Loading...
Demography and mating system shape the genome-wide impact of purifying selection in Arabis alpina
Laenen, B. Nowak, M.D. Toräng, P. Wunder, J. Wötsel, S. Steige, K.A. Kourmpetis, Y. Odong, T. Drouzas, A.D.
Laenen, B.
Nowak, M.D.
Toräng, P.
Wunder, J.
Wötsel, S.
Steige, K.A.
Kourmpetis, Y.
Odong, T.
Drouzas, A.D.
Publication Date
2018-01-23
End of Embargo
Supervisor
Rights
Peer-Reviewed
Yes
Open Access status
openAccess
Accepted for publication
Institution
Department
Awarded
Embargo end date
Collections
Abstract
Plant mating systems have profound effects on levels and structuring of genetic variation and can affect the impact of natural selection. Although theory predicts that intermediate outcrossing rates may allow plants to prevent accumulation of deleterious alleles, few studies have empirically tested this prediction using genomic data. Here, we study the effect of mating system on purifying selection by conducting population-genomic analyses on whole-genome resequencing data from 38 European individuals of the arctic-alpine crucifer Arabis alpina. We find that outcrossing and mixed-mating populations maintain genetic diversity at similar levels, whereas highly self-fertilizing Scandinavian A. alpina show a strong reduction in genetic diversity, most likely as a result of a postglacial colonization bottleneck. We further find evidence for accumulation of genetic load in highly self-fertilizing populations, whereas the genome-wide impact of purifying selection does not differ greatly between mixed-mating and outcrossing populations. Our results demonstrate that intermediate levels of outcrossing may allow efficient selection against harmful alleles, whereas demographic effects can be important for relaxed purifying selection in highly selfing populations. Thus, mating system and demography shape the impact of purifying selection on genomic variation in A. alpina. These results are important for an improved understanding of the evolutionary consequences of mating system variation and the maintenance of mixed-mating strategies.
Version
Accepted manuscript
Citation
Laenen B, Tedder A, Nowak MD et al (2018) Demography and mating system shape the genome-wide impact of purifying selection in Arabis alpina. Proceedings of the National Academy of Sciences. 115(4): 816-821.
Link to publisher’s version
Link to published version
Link to Version of Record
Type
Article
Qualification name
Notes
This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1707492115/-/DCSupplemental.