Growth/differentiation factor 9 is a protein that in humans is encoded by the GDF9 gene.
Growth factors synthesized by ovarian somatic cells directly affect oocyte growth and function. Growth differentiation factor-9 (GDF9) is expressed in oocytes and is thought to be required for ovarian folliculogenesis. GDF9 is a member of the transforming growth factor-beta (TGFβ) superfamily.
Growth differentiation factor 9 (GDF9) is an oocyte derived growth factor in the transforming growth factor ß (TGF-ß) superfamily. It is highly expressed in the oocyte and has a pivotal influence on the surrounding somatic cells, particularly granulosa, cumulus and theca cells. Paracrine interactions between the developing oocyte and its surrounding follicular cells is essential for the correct progression of both the follicle and the oocyte. GDF9 is essential for the overall process of folliculogenesis, oogenesis and ovulation and thus plays a major role in female fertility.