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 November 11, 2004
doi: 10.1242/10.1242/dev.01515

Development 131, 5897-5907 (2004)
Published by The Company of Biologists 2004
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 HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Riechmann, V.
Right arrow Articles by Ephrussi, A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Riechmann, V.
Right arrow Articles by Ephrussi, A.

Par-1 regulates bicoid mRNA localisation by phosphorylating Exuperantia

Veit Riechmann* and Anne Ephrussi{dagger}

European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany

{dagger} Author for correspondence (e-mail: ephrussi{at}embl-heidelberg.de)

Accepted 29 September 2004

The Ser/Thr kinase Par-1 is required for cell polarisation in diverse organisms such as yeast, worms, flies and mammals. During Drosophila oogenesis, Par-1 is required for several polarisation events, including localisation of the anterior determinant bicoid. To elucidate the molecular pathways triggered by Par-1, we have performed a genome-wide, high-throughput screen for Par-1 targets. Among the targets identified in this screen was Exuperantia (Exu), a mediator of bicoid mRNA localisation. We show that Exu is a phosphoprotein whose phosphorylation is dependent on Par-1 in vitro and in vivo. We identify two motifs in Exu that are phosphorylated by Par-1, and show that their mutation abolishes bicoid mRNA localisation during mid-oogenesis. Interestingly, exu mutants in which Exu phosphorylation is specifically affected can to some extent recover from these bicoid mRNA localisation defects during late oogenesis. These results demonstrate that Par-1 establishes polarity in the oocyte by activating a mediator of bicoid mRNA localisation. Furthermore, our analysis reveals two phases of Exu-dependent bicoid mRNA localisation: an early phase that is strictly dependent on Exu phosphorylation and a late phase that is less phosphorylation dependent.

Key words: Drosophila, bicoid, Par-1, Exn, Polarity, mRNA localisation


Related articles in Development:

Locating bicoid: step by step

Development 2004 131: e2303. [Full Text]  



This article has been cited by other articles:


Home page
 J. Cell Sci.Home page
J. Bayraktar, D. Zygmunt, and R. W. Carthew
Par-1 kinase establishes cell polarity and functions in Notch signaling in the Drosophila embryo
J. Cell Sci., February 15, 2006; 119(4): 711 - 721.
[Abstract] [Full Text] [PDF]


© The Company of Biologists Ltd 2004