Selections that isolate recombinant mitochondrial genomes in animals

  1. Hansong Ma
  2. Patrick H O'Farrell  Is a corresponding author
  1. University of California, San Francisco, United States

Abstract

Homologous recombination is widespread and catalyzes evolution. Nonetheless, its existence in animal mitochondrial DNA is questioned. We designed selections for recombination between co-resident mitochondrial genomes in various heteroplasmic Drosophila lines. In four experimental settings, recombinant genomes became the sole or dominant genome in the progeny. Thus, selection uncovers occurrence of homologous recombination in Drosophila mtDNA and documents its functional benefit. Double-strand breaks enhanced recombination in the germ line and revealed somatic recombination. When the recombination partner was a diverged D. melanogaster genome or a genome from a different species such as D. yakuba, sequencing revealed long continuous stretches of exchange. In addition, the distribution of sequence polymorphisms in recombinants allowed us to map a selected trait to a particular region in the Drosophila mitochondrial genome. Thus, recombination can be harnessed to dissect function and evolution of mitochondrial genome.

Article and author information

Author details

  1. Hansong Ma

    Department of Biochemistry, University of California, San Francisco, San Francisco, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Patrick H O'Farrell

    Department of Biochemistry, University of California, San Francisco, San Francisco, United States
    For correspondence
    ofarrell@cgl.ucsf.edu
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Jodi Nunnari, University of California, Davis, United States

Publication history

  1. Received: February 28, 2015
  2. Accepted: August 1, 2015
  3. Accepted Manuscript published: August 3, 2015 (version 1)
  4. Version of Record published: September 28, 2015 (version 2)

Copyright

© 2015, Ma & O'Farrell

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. Hansong Ma
  2. Patrick H O'Farrell
(2015)
Selections that isolate recombinant mitochondrial genomes in animals
eLife 4:e07247.
https://doi.org/10.7554/eLife.07247

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