Insights into centriole geometry revealed by cryoTomography of doublet and triplet centrioles
- University of California, San Francisco, United States
Abstract
Centrioles are cylindrical assemblies comprised of 9 singlet, doublet, or triplet microtubules, essential for the formation of motile and sensory cilia. While the structure of the cilium is being defined at increasing resolution, centriolar structure remains poorly understood. Here, we used electron cryo-tomography to determine the structure of mammalian (triplet) and Drosophila (doublet) centrioles. Mammalian centrioles have two distinct domains: a 200 nm proximal core region connected by A-C linkers, and a distal domain where the C-tubule is incomplete and a pair of novel linkages stabilize the assembly producing a geometry more closely resembling the ciliary axoneme. Drosophila centrioles resemble the mammalian core, but with their doublet microtubules linked through the A tubules. The commonality of core-region length, and the abrupt transition in mammalian centrioles, suggests a conserved length-setting mechanism. The unexpected linker diversity suggests how unique centriolar architectures arise in different tissues and organisms.
Data availability
Average maps have been submitted to the Electron Microscopy Database (EMDB)
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Author details
Funding
Howard Hughes Medical Institute
- Ronald D Vale
- David A Agard
National Institute of General Medical Sciences (GM031627)
- David A Agard
National Institute of General Medical Sciences (GM118099)
- David A Agard
National Institute of General Medical Sciences (GM118106)
- Ronald D Vale
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2018, Greenan 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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Insights into centriole geometry revealed by cryoTomography of doublet and triplet centrioles
eLife 7:e36851.
https://doi.org/10.7554/eLife.36851
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