa cells that facilitates the coordinated development of oocytes and granulosa cells in the follicles.

[学科分类] 工业工程学

[关键词] BMP15;bovine oocyte;follicular antrum;GDF9;granulosa cell;transzonal projection