1. Structural Biology and Molecular Biophysics
  2. Cell Biology
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Mapping translation 'hot-spots' in live cells by tracking single molecules of mRNA and ribosomes

  1. Zachary B Katz
  2. Brian p English
  3. Timothée Lionnet
  4. Young J Yoon
  5. Nilah Monnier
  6. Ben Ovryn
  7. Mark Bathe
  8. Robert H Singer  Is a corresponding author
  1. Albert Einstein College of Medicine, United States
  2. Janelia Research Campus, Howard Hughes Medical Institute, United States
  3. Stanford University School of Medicine, United States
  4. Massachusetts Institute of Technology, United States
Research Article
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Cite this article as: eLife 2016;5:e10415 doi: 10.7554/eLife.10415

Abstract

Messenger RNA localization is important for cell motility by local protein translation. However, while single mRNAs can be imaged and their movements tracked in single cells, it has not yet been possible to determine whether these mRNAs are actively translating. Therefore, we imaged single β-actin mRNAs tagged with MS2 stem loops colocalizing with labeled ribosomes to determine when polysomes formed. A dataset of tracking information consisting of thousands of trajectories per cell demonstrated that mRNAs co-moving with ribosomes have significantly different diffusion properties from non-translating mRNAs that were exposed to translation inhibitors. This data indicates that ribosome load changes mRNA movement and therefore highly translating mRNAs move slower. Importantly, β-actin mRNA near focal adhesions exhibited sub-diffusive corralled movement characteristic of increased translation. This method can identify where ribosomes become engaged for local protein production and how spatial regulation of mRNA-protein interactions mediates cell directionality.

Article and author information

Author details

  1. Zachary B Katz

    Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, New York, United States
    Competing interests
    No competing interests declared.
  2. Brian p English

    Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, New York, United States
    Competing interests
    No competing interests declared.
  3. Timothée Lionnet

    Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, United States
    Competing interests
    No competing interests declared.
  4. Young J Yoon

    Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, New York, United States
    Competing interests
    No competing interests declared.
  5. Nilah Monnier

    Department of Genetics, Stanford University School of Medicine, Stanford, United States
    Competing interests
    No competing interests declared.
  6. Ben Ovryn

    Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, New York, United States
    Competing interests
    No competing interests declared.
  7. Mark Bathe

    Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, United States
    Competing interests
    No competing interests declared.
  8. Robert H Singer

    Department of Anatomy and Structural Biology, Albert Einstein College of Medicine, New York, United States
    For correspondence
    robert.singer@einstein.yu.edu
    Competing interests
    Robert H Singer, Reviewing editor, eLife.

Reviewing Editor

  1. Nahum Sonenberg, McGill University, Canada

Publication history

  1. Received: July 28, 2015
  2. Accepted: December 29, 2015
  3. Accepted Manuscript published: January 13, 2016 (version 1)
  4. Version of Record published: February 12, 2016 (version 2)

Copyright

© 2016, Katz 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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