1. Chromosomes and Gene Expression
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Kinetic competition during the transcription cycle results in stochastic RNA processing

  1. Antoine Coulon
  2. Matthew L Ferguson
  3. Valeria de Turris
  4. Murali Palangat
  5. Carson C Chow
  6. Daniel R Larson  Is a corresponding author
  1. National Institutes of Health, United States
  2. Boise State University, United States
  3. Istituto Italiano di Tecnologia, Italy
  4. National Cancer Institute, National Institutes of Health, United States
Research Article
  • Cited 91
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Cite this article as: eLife 2014;3:e03939 doi: 10.7554/eLife.03939
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Abstract

Synthesis of mRNA in eukaryotes involves the coordinated action of many enzymatic processes, including initiation, elongation, splicing and cleavage. Kinetic competition between these processes has been proposed to determine RNA fate, yet such coupling has never been observed in vivo on single transcripts. Here, we use dual-color single-molecule RNA imaging in living human cells to construct a complete kinetic profile of transcription and splicing of the β-globin gene. We find that kinetic competition results in multiple competing pathways for pre-mRNA splicing. Splicing of the terminal intron occurs stochastically both before and after transcript release, indicating there is not a strict quality control checkpoint. The majority of pre-mRNAs are spliced after release, while diffusing away from the site of transcription. A single missense point mutation (S34F) in the essential splicing factor U2AF1 which occurs in human cancers perturbs this kinetic balance and defers splicing to occur entirely post-release.

Article and author information

Author details

  1. Antoine Coulon

    National Institutes of Health, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Matthew L Ferguson

    Boise State University, Boise, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Valeria de Turris

    Istituto Italiano di Tecnologia, Rome, Italy
    Competing interests
    The authors declare that no competing interests exist.
  4. Murali Palangat

    National Cancer Institute, National Institutes of Health, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Carson C Chow

    National Institutes of Health, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Daniel R Larson

    National Cancer Institute, National Institutes of Health, Bethesda, United States
    For correspondence
    dan.larson@nih.gov
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Douglas L Black, Howard Hughes Medical Institute, University of California, Los Angeles, United States

Publication history

  1. Received: July 11, 2014
  2. Accepted: October 1, 2014
  3. Accepted Manuscript published: October 1, 2014 (version 1)
  4. Version of Record published: October 28, 2014 (version 2)

Copyright

This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.

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