A bend, flip and trap mechanism for transposon integration

  1. Elizabeth R Morris
  2. Heather Grey
  3. Grant McKenzie
  4. Anita C Jones
  5. Julia M Richardson  Is a corresponding author
  1. The Francis Crick Institute, United Kingdom
  2. University of Edinburgh, United Kingdom
  3. EaStCHEM School of Chemistry, United Kingdom

Abstract

Cut-and-paste DNA transposons of the mariner/Tc1 family are useful tools for genome engineering and are inserted specifically at TA target sites. A crystal structure of the mariner transposase Mos1 (derived from Drosophila mauritiana), in complex with transposon ends covalently joined to target DNA, portrays the transposition machinery after DNA integration. It reveals severe distortion of target DNA and flipping of the target adenines into extra-helical positions. Fluorescence experiments confirm dynamic base flipping in solution. Transposase residues W159, R186, F187 and K190 stabilise the target DNA distortions and are required for efficient transposon integration and transposition in vitro. Transposase recognises the flipped target adenines via base-specific interactions with backbone atoms, offering a molecular basis for TA target sequence selection. Our results will provide a template for re-designing mariner/Tc1 transposases with modified target specificities.

Article and author information

Author details

  1. Elizabeth R Morris

    Mill Hill Laboratory, The Francis Crick Institute, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Heather Grey

    Institute of Quantitative Biology, Biochemistry and Biotechnology, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Grant McKenzie

    EaStCHEM School of Chemistry, Edinburgh, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Anita C Jones

    EaStCHEM School of Chemistry, Edinburgh, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  5. Julia M Richardson

    Institute of Quantitative Biology, Biochemistry and Biotechnology, School of Biological Sciences, University of Edinburgh, Edinburgh, United Kingdom
    For correspondence
    jrichard@staffmail.ed.ac.uk
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. David Sherratt, University of Oxford, United Kingdom

Version history

  1. Received: February 24, 2016
  2. Accepted: May 24, 2016
  3. Accepted Manuscript published: May 25, 2016 (version 1)
  4. Version of Record published: June 24, 2016 (version 2)

Copyright

© 2016, Morris 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. Elizabeth R Morris
  2. Heather Grey
  3. Grant McKenzie
  4. Anita C Jones
  5. Julia M Richardson
(2016)
A bend, flip and trap mechanism for transposon integration
eLife 5:e15537.
https://doi.org/10.7554/eLife.15537

Share this article

https://doi.org/10.7554/eLife.15537

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