Molecular make-up of the human adult ovary

Abstract Functional ovarian cells are essential for human fertility. In the adult ovary, different cell types ensure ovary homeostasis, enable hormonal production and support oocyte maturation. Hence, the ovary is a complex and highly dynamic organ composed of a great diversity of cell types, many still uncharacterized. The use of single-cell RNA sequencing technologies on human ovarian tissue is starting to unravel the molecular signature of the cells present in the ovary, highlighting dramatic changes in gene expression during follicular growth and regression. This knowledge will ultimately provide insights in female fertility and associated-reproductive diseases and will allow the optimization of humans-based disease models and in vitro gametogenesis protocols.