Should we hail the Red King? Evolutionary consequences of a mutualistic lifestyle in genomes of lichenized ascomycetes
- Author:
- Ametrano C.G., Lumbsch H.T., Di Stefano I., Sangvichien E., Muggia L. & Grewe F.
- Year:
- 2022
- Journal:
- Ecology and Evolution
- Pages:
- 12: e8471 [16 p.]
- Url:
- https://doi.org/10.1002/ece3.8471
The Red Queen dynamic is often brought into play for antagonistic relationships.
However, the coevolutionary effects of mutualistic interactions, which predict slower
evolution for interacting organisms (Red King), have been investigated to a lesser extent. Lichens are a stable, mutualistic relationship of fungi and cyanobacteria and/
or algae, which originated several times independently during the evolution of fungi.
Therefore, they represent a suitable system to investigate the coevolutionary effect
of mutualism on the fungal genome. We measured substitution rates and selective
pressure of about 2000 protein-coding genes (plus the rDNA region) in two different
classes of Ascomycota, each consisting of closely related lineages of lichenized and
non-lichenized fungi. Our results show that independent lichenized clades are characterized by significantly slower rates for both synonymous and non-synonymous substitutions. We hypothesize that this evolutionary pattern is connected to the lichen
life cycle (longer generation time of lichenized fungi) rather than a result of different
selection strengths, which is described as the main driver for the Red Kind dynamic.
This first empirical evidence of slower evolution in lichens provides an important insight on how biotic cooperative interactions are able to shape the evolution of symbiotic organisms.
Keywords: coevolution, comparative genomics, evolutionary rate, lichenized fungi, Pyrenulales,
Trypetheliales.
- Id:
- 34097
- Submitter:
- zdenek
- Post_time:
- Friday, 14 January 2022 22:11