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Adult Mouse Digit Amputation and Regeneration: A Simple Model to Investigate Mammalian Blastema Formation and Intramembranous Ossification
Published on: July 12, 2019
Mathematical modelling of digit specification by a sonic hedgehog gradient.
Thomas E Woolley1, Ruth E Baker, Cheryll Tickle
1Wolfson Centre for Mathematical Biology, Mathematical Institute, University of Oxford, Radcliffe Observatory Quarter, Oxford, United Kingdom; Oxford Centre for Collaborative Applied Mathematics, Mathematical Institute, University of Oxford, Oxford, United Kingdom.
A mathematical model explains chick digit development using a sonic hedgehog (Shh) gradient. This model extends to chick legs but not mouse limbs, suggesting additional mechanisms are needed for more complex limb development.
Area of Science:
- Developmental Biology
- Computational Biology
- Genetics
Background:
- Limb development is a classic model for pattern formation by morphogen gradients.
- Sonic hedgehog (Shh) is a key signaling molecule in limb patterning.
Purpose of the Study:
- To mathematically model chick wing digit specification by Shh.
- To assess the model's applicability to limbs with varying digit numbers.
Main Methods:
- Development of a mathematical model for Shh gradient-based digit specification.
- Testing the model's extension to chick leg and mouse limb development.
Main Results:
- The model successfully describes chick wing and leg digit identities.
- The model is not directly applicable to the five-digit mouse limb.
Conclusions:
- A classical morphogen gradient model suffices for three digits.
- Specifying more digits requires coupling to alternative processes like Shh-producing cells forming digits or adaptive cellular responses to Shh.
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