Distinct stages of the translation elongation cycle revealed by sequencing ribosome-protected mRNA fragments

  1. Liana F Lareau  Is a corresponding author
  2. Dustin H Hite
  3. Gregory J Hogan
  4. Patrick O Brown
  1. California Institute for Quantitative Biosciences, University of California, Berkeley, United States
  2. Howard Hughes Medical Institute, Stanford University School of Medicine, United States

Abstract

During translation elongation, the ribosome ratchets along its mRNA template, incorporating each new amino acid and translocating from one codon to the next. The elongation cycle requires dramatic structural rearrangements of the ribosome. We show here that deep sequencing of ribosome-protected mRNA fragments reveals not only the position of each ribosome but also, unexpectedly, its particular stage of the elongation cycle. Sequencing reveals two distinct populations of ribosome footprints, 28-30 nucleotides and 20-22 nucleotides long, representing translating ribosomes in distinct states, differentially stabilized by specific elongation inhibitors. We find that the balance of small and large footprints varies by codon and is correlated with translation speed. The ability to visualize conformational changes in the ribosome during elongation, at single-codon resolution, provides a new way to study the detailed kinetics of translation and a new probe with which to identify the factors that affect each step in the elongation cycle.

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Author details

  1. Liana F Lareau

    California Institute for Quantitative Biosciences, University of California, Berkeley, Berkeley, United States
    For correspondence
    lareau@berkeley.edu
    Competing interests
    The authors declare that no competing interests exist.
  2. Dustin H Hite

    Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Gregory J Hogan

    Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Patrick O Brown

    Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, United States
    Competing interests
    The authors declare that no competing interests exist.

Copyright

© 2014, Lareau 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. Liana F Lareau
  2. Dustin H Hite
  3. Gregory J Hogan
  4. Patrick O Brown
(2014)
Distinct stages of the translation elongation cycle revealed by sequencing ribosome-protected mRNA fragments
eLife 3:e01257.
https://doi.org/10.7554/eLife.01257

Share this article

https://doi.org/10.7554/eLife.01257

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