Chapter 9. Tinkering with Constraints in the Evolution of the Vertebrate Limb Anterior–Posterior Polarity

  1. Gregory Bock Organizer and
  2. Jamie Goode
  1. Denis Duboule,
  2. Basile Tarchini,
  3. Jozsef Zàkàny and
  4. Marie Kmita

Published Online: 11 JUN 2007

DOI: 10.1002/9780470319390.ch9

Tinkering: The Microevolution of Development: Novartis Foundation Symposium 284

Tinkering: The Microevolution of Development: Novartis Foundation Symposium 284

How to Cite

Duboule, D., Tarchini, B., Zàkàny, J. and Kmita, M. (2006) Tinkering with Constraints in the Evolution of the Vertebrate Limb Anterior–Posterior Polarity, in Tinkering: The Microevolution of Development: Novartis Foundation Symposium 284 (eds G. Bock and J. Goode), John Wiley & Sons, Ltd, Chichester, UK. doi: 10.1002/9780470319390.ch9

Author Information

  1. Department of Zoology and Animal Biology, and National Research Centre ‘Frontiers in Genetics’, University of Geneva, Sciences III, Quai Ernest Ansermet 30, 1211 Geneva 4, Switzerland

  1. Department of Biology, McGill University, 1205 Ave. Docteur Penfield, Montréal, Quebec, Canada

  2. Unité de Génétique et Développement, Institut de Recherches Cliniques de Montréal (IRCM), 110 avenue des Pins Ouest, H2W 1R7, Montréal Quebec, Canada

Publication History

  1. Published Online: 11 JUN 2007
  2. Published Print: 8 JUN 2006

Book Series:

  1. Novartis Foundation Symposia

Book Series Editors:

  1. Novartis Foundation

ISBN Information

Print ISBN: 9780470034293

Online ISBN: 9780470319390

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Keywords:

  • Hox genes in developing limbs;
  • Hox genes, Sonic hedgehog (Shh) and limb development;
  • HoxA and HoxD clusters for vertebrate limb development;
  • mechanisms of collinearity;
  • HoxD cluster (ELCR)

Summary

Genes belonging to both HoxA and HoxD clusters are required for proper vertebrate limb development. Mice lacking all, or parts of, Hoxa and Hoxd functions in forelimbs, as well as mice with a gain of function of these genes in the early limb bud, have helped us to understand functional and regulatory issues associated with these genes, such that, for example, the tight mechanistic interdependency that exists between the production of the limb and its anterior to posterior (AP) polarity. Our studies suggest that the evolutionary recruitment of Hox gene function into growing appendages was crucial to implement hedgehog signalling, subsequently leading to the distal extension of tetrapod appendages, with an already built-in AP polarity. We propose that this process results from the evolutionary co-option, in the developing limbs, of a particular regulatory mechanism (collinearity), which is necessary to pattern the developing trunk. This major regulatory constraint imposed a polarity to our limbs as the most parsimonious solution to grow appendages.