The cryo-EM structure of a γ-TuSC elucidates architecture and regulation of minimal microtubule nucleation systems
The nucleation of microtubules from αβ-tubulin subunits is mediated by γ-tubulin complexes, which vary in composition across organisms. Aiming to understand how de novo microtubule formation is achieved and regulated by a minimal microtubule nucleation system, we here determined the cryo-electron mi...
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| Main Authors: | , , , , , , , |
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| Format: | Article (Journal) |
| Language: | English |
| Published: |
11 November 2020
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| In: |
Nature Communications
Year: 2020, Volume: 11 |
| ISSN: | 2041-1723 |
| DOI: | 10.1038/s41467-020-19456-8 |
| Online Access: | Verlag, kostenfrei, Volltext: https://doi.org/10.1038/s41467-020-19456-8 Verlag, kostenfrei, Volltext: https://www.nature.com/articles/s41467-020-19456-8 
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| Author Notes: | Erik Zupa, Anjun Zheng, Annett Neuner, Martin Würtz, Peng Liu, Anna Böhler, Elmar Schiebel & Stefan Pfeffer |
| Summary: | The nucleation of microtubules from αβ-tubulin subunits is mediated by γ-tubulin complexes, which vary in composition across organisms. Aiming to understand how de novo microtubule formation is achieved and regulated by a minimal microtubule nucleation system, we here determined the cryo-electron microscopy structure of the heterotetrameric γ-tubulin small complex (γ-TuSC) from C. albicans at near-atomic resolution. Compared to the vertebrate γ-tubulin ring complex (γ-TuRC), we observed a vastly remodeled interface between the SPC/GCP-γ-tubulin spokes, which stabilizes the complex and defines the γ-tubulin arrangement. The relative positioning of γ-tubulin subunits indicates that a conformational rearrangement of the complex is required for microtubule nucleation activity, which follows opposing directionality as predicted for the vertebrate γ-TuRC. Collectively, our data suggest that the assembly and regulation mechanisms of γ-tubulin complexes fundamentally differ between the microtubule nucleation systems in lower and higher eukaryotes. |
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| Item Description: | Gesehen am 15.01.2021 |
| Physical Description: | Online Resource |
| ISSN: | 2041-1723 |
| DOI: | 10.1038/s41467-020-19456-8 |