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    

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 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 HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Janody, F.
Right arrow Articles by Dostatni, N.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Janody, F.
Right arrow Articles by Dostatni, N.
Development 128, 2281-2290 (2001)
© 2001 The Company of Biologists Limited

Two distinct domains of Bicoid mediate its transcriptional downregulation by the Torso pathway

Florence Janody1,*, Rachel Sturny1, Valérie Schaeffer2,{ddagger}, Yannick Azou1 and Nathalie Dostatni1,§,¶

1 Developmental Biology Institute of Marseille, Laboratoire de Génétique et Physiologie du Développement, Université de la Méditerrannée, Luminy, Case 907, 13288 Marseille Cedex 09, France
2 Department of Biology, New York University, 100 Washington Square East, New York, NY 10003, USA
* Present address: Skirball Institute of Biomolecular Medicine, 540 First Avenue, New York, NY 10016, USA
{ddagger} Present address: EMBL, Meyerhofstrasse 1, 69117 Heidelberg, Germany
§ Present address: UMR218, Curie Institute-Section of Research, Pavillon Pasteur, 26 rue d’Ulm, 75 248 Paris Cedex 05, France

¶Author for correspondence (e-mail: nathalie.dostatni{at}curie.fr)

Accepted March 27, 2001

The transcriptional activity of the Bicoid morphogen is directly downregulated by the Torso signal transduction cascade at the anterior pole of the Drosophila embryo. This regulation does not involve the homeodomain or direct phosphorylation of Bicoid. We analyse the transcriptional regulation of Bicoid in response to the Torso pathway, using Bicoid variants and fusion proteins between the Bicoid domains and the Gal4 DNA-binding domain. We show that Bicoid possesses three autonomous activation domains. Two of these domains, the serine/threonine-rich and the acidic domains, are downregulated by Torso, whereas the third activation domain, which is rich in glutamine, is not. The alanine-rich domain, previously described as an activation domain in vitro, has a repressive activity that is independent of Torso. Thus, Bicoid downregulation by Torso results from a competition between the glutamine-rich domain that is insensitive to Torso and the serine/threonine-rich and acidic activation domains downregulated by Torso. The alanine-rich domain contributes to this process indirectly by reducing the global activity of the protein and in particular the activity of the glutamine-rich domain that might otherwise prevent downregulation by Torso.

Key words: Bicoid morphogen, Homeodomain, Downregulation, Torso receptor tyrosine kinase, Drosophila




This article has been cited by other articles:


Home page
 DevelopmentHome page
C. Zhao, A. York, F. Yang, D. J. Forsthoefel, V. Dave, D. Fu, D. Zhang, M. S. Corado, S. Small, M. A. Seeger, et al.
The activity of the Drosophila morphogenetic protein Bicoid is inhibited by a domain located outside its homeodomain
Development, January 4, 2002; 129(7): 1669 - 1680.
[Abstract] [Full Text] [PDF]


© The Company of Biologists Ltd 2001