1. Biochemistry and Chemical Biology
  2. Genetics and Genomics
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Extensive translation of small ORFs revealed by Poly-Ribo-Seq

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Cite this article as: eLife 2014;3:e03528 doi: 10.7554/eLife.03528

Abstract

Thousands of small Open Reading Frames (smORFs) with the potential to encode small peptides of fewer than 100 amino acids exist in our genomes. However, the number of smORFs actually translated, and their molecular and functional roles are still unclear. Here we present a genome-wide assessment of smORF translation by ribosomal profiling of polysomal fractions in Drosophila. We detect two types of smORFs bound by multiple ribosomes and thus undergoing productive translation. The 'longer' smORFs of around 80 amino-acids resemble canonical proteins in translational metrics and conservation, and display a propensity to contain transmembrane motifs. The 'dwarf' smORFs are in general shorter (around 20 amino-acid long), are mostly found in 5'-UTRs and non-coding RNAs, are less well conserved and have no bioinformatic indicators of peptide function. Our findings indicate that thousands of smORFs are translated in metazoan genomes, reinforcing the idea that smORFs are an abundant and fundamental genome component.

Article and author information

Author details

  1. Julie L Aspden

    University of Sussex, Brighton, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Ying Chen Eyre-Walker

    University of Sussex, Brighton, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Rose J Philips

    University of Sussex, Brighton, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Unum Amin

    University of Sussex, Brighton, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  5. Muhammad Ali S Mumtaz

    University of Sussex, Brighton, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  6. Michele Brocard

    University of Sussex, Brighton, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  7. Juan-Pablo Couso

    University of Sussex, Brighton, United Kingdom
    For correspondence
    j.p.couso@sussex.ac.uk
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Thomas R Gingeras, Cold Spring Harbor Laboratory, United States

Publication history

  1. Received: May 30, 2014
  2. Accepted: August 19, 2014
  3. Accepted Manuscript published: August 21, 2014 (version 1)
  4. Version of Record published: September 16, 2014 (version 2)

Copyright

© 2014, Aspden 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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