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Updated: Jul 4, 2026
11:13
Indirect Immunofluorescence on Frozen Sections of Mouse Mammary Gland
Published on: December 1, 2015
Progesterone signaling in mammary gland development
O M Conneely1, B Mulac-Jericevic, R Arnett-Mansfield
1Department of Molecular and Cellular Biology, Baylor College of Medicine, One Baylor Plaza, 77030 Houston, USA. orlac@bcm.tmc.edu
Ernst Schering Foundation Symposium Proceedings
|June 11, 2008
Summary
Progesterone and prolactin (PRL) hormones are crucial for mammary gland development during pregnancy. Progesterone primes the mammary epithelium for PRL response, enabling milk-producing lobule formation.
Area of Science:
- Reproductive Biology
- Developmental Biology
- Endocrinology
Background:
- Mammary gland development involves extensive epithelial remodeling during pregnancy.
- This process is regulated by progesterone and prolactin (PRL) signaling.
- Disruption of these hormone receptors impairs alveologenesis.
Purpose of the Study:
- To identify progesterone receptor (PR)- and PRL-dependent signaling pathways in mammary gland remodeling.
- To elucidate the roles of downstream genes in mediating hormone effects during pregnancy-induced mammary gland development.
- To understand the interplay between progesterone and prolactin signaling.
Main Methods:
- Gene array analysis to identify PR- and PRL-dependent genes.
- Genetic mouse models (e.g., progesterone receptor-null mice) to study gene function.
- Analysis of gene expression changes in mammary glands.
Main Results:
- Progesterone signaling induces mammary epithelial PRL receptors, priming the epithelium for PRL response.
- PR-activated genes include those regulating epithelial proliferation, survival, cell fate, and gap junction formation.
- Two PR isoforms (PR-A and PR-B) show overlapping yet distinct regulatory functions.
Conclusions:
- Progesterone and prolactin signaling converge to regulate mammary gland alveologenesis.
- PR signaling orchestrates key cellular processes essential for functional mammary gland development.
- Understanding these pathways is vital for reproductive biology and endocrinology research.
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