Líffræðifélag Íslands
Líffræðiráðstefnan 2015

Erindi/veggspjald / Talk/poster E95

Population genomics of a lichen symbiosis along a climatic gradient

Kristen Marie Westfall (1), Silke Werth (1,2), Hörður Guðmundsson (1), Zophonías Oddur Jónsson (1), Ólafur Sigmar Andrésson (1)

1. Institute of Life and Environmental Sciences, University of Iceland, Iceland, 2. Institute of Plant Sciences, University of Graz, Austria

Kynnir / Presenter: Kristen Marie Westfall

Tengiliður / Corresponding author: Silke Werth (silke.werth@uni-graz.at)

Adaptive genetic variation at the landscape level may be used as a proxy to assess species responses to climate change. Single-nucleotide polymorphisms (SNPs) in genes with a functional relationship to specific environmental conditions are the most likely candidates to detect loci of selective relevance. Patterns of genetic substructure and gene flow provide insight into the rate at which adaptive variation can permeate populations at multiple spatial scales. The lichen Peltigera membranacea is a fungal (mycobiont) and cyanobacterial (photobiont) symbiosis. The main objectives of this study were to identify genes under selection that are correlated with climatic factors and to quantify the rate and direction of gene flow among populations of P. membranacea in Iceland in order to assess the potential response of this species to climate change. Large scale SNP data sets were generated using RAD-sequencing of populations in Northeast and Southwest Iceland. SNPs under selection were identified using FST outlier methods and latent factor mixed models to investigate selection patterns with respect to climatic variables. Geographic patterns of neutral and non-neutral genomic structure will be discussed with respect to the potential responses of this species and other lichens to future climate scenarios.