Asymmetrical diversification of the receptor-ligand interaction controlling self-incompatibility in Arabidopsis
- CNRS, Université de Lille, France
Abstract
How two-component genetic systems accumulate evolutionary novelty and diversify in the course of evolution is a fundamental problem in evolutionary systems biology. In the Brassicaceae, self-incompatibility (SI) is a spectacular example of a diversified allelic series in which numerous highly diverged receptor-ligand combinations are segregating in natural populations. However, the evolutionary mechanisms by which new SI specificities arise have remained elusive. Using in planta ancestral protein reconstruction, we demonstrate that two allelic variants segregating as distinct receptor-ligand combinations diverged through an asymmetrical process whereby one variant has retained the same recognition specificity as their (now extinct) putative ancestor, while the other has functionally diverged and now represents a novel specificity no longer recognized by the ancestor. Examination of the structural determinants of the shift in binding specificity suggests that qualitative rather than quantitative changes of the interaction are an important source of evolutionary novelty in this highly diversified receptor-ligand system.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
Article and author information
Author details
Guillaume Brysbaert
Funding
H2020 European Research Council (Novel project grant #648321)
- Vincent Castric
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2019, Chantreau 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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Asymmetrical diversification of the receptor-ligand interaction controlling self-incompatibility in Arabidopsis
eLife 8:e50253.
https://doi.org/10.7554/eLife.50253
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