title: Breeding systems in the lichen-forming fungal genus Cladonia.
abstract: The breeding systems of three species of the lichen-forming fungal genus Cladonia were investigated. Cladonia floerkeana, Cladonia galindezii, and Cladonia portentosa were selected due to their contrasting ecologies and reproductive strategies, and because they belong to the Lecanorales, the major lichen-forming order. Sibling single-spore progeny were collected from apothecia and used to establish axenic cultures. Two experimental approaches were used to determine breeding systems. First, RAPD-PCR and AFLP fingerprinting revealed that spores from the same apothecium were not genetically uniform, indicating heterothallism in each of these species. Second, segregation of a MAT-2 mating-type gene was assessed using degenerate PCR primers designed to amplify the high-mobility group region. A MAT-2 gene occurred in 40-60% of progeny, consistent with a heterothallic breeding system. The PCR product from C. galindezii was cloned and sequenced, and confirmed to have the characteristic motifs of a MAT-2 HMG gene. This is thought to be the first report of the use of segregation of a mating-type gene among ascospore progeny to determine the breeding system of a fungal species. The ecological significance of the results is discussed.
authors.affiliation: School of Biology, University Park, University of Nottingham, Nottingham NG7 2RD, UK.
authors.forename: Fabian A
authors.initials: FA
authors.lastname: Seymour
authors.forename: Peter D
authors.initials: PD
authors.lastname: Crittenden
authors.forename: Matthew J
authors.initials: MJ
authors.lastname: Dickinson
authors.forename: Mathieu
authors.initials: M
authors.lastname: Paoletti
authors.forename: Dolores
authors.initials: D
authors.lastname: Montiel
authors.forename: Lily
authors.initials: L
authors.lastname: Cho
authors.forename: Paul S
authors.initials: PS
authors.lastname: Dyer
mesh_terms: D000595:Amino Acid Sequence; D001203:Ascomycota / Q000235:genetics* / Q000502:physiology*; D016000:Cluster Analysis; D016172:DNA Fingerprinting; D004271:DNA, Fungal / Q000032:analysis / Q000737:chemistry / Q000235:genetics; D005800:Genes, Fungal; D049770:Genes, Mating Type, Fungal; D006609:High Mobility Group Proteins / Q000235:genetics; D008011:Lichens / Q000502:physiology; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D019105:Random Amplified Polymorphic DNA Technique; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D013172:Spores, Fungal / Q000235:genetics / Q000502:physiology
chemical_list: D004271:DNA, Fungal; D006609:High Mobility Group Proteins