HAL will be down for maintenance from Friday, June 10 at 4pm through Monday, June 13 at 9am. More information
Skip to Main content Skip to Navigation
Journal articles

Genomic Signatures of a Major Adaptive Event in the Pathogenic Fungus Melampsora larici-populina

Abstract : The recent availability of genome-wide sequencing techniques has allowed systematic screening for molecular signatures of adaptation, including in nonmodel organisms. Host–pathogen interactions constitute good models due to the strong selective pressures that they entail. We focused on an adaptive event which affected the poplar rust fungus Melampsora larici-populina when it overcame a resistance gene borne by its host, cultivated poplar. Based on 76 virulent and avirulent isolates framing narrowly the estimated date of the adaptive event, we examined the molecular signatures of selection. Using an array of genome scan methods based on different features of nucleotide diversity, we detected a single locus exhibiting a consistent pattern suggestive of a selective sweep in virulent individuals (excess of differentiation between virulent and avirulent samples, linkage disequilibrium, genotype–phenotype statistical association, and long-range haplotypes). Our study pinpoints a single gene and further a single amino acid replacement which may have allowed the adaptive event. Although our samples are nearly contemporary to the selective sweep, it does not seem to have affected genome diversity further than the immediate vicinity of the causal locus, which can be explained by a soft selective sweep (where selection acts on standing variation) and by the impact of recombination in mitigating the impact of selection. Therefore, it seems that properties of the life cycle of M. larici-populina, which entails both high genetic diversity and outbreeding, has facilitated its adaptation.
Document type :
Journal articles
Complete list of metadata

Contributor : Sebastien Duplessis Connect in order to contact the contributor
Submitted on : Tuesday, May 17, 2022 - 4:44:52 PM
Last modification on : Saturday, May 21, 2022 - 3:51:55 AM


Publisher files allowed on an open archive


Distributed under a Creative Commons Attribution - NonCommercial 4.0 International License



Antoine Persoons, Agathe Maupetit, Clémentine Louet, Axelle Andrieux, Anna Lipzen, et al.. Genomic Signatures of a Major Adaptive Event in the Pathogenic Fungus Melampsora larici-populina. Genome Biology and Evolution, Society for Molecular Biology and Evolution, 2022, 14 (1), 14 p. ⟨10.1093/gbe/evab279⟩. ⟨hal-03606205⟩



Record views


Files downloads