Int. J. Dev. Biol. 50: 3 - 15 (2006)
doi: 10.1387/ijdb.052095cs
© UBC Press

Head-tail patterning of the vertebrate embryo: one, two or many unresolved problems?

Claudio D. Stern1,*, Jeroen Charité2, Jacqueline Deschamps3, Denis Duboule4, Anthony J. Durston3, Marie Kmita4, Jean-François Nicolas5, Isabel Palmeirim6, Jim C. Smith7 and Lewis Wolpert1

European Union Network of Excellence "Cells into Organs". 1Department of Anatomy & Developmental Biology, University College London, U.K., 2Department of Cell Biology and Genetics, Erasmus University Rotterdam, The Netherlands, 3Hubrecht Laboratory / NIOB, Utrecht, The Netherlands, 4Département de Biologie Animale, Université de Genève, Switzerland, 5Unité de Biologie Moléculaire du Développement, Institut Pasteur, Paris, France, 6Escola de Ciências da Saúde/Instituto de Investigação em Ciências da Vida e Saúde, Universidade do Minho, Braga, Portugal and 7Wellcome/CR-UK Gurdon Institute for Cancer and Developmental Biology, Cambridge, U.K.

ABSTRACT When, where and how is the head-tail axis of the embryo set up during development? These are such fundamental and intensely studied questions that one might expect them to have been answered long ago. Not so; we still understand very little about the cellular or molecular mechanisms that lead to the orderly arrangement of body elements along the head-tail axis in vertebrates. In this paper, we outline some of the major outstanding problems and controversies and try to identify some reasons why it has been so difficult to resolve this important issue.


antero-posterior axis, AVE, hypoblast, hox gene, homeobox gene, Spemann Organizer

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