Adaptive differentiation coincides with local bioclimatic conditions along an elevational cline in populations of a lichen-forming fungus

BMC Evolutionary Biology

Research Article

Rahul Sharma¹  Burkhard Büdel²  Jürgen Otte³  Gregor Rolshausen³  Francesco Dal Grande³  Bagdevi Mishra³  Marco Thines³  Markus Pfenninger⁴  Anjuli Meiser⁴  Imke Schmitt⁴ 

[1] Institut für Ökologie, Evolution und Diversität, Goethe-Universität Frankfurt, Max-von-Laue-Str. 9, 60438, Frankfurt am Main, Germany;Plant Ecology and Systematics, Biology Department, University of Kaiserslautern, 67653, Kaiserslautern, Germany;Senckenberg Biodiversity and Climate Research Centre (BiK-F), Senckenberganlage 25, 60325, Frankfurt am Main, Germany;Senckenberg Biodiversity and Climate Research Centre (BiK-F), Senckenberganlage 25, 60325, Frankfurt am Main, Germany;Institut für Ökologie, Evolution und Diversität, Goethe-Universität Frankfurt, Max-von-Laue-Str. 9, 60438, Frankfurt am Main, Germany;

关键词: Adaptation;    Altitudinal;    Climate change;    Fungi;    Pool-Seq;    Population genomics;    Symbiosis;    SNP;    Gradient;   

DOI  :  10.1186/s12862-017-0929-8

 received in 2017-01-12, accepted in 2017-03-01,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundMany fungal species occur across a variety of habitats. Particularly lichens, fungi forming symbioses with photosynthetic partners, have evolved remarkable tolerances for environmental extremes. Despite their ecological importance and ubiquity, little is known about the genetic basis of adaption in lichen populations. Here we studied patterns of genome-wide differentiation in the lichen-forming fungus Lasallia pustulata along an altitudinal gradient in the Mediterranean region. We resequenced six populations as pools and identified highly differentiated genomic regions. We then detected gene-environment correlations while controlling for shared population history and pooled sequencing bias, and performed ecophysiological experiments to assess fitness differences of individuals from different environments.ResultsWe detected two strongly differentiated genetic clusters linked to Mediterranean and temperate-oceanic climate, and an admixture zone, which coincided with the transition between the two bioclimates. High altitude individuals showed ecophysiological adaptations to wetter and more shaded conditions. Highly differentiated genome regions contained a number of genes associated with stress response, local environmental adaptation, and sexual reproduction.ConclusionsTaken together our results provide evidence for a complex interplay between demographic history and spatially varying selection acting on a number of key biological processes, suggesting a scenario of ecological speciation.

【 授权许可】

CC BY   
© The Author(s). 2017