spacer gif spacer gif spacer gif spacer gif ARCHIVE ANNOUNCEMENT! spacer gif
QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

First published online October 26, 2007
doi: 10.1242/10.1242/dev.010850

Development 134, 4023-4032 (2007)
Published by The Company of Biologists 2007
This Article
Right arrow Figures Only
Right arrow Full Text
Right arrow Full Text (PDF)
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 Similar articles in PubMed
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 Rothbächer, U.
Right arrow Articles by Lemaire, P.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Rothbächer, U.
Right arrow Articles by Lemaire, P.

A combinatorial code of maternal GATA, Ets and ß-catenin-TCF transcription factors specifies and patterns the early ascidian ectoderm

Ute Rothbächer*,{dagger}, Vincent Bertrand*,{ddagger}, Clement Lamy and Patrick Lemaire{dagger}

Institut de Biologie du Développement de Marseille Luminy (IBDML), CNRS-UMR6216/Université de la Méditerranée Aix-Marseille, F-13288 Marseille Cedex 9, France.

{dagger} Authors for correspondence (e-mails: rothbach{at}ibdml.univ-mrs.fr; lemaire{at}ibdml.univ-mrs.fr)

Accepted 23 August 2007

Our understanding of the maternal factors that initiate early chordate development, and of their direct zygotic targets, is still fragmentary. A molecular cascade is emerging for the mesendoderm, but less is known about the ectoderm, giving rise to epidermis and nervous tissue. Our cis-regulatory analysis surprisingly places the maternal transcription factor Ci-GATAa (GATA4/5/6) at the top of the ectodermal regulatory network in ascidians. Initially distributed throughout the embryo, Ci-GATAa activity is progressively repressed in vegetal territories by accumulating maternal ß-catenin. Once restricted to the animal hemisphere, Ci-GATAa directly activates two types of zygotic ectodermal genes. First, Ci-fog is activated from the 8-cell stage throughout the ectoderm, then Ci-otx is turned on from the 32-cell stage in neural precursors only. Whereas the enhancers of both genes contain critical and interchangeable GATA sites, their distinct patterns of activation stem from the additional presence of two Ets sites in the Ci-otx enhancer. Initially characterized as activating elements in the neural lineages, these Ets sites additionally act as repressors in non-neural lineages, and restrict GATA-mediated activation of Ci-otx. We thus identify a precise combinatorial code of maternal factors responsible for zygotic onset of a chordate ectodermal genetic program.

Key words: Ectoderm, Ciona intestinalis, Ascidian, GATA, Ets, ß-catenin


Related articles in Development:

Gene regulatory networks: maternal code deciphered

Development 2007 134: e2203. [Full Text]  





© The Company of Biologists Ltd 2007