Projects per year
Abstract
The γ-tubulin ring complex (γTuRC) is the major microtubule nucleator in cells. The mechanism of its regulation is not understood. We purified human γTuRC and measured its nucleation properties in a total internal reflection fluorescence (TIRF) microscopy-based real-time nucleation assay. We find that γTuRC stably caps the minus ends of microtubules that it nucleates stochastically. Nucleation is inefficient compared with microtubule elongation. The 4 Å resolution cryoelectron microscopy (cryo-EM) structure of γTuRC, combined with crosslinking mass spectrometry analysis, reveals an asymmetric conformation with only part of the complex in a “closed” conformation matching the microtubule geometry. Actin in the core of the complex, and MZT2 at the outer perimeter of the closed part of γTuRC appear to stabilize the closed conformation. The opposite side of γTuRC is in an “open,” nucleation-incompetent conformation, leading to a structural asymmetry explaining the low nucleation efficiency of purified human γTuRC. Our data suggest possible regulatory mechanisms for microtubule nucleation by γTuRC closure.
Original language | English |
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Pages (from-to) | 603-617.e8 |
Journal | Developmental Cell |
Volume | 53 |
Issue number | 5 |
Early online date | 19 May 2020 |
DOIs | |
Publication status | E-pub ahead of print - 19 May 2020 |
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Dive into the research topics of 'Microtubule nucleation properties of single human γTuRCs explained by their Cryo-EM structure'. Together they form a unique fingerprint.Projects
- 4 Finished
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`Core Funding for the Wellcome Trust Centre for Cell Biology¿, Research Enrichment, Public Engagement
Tollervey, D. (Principal Investigator)
1/12/18 → 1/06/22
Project: Research
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Wellcome Centre for Cell Biology
Tollervey, D. (Principal Investigator)
1/12/16 → 1/12/21
Project: Research
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Proteomics at the Wellcome Trust Centre for Cell Biology (WTCCB) and School of Biological Sciences (SBS), Edinburgh
Rappsilber, J. (Principal Investigator)
1/10/15 → 30/09/20
Project: Research