Titre :

Madeiran Arabidopsis thaliana Reveals Ancient Long-Range Colonization and Clarifies Demography in Eurasia

Auteur(s) :

Fulgione, Andrea [Auteur]
Koornneef, Maarten [Auteur]
Max Planck Institute for Plant Breeding Research [MPIPZ]
Roux, Fabrice [Auteur]
Évolution, Écologie et Paléontologie (Evo-Eco-Paleo) - UMR 8198 [Evo-Eco-Paléo (EEP)]
Hermisson, Joachim [Auteur]
Hancock, Angela [Auteur]

Titre de la revue :

Molecular Biology and Evolution

Pagination :

564-574

Éditeur :

Oxford University Press (OUP)

Date de publication :

2018-03-01

ISSN :

0737-4038

Mot(s)-clé(s) :

population genetics
relict
admixture

Mot(s)-clé(s) en anglais :

demography
Arabidopsis thaliana
island

Discipline(s) HAL :

Sciences du Vivant [q-bio]/Génétique/Génétique des populations [q-bio.PE]

Résumé en anglais : [en]

The study of model organisms on islands may shed light on rare long-range dispersal events, uncover signatures of local evolutionary processes, and inform demographic inference on the mainland. Here, we sequenced the genomes ...
Lire la suite >The study of model organisms on islands may shed light on rare long-range dispersal events, uncover signatures of local evolutionary processes, and inform demographic inference on the mainland. Here, we sequenced the genomes of Arabidopsis thaliana samples from the oceanic island of Madeira. These samples include the most diverged worldwide, likely a result of long isolation on the island. We infer that colonization of Madeira happened between 70 and 85 ka, consistent with a propagule dispersalmodel (of size >= 10), or with an ecological window of opportunity. This represents a clear example of a natural long-range dispersal event in A. thaliana. Long-term effective population size on the island, rather than the founder effect, had the greatest impact on levels of diversity, and rates of coalescence. Our results uncover a selective sweep signature on the ancestral haplotype of a known translocation in Eurasia, as well as the possible importance of the low phosphorous availability in volcanic soils, and altitude, in shaping early adaptations to the island conditions. Madeiran genomes, sheltered from the complexities of continental demography, help illuminate ancient demographic events in Eurasia. Our data support a model in which two separate lineages of A. thaliana, one originating in Africa and the other from the Caucasus expanded and met in Iberia, resulting in a secondary contact zone there. Although previous studies inferred that the westward expansion of A. thaliana coincided with the spread of human agriculture, our results suggest that it happened much earlier (20-40 ka).Lire moins >

Langue :

Anglais

Vulgarisation :

Non

Projet ANR :

Université Fédérale de Toulouse

Collections :

• Évolution, Écologie et Paléontologie (Evo Eco Paleo) - UMR 8198

Source :

Harvested from HAL