The follicle epithelium in the Drosophila ovary is maintained by a small number of stem cells
Abstract
The follicle stem cells (FSCs) in the Drosophila ovary are an important experimental model for the study of epithelial stem cell biology. Although decades of research support the conclusion that there are two FSCs per ovariole, a recent study used a novel clonal marking system to conclude that there are 15-16 FSCs per ovariole. We performed clonal analysis using both this novel clonal marking system and standard clonal marking systems, and identified several problems that may have contributed to the overestimate of FSC number. In addition, we developed new methods for accurately measuring clone size, and found that FSC clones produce, on average, half of the follicle cells in each ovariole. Our findings provide strong independent support for the conclusion that there are typically two active FSCs per ovariole, though they are consistent with up to four FSCs per germarium.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for Figures 1-5.
Article and author information
Author details
Funding
National Institutes of Health (GM097158)
- Todd G Nystul
National Institutes of Health (GM097158)
- Jocelyne Fadiga
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Yukiko M Yamashita, University of Michigan, United States
Publication history
- Received: June 5, 2019
- Accepted: December 17, 2019
- Accepted Manuscript published: December 18, 2019 (version 1)
- Version of Record published: January 7, 2020 (version 2)
Copyright
© 2019, Fadiga & Nystul
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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