Adaptive introgression facilitates adaptation to high latitudes in European aspen (Populus tremula L.)

Rendón-Anaya, M. et al. (2021) Adaptive introgression facilitates adaptation to high latitudes in European aspen (Populus tremula L.). Molecular Biology and Evolution, 38(11), pp. 5034-5050. (doi: 10.1093/molbev/msab229) (PMID:34329481) (PMCID:PMC8557470)

[img] Text
249103.pdf - Published Version
Available under License Creative Commons Attribution.

1MB

Abstract

Understanding local adaptation has become a key research area given the ongoing climate challenge and the concomitant requirement to conserve genetic resources. Perennial plants, such as forest trees, are good models to study local adaptation given their wide geographic distribution, largely outcrossing mating systems and demographic histories. We evaluated signatures of local adaptation in European aspen (Populus tremula) across Europe by means of whole genome re-sequencing of a collection of 411 individual trees. We dissected admixture patterns between aspen lineages and observed a strong genomic mosaicism in Scandinavian trees, evidencing different colonization trajectories into the peninsula from Russia, Central and Western Europe. As a consequence of the secondary contacts between populations after the last glacial maximum (LGM), we detected an adaptive introgression event in a genome region of ∼500kb in chromosome 10, harboring a large-effect locus that has previously been shown to contribute to adaptation to the short growing seasons characteristic of northern Scandinavia. Demographic simulations and ancestry inference suggest an Eastern origin - probably Russian - of the adaptive Nordic allele which nowadays is present in a homozygous state at the north of Scandinavia. The strength of introgression and positive selection signatures in this region is a unique feature in the genome. Furthermore, we detected signals of balancing selection, shared across regional populations, that highlight the importance of standing variation as a primary source of alleles that facilitate local adaptation. Our results therefore emphasize the importance of migration-selection balance underlying the genetic architecture of key adaptive quantitative traits.

Item Type:Articles
Additional Information:S.J., K.M.R., and N.R.S. are supported by the Trees for the Future (T4F) project. P.K.I., S.J., and K.M.R. are supported by the Knut and Alice Wallenberg Foundation (KAW). The research was also supported by grants from the Swedish Research Council (VR) to P.K.I. and to S.J., and by Formas to S.J. Part of the data generated for the study was supported by Science for Life Laboratory and the National Genomics Infrastructure (NGI, as a SciLifeLab National project) which provided access to massive parallel sequencing. All analyses were performed on resources provided by the Swedish National Infrastructure for Computing (SNIC) at Uppsala Multidisciplinary Centre for Advanced Computational Science (UPPMAX) under compute projects 2017/7-219, 2018/3-552, 2019/3-597, 2020/5-621 and storage projects sllstore2017050, sllstore2017059.
Status:Published
Refereed:Yes
Glasgow Author(s) Enlighten ID:Bailey, Dr Mark
Authors: Rendón-Anaya, M., Wilson, J., Sveinsson, S., Fedorkov, A., Cottrell, J., Bailey, M. E.S., Ruņģis, D., Lexer, C., Jansson, S., Robinson, K. M., Street, N. R., and Ingvarsson, P. K.
College/School:College of Medical Veterinary and Life Sciences > School of Life Sciences
College of Medical Veterinary and Life Sciences > School of Molecular Biosciences
Journal Name:Molecular Biology and Evolution
Publisher:Oxford University Press
ISSN:1537-1719
ISSN (Online):1537-1719
Published Online:30 July 2021
Copyright Holders:Copyright © 2021 The Authors
First Published:First published in Molecular Biology and Evolution 38(11): 5034-5050
Publisher Policy:Reproduced under a Creative Commons License

University Staff: Request a correction | Enlighten Editors: Update this record