Letter | Published:

Horizontal genome transfer as an asexual path to the formation of new species

Nature volume 511, pages 232235 (10 July 2014) | Download Citation

Abstract

Allopolyploidization, the combination of the genomes from two different species, has been a major source of evolutionary innovation and a driver of speciation and environmental adaptation1,2,3,4. In plants, it has also contributed greatly to crop domestication, as the superior properties of many modern crop plants were conferred by ancient allopolyploidization events5,6. It is generally thought that allopolyploidization occurred through hybridization events between species, accompanied or followed by genome duplication6,7. Although many allopolyploids arose from closely related species (congeners), there are also allopolyploid species that were formed from more distantly related progenitor species belonging to different genera or even different tribes8. Here we have examined the possibility that allopolyploidization can also occur by asexual mechanisms. We show that upon grafting—a mechanism of plant–plant interaction that is widespread in nature—entire nuclear genomes can be transferred between plant cells. We provide direct evidence for this process resulting in speciation by creating a new allopolyploid plant species from a herbaceous species and a woody species in the nightshade family. The new species is fertile and produces fertile progeny. Our data highlight natural grafting as a potential asexual mechanism of speciation and also provide a method for the generation of novel allopolyploid crop species.

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Acknowledgements

We thank the MPI-MP Green Team for help with plant transformation, K. Köhl for providing the hpt vector and S. Ruf (MPI-MP) for discussions. We are grateful to J. Fuchs (IPK Gatersleben) for advice on flow cytometry measurements. This research was financed by the Max Planck Society.

Author information

Author notes

    • Ignacia Fuentes
    •  & Sandra Stegemann

    These authors contributed equally to this work.

Affiliations

  1. Max-Planck-Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, D-14476 Potsdam-Golm, Germany

    • Ignacia Fuentes
    • , Sandra Stegemann
    • , Daniel Karcher
    •  & Ralph Bock
  2. Department of Molecular Biology, Institute of Biotechnology, John Paul II Catholic University of Lublin, Konstantynow 1I, 20-708 Lublin, Poland

    • Hieronim Golczyk

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Contributions

I.F., S.S. and H.G. performed the experiments. All authors participated in data evaluation and experimental design. R.B. conceived the study, and wrote the manuscript.

Competing interests

The authors declare no competing financial interests.

Corresponding author

Correspondence to Ralph Bock.

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https://doi.org/10.1038/nature13291

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