Evidence for suppression of immunity as a driver for genomic introgressions and host range expansion in races of Albugo candida, a generalist parasite

  1. Mark McMullan
  2. Anastasia Gardiner
  3. Kate Bailey
  4. Eric Kemen
  5. Ben J Ward
  6. Volkan Cevik
  7. Alexandre Robert-Seilaniantz
  8. Torsten Schultz-Larsen
  9. Alexi Balmuth
  10. Eric Holub
  11. Cock van Oosterhout
  12. Jonathan D G Jones  Is a corresponding author
  1. The Sainsbury Laboratory, United Kingdom
  2. Max Planck Institute for Plant Breeding Research, Germany
  3. University of East Anglia, United Kingdom
  4. J.R. Simplot Company, United States
  5. University of Warwick, School of Life Sciences, United Kingdom

Abstract

How generalist parasites with wide host ranges can evolve is a central question in parasite evolution. Albugo candida is an obligate biotrophic parasite that consists of many physiological races that each specialize on distinct Brassicaceae host species. By analyzing genome sequence assemblies of five isolates, we show they represent three races that are genetically diverged by ~1%. Despite this divergence, their genomes are mosaic-like, with ~25% being introgressed from other races. Sequential infection experiments show that infection by adapted races enables subsequent infection of hosts by normally non-infecting races. This facilitates introgression and the exchange of effector repertoires, and may enable the evolution of novel races that can undergo clonal population expansion on new hosts. We discuss recent studies on hybridization in other eukaryotes such as yeast, Heliconius butterflies, Darwin's finches, sunflowers and cichlid fishes, and the implications of introgression for pathogen evolution in an agro-ecological environment.

Article and author information

Author details

  1. Mark McMullan

    The Sainsbury Laboratory, Norwich, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Anastasia Gardiner

    The Sainsbury Laboratory, Norwich, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Kate Bailey

    The Sainsbury Laboratory, Norwich, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Eric Kemen

    Max Planck Research Group Fungal Biodiversity, Max Planck Institute for Plant Breeding Research, Cologne, Germany
    Competing interests
    The authors declare that no competing interests exist.
  5. Ben J Ward

    School of Environmental Sciences, University of East Anglia, Norwich, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  6. Volkan Cevik

    The Sainsbury Laboratory, Norwich, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  7. Alexandre Robert-Seilaniantz

    The Sainsbury Laboratory, Norwich, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  8. Torsten Schultz-Larsen

    The Sainsbury Laboratory, Norwich, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  9. Alexi Balmuth

    J.R. Simplot Company, Boise, United States
    Competing interests
    The authors declare that no competing interests exist.
  10. Eric Holub

    Warwick Crop Centre, University of Warwick, School of Life Sciences, Warwick, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  11. Cock van Oosterhout

    School of Environmental Sciences, University of East Anglia, Norwich, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  12. Jonathan D G Jones

    The Sainsbury Laboratory, Norwich, United Kingdom
    For correspondence
    jonathan.jones@sainsbury-laboratory.ac.uk
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Detlef Weigel, Max Planck Institute for Developmental Biology, Germany

Publication history

  1. Received: September 1, 2014
  2. Accepted: February 26, 2015
  3. Accepted Manuscript published: February 27, 2015 (version 1)
  4. Version of Record published: April 2, 2015 (version 2)

Copyright

© 2015, McMullan 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. Mark McMullan
  2. Anastasia Gardiner
  3. Kate Bailey
  4. Eric Kemen
  5. Ben J Ward
  6. Volkan Cevik
  7. Alexandre Robert-Seilaniantz
  8. Torsten Schultz-Larsen
  9. Alexi Balmuth
  10. Eric Holub
  11. Cock van Oosterhout
  12. Jonathan D G Jones
(2015)
Evidence for suppression of immunity as a driver for genomic introgressions and host range expansion in races of Albugo candida, a generalist parasite
eLife 4:e04550.
https://doi.org/10.7554/eLife.04550

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