Multisite dependency of an E3 ligase controls monoubiquitylation-dependent cell fate decisions
Abstract
Metazoan development depends on tightly regulated gene expression programs that instruct progenitor cells to adopt specialized fates. Recent work found that posttranslational modifications, such as monoubiquitylation, can determine cell fate also independently of effects on transcription, yet how monoubiquitylation is implemented during development is poorly understood. Here, we have identified a regulatory circuit that controls monoubiquitylation-dependent neural crest specification by the E3 ligase CUL3 and its substrate adaptor KBTBD8. We found that CUL3KBTBD8 monoubiquitylates its essential targets only after these have been phosphorylated in multiple motifs by CK2, a kinase whose levels gradually increase during embryogenesis. Its dependency on multisite phosphorylation allows CUL3KBTBD8 to convert the slow rise in embryonic CK2 into decisive recognition of ubiquitylation substrates, which in turn is essential for neural crest specification. We conclude that multisite dependency of an E3 ligase provides a powerful mechanism for switch-like cell fate transitions controlled by monoubiquitylation.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
Article and author information
Author details
Funding
Howard Hughes Medical Institute
- Michael Rape
- Regina Baur
National Institutes of Health (K99DE025314)
- Achim Werner
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Ivan Dikic, Goethe University Frankfurt, Germany
Version history
- Received: January 25, 2018
- Accepted: July 7, 2018
- Accepted Manuscript published: July 12, 2018 (version 1)
- Accepted Manuscript updated: July 13, 2018 (version 2)
- Version of Record published: July 24, 2018 (version 3)
Copyright
© 2018, Rape 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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