title: Basidiomycete yeasts in the cortex of ascomycete macrolichens.
abstract: For over 140 years, lichens have been regarded as a symbiosis between a single fungus, usually an ascomycete, and a photosynthesizing partner. Other fungi have long been known to occur as occasional parasites or endophytes, but the one lichen-one fungus paradigm has seldom been questioned. Here we show that many common lichens are composed of the known ascomycete, the photosynthesizing partner, and, unexpectedly, specific basidiomycete yeasts. These yeasts are embedded in the cortex, and their abundance correlates with previously unexplained variations in phenotype. Basidiomycete lineages maintain close associations with specific lichen species over large geographical distances and have been found on six continents. The structurally important lichen cortex, long treated as a zone of differentiated ascomycete cells, appears to consistently contain two unrelated fungi.
authors.affiliation: Institute of Plant Sciences, NAWI Graz, University of Graz, 8010 Graz, Austria. Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA. toby.spribille@mso.umt.edu.
authors.forename: Toby
authors.initials: T
authors.lastname: Spribille
authors.affiliation: Department of Organismal Biology, Uppsala University, Norbyvägen 18D, 752 36 Uppsala, Sweden. Department of Ecology, Swedish University of Agricultural Sciences, Post Office Box 7044, SE-75007 Uppsala, Sweden.
authors.forename: Veera
authors.initials: V
authors.lastname: Tuovinen
authors.affiliation: Institute of Plant Sciences, NAWI Graz, University of Graz, 8010 Graz, Austria.
authors.forename: Philipp
authors.initials: P
authors.lastname: Resl
authors.affiliation: Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA.
authors.forename: Dan
authors.initials: D
authors.lastname: Vanderpool
authors.affiliation: Institute of Molecular Biosciences, BioTechMed-Graz, University of Graz, 8010 Graz, Austria.
authors.forename: Heimo
authors.initials: H
authors.lastname: Wolinski
authors.affiliation: Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: M Catherine
authors.initials: MC
authors.lastname: Aime
authors.affiliation: Institute of Plant Sciences, NAWI Graz, University of Graz, 8010 Graz, Austria.
authors.forename: Kevin
authors.initials: K
authors.lastname: Schneider
authors.affiliation: Institute of Plant Sciences, NAWI Graz, University of Graz, 8010 Graz, Austria.
authors.forename: Edith
authors.initials: E
authors.lastname: Stabentheiner
authors.affiliation: Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: Merje
authors.initials: M
authors.lastname: Toome-Heller
authors.affiliation: Department of Ecology, Swedish University of Agricultural Sciences, Post Office Box 7044, SE-75007 Uppsala, Sweden.
authors.forename: Göran
authors.initials: G
authors.lastname: Thor
authors.affiliation: Institute of Plant Sciences, NAWI Graz, University of Graz, 8010 Graz, Austria.
authors.forename: Helmut
authors.initials: H
authors.lastname: Mayrhofer
authors.affiliation: Department of Organismal Biology, Uppsala University, Norbyvägen 18D, 752 36 Uppsala, Sweden.
authors.forename: Hanna
authors.initials: H
authors.lastname: Johannesson
authors.affiliation: Division of Biological Sciences, University of Montana, Missoula, MT 59812, USA. Program in Integrated Microbial Biodiversity, Canadian Institute for Advanced Research, Toronto, Ontario, Canada.
authors.forename: John P
authors.initials: JP
authors.lastname: McCutcheon
mesh_terms: D001203:Ascomycota / Q000502:physiology*; D001487:Basidiomycota / Q000145:classification / Q000235:genetics / Q000502:physiology*; D008011:Lichens / Q000382:microbiology*; D010802:Phylogeny; D013559:Symbiosis