Aurora A depletion reveals centrosome-independent polarization mechanism in C. elegans
- Swiss Federal Institute of Technology, Switzerland
- University of Geneva, Switzerland
- Technische Universität Dresden, Germany
Abstract
How living systems break symmetry in an organized manner is a fundamental question in biology. In wild type Caenorhabditis elegans zygotes, symmetry breaking during anterior-posterior axis specification is guided by centrosomes, resulting in anterior-directed cortical flows and a single posterior PAR-2 domain. We uncover that C. elegans zygotes depleted of the Aurora A kinase AIR-1 or lacking centrosomes entirely usually establish two posterior PAR-2 domains, one at each pole. We demonstrate that AIR-1 prevents symmetry breaking early in the cell cycle, whereas centrosomal AIR-1 instructs polarity initiation thereafter. Using triangular microfabricated chambers, we establish that bipolarity of air-1(RNAi) embryos occurs effectively in a cell-shape and curvature-dependent manner. Furthermore, we develop an integrated physical description of symmetry breaking, wherein local PAR-2-dependent weakening of the actin cortex, together with mutual inhibition of anterior and posterior PAR proteins, provides a mechanism for spontaneous symmetry breaking without centrosomes.
Data availability
All data is available in the manuscript or the supplementary materials.
Article and author information
Author details
Funding
European Molecular Biology Organization (ALTF 81-2017)
- Kerstin Klinkert
European Molecular Biology Organization (ALTF 1426-2016)
- Marie Pierron
Fondation Bettencourt Schueller
- Nicolas Levernier
Swiss National Science Foundation (31003A_155942)
- Pierre Gönczy
Swiss National Science Foundation (205321_175996)
- Karsten Kruse
H2020 European Research Council (281903)
- Stephan W Grill
H2020 European Research Council (742712)
- Stephan W Grill
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Yukiko M Yamashita, University of Michigan, United States
Version history
- Received: December 19, 2018
- Accepted: February 24, 2019
- Accepted Manuscript published: February 25, 2019 (version 1)
- Accepted Manuscript updated: February 26, 2019 (version 2)
- Version of Record published: March 14, 2019 (version 3)
Copyright
© 2019, Klinkert et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Aurora A depletion reveals centrosome-independent polarization mechanism in C. elegans
eLife 8:e44552.
https://doi.org/10.7554/eLife.44552
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