Fibroblast growth factor-9, a local regulator of ovarian function.

Fibroblast growth factor 9 (FGF9) is widely expressed in embryos and fetuses and has been shown to be involved in male sex determination, testicular cord formation, and Sertoli cell differentiation. Given its male gender bias, the ovary has not been reported to express FGF9, nor has a role in ovarian function been explored. We report here that FGF9 mRNA and protein are present in the rat ovary and provide evidence that supports a role for FGF9 in ovarian progesterone production.

Ovarian follicle populations of the rat express TGF-beta signalling pathways.

The transforming growth factor-beta (TGF-beta) superfamily comprises more than 40 members, classified on the basis of structural similarity. These factors elicit a diverse range of cellular responses in insects, nematodes and vertebrates, via serine/threonine kinase receptors and intracellular Smad proteins, which when activated mediate gene transcription. Some members of the superfamily, notably activin, TGF-beta, GDF-9 and the bone morphogenetic proteins have been shown to influence ovarian function.

Ovarian steroid receptors and their role in ovarian function.

The steroidogenic pathway within the ovary gives rise to progestins, androgens and oestrogens, all of which act via specific nuclear receptors to regulate reproductive function and maintain fertility. The precise role of oestrogen in the ovary remains to be elucidated, hence the data presented here which arises from studies designed to resolve this issue. Oestrogens signal via two receptor subtypes ERalpha and ERbeta, both of which are present in the ovary.

Expression and localization of activin receptors, Smads, and beta glycan to the postnatal rat ovary.

Despite understanding the molecular basis of activin/TGF beta and bone morphogenetic protein (BMP) signaling, this study is the first to characterize multiple, sequential elements of these pathways in the ovary concurrently. The expression of activin/BMP receptor, Smad, and beta glycan mRNAs by postnatal rat ovaries were investigated by real-time PCR. Activin/BMP receptors (ActRIA, ActRIB, ActRIIA, and ActRIIB), beta glycan, and Smad 1-8 mRNAs were expressed by the ovary.