Effects of colonization processes on genetic diversity: differences between annual plants and tree species.

International audience, Tree species are striking for their high within-population diversity and low among-population differentiation for nuclear genes. In contrast, annual plants show much more differentiation for nuclear genes but much less diversity than trees. The usual explanation for this difference is that pollen flow, and therefore gene flow, is much higher for trees. This explanation is problematic because it relies on equilibrium hypotheses. Because trees have very recently recolonized temperate areas, they have experienced many foundation events, which usually reduce within-population diversity and increase differentiation. Only extremely high levels of gene flow could counterbalance these successive founder effects. We develop a model to study the impact of life cycle of forest trees, in particular of the length of their juvenile phase, on genetic diversity and differentiation during the glacial period and the following colonization period. We show that both a reasonably high level of pollen flow and the life-cycle characteristics of trees are needed to explain the observed structure of genetic diversity. We also show that gene flow and life cycle both have an impact on maternally inherited cytoplasmic genes, which are characterized both in trees and annual species by much less diversity and much more differentiation than nuclear genes.

Auteurs du document :

Austerlitz, Frédéric, Mariette, Stéphanie, Machon, Nathalie, Gouyon, Pierre‐henri, Godelle, Bernard, Eco-Anthropologie et Ethnobiologie (EAE) ; Muséum national d'Histoire naturelle (MNHN)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institut national de recherches archéologiques (INRA), Conservatoire Botanique National du Bassin Parisien (CBNBP) ; Muséum national d'Histoire naturelle (MNHN), Institut de Systématique, Evolution, Biodiversité (ISYEB) ; Muséum national d'Histoire naturelle (MNHN)-École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université des Antilles (UA), Génome, populations, interactions, adaptation (GPIA) ; Université Montpellier 2 - Sciences et Techniques (UM2)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)

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CCSD

Mots clés :

MESH: Evolution, Molecular, MESH: Genetic Variation, MESH: Models, Genetic, MESH: Models, Statistical, MESH: Trees, [SDV.GEN.GPO]Life Sciences [q-bio]/Genetics/Populations and Evolution [q-bio.PE]

Thème (issu du Text Mining) :

SCIENCES EXACTES SCIENCES HUMAINES

Date :

2000

Format :

text/xml

Identifiant Documentaire :

hal-00525770, DOI: 10.1093/genetics/154.3.1309, PUBMED: 10757772

Source :

ISSN: 0016-6731, Genetics, https://hal.science/hal-00525770, Genetics, 2000, 154 (3), pp.1309-1321. ⟨10.1093/genetics/154.3.1309⟩

Langue :

Anglais