8AT2

Structure of the augmin TIII subcomplex

Summary for 8AT2

• Entry DOI: 10.2210/pdb8at2/pdb
• EMDB information: 15631
• Descriptor: HAUS augmin-like complex subunit 1, HAUS augmin-like complex subunit 3, HAUS augmin like complex subunit 4 L homeolog, ... (4 entities in total)
• Functional Keywords: microtubule, branching, nucleation, cell cycle
• Biological source: Xenopus laevis (African clawed frog); More
• Total number of polymer chains: 4
• Total formula weight: 219410.65

Authors

Zupa, E.,Pfeffer, S. (deposition date: 2022-08-22, release date: 2022-09-28, Last modification date: 2025-07-09)

Primary citation

Zupa, E.,Wurtz, M.,Neuner, A.,Hoffmann, T.,Rettel, M.,Bohler, A.,Vermeulen, B.J.A.,Eustermann, S.,Schiebel, E.,Pfeffer, S.
The augmin complex architecture reveals structural insights into microtubule branching.
Nat Commun, 13:5635-5635, 2022

PubMed Abstract: In mitosis, the augmin complex binds to spindle microtubules to recruit the γ-tubulin ring complex (γ-TuRC), the principal microtubule nucleator, for the formation of branched microtubules. Our understanding of augmin-mediated microtubule branching is hampered by the lack of structural information on the augmin complex. Here, we elucidate the molecular architecture and conformational plasticity of the augmin complex using an integrative structural biology approach. The elongated structure of the augmin complex is characterised by extensive coiled-coil segments and comprises two structural elements with distinct but complementary functions in γ-TuRC and microtubule binding, linked by a flexible hinge. The augmin complex is recruited to microtubules via a composite microtubule binding site comprising a positively charged unordered extension and two calponin homology domains. Our study provides the structural basis for augmin function in branched microtubule formation, decisively fostering our understanding of spindle formation in mitosis.

PubMed: 36163468
DOI: 10.1038/s41467-022-33228-6

Experimental method

ELECTRON MICROSCOPY (7.7 Å)