The homo-oligomerisation of both Sas-6 and Ana2 is required for efficient centriole assembly in flies
Abstract
Sas-6 and Ana2/STIL proteins are required for centriole duplication and the homo-oligomerisation properties of Sas-6 help establish the nine-fold symmetry of the central cartwheel that initiates centriole assembly. Ana2/STIL proteins are poorly conserved, but they all contain a predicted Central Coiled-Coil Domain (CCCD). Here we show that the Drosophila Ana2 CCCD forms a tetramer, and we solve its structure to 0.8 Å, revealing that it adopts an unusual parallel-coil topology. We also solve the structure of the Drosophila Sas-6 N-terminal domain to 2.9 Å revealing that it forms higher-order oligomers through canonical interactions. Point mutations that perturb Sas-6 or Ana2 homo-oligomerisation in vitro strongly perturb centriole assembly in vivo. Thus, efficient centriole duplication in flies requires the homo-oligomerisation of both Sas-6 and Ana2, and the Ana2 CCCD tetramer structure provides important information on how these proteins might cooperate to form a cartwheel structure.
Article and author information
Author details
Reviewing Editor
- Anthony A Hyman, Max Planck Institute of Molecular Cell Biology and Genetics, Germany
Version history
- Received: February 27, 2015
- Accepted: May 22, 2015
- Accepted Manuscript published: May 23, 2015 (version 1)
- Version of Record published: June 18, 2015 (version 2)
Copyright
© 2015, Cottee 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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