spacer gif spacer gif spacer gif spacer gif spacer gif
QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

First published online March 6, 2009
doi: 10.1242/10.1242/dev.032300

Development 136, 1179-1189 (2009)
Published by The Company of Biologists 2009
This Article
Right arrow Figures Only
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Supplementary Material
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Related articles in Development
Right arrow Similar articles in this journal
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Wei, Z.
Right arrow Articles by Angerer, L. M.
Right arrow Search for Related Content
PubMed
Right arrow Articles by Wei, Z.
Right arrow Articles by Angerer, L. M.
Social Bookmarking
Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati   Add to Twitter  
What's this?

The sea urchin animal pole domain is a Six3-dependent neurogenic patterning center

Zheng Wei, Junko Yaguchi*, Shunsuke Yaguchi*, Robert C. Angerer and Lynne M. Angerer{dagger}

National Institute for Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892, USA.

{dagger} Author for correspondence (e-mail: langerer{at}mail.nih.gov)

Accepted 29 January 2009

Two major signaling centers have been shown to control patterning of sea urchin embryos. Canonical Wnt signaling in vegetal blastomeres and Nodal signaling in presumptive oral ectoderm are necessary and sufficient to initiate patterning along the primary and secondary axes, respectively. Here we define and characterize a third patterning center, the animal pole domain (APD), which contains neurogenic ectoderm, and can oppose Wnt and Nodal signaling. The regulatory influence of the APD is normally restricted to the animal pole region, but can operate in most cells of the embryo because, in the absence of Wnt and Nodal, the APD expands throughout the embryo. We have identified many constituent APD regulatory genes expressed in the early blastula and have shown that expression of most of them requires Six3 function. Furthermore, Six3 is necessary for the differentiation of diverse cell types in the APD, including the neurogenic animal plate and immediately flanking ectoderm, indicating that it functions at or near the top of several APD gene regulatory networks. Remarkably, it is also sufficient to respecify the fates of cells in the rest of the embryo, generating an embryo consisting of a greatly expanded, but correctly patterned, APD. A fraction of the large group of Six3-dependent regulatory proteins are orthologous to those expressed in the vertebrate forebrain, suggesting that they controlled formation of the early neurogenic domain in the common deuterostome ancestor of echinoderms and vertebrates.

Key words: Microarray, Nodal, BMP2/4, Primary axis, Secondary axis, Canonical Wnt signaling, β-catenin, Gene expression profiling, Neural development, Transcription factor


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

Related articles in Development:

Throw a Six3 for neurogenesis

Development 2009 136: e703. [Full Text]  





© The Company of Biologists Ltd 2009