Emergence of a floral colour polymorphism by pollinator-mediated overdominance
- Author(s)
- Roman T. Kellenberger, Kelsey J. R. P. Byers, Rita M. De Brito Francisco, Yannick M. Staedler, Amy M. LaFountain, Jürg Schönenberger, Florian P. Schiestl, Philipp M. Schlüter
- Abstract
Maintenance of polymorphism by overdominance (heterozygote advantage) is a fundamental concept in evolutionary biology. In most examples known in nature, overdominance is a result of homozygotes suffering from deleterious effects. Here we show that overdominance maintains a non-deleterious polymorphism with black, red and white floral morphs in the Alpine orchid Gymnadenia rhellicani. Phenotypic, metabolomic and transcriptomic analyses reveal that the morphs differ solely in cyanidin pigments, which are linked to differential expression of an anthocyanidin synthase (ANS) gene. This expression difference is caused by a premature stop codon in an ANS-regulating R2R3-MYB transcription factor, which is heterozygous in the red colour morph. Furthermore, field observations show that bee and fly pollinators have opposite colour preferences; this results in higher fitness (seed set) of the heterozygous morph without deleterious effects in either homozygous morph. Together, these findings demonstrate that genuine overdominance exists in nature.
- Organisation(s)
- Department of Botany and Biodiversity Research
- External organisation(s)
- Universität Zürich (UZH), University of Connecticut, Universität Hohenheim
- Journal
- Nature Communications
- Volume
- 10
- No. of pages
- 11
- ISSN
- 2041-1723
- DOI
- https://doi.org/10.1038/s41467-018-07936-x
- Publication date
- 2019
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 106008 Botany, 106012 Evolutionary research, 106042 Systematic botany
- Keywords
- ASJC Scopus subject areas
- Physics and Astronomy(all), Chemistry(all), Biochemistry, Genetics and Molecular Biology(all)
- Portal url
- https://ucris.univie.ac.at/portal/en/publications/emergence-of-a-floral-colour-polymorphism-by-pollinatormediated-overdominance(765e4342-23f0-4958-848f-c0581cc38d3f).html