EMD-7000
Subtomogram average of microtubule-bound dynein-dynactin-BICD2N complex
EMD-7000
Subtomogram averaging38.0 Å
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Map released: 20/09/2017
Last modified: 21/03/2018
Sample Organism:
Mus musculus
Sample: microtubule-bound dynein-dynactin-BICD2N complex
Raw data: EMPIAR-10520
Deposition Authors: Grotjahn DA, Chowdhury S, Xu Y, McKenney RJ, Schroer TA, Lander GC
Sample: microtubule-bound dynein-dynactin-BICD2N complex
Raw data: EMPIAR-10520
Deposition Authors: Grotjahn DA, Chowdhury S, Xu Y, McKenney RJ, Schroer TA, Lander GC
Cryo-electron tomography reveals that dynactin recruits a team of dyneins for processive motility.
Grotjahn DA,
Chowdhury S
,
Xu Y,
McKenney RJ,
Schroer TA,
Lander GC
(2018) Nat. Struct. Mol. Biol. , 25 , 203 - 207
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(2018) Nat. Struct. Mol. Biol. , 25 , 203 - 207
Abstract:
Cytoplasmic dynein is a protein complex that transports molecular cargo along microtubules (MTs), playing a key role in the intracellular trafficking network. Vertebrate dynein's movement becomes strikingly enhanced upon interacting with dynactin and a cargo adaptor such as BicaudalD2. However, the mechanisms responsible for increased transport activity are not well understood, largely owing to limited structural information. We used cryo-electron tomography (cryo-ET) to visualize the 3D structure of the MT-bound dynein-dynactin complex from Mus musculus and show that the dynactin-cargo adaptor complex binds two dimeric dyneins. This configuration imposes spatial and conformational constraints on both dynein dimers, positioning the four motor domains in proximity to one another and oriented toward the MT minus end. We propose that grouping multiple dyneins onto a single dynactin scaffold promotes collective force production, increased processivity, and unidirectional movement, suggesting mechanistic parallels to axonemal dynein. These findings provide structural insights into a previously unknown mechanism for dynein regulation.
Cytoplasmic dynein is a protein complex that transports molecular cargo along microtubules (MTs), playing a key role in the intracellular trafficking network. Vertebrate dynein's movement becomes strikingly enhanced upon interacting with dynactin and a cargo adaptor such as BicaudalD2. However, the mechanisms responsible for increased transport activity are not well understood, largely owing to limited structural information. We used cryo-electron tomography (cryo-ET) to visualize the 3D structure of the MT-bound dynein-dynactin complex from Mus musculus and show that the dynactin-cargo adaptor complex binds two dimeric dyneins. This configuration imposes spatial and conformational constraints on both dynein dimers, positioning the four motor domains in proximity to one another and oriented toward the MT minus end. We propose that grouping multiple dyneins onto a single dynactin scaffold promotes collective force production, increased processivity, and unidirectional movement, suggesting mechanistic parallels to axonemal dynein. These findings provide structural insights into a previously unknown mechanism for dynein regulation.