Demographic expansion and genetic load of the halophyte model plant Eutrema salsugineum
Abstract
The halophyte model plant Eutrema salsugineum (Brassicaceae) disjunctly occurs in temperate to subarctic Asia and North America. This vast, yet extremely discontinuous distribution constitutes an ideal system to examine long‐distance dispersal and the ensuing accumulation of deleterious mutations as expected in expanding populations of selfing plants. In this study, we re‐sequenced individuals from 23 populations across the range of E. salsugineum. Our population genomic data indicate that E. salsugineum migrated ‘out of the Altai region’ at least three times to colonize northern China, northeast Russia and western China. It then expanded its distribution into North America independently from northeast Russia and northern China, respectively. The species colonized northern China around 33.7 thousand years ago (kya) and underwent a considerable expansion in range size approximately 7‐8 kya. The western China lineage is likely a hybrid derivative of the northern China and Altai lineages, originating approximately 25‐30 kya. Deleterious alleles accumulated in a stepwise manner from (i) Altai to northern China and North America, and (ii) from Altai to northeast Russia and North America. In summary, E. salsugineum dispersed from Asia to North America and deleterious mutations accumulated in a stepwise manner during the expansion of the species’ distribution.
Citation
Wang , X-J , Hu , Q-J , Guo , X-Y , Wang , K , Ru , D-F , German , D A , Weretilnyk , E A , Abbott , R J , Lascoux , M & Liu , J-Q 2018 , ' Demographic expansion and genetic load of the halophyte model plant Eutrema salsugineum ' , Molecular Ecology , vol. 27 , no. 14 , pp. 2943-2955 . https://doi.org/10.1111/mec.14738
Publication
Molecular Ecology
Status
Peer reviewed
ISSN
0962-1083Type
Journal article
Rights
© 2018 John Wiley & Sons Ltd. This work has been made available online in accordance with the publisher’s policies. This is the author created, accepted version manuscript following peer review and may differ slightly from the final published version. The final published version of this work is available at https://doi.org/10.1111/mec.14738
Description
This work was supported by National Natural Science Foundation of China (31590821, 91331102, 91731301) and the Youth Science and Technology Innovation Team of Sichuan Province (2014TD003).Collections
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