DAZL mediates a broad translational program regulating expansion and differentiation of spermatogonial progenitors
Abstract
Fertility across metazoa requires the germline-specific DAZ family of RNA-binding proteins. Here we examine whether DAZL directly regulates progenitor spermatogonia using a conditional genetic mouse model and in vivo biochemical approaches combined with chemical synchronization of spermatogenesis. We find that the absence of Dazl impairs both expansion and differentiation of the spermatogonial progenitor population. In undifferentiated spermatogonia, DAZL binds the 3' UTRs of ~2,500 protein-coding genes. Some targets are known regulators of spermatogonial proliferation and differentiation while others are broadly expressed, dosage-sensitive factors that control transcription and RNA metabolism. DAZL binds 3' UTR sites conserved across vertebrates at a UGUU(U/A) motif. By assessing ribosome occupancy in undifferentiated spermatogonia, we find that DAZL increases translation of its targets. In total, DAZL orchestrates a broad translational program that amplifies protein levels of key spermatogonial and gene regulatory factors to promote the expansion and differentiation of progenitor spermatogonia.
Data availability
All sequencing data generated in this study are available at NCBI Gene Expression Omnibus accession number GSE145177
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Gene expression in Pou5f1:EGFP-positive spermatogonia from Dazl conditional knockout and control malesNCBI Gene Expression Omnibus (GEO), GSE144919.
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Gene expression in undifferentiated spermatogoniaNCBI Gene Expression Omnibus (GEO), GSE144923.
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DAZL targets in undifferentiated spermatogoniaNCBI Gene Expression Omnibus (GEO), GSE144920.
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Translational profiling in undifferentiated spermatogoniaNCBI Gene Expression Omnibus (GEO), GSE144922.
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DAZL mediates a broad translational program regulating expansion and differentiation of spermatogonial progenitorsNCBI Gene Expression Omnibus (GEO), GSE145177.
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RNA-seq in spermatogonia from PRC1ctrl and dKO miceNCBI Gene Expression Omnibus (GEO), GSE102783.
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Analysis of gene expression in populations of adult undifferentiated spermatogoniaNCBI Gene Expression Omnibus (GEO), GSE107124.
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Dazl maintains proliferating germ cells through a network of polyA-proximal mRNA interactions [P6 iCLIP]NCBI Gene Expression Omnibus (GEO), GSE108183.
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Conservation, acquisition, and functional impact of sex-biased gene expression in mammalian tissuesNCBI Gene Expression Omnibus (GEO), GSE125483.
Article and author information
Author details
Funding
Howard Hughes Medical Institute (Page laboratory)
- David C Page
Lalor Foundation (Postdoctoral fellowship)
- Maria M Mikedis
Eunice Kennedy Shriver National Institute of Child Health and Human Development (F32HD093391)
- Maria M Mikedis
National Natural Science Foundation of China (81471507)
- Yuting Fan
National Key Research and Development Program of China (2017YFC1001600)
- Yuting Fan
Hope Funds for Cancer Research (HFCR-15-06-06)
- Peter K Nicholls
National Health and Medical Research Council (GNT1053776)
- Peter K Nicholls
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All experiments involving mice were performed in accordance with the guidelines of the Massachusetts Institute of Technology (MIT) Division of Comparative Medicine, which is overseen by MIT's Institutional Animal Care and Use Committee (IACUC). The animal care program at MIT/Whitehead Institute is accredited by the Association for Assessment and Accreditation of Laboratory Animal Care, International (AAALAC), and meets or exceeds the standards of AAALAC as detailed in the Guide for the Care and Use of Laboratory Animals. The MIT IACUC approved this research (no. 0617-059-20).
Reviewing Editor
- Moira K O'Bryan, Monash University, Australia
Version history
- Received: March 2, 2020
- Accepted: July 20, 2020
- Accepted Manuscript published: July 20, 2020 (version 1)
- Version of Record published: August 24, 2020 (version 2)
Copyright
© 2020, Mikedis 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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