Pituitary stem cells produce paracrine WNT signals to control the expansion of their descendant progenitor cells
Abstract
In response to physiological demand, the pituitary gland generates new hormone-secreting cells from committed progenitor cells throughout life. It remains unclear to what extent pituitary stem cells (PSCs), which uniquely express SOX2, contribute to pituitary growth and renewal. Moreover, neither the signals that drive proliferation nor their sources have been elucidated. We have used genetic approaches in the mouse, showing that the WNT pathway is essential for proliferation of all lineages in the gland. We reveal that SOX2+ stem cells are a key source of WNT ligands. By blocking secretion of WNTs from SOX2+ PSCs in vivo, we demonstrate that proliferation of neighbouring committed progenitor cells declines, demonstrating that progenitor multiplication depends on the paracrine WNT secretion from SOX2+ PSCs. Our results indicate that stem cells can hold additional roles in tissue expansion and homeostasis, acting as paracrine signalling centres to coordinate the proliferation of neighbouring cells.
Data availability
Sequencing data can be accessed through the following link: https://www.ncbi.nlm.nih.gov/bioproject/PRJNA421806
Article and author information
Author details
Funding
Medical Research Council (MR/L016729/1)
- Cynthia Lilian Andoniadou
Medical Research Council (MR/T012153/1)
- Cynthia Lilian Andoniadou
Deutsche Forschungsgemeinschaft (314061271 - TRR 205)
- Cynthia Lilian Andoniadou
Howard Hughes Medical Institute
- Roel Nusse
Agence Nationale de la Recherche (ANR-18-CE14-0017)
- Patrice Mollard
Fondation pour la Recherche Médicale (DEQ20150331732)
- Patrice Mollard
Lister Institute of Preventive Medicine
- Cynthia Lilian Andoniadou
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed under compliance of the Animals (Scientific Procedures) Act 1986, Home Office License (P5F0A1579) and KCL Biological Safety approval for project 'Function and Regulation of Pituitary Stem Cells in Mammals'
Copyright
© 2021, Russell et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Further reading
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