Nuclear receptor Ftz-f1 promotes follicle maturation and ovulation partly via bHLH/PAS transcription factor Sim
Abstract
The NR5A-family nuclear receptors are highly conserved and function within the somatic follicle cells of the ovary to regulate folliculogenesis and ovulation in mammals; however, their roles in Drosophila ovaries are largely unknown. Here, we discover that Ftz-f1, one of the NR5A nuclear receptors in Drosophila, is transiently induced in follicle cells in late stages of oogenesis via ecdysteroid signaling. Genetic disruption of Ftz-f1 expression prevents follicle cell differentiation into the final maturation stage, which leads to anovulation. In addition, we demonstrate that the bHLH/PAS transcription factor Single-minded (Sim) acts as a direct target of Ftz-f1 to promote follicle cell differentiation/maturation and that Ftz-f1's role in regulating Sim expression and follicle cell differentiation can be replaced by its mouse homolog steroidogenic factor 1 (mSF-1). Our work provides new insight into the regulation of follicle maturation in Drosophila and the conserved role of NR5A nuclear receptors in regulating folliculogenesis and ovulation.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. sequencing data have been deposited in SRA under BioProject ID PRJNA624186.
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Direct targets of Ftz-f1 in Drosophila follicle cellsNCBI Sequence Read Archive, PRJNA624186.
Article and author information
Author details
Funding
Eunice Kennedy Shriver National Institute of Child Health and Human Development (R01-HD086175)
- Jianjun Sun
Bill and Melinda Gates Foundation (Opp1160858)
- Jianjun Sun
Bill and Melinda Gates Foundation (Opp1203047)
- Jianjun Sun
Eunice Kennedy Shriver National Institute of Child Health and Human Development (R01-HD097206)
- Jianjun Sun
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2020, Knapp 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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