Genetic isolation between two recently diverged populations of a symbiotic fungus.

Journal Article

Fungi are an omnipresent and highly diverse group of organisms, making up a significant part of eukaryotic diversity. Little is currently known about the drivers of fungal population differentiation and subsequent divergence of species, particularly in symbiotic, mycorrhizal fungi. Here, we investigate the population structure and environmental adaptation in Suillus brevipes (Peck) Kuntze, a wind-dispersed soil fungus that is symbiotic with pine trees. We assembled and annotated the reference genome for Su. brevipes and resequenced the whole genomes of 28 individuals from coastal and montane sites in California. We detected two clearly delineated coast and mountain populations with very low divergence. Genomic divergence was restricted to few regions, including a region of extreme divergence containing a gene encoding for a membrane Na(+) /H(+) exchanger known for enhancing salt tolerance in plants and yeast. Our results are consistent with a very recent split between the montane and coastal Su. brevipes populations, with few small genomic regions under positive selection and a pattern of dispersal and/or establishment limitation. Furthermore, we identify a putatively adaptive gene that motivates further functional analyses to link genotypes and phenotypes and shed light on the genetic basis of adaptive traits.

Full Text

Duke Authors

Cited Authors

  • Branco, S; Gladieux, P; Ellison, CE; Kuo, A; LaButti, K; Lipzen, A; Grigoriev, IV; Liao, H-L; Vilgalys, R; Peay, KG; Taylor, JW; Bruns, TD

Published Date

  • June 2015

Published In

Volume / Issue

  • 24 / 11

Start / End Page

  • 2747 - 2758

PubMed ID

  • 25728665

Electronic International Standard Serial Number (EISSN)

  • 1365-294X

International Standard Serial Number (ISSN)

  • 0962-1083

Digital Object Identifier (DOI)

  • 10.1111/mec.13132

Language

  • eng