Cryo-EM of dynein microtubule-binding domains shows how an axonemal dynein distorts the microtubule
- MRC Laboratory of Molecular Biology, United Kingdom
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
Article and author information
Author details
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.
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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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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