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The structure of the dynactin complex and its interaction with dynein.

ABSTRACT: Dynactin is an essential cofactor for the microtubule motor cytoplasmic dynein-1. We report the structure of the 23-subunit dynactin complex by cryo-electron microscopy to 4.0 angstroms. Our reconstruction reveals how dynactin is built around a filament containing eight copies of the actin-related protein Arp1 and one of ?-actin. The filament is capped at each end by distinct protein complexes, and its length is defined by elongated peptides that emerge from the ?-helical shoulder domain. A further 8.2 angstrom structure of the complex between dynein, dynactin, and the motility-inducing cargo adaptor Bicaudal-D2 shows how the translational symmetry of the dynein tail matches that of the dynactin filament. The Bicaudal-D2 coiled coil runs between dynein and dynactin to stabilize the mutually dependent interactions between all three components.

SUBMITTER: Urnavicius L

PROVIDER: S-EPMC4413427 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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The structure of the dynactin complex and its interaction with dynein.

Urnavicius Linas L Zhang Kai K Diamant Aristides G AG Motz Carina C Schlager Max A MA Yu Minmin M Patel Nisha A NA Robinson Carol V CV Carter Andrew P AP

Science (New York, N.Y.) 20150212 6229

Dynactin is an essential cofactor for the microtubule motor cytoplasmic dynein-1. We report the structure of the 23-subunit dynactin complex by cryo-electron microscopy to 4.0 angstroms. Our reconstruction reveals how dynactin is built around a filament containing eight copies of the actin-related protein Arp1 and one of β-actin. The filament is capped at each end by distinct protein complexes, and its length is defined by elongated peptides that emerge from the α-helical shoulder domain. A furt ...[more]

PMID: 25814576

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