Splicing factors Sf3A2 and Prp31 have direct roles in mitotic chromosome segregation

Abstract

Several studies have shown that RNAi-mediated depletion of splicing factors (SFs) results in mitotic abnormalities. However, it is currently unclear whether these abnormalities reflect defective splicing of specific pre-mRNAs or a direct role of the SFs in mitosis. Here we show that two highly conserved SFs, Sf3A2 and Prp31, are required for chromosome segregation in both Drosophila and human cells. Injections of anti-Sf3A2 and anti-Prp31 antibodies into Drosophila embryos disrupt mitotic division within 1 minute, arguing strongly against a splicing-related mitotic function of these factors. We demonstrate that both SFs bind spindle microtubules (MTs) and the Ndc80 complex, which in Sf3A2- and Prp31-depleted cells is not tightly associated with the kinetochores; in HeLa cells the Ndc80/HEC1-SF interaction is restricted to the M phase. These results indicate that Sf3A2 and Prp31 directly regulate interactions among kinetochores, spindle microtubules and the Ndc80 complex in both Drosophila and human cells.

Data availability

All data generated or analyzed during this study are included in the manuscript and Supplementary File 1. The full dataset for proteomic analyses reported in Figures 6 and Supplementary File 1 can be found at https://www.thewakefieldlab.com/ms; the significantly reduced protein IDs for each RNAi experiment were interrogated using a Gene Ontology (GO) classifier (GOTermMapper (https://go.princeton.edu/cgi-bin/GOTermMapper), concentrating on the GO terms ""cell division"" (GO:0051301), ""mitotic cell cycle"" (GO:0000278) and ""chromosome segregation"" (GO:0007059). Source data files have been provided for Figures 1, 4, 5, 7, 8, and 9.

Article and author information

Author details

  1. Claudia Pellacani

    Department of Biology and Biotechnology Charles Darwin, University of Rome, Rome, Italy
    Competing interests
    The authors declare that no competing interests exist.
  2. Elisabetta Bucciarelli

    Institute of Molecular Biology and Pathology, University of Rome, Rome, Italy
    Competing interests
    The authors declare that no competing interests exist.
  3. Fioranna Renda

    Department of Biology and Biotechnology Charles Darwin, University of Rome, Rome, Italy
    Competing interests
    The authors declare that no competing interests exist.
  4. Daniel Hayward

    Biosciences/Living Systems Institute, University of Exeter, Exeter, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  5. Antonella Palena

    Institute of Molecular Biology and Pathology, University of Rome, Rome, Italy
    Competing interests
    The authors declare that no competing interests exist.
  6. Jack Chen

    Biosciences/Living Systems Institute, University of Exeter, Exeter, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  7. Silvia Bonaccorsi

    Department of Biology and Biotechnology Charles Darwin, University of Rome, Roma, Italy
    Competing interests
    The authors declare that no competing interests exist.
  8. James G Wakefield

    Biosciences/Living Systems Institute, University of Exeter, Exeter, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  9. Maurizio Gatti

    Department of Biology and Biotechnology Charles Darwin, University of Rome, Rome, Italy
    For correspondence
    maurizio.gatti@uniroma1.it
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-3777-300X
  10. Maria Patrizia Somma

    Institute of Molecular Biology and Pathology, University of Rome, Rome, Italy
    For correspondence
    patrizia.somma@uniroma1.it
    Competing interests
    The authors declare that no competing interests exist.

Funding

Associazione Italiana per la Ricerca sul Cancro (IG16020)

  • Maurizio Gatti

Ministero dell'Istruzione, dell'Università e della Ricerca

  • Silvia Bonaccorsi

Biotechnology and Biological Sciences Research Council (BB/K017837/1)

  • James G Wakefield

Associazione Italiana per la Ricerca sul Cancro (IG20528)

  • Maurizio Gatti

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

Reviewing Editor

  1. Jon Pines, Institute of Cancer Research Research, United Kingdom

Publication history

  1. Received: July 22, 2018
  2. Accepted: November 14, 2018
  3. Accepted Manuscript published: November 26, 2018 (version 1)
  4. Version of Record published: December 10, 2018 (version 2)

Copyright

© 2018, Pellacani 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. Claudia Pellacani
  2. Elisabetta Bucciarelli
  3. Fioranna Renda
  4. Daniel Hayward
  5. Antonella Palena
  6. Jack Chen
  7. Silvia Bonaccorsi
  8. James G Wakefield
  9. Maurizio Gatti
  10. Maria Patrizia Somma
(2018)
Splicing factors Sf3A2 and Prp31 have direct roles in mitotic chromosome segregation
eLife 7:e40325.
https://doi.org/10.7554/eLife.40325

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