JNK signaling triggers spermatogonial dedifferentiation during chronic stress to maintain the germline stem cell pool in the Drosophila testis
Abstract
Exhaustion of stem cells is a hallmark of aging. In the Drosophila testis, dedifferentiated germline stem cells (GSCs) derived from spermatogonia increases during lifespan, leading to the model that dedifferentiation counteracts the decline of GSCs in aged males. To test this, we blocked dedifferentiation by mis-expressing the differentiation factor bag of marbles (bam) in spermatogonia while lineage-labeling these cells. Strikingly, blocking bam-lineage dedifferentiation under normal conditions in virgin males has no impact on the GSC pool. However, in mated males or challenging conditions, inhibiting bam-lineage dedifferentiation markedly reduced the number of GSCs and their ability to proliferate and differentiate. We find that bam-lineage derived GSCs have significantly higher proliferation rates than sibling GSCs in the same testis. We determined that Jun N-terminal kinase (JNK) activity is autonomously required for bam-lineage dedifferentiation. Overall, we show that dedifferentiation provides a mechanism to maintain the germline and ensure fertility under chronically stressful conditions.
Data availability
All data generated or analyzed during this study are included in the manuscript and supporting files. Source data files have been provided for Supplementary Files 1-3.
Article and author information
Author details
Funding
National Institute of General Medical Sciences (R01 GM085075)
- Erika A Bach
European Molecular Biology Organization
- Salvador C Herrera
Human Frontier Science Program (LT000529-2015)
- Salvador C Herrera
New York State Department of Health (NYSTEM N11G-292)
- Erika A Bach
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: February 20, 2018
- Accepted: July 6, 2018
- Accepted Manuscript published: July 9, 2018 (version 1)
- Version of Record published: August 1, 2018 (version 2)
Copyright
© 2018, Herrera & Bach
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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