Efficient differentiation of human primordial germ cells through geometric control reveals a key role for Nodal signaling
Abstract
Human primordial germ cells (hPGCs) form around the time of implantation and are the precursors of eggs and sperm. Many aspects of hPGC specification remain poorly understood because of the inaccessibility of the early postimplantation human embryo for study. Here we show that micropatterned human pluripotent stem cells (hPSCs) treated with BMP4 give rise to hPGC-like cells (hPGCLC) and use these as a quantitatively reproducible and simple in vitro model to interrogate this important developmental event. We characterize micropatterned hPSCs up to 96h and show that hPGCLC populations are stable and continue to mature. By perturbing signaling during hPGCLC differentiation, we identify a previously unappreciated role for Nodal signaling and find that the relative timing and duration of BMP and Nodal signaling are critical parameters controlling the number of hPGCLCs. We formulate a mathematical model for a network of cross-repressive fates driven by Nodal and BMP signaling which predicts the measured fate patterns after signaling perturbations. Finally, we show that hPSC colony size dictates the efficiency of hPGCLC specification, which led us to dramatically improve the efficiency of hPGCLC differentiation.
Data availability
All code for data analysis and model simulations is available on github.com/idse/PGCsscRNA-seq data have been deposited in GEO under accession number GSE182057.
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scRNA-seq of BMP-treated micropatterned hPSCs after 42hNCBI Gene Expression Omnibus, GSE182057.
Article and author information
Author details
Funding
Medical School, University of Michigan (startup)
- Kyoung Jo
- Seth Teague
- Bohan Chen
- Hina Aftab Khan
- Emily Freeburne
- Hunter Li
- Bolin Li
- Ran Ran
- Idse Heemskerk
ETH Zürich Foundation (Branco Weiss Fellowship)
- Hina Aftab Khan
- Idse Heemskerk
National Institute of General Medical Sciences (R35 GM138346)
- Seth Teague
- Bohan Chen
Medical School, University of Michigan (Pioneer Fellowship)
- Kyoung Jo
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Martin Pera, The Jackson Laboratory, United States
Publication history
- Preprint posted: August 5, 2021 (view preprint)
- Received: August 5, 2021
- Accepted: April 7, 2022
- Accepted Manuscript published: April 8, 2022 (version 1)
- Version of Record published: May 13, 2022 (version 2)
Copyright
© 2022, Jo 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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