Synergistic assembly of human pre-spliceosomes across introns and exons

  1. Joerg E Braun
  2. Larry J Friedman
  3. Jeff Gelles  Is a corresponding author
  4. Melissa J Moore  Is a corresponding author
  1. University of Massachusetts Medical School, United States
  2. Brandeis University, United States

Abstract

Most human genes contain multiple introns, necessitating mechanisms to effectively define exons and ensure their proper connection by spliceosomes. Human spliceosome assembly involves both cross-intron and cross-exon interactions, but how these work together is unclear. We examined in human nuclear extracts dynamic interactions of single pre-mRNA molecules with individual fluorescently tagged spliceosomal subcomplexes to investigate how cross-intron and cross-exon processes jointly promote pre-spliceosome assembly. U1 subcomplex bound to the 5' splice site of an intron acts jointly with U1 bound to the 5' splice site of the next intron to dramatically increase the rate and efficiency by which U2 subcomplex is recruited to the branch site/3' splice site of the upstream intron. The flanking 5' splice sites have greater than additive effects implying distinct mechanisms facilitating U2 recruitment. This synergy of 5' splice sites across introns and exons is likely important in promoting correct and efficient splicing of multi-intron pre-mRNAs.

Data availability

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

Article and author information

Author details

  1. Joerg E Braun

    RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8309-6401
  2. Larry J Friedman

    Department of Biochemistry, Brandeis University, Waltham, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-4946-8731
  3. Jeff Gelles

    Department of Biochemistry, Brandeis University, Waltham, United States
    For correspondence
    gelles@brandeis.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-7910-3421
  4. Melissa J Moore

    RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, United States
    For correspondence
    melissa.moore@umassmed.edu
    Competing interests
    The authors declare that no competing interests exist.

Funding

National Institutes of Health (R01 GM053007)

  • Melissa J Moore

Human Frontier Science Program (LT000166/2013)

  • Joerg E Braun

European Molecular Biology Organization (ALTF 890-2012)

  • Joerg E Braun

Howard Hughes Medical Institute

  • Melissa J Moore

National Institutes of Health (R01 GM081648)

  • Jeff Gelles

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

Reviewing Editor

  1. Timothy W Nilsen, Case Western Reserve University, United States

Version history

  1. Received: April 21, 2018
  2. Accepted: June 12, 2018
  3. Accepted Manuscript published: June 22, 2018 (version 1)
  4. Version of Record published: July 6, 2018 (version 2)

Copyright

© 2018, Braun 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. Joerg E Braun
  2. Larry J Friedman
  3. Jeff Gelles
  4. Melissa J Moore
(2018)
Synergistic assembly of human pre-spliceosomes across introns and exons
eLife 7:e37751.
https://doi.org/10.7554/eLife.37751

Share this article

https://doi.org/10.7554/eLife.37751

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