RNA-directed activation of cytoplasmic dynein-1 in reconstituted transport RNPs

Abstract

Polarised mRNA transport is a prevalent mechanism for spatial control of protein synthesis. However, the composition of transported ribonucleoprotein particles (RNPs) and the regulation of their movement are poorly understood. We have reconstituted microtubule minus end-directed transport of mRNAs using purified components. A Bicaudal-D (BicD) adaptor protein and the RNA-binding protein Egalitarian (Egl) are sufficient for long-distance mRNA transport by the dynein motor and its accessory complex dynactin, thus defining a minimal transport-competent RNP. Unexpectedly, the RNA is required for robust activation of dynein motility. We show that a cis-acting RNA localisation signal promotes the interaction of Egl with BicD, which licenses the latter protein to recruit dynein and dynactin. Our data support a model for BicD activation based on RNA-induced occupancy of two Egl-binding sites on the BicD dimer. Scaffolding of adaptor protein assemblies by cargoes is an attractive mechanism for regulating intracellular transport.

Data availability

All data generated or analysed during this study are included in the manuscript and supporting files.

Article and author information

Author details

  1. Mark A McClintock

    Division of Cell Biology, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    No competing interests declared.
  2. Carly I Dix

    Division of Cell Biology, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    Carly I Dix, is currently affiliated with AstraZeneca Discovery Sciences. The research was conducted when the author was still at the MRC Laboratory of Molecular Biology. The author has no other financial interests to declare.
  3. Christopher M Johnson

    Protein and Nucleic Acid Chemistry, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    No competing interests declared.
  4. Stephen H McLaughlin

    Protein and Nucleic Acid Chemistry, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9135-6253
  5. Rory J Maizels

    Division of Cell Biology, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    No competing interests declared.
  6. Ha Thi Hoang

    Division of Cell Biology, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    Competing interests
    Ha Thi Hoang, is currently affiliated with MicroInventa Limited. The research was conducted when the author was still at the MRC Laboratory of Molecular Biology. The author has no other financial interests to declare.
  7. Simon L Bullock

    Division of Cell Biology, MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
    For correspondence
    sbullock@mrc-lmb.cam.ac.uk
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9491-4548

Funding

Medical Research Council (MC_U105178790)

  • Mark A McClintock
  • Carly I Dix
  • Christopher M Johnson
  • Stephen H McLaughlin
  • Rory J Maizels
  • Ha Thi Hoang
  • Simon L Bullock

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

Reviewing Editor

  1. Andrea Musacchio, Max Planck Institute of Molecular Physiology, Germany

Publication history

  1. Received: March 1, 2018
  2. Accepted: June 19, 2018
  3. Accepted Manuscript published: June 26, 2018 (version 1)
  4. Version of Record published: July 23, 2018 (version 2)

Copyright

© 2018, McClintock 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. Mark A McClintock
  2. Carly I Dix
  3. Christopher M Johnson
  4. Stephen H McLaughlin
  5. Rory J Maizels
  6. Ha Thi Hoang
  7. Simon L Bullock
(2018)
RNA-directed activation of cytoplasmic dynein-1 in reconstituted transport RNPs
eLife 7:e36312.
https://doi.org/10.7554/eLife.36312

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