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

First published online November 11, 2004
doi: 10.1242/10.1242/dev.01515

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 Related articles in Development 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 Riechmann, V. Articles by Ephrussi, A. Search for Related Content PubMed PubMed Citation Articles by Riechmann, V. Articles by Ephrussi, A. Social Bookmarking                         What's this?

Par-1 regulates bicoid mRNA localisation by phosphorylating Exuperantia

Veit Riechmann^* and Anne Ephrussi

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

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

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

Related articles in Development:

Locating bicoid: step by step

Development 2004 131: e2303. [Full Text]  

This article has been cited by other articles:

				R. Suyama, A. Jenny, S. Curado, W. Pellis-van Berkel, and A. Ephrussi The actin-binding protein Lasp promotes Oskar accumulation at the posterior pole of the Drosophila embryo Development, January 1, 2009; 136(1): 95 - 105. [Abstract] [Full Text] [PDF]

				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]