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

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend 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 Borchers, A. Articles by Wedlich, D. Search for Related Content PubMed PubMed Citation Articles by Borchers, A. Articles by Wedlich, D. Social Bookmarking                         What's this?

Xenopus cadherin-11 restrains cranial neural crest migration and influences neural crest specification

¹ Department of Genetics, Stanford University, Stanford, CA 94305-5120, USA
² Department of Biochemistry, University of Ulm, Germany
^* Author for correspondence at present address: Institute of Zoology II, University Karlsruhe (e-mail: doris.wedlich{at}zi2.uni-karlsruhe.de

Accepted 21 May 2001

Cranial neural crest (CNC) cells migrate extensively, typically in a pattern of cell streams. In Xenopus, these cells express the adhesion molecule Xcadherin-11 (Xcad-11) as they begin to emigrate from the neural fold. In order to study the function of this molecule, we have overexpressed wild-type Xcad-11 as well as Xcad-11 mutants with cytoplasmic (cXcad-11) or extracellular (eXcad-11) deletions. Green fluorescent protein (GFP) was used to mark injected cells. We then transplanted parts of the fluorescent CNC at the premigratory stage into non-injected host embryos. This altered not only migration, but also the expression of neural crest markers.

Migration of transplanted cranial neural crest cells was blocked when full-length Xcad-11 or its mutant lacking the ß-catenin-binding site (cXcad-11) was overexpressed. In addition, the expression of neural crest markers (AP-2, Snail and twist) diminished within the first four hours after grafting, and disappeared completely after 18 hours. Instead, these grafts expressed neural markers (2G9, nrp-1 and N-Tubulin). ß-catenin co-expression, heterotopic transplantation of CNC cells into the pharyngeal pouch area or both in combination failed to prevent neural differentiation of the grafts.

By contrast, eXcad-11 overexpression resulted in premature emigration of cells from the transplants. The AP-2 and Snail patterns remained unaffected in these migrating grafts, while twist expression was strongly reduced. Co-expression of eXcad-11 and ß-catenin was able to rescue the loss of twist expression, indicating that Wnt/ß-catenin signalling is required to maintain twist expression during migration.

These results show that migration is a prerequisite for neural crest differentiation. Endogenous Xcad-11 delays CNC migration. Xcad-11 expression must, however, be balanced, as overexpression prevents migration and leads to neural marker expression. Although Wnt/ß-catenin signalling is required to sustain twist expression during migration, it is not sufficient to block neural differentiation in non-migrating grafts.

Key words: Cadherin, Neural crest, Migration, Xenopus

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

This article has been cited by other articles:

				J. Kashef, A. Kohler, S. Kuriyama, D. Alfandari, R. Mayor, and D. Wedlich Cadherin-11 regulates protrusive activity in Xenopus cranial neural crest cells upstream of Trio and the small GTPases Genes & Dev., June 15, 2009; 23(12): 1393 - 1398. [Abstract] [Full Text] [PDF]

				C. McCusker, H. Cousin, R. Neuner, and D. Alfandari Extracellular Cleavage of Cadherin-11 by ADAM Metalloproteases Is Essential for Xenopus Cranial Neural Crest Cell Migration Mol. Biol. Cell, January 1, 2009; 20(1): 78 - 89. [Abstract] [Full Text] [PDF]

				I. Shnitsar and A. Borchers PTK7 recruits dsh to regulate neural crest migration Development, December 15, 2008; 135(24): 4015 - 4024. [Abstract] [Full Text] [PDF]