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Updated: Jun 12, 2026

Methods for Studying Uterine Contributions to Pregnancy Establishment in an Ovariectomized Mouse Model
Published on: April 7, 2023
Conservation of progesterone hormone function in invertebrate reproduction
E Paige Stout1, James J La Clair, Terry W Snell
1School of Chemistry and Biochemistry and School of Biology, Georgia Institute of Technology, Atlanta, GA 30332, USA.
Abstract:
Steroids play fundamental roles regulating mammalian reproduction and development. Although sex steroids and their receptors are well characterized in vertebrates and several arthropod invertebrates, little is known about the hormones and receptors regulating reproduction in other invertebrate species. Evolutionary insights into ancient endocrine pathways can be gained by elucidating the hormones and receptors functioning in invertebrate reproduction. Using a combination of genomic analyses, receptor imaging, ligand identification, target elucidation, and exploration of function through receptor knockdown, we now show that comparable progesterone chemoreception exists in the invertebrate monogonont rotifer Brachionus manjavacas, suggesting an ancient origin of the signal transduction systems commonly associated with the development and integration of sexual behavior in mammals.
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