The alternative regenerative strategy of bearded dragon unveils the key processes underlying vertebrate tooth renewal
Abstract
Deep understanding of tooth regeneration is hampered by the lack of lifelong replacing oral dentition in most conventional models. Here, we show that the bearded dragon, one of the rare vertebrate species with both polyphyodont and monophyodont teeth, constitutes a key model for filling this gap, allowing direct comparison of extreme dentition types. Our developmental and high-throughput transcriptomic data of microdissected dental cells unveils the critical importance of successional dental lamina patterning, in addition to maintenance, for vertebrate tooth renewal. This patterning process happens at various levels, including directional growth but also gene expression levels, dynamics, and regionalization, and involves a large number of yet uncharacterized dental genes. Furthermore, the alternative renewal mechanism of bearded dragon dentition, with dual location of slow-cycling cells, demonstrates the importance of cell migration and functional specialization of putative epithelial stem/progenitor niches in tissue regeneration, while expanding the diversity of dental replacement strategies in vertebrates.
Data availability
All Illumina reads have been deposited on Dryad Digital Repository under the link https://datadryad.org/review?doi=doi:10.5061/dryad.k66jn2s. Primers used for qPCR and ISH probes are available in the Key Resources Table. All other data generated or analyzed during this study are included in the manuscript and Supplementary File 1.
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Data from: The alternative regenerative strategy of bearded dragon unveils the key processes underlying vertebrate tooth renewalDryad Digital Repository, doi:10.5061/dryad.k66jn2s.
Article and author information
Author details
Funding
Suomen Akatemia
- Nicolas Di-Poi
Suomen Akatemia
- Imran Khan
Integrative Life Science Doctoral Program
- Lotta Salomies
Helsingin Yliopisto
- Nicolas Di-Poi
Biocemtrum Helsinki
- Nicolas Di-Poi
Institute of biotechnology
- Nicolas Di-Poi
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Karen E Sears, University of California, Los Angeles, United States
Ethics
Animal experimentation: All reptile captive breedings and experiments were approved by the Laboratory Animal Centre (LAC) of the University of Helsinki and/or the National Animal Experiment Board (ELLA) in Finland (license numbers ESLH-2007-07445/ym-23, ESAVI/7484/04.10.07/2016, and ESAVI/13139/04.10.05/2017).
Version history
- Received: April 15, 2019
- Accepted: August 16, 2019
- Accepted Manuscript published: August 16, 2019 (version 1)
- Version of Record published: September 13, 2019 (version 2)
Copyright
© 2019, Salomies 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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