Ciliary transcription factors and miRNAs precisely regulate Cp110 levels required for ciliary adhesions and ciliogenesis
Abstract
Upon cell cycle exit, centriole-to-basal body transition facilitates cilia formation. The centriolar protein Cp110 is a regulator of this process and cilia inhibitor, but its positive roles in ciliogenesis remain poorly understood. Using Xenopus we show that Cp110 inhibits cilia formation at high levels, while optimal levels promote ciliogenesis. Cp110 localizes to cilia-forming basal bodies and rootlets, and is required for ciliary adhesion complexes that facilitate Actin interactions. The opposing roles of Cp110 in ciliation are generated in part by coiled-coil domains that mediate preferential binding to centrioles over rootlets. Because of its dual role in ciliogenesis, Cp110 levels must be precisely controlled. In multiciliated cells, this is achieved by both transcriptional and post-transcriptional regulation through ciliary transcription factors and microRNAs, which activate and repress cp110 to produce optimal Cp110 levels during ciliogenesis. Our data provide novel insights into how Cp110 and its regulation contribute to development and cell function.
Data availability
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RNAseq profiling of multiciliated cellsPublicly available at the NCBI Gene Expression Omnibus (accession no: GSE76342).
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Multicilin drives centriole biogenesis via E2f proteinsPublicly available at the NCBI Gene Expression Omnibus (accession no: GSE59309).
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Coordinated genomic control of ciliogenesis and cell movement by RFX2Publicly available at the NCBI Gene Expression Omnibus (accession no: GSE50593).
Article and author information
Author details
Funding
Deutsche Forschungsgemeinschaft (Wa 3365/1-1)
- Peter Walentek
National Heart, Lung, and Blood Institute (K99HL127275)
- Peter Walentek
National Institute of General Medical Sciences (GM42341)
- Richard M Harland
National Institute of General Medical Sciences (GM076507)
- Christopher Kintner
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This work was done with approval of University of California, Berkeley's Animal Care and Use Committee. University of California, Berkeley's assurance number is A3084-01, and is on file at the National Institutes of Health Office of Laboratory Animal Welfare.
Copyright
© 2016, Walentek 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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Further reading
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