9EOJ

Vertebrate microtubule-capping gamma-tubulin ring complex

これはPDB形式変換不可エントリーです。

9EOJ の概要

• エントリーDOI: 10.2210/pdb9eoj/pdb
• EMDBエントリー: 19861
• 分子名称: Mitotic-spindle organizing protein 1, Gamma-tubulin complex component 3 homolog, Gamma-tubulin complex component, ... (7 entities in total)
• 機能のキーワード: cytoskeleton, microtubule, microtubule nucleation, complex, template, cap, gamma-tubulin, gamma-tubulin ring complex, cell cycle
• 由来する生物種: Xenopus laevis (African clawed frog); 詳細
• タンパク質・核酸の鎖数: 30
• 化学式量合計: 2231854.79

構造登録者

Vermeulen, B.J.A.,Pfeffer, S. (登録日: 2024-03-15, 公開日: 2024-04-17, 最終更新日: 2024-11-13)

主引用文献

Vermeulen, B.J.,Bohler, A.,Gao, Q.,Neuner, A.,Zupa, E.,Chu, Z.,Wurtz, M.,Jakle, U.,Gruss, O.J.,Pfeffer, S.,Schiebel, E.
gamma-TuRC asymmetry induces local protofilament mismatch at the RanGTP-stimulated microtubule minus end.
Embo J., 43:2062-2085, 2024

PubMed Abstract: The γ-tubulin ring complex (γ-TuRC) is a structural template for de novo microtubule assembly from α/β-tubulin units. The isolated vertebrate γ-TuRC assumes an asymmetric, open structure deviating from microtubule geometry, suggesting that γ-TuRC closure may underlie regulation of microtubule nucleation. Here, we isolate native γ-TuRC-capped microtubules from Xenopus laevis egg extract nucleated through the RanGTP-induced pathway for spindle assembly and determine their cryo-EM structure. Intriguingly, the microtubule minus end-bound γ-TuRC is only partially closed and consequently, the emanating microtubule is locally misaligned with the γ-TuRC and asymmetric. In the partially closed conformation of the γ-TuRC, the actin-containing lumenal bridge is locally destabilised, suggesting lumenal bridge modulation in microtubule nucleation. The microtubule-binding protein CAMSAP2 specifically binds the minus end of γ-TuRC-capped microtubules, indicating that the asymmetric minus end structure may underlie recruitment of microtubule-modulating factors for γ-TuRC release. Collectively, we reveal a surprisingly asymmetric microtubule minus end protofilament organisation diverging from the regular microtubule structure, with direct implications for the kinetics and regulation of nucleation and subsequent modulation of microtubules during spindle assembly.

PubMed: 38600243
DOI: 10.1038/s44318-024-00087-4

実験手法

ELECTRON MICROSCOPY (17 Å)