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

First published online 8 October 2008
doi: 10.1242/dev.027060

This Article Figures Only Full Text Full Text (PDF) Supplementary Material OA All Versions of this Article: dev.027060v1 135/22/3665    most recent 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 Tenlen, J. R. Articles by Priess, J. R. Search for Related Content PubMed PubMed Citation Articles by Tenlen, J. R. Articles by Priess, J. R. Social Bookmarking                         What's this?

MEX-5 asymmetry in one-cell C. elegans embryos requires PAR-4- and PAR-1-dependent phosphorylation

Jennifer R. Tenlen^1,2,*, Jeffrey N. Molk^2,, Nitobe London^2,3,, Barbara D. Page^2,3 and James R. Priess^1,2,3,4,

¹ Molecular and Cellular Biology Program, University of Washington, Seattle, WA 98195, USA.
² Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
³ Howard Hughes Medical Institute, Seattle, WA 98109, USA.
⁴ Department of Biology, University of Washington, Seattle, WA 98195, USA.

Author for correspondence (e-mail: jpriess{at}fhcrc.org)

Accepted 9 September 2008

Anteroposterior polarity in early C. elegans embryos is required for the specification of somatic and germline lineages, and is initiated by a sperm-induced reorganization of the cortical cytoskeleton and PAR polarity proteins. Through mechanisms that are not understood, the kinases PAR-1 and PAR-4, and other PAR proteins cause the cytoplasmic zinc finger protein MEX-5 to accumulate asymmetrically in the anterior half of the one-cell embryo. We show that MEX-5 asymmetry requires neither vectorial transport to the anterior, nor protein degradation in the posterior. MEX-5 has a restricted mobility before fertilization and in the anterior of one-cell embryos. However, MEX-5 mobility in the posterior increases as asymmetry develops, presumably allowing accumulation in the anterior. The MEX-5 zinc fingers and a small, C-terminal domain are essential for asymmetry; the zinc fingers restrict MEX-5 mobility, and the C-terminal domain is required for the increase in posterior mobility. We show that a crucial residue in the C-terminus, Ser 458, is phosphorylated in vivo. PAR-1 and PAR-4 kinase activities are required for the phosphorylation of S458, providing a link between PAR polarity proteins and the cytoplasmic asymmetry of MEX-5.

Key words: MEX-5, PAR-1, PAR-4, CCCH zinc finger proteins, C. elegans

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

Related articles in Development:

MEX-5 takes its PARtners for asymmetry

Development 2008 135: e2201. [Full Text]  

This article has been cited by other articles:

				M. Roh-Johnson and B. Goldstein In vivo roles for Arp2/3 in cortical actin organization during C. elegans gastrulation J. Cell Sci., November 1, 2009; 122(21): 3983 - 3993. [Abstract] [Full Text] [PDF]

				C. P. Brangwynne, C. R. Eckmann, D. S. Courson, A. Rybarska, C. Hoege, J. Gharakhani, F. Julicher, and A. A. Hyman Germline P Granules Are Liquid Droplets That Localize by Controlled Dissolution/Condensation Science, June 26, 2009; 324(5935): 1729 - 1732. [Abstract] [Full Text] [PDF]

				B. R. Daniels, E. M. Perkins, T. M. Dobrowsky, S. X. Sun, and D. Wirtz Asymmetric enrichment of PIE-1 in the Caenorhabditis elegans zygote mediated by binary counterdiffusion J. Cell Biol., February 23, 2009; 184(4): 473 - 479. [Abstract] [Full Text] [PDF]