Oriented clonal cell dynamics enables accurate growth and shaping of vertebrate cartilage
Abstract
Cartilaginous structures are at the core of embryo growth and shaping before the bone forms. Here we report a novel principle of vertebrate cartilage growth that is based on introducing transversally-oriented clones into pre-existing cartilage. This mechanism of growth uncouples the lateral expansion of curved cartilaginous sheets from the control of cartilage thickness, a process which might be the evolutionary mechanism underlying adaptations of facial shape. In rod-shaped cartilage structures (Meckel, ribs and skeletal elements in developing limbs), the transverse integration of clonal columns determines the well-defined diameter and resulting rod-like morphology. We were able to alter cartilage shape by experimentally manipulating clonal geometries. Using in silico modeling, we discovered that anisotropic proliferation might explain cartilage bending and groove formation at the macro-scale.
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Author details
Funding
European Molecular Biology Organization (ALTF 216-2013)
- Marketa Kaucka
Svenska Sällskapet för Medicinsk Forskning
- Marketa Kaucka
Svenska Forskningsrådet Formas
- Andreas Hellander
- Phillip T Newton
- Andrei S Chagin
- Kaj Fried
- Igor Adameyko
Karolinska Institutet
- Phillip T Newton
- Andrei S Chagin
- Kaj Fried
- Igor Adameyko
Bertil Hållstens Forskningsstiftelse
- Igor Adameyko
Åke Wiberg Stiftelse
- Igor Adameyko
National Institutes of Health
- Andreas Hellander
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 animal (mouse) work has been approved and permitted by the Ethical Committee on Animal Experiments (Norra Djurförsöksetiska Nämd, ethical permit N226/15 and N5/14) and conducted according to The Swedish Animal Agency´s Provisions and Guidelines for Animal Experimentation recommendations.
Copyright
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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