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Updated: Aug 16, 2026

A Modified Co-Culture System for Understanding Granulosa-Theca Cell Interactions in the Bovine Ovary
Published on: September 19, 2025
Bone morphogenetic protein 5 expression in the rat ovary: biological effects on granulosa cell proliferation and
Alice Pierre1, Claudine Pisselet, Joelle Dupont
1Physiologie de la Reproduction et des Comportements, UMR 6175 INRA-CNRS-Université F. Rabelais de Tours Haras Nationaux, 37380 Nouzilly, France.
Abstract:
Recently, the role of several elements of the bone morphogenetic protein (BMP) family has been studied in the ovary, some of them being crucial for ovarian function. In the present work, we have studied bone morphogenetic protein 5 (BMP5) expression and its biological role in the rat ovary. BMP5 is expressed by rat granulosa cells (GCs) and exerts specific biological effects on proliferation and steroidogenesis of these cells in an autocrine manner. These effects were shown to be associated with an increase in cyclin D2 protein level and a decrease in steroidogenic acute regulatory (StAR) protein expression in GCs in vitro. Ultimately, BMP5 actions were inhibited by follistatin. Overall, these data show that BMP5 is a novel element of the BMP family that might play a fully paracrine role in rodent ovarian folliculogenesis.
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