Self-assembly of pericentriolar material in interphase cells lacking centrioles
Abstract
The major microtubule-organizing center (MTOC) in animal cells, the centrosome, comprises a pair of centrioles surrounded by pericentriolar material (PCM), which nucleates and anchors microtubules. Centrosome assembly depends on PCM binding to centrioles, PCM self-association and dynein-mediated PCM transport, but the self-assembly properties of PCM components in interphase cells are poorly understood. Here, we used experiments and modeling to study centriole-independent features of interphase PCM assembly. We showed that when centrioles are lost due to PLK4 depletion or inhibition, dynein-based transport and self-clustering of PCM proteins are sufficient to form a single compact MTOC, which generates a dense radial microtubule array. Interphase self-assembly of PCM components depends on γ-tubulin, pericentrin, CDK5RAP2 and ninein, but not NEDD1, CEP152 or CEP192. Formation of a compact acentriolar MTOC is inhibited by AKAP450-dependent PCM recruitment to the Golgi or by randomly organized CAMSAP2-stabilized microtubules, which keep PCM mobile and prevent its coalescence. Linking of CAMSAP2 to a minus-end-directed motor leads to the formation of an MTOC, but MTOC compaction requires cooperation with pericentrin-containing self-clustering PCM. Our data reveal that interphase PCM contains a set of components that can self-assemble into a compact structure and organize microtubules, but PCM self-organization is sensitive to motor- and microtubule-based rearrangement.
Data availability
The images of uncropped Western blots assembled into figures, with the relevant bands clearly labeled, are included directly in the article file to facilitate peer review (the last two pages of the manuscript file).The configuration file for Cytosim, the software used for simulations, is included as Supplemental File 1.All numerical data and all raw Western blot data are included as Source Data files.
Article and author information
Author details
Funding
China Scholarship Council (Scholraship)
- Fangrui Chen
China Scholarship Council (Scholarship)
- Jingchao Wu
China Scholarship Council (Scholaship)
- Chao Yang
Nederlandse Organisatie voor Wetenschappelijk Onderzoek (Spinoza prize)
- Anna Akhmanova
European Research Council (Consolidator Grant 819219)
- Lukas C Kapitein
cEindhoven-Wageningen-Utrecht Alliance (Support for Center for Living Technologies)
- Lukas C Kapitein
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2022, Chen 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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