1. Structural Biology and Molecular Biophysics

Cryo-EM of dynein microtubule-binding domains shows how an axonemal dynein distorts the microtubule

  1. Samuel E Lacey
  2. Shaoda He
  3. Sjors HW Scheres
  4. Andrew P Carter  Is a corresponding author
  1. MRC Laboratory of Molecular Biology, United Kingdom
https://doi.org/10.7554/eLife.47145
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  1. Samuel E Lacey
  2. Shaoda He
  3. Sjors HW Scheres
  4. Andrew P Carter
(2019)
Cryo-EM of dynein microtubule-binding domains shows how an axonemal dynein distorts the microtubule
eLife 8:e47145.
https://doi.org/10.7554/eLife.47145
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Abstract

Dyneins are motor proteins responsible for transport in the cytoplasm and the beating of axonemes in cilia and flagella. They bind and release microtubules via a compact microtubule-binding domain (MTBD) at the end of a coiled-coil stalk. We address how cytoplasmic and axonemal dynein MTBDs bind microtubules at near atomic resolution. We decorated microtubules with MTBDs of cytoplasmic dynein-1 and axonemal dynein DNAH7 and determined their cryo-EM structures using helical Relion. The majority of the MTBD is rigid upon binding, with the transition to the high affinity state controlled by the movement of a single helix at the MTBD interface. DNAH7 contains an 18-residue insertion, found in many axonemal dyneins, that contacts the adjacent protofilament. Unexpectedly we observe that DNAH7, but not dynein-1, induces large distortions in the microtubule cross-sectional curvature. This raises the possibility that dynein coordination in axonemes is mediated via conformational changes in the microtubule.

Data availability

CryoEM maps have been deposited to the EMDB and are instructed to be released on publication under codes 10060 and 10061PDB models have been deposited to the PDB and are instructed to be released on publication under codes 6RZA and 6RZB

The following data sets were generated
The following previously published data sets were used

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Author details

  1. Samuel E Lacey

    MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    No competing interests declared.

  2. Shaoda He

    MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    No competing interests declared.

  3. Sjors HW Scheres

    MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    Sjors HW Scheres, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0462-6540

  4. Andrew P Carter

    MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    For correspondence
    cartera@mrc-lmb.cam.ac.uk
    Competing interests
    Andrew P Carter, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7292-5430

Funding

Wellcome (WT210711)

  • Andrew P Carter

Medical Research Council (MC_UP_A025_1011)

  • Andrew P Carter

Medical Research Council (MC_UP_A025_1011)

  • Sjors HW Scheres

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Samara L Reck-Peterson, University of California, San Diego, United States

Publication history

  1. Received: March 26, 2019
  2. Accepted: July 1, 2019
  3. Accepted Manuscript published: July 2, 2019 (version 1)
  4. Version of Record published: July 15, 2019 (version 2)

Copyright

© 2019, Lacey et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Samuel E Lacey
  2. Shaoda He
  3. Sjors HW Scheres
  4. Andrew P Carter
(2019)
Cryo-EM of dynein microtubule-binding domains shows how an axonemal dynein distorts the microtubule
eLife 8:e47145.
https://doi.org/10.7554/eLife.47145

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