9H9P

Spokes 12 and 13 of the human gamma-tubulin ring complex in complex with CDK5RAP2 and docked MZT2/GCP2-NHD module

Summary for 9H9P

• Entry DOI: 10.2210/pdb9h9p/pdb
• Related: 9H9Q 9H9R
• EMDB information: 21985 51971 51972
• Descriptor: CDK5 regulatory subunit-associated protein 2, Gamma-tubulin complex component 6, Isoform 3 of Gamma-tubulin complex component 2, ... (6 entities in total)
• Functional Keywords: cytoskeleton, microtubule, microtubule nucleation, complex, template, cap, gamma-tubulin, gamma-tubulin ring complex, cdk5rap2, homo, sapiens, gcp6, gcp2, gamma-tubulin complex protein, mzt2, mozart, mozart2, module, cm1, cm1 motif, cep215, cell cycle
• Biological source: Homo sapiens (human); More
• Total number of polymer chains: 7
• Total formula weight: 856972.70

Authors

Vermeulen, B.J.A.,Pfeffer, S. (deposition date: 2024-10-31, release date: 2025-01-15)

Primary citation

Zheng, A.,Vermeulen, B.J.A.,Wurtz, M.,Neuner, A.,Lubbehusen, N.,Mayer, M.P.,Schiebel, E.,Pfeffer, S.
Structural insights into the interplay between microtubule polymerases, gamma-tubulin complexes and their receptors.
Nat Commun, 16:402-402, 2025

PubMed Abstract: The γ-tubulin ring complex (γ-TuRC) is a structural template for controlled nucleation of microtubules from α/β-tubulin heterodimers. At the cytoplasmic side of the yeast spindle pole body, the CM1-containing receptor protein Spc72 promotes γ-TuRC assembly from seven γ-tubulin small complexes (γ-TuSCs) and recruits the microtubule polymerase Stu2, yet their molecular interplay remains unclear. Here, we determine the cryo-EM structure of the Candida albicans cytoplasmic nucleation unit at 3.6 Å resolution, revealing how the γ-TuRC is assembled and conformationally primed for microtubule nucleation by the dimerised Spc72 CM1 motif. Two coiled-coil regions of Spc72 interact with the conserved C-terminal α-helix of Stu2 and thereby position the α/β-tubulin-binding TOG domains of Stu2 in the vicinity of the microtubule assembly site. Collectively, we reveal the function of CM1 motifs in γ-TuSC oligomerisation and the recruitment of microtubule polymerases to the γ-TuRC.

PubMed: 39757296
DOI: 10.1038/s41467-024-55778-7

Experimental method

ELECTRON MICROSCOPY (4.5 Å)