8QRY

Crystal structure of the yeast spindle body component Spc98

Summary for 8QRY

• Entry DOI: 10.2210/pdb8qry/pdb
• Descriptor: Spindle pole body component (2 entities in total)
• Functional Keywords: yeast cell division, yeast spindle pole body, cell cycle
• Biological source: Saccharomyces cerevisiae (baker's yeast)
• Total number of polymer chains: 1
• Total formula weight: 10826.42

Authors

Bellini, D.,Yatskevich, S.,Barford, D. (deposition date: 2023-10-09, release date: 2024-04-03, Last modification date: 2024-10-16)

Primary citation

Dendooven, T.,Yatskevich, S.,Burt, A.,Chen, Z.A.,Bellini, D.,Rappsilber, J.,Kilmartin, J.V.,Barford, D.
Structure of the native gamma-tubulin ring complex capping spindle microtubules.
Nat.Struct.Mol.Biol., 31:1134-1144, 2024

PubMed Abstract: Microtubule (MT) filaments, composed of α/β-tubulin dimers, are fundamental to cellular architecture, function and organismal development. They are nucleated from MT organizing centers by the evolutionarily conserved γ-tubulin ring complex (γTuRC). However, the molecular mechanism of nucleation remains elusive. Here we used cryo-electron tomography to determine the structure of the native γTuRC capping the minus end of a MT in the context of enriched budding yeast spindles. In our structure, γTuRC presents a ring of γ-tubulin subunits to seed nucleation of exclusively 13-protofilament MTs, adopting an active closed conformation to function as a perfect geometric template for MT nucleation. Our cryo-electron tomography reconstruction revealed that a coiled-coil protein staples the first row of α/β-tubulin of the MT to alternating positions along the γ-tubulin ring of γTuRC. This positioning of α/β-tubulin onto γTuRC suggests a role for the coiled-coil protein in augmenting γTuRC-mediated MT nucleation. Based on our results, we describe a molecular model for budding yeast γTuRC activation and MT nucleation.

PubMed: 38609662
DOI: 10.1038/s41594-024-01281-y

Experimental method

X-RAY DIFFRACTION (1.87 Å)