Wnt-and Glutamate-receptors orchestrate stem cell dynamics and asymmetric cell division
Abstract
The Wnt-pathway is part of a signalling network that regulates many aspects of cell biology. Recently we discovered crosstalk between AMPA/Kainate-type ionotropic glutamate receptors (iGluRs) and the Wnt-pathway during the initial Wnt3a-interaction at the cytonemes of mouse embryonic stem cells (ESCs). Here, we demonstrate that this crosstalk persists throughout the Wnt3a-response in ESCs. Both AMPA- and Kainate-receptors regulate early Wnt3a-recruitment, dynamics on the cell membrane, and orientation of the spindle towards a Wnt3a-source at mitosis. AMPA-receptors specifically are required for segregating cell fate components during Wnt3a-mediated asymmetric cell division (ACD). Using Wnt-pathway component knockout lines, we determine that Wnt co-receptor Lrp6 has particular functionality over Lrp5 in cytoneme formation, and in facilitating ACD. Both Lrp5 and 6, alongside pathway effector β-catenin act in concert to mediate the positioning of the dynamic interaction with, and spindle orientation to, a localized Wnt3a-source. Wnt-iGluR crosstalk may prove pervasive throughout embryonic and adult stem cell signalling.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
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Author details
Funding
Wellcome Trust (102513/Z/13/Z)
- Shukry J Habib
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Beate Maria Lichtenberger, Medical University of Vienna, Austria
Version history
- Received: June 8, 2020
- Accepted: May 21, 2021
- Accepted Manuscript published: May 24, 2021 (version 1)
- Accepted Manuscript updated: June 2, 2021 (version 2)
- Version of Record published: June 4, 2021 (version 3)
Copyright
© 2021, Junyent 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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