Structural mechanisms for centrosomal recruitment and organization of the microtubule nucleator γ-TuRC
The γ-tubulin ring complex (γ-TuRC) acts as a structural template for microtubule formation at centrosomes, associating with two main compartments: the pericentriolar material and the centriole lumen. In the pericentriolar material, the γ-TuRC is involved in microtubule organization, while the funct...
Saved in:
| Main Authors: | , , , , , , , , , , , , |
|---|---|
| Format: | Article (Journal) |
| Language: | English |
| Published: |
12 March 2025
|
| In: |
Nature Communications
Year: 2025, Volume: 16, Pages: 1-23 |
| ISSN: | 2041-1723 |
| DOI: | 10.1038/s41467-025-57729-2 |
| Online Access: | Verlag, kostenfrei, Volltext: https://doi.org/10.1038/s41467-025-57729-2 Verlag, kostenfrei, Volltext: https://www.nature.com/articles/s41467-025-57729-2 
|
| Author Notes: | Qi Gao, Florian W. Hofer, Sebastian Filbeck, Bram J. A. Vermeulen, Martin Würtz, Annett Neuner, Charlotte Kaplan, Maja Zezlina, Cornelia Sala, Hyesu Shin, Oliver J. Gruss, Elmar Schiebel & Stefan Pfeffer |
| Summary: | The γ-tubulin ring complex (γ-TuRC) acts as a structural template for microtubule formation at centrosomes, associating with two main compartments: the pericentriolar material and the centriole lumen. In the pericentriolar material, the γ-TuRC is involved in microtubule organization, while the function of the centriole lumenal pool remains unclear. The conformational landscape of the γ-TuRC, which is crucial for its activity, and its centrosomal anchoring mechanisms, which determine γ-TuRC activity and turnover, are not understood. Using cryo-electron tomography, we analyze γ-TuRCs in human cells and purified centrosomes. Pericentriolar γ-TuRCs simultaneously associate with the essential adapter NEDD1 and the microcephaly protein CDK5RAP2. NEDD1 forms a tetrameric structure at the γ-TuRC base through interactions with four GCP3/MZT1 modules and GCP5/6-specific extensions, while multiple copies of CDK5RAP2 engage the γ-TuRC in two distinct binding patterns to promote γ-TuRC closure and activation. In the centriole lumen, the microtubule branching factor Augmin tethers a condensed cluster of γ-TuRCs to the centriole wall with defined directional orientation. Centriole-lumenal γ-TuRC-Augmin is protected from degradation during interphase and released in mitosis to aid chromosome alignment. This study provides a unique view on γ-TuRC structure and molecular organization at centrosomes and identifies an important cellular function of centriole-lumenal γ-TuRCs. |
|---|---|
| Item Description: | Gesehen am 12.08.2025 |
| Physical Description: | Online Resource |
| ISSN: | 2041-1723 |
| DOI: | 10.1038/s41467-025-57729-2 |