Characterisation of the biflavonoid hinokiflavone as a pre-mRNA splicing modulator that inhibits SENP

  1. Andrea Pawellek
  2. Ursula Ryder
  3. Triin Tammsalu
  4. Lewis J King
  5. Helmi Kreinin
  6. Tony Ly
  7. Ronald T Hay
  8. Richard Hartley
  9. Angus I Lamond  Is a corresponding author
  1. University of Dundee, United Kingdom
  2. WestCHEM School of Chemistry, University of Glasgow, United Kingdom

Abstract

We have identified the plant biflavonoid hinokiflavone as an inhibitor of splicing in vitro and modulator of alternative splicing in cells. Chemical synthesis confirms hinokiflavone is the active molecule. Hinokiflavone inhibits splicing in vitro by blocking spliceosome assembly, leading to accumulation of the A complex. Cells treated with hinokiflavone show altered subnuclear organization specifically of splicing factors required for A complex formation, which relocalize together with SUMO1 and SUMO2 into enlarged nuclear speckles. Hinokiflavone increases protein SUMOylation levels, both in in vitro splicing reactions and in cells. Hinokiflavone also inhibited a purified, E. coli expressed SUMO protease, SENP1, in vitro, indicating the increase in SUMOylated proteins results primarily from inhibition of de-SUMOylation. Using a quantitative proteomics assay we identified many SUMO2 sites whose levels increased in cells following hinokiflavone treatment, with the major targets including 6 proteins that are components of the U2 snRNP and required for A complex formation.

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Article and author information

Author details

  1. Andrea Pawellek

    Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Ursula Ryder

    Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Triin Tammsalu

    Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Lewis J King

    WestCHEM School of Chemistry, University of Glasgow, Glasgow, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  5. Helmi Kreinin

    WestCHEM School of Chemistry, University of Glasgow, Glasgow, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  6. Tony Ly

    Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  7. Ronald T Hay

    Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  8. Richard Hartley

    WestCHEM School of Chemistry, University of Glasgow, Glasgow, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  9. Angus I Lamond

    Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom
    For correspondence
    a.i.lamond@dundee.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6204-6045

Funding

Wellcome (073980/Z/03/B)

  • Angus I Lamond

Wellcome (097045/B/11/Z)

  • Angus I Lamond

Wellcome (098391/Z/12/7)

  • Ronald T Hay

Wellcome (105606/Z/14/Z)

  • Ronald T Hay

European Commission (PITN-GA-2011-290257)

  • Triin Tammsalu

Engineering and Physical Sciences Research Council (EP/L50497X/1)

  • Lewis J King

Engineering and Physical Sciences Research Council (EP/L50497X/1)

  • Helmi Kreinin

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

Reviewing Editor

  1. Juan Valcárcel, Centre de Regulació Genòmica (CRG), Barcelona, Spain

Version history

  1. Received: April 2, 2017
  2. Accepted: September 6, 2017
  3. Accepted Manuscript published: September 8, 2017 (version 1)
  4. Version of Record published: September 28, 2017 (version 2)

Copyright

© 2017, Pawellek 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. Andrea Pawellek
  2. Ursula Ryder
  3. Triin Tammsalu
  4. Lewis J King
  5. Helmi Kreinin
  6. Tony Ly
  7. Ronald T Hay
  8. Richard Hartley
  9. Angus I Lamond
(2017)
Characterisation of the biflavonoid hinokiflavone as a pre-mRNA splicing modulator that inhibits SENP
eLife 6:e27402.
https://doi.org/10.7554/eLife.27402

Share this article

https://doi.org/10.7554/eLife.27402

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