Centriolar SAS-7 acts upstream of SPD-2 to regulate centriole assembly and pericentriolar material formation
Abstract
The centriole/basal body is a eukaryotic organelle that plays essential roles in cell division and signaling. Among five known core centriole proteins, SPD-2/Cep192 is the first recruited to the site of daughter centriole formation and regulates the centriolar localization of the other components in C. elegans and in humans. However, the molecular basis for SPD-2 centriolar localization remains unknown. Here we describe a new centriole component, the coiled-coil protein SAS-7, as a regulator of centriole duplication, assembly and elongation. We also show that SAS-7 binds SPD-2 and regulates SPD-2 centriolar recruitment, while SAS-7 centriolar localization is SPD-2-independent. Furthermore, pericentriolar material (PCM) formation is abnormal in sas-7 mutants, and the PCM-dependent induction of cell polarity that defines the anterior-posterior body axis frequently fails. We conclude that SAS-7 functions at the earliest step in centriole duplication yet identified and plays important roles in the orchestration of centriole and PCM assembly.
Article and author information
Author details
Funding
Human Frontier Science Program
- Kenji Sugioka
Journal of Cell Science Traveling Fellowship
- Kenji Sugioka
National Institute of General Medical Sciences
- Kenji Sugioka
- Danielle R Hamill
- Joshua B Lowry
- Marie E McNeely
- Molly Enrick
- Alyssa C Richter
- Lauren E Kiebler
- James R Priess
- Bruce Bowerman
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2017, Sugioka 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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