QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

First published online 28 January 2009
doi: 10.1242/dev.029017

This Article Figures Only Full Text Full Text (PDF) All Versions of this Article: dev.029017v1 136/5/771    most recent Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Related articles in Development Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Steventon, B. Articles by Mayor, R. Search for Related Content PubMed PubMed Citation Articles by Steventon, B. Articles by Mayor, R. Pubmed/NCBI databases Substance via MeSH Social Bookmarking                         What's this?

Differential requirements of BMP and Wnt signalling during gastrulation and neurulation define two steps in neural crest induction

Department of Cell and Developmental Biology, University College London, London WC1E 6BT, UK.

^* Author for correspondence (e-mail: r.mayor{at}ucl.ac.uk)

Accepted 30 December 2008

The neural crest is induced by a combination of secreted signals. Although previous models of neural crest induction have proposed a step-wise activation of these signals, the actual spatial and temporal requirement has not been analysed. Through analysing the role of the mesoderm we show for the first time that specification of neural crest requires two temporally and chemically different steps: first, an induction at the gastrula stage dependent on signals arising from the dorsolateral mesoderm; and second, a maintenance step at the neurula stage dependent on signals from tissues adjacent to the neural crest. By performing tissue recombination experiments and using specific inhibitors of different inductive signals, we show that the first inductive step requires Wnt activation and BMP inhibition, whereas the later maintenance step requires activation of both pathways. This change in BMP necessity from BMP inhibition at gastrula to BMP activation at neurula stages is further supported by the dynamic expression of BMP4 and its antagonists, and is confirmed by direct measurements of BMP activity in the neural crest cells. The differential requirements of BMP activity allow us to propose an explanation for apparently discrepant results between chick and frog experiments. The demonstration that Wnt signals are required for neural crest induction by mesoderm solves an additional long-standing controversy. Finally, our results emphasise the importance of considering the order of exposure to signals during an inductive event.

Key words: Neural crest induction, Mesoderm, Wnt, BMP, Slug, Sox2

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

Related articles in Development:

Neural crest does the two-step

Development 2009 136: e503. [Full Text]  

This article has been cited by other articles:

				B. Li, S. Kuriyama, M. Moreno, and R. Mayor The posteriorizing gene Gbx2 is a direct target of Wnt signalling and the earliest factor in neural crest induction Development, October 1, 2009; 136(19): 3267 - 3278. [Abstract] [Full Text] [PDF]