Non-allelic gene conversion enables rapid evolutionary change at multiple regulatory sites encoded by transposable elements

  1. Christopher E Ellison
  2. Doris Bachtrog  Is a corresponding author
  1. University of California, Berkeley, United States

Abstract

Transposable elements (TEs) allow rewiring of regulatory networks, and the recent amplification of the ISX-element dispersed 77 functional but suboptimal binding-sites for the dosage-compensation-complex to a newly-formed X-chromosome in Drosophila. Here we identify two linked refining-mutations within ISX that interact epistatically to increase binding affinity to the dosage-compensation-complex. Selection has increased the frequency of this derived haplotype in the population, which is fixed at 30% of ISX-insertions and polymorphic among another 41%. Sharing of this haplotype indicates that high levels of gene-conversion among ISX-elements allow them to 'crowd-source' refining-mutations, and a refining-mutation that occurs at any single ISX-element can spread in two dimensions: horizontally across insertion sites by non-allelic gene-conversion, and vertically through the population by natural selection. These describes a novel route how fully functional regulatory elements can arise rapidly from TEs and implicate non-allelic gene-conversion as having an important role in accelerating the evolutionary fine-tuning of regulatory networks.

Article and author information

Author details

  1. Christopher E Ellison

    Department of Integrative Biology, University of California, Berkeley, Berkeley, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Doris Bachtrog

    Department of Integrative Biology, University of California, Berkeley, Berkeley, United States
    For correspondence
    dbachtrog@berkeley.edu
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Magnus Nordborg, Gregor Mendel Institute of Molecular Plant Biology, Austrian Academy of Sciences, Austria

Version history

  1. Received: December 4, 2014
  2. Accepted: February 16, 2015
  3. Accepted Manuscript published: February 17, 2015 (version 1)
  4. Version of Record published: April 2, 2015 (version 2)

Copyright

© 2015, Ellison & Bachtrog

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. Christopher E Ellison
  2. Doris Bachtrog
(2015)
Non-allelic gene conversion enables rapid evolutionary change at multiple regulatory sites encoded by transposable elements
eLife 4:e05899.
https://doi.org/10.7554/eLife.05899

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https://doi.org/10.7554/eLife.05899

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