Title: | Linkage of mating-type loci distinguishes bipolar from tetrapolar mating in basidiomycetous smut fungi |
Address: | "Biotechnology Laboratory, University of British Columbia, Vancouver, Canada" |
ISSN/ISBN: | 0027-8424 (Print) 1091-6490 (Electronic) 0027-8424 (Linking) |
Abstract: | "Sexual compatibility requires self vs. non-self recognition. Genetically, two compatibility or mating-type systems govern recognition in heterothallic basidiomycete fungi such as the edible and woodrotting mushrooms and the economically important rust and smut phytopathogens. A bipolar system is defined by a single genetic locus (MAT) that can have two or multiple alleles. A tetrapolar system has two loci, each with two or more specificities. We have employed two species from the genus Ustilago (smut fungi) to discover a molecular explanation for the genetic difference in mating systems. Ustilago maydis, a tetrapolar species, has two genetically unlinked loci that encode the distinct mating functions of cell fusion (a locus) and subsequent sexual development and pathogenicity (b locus). We have recently described a b locus in a bipolar species, Ustilago hordei, wherein the existence of an a locus has been suspected, but not demonstrated. We report here the cloning of an allele of the a locus (a1) from U. hordei and the discovery that physical linkage of the a and b loci in this bipolar fungus accounts for the distinct mating system. Linkage establishes a large complex MAT locus in U. hordei; this locus appears to be in a region suppressed for recombination" |
Keywords: | "Alleles Amino Acid Sequence Base Sequence Cloning, Molecular DNA, Fungal Fungal Proteins/*genetics *Genes, Fungal *Genes, Mating Type, Fungal *Genetic Linkage Genetic Variation Molecular Sequence Data Polymerase Chain Reaction Polymorphism, Restriction Fr;" |
Notes: | "MedlineBakkeren, G Kronstad, J W eng Research Support, Non-U.S. Gov't 1994/07/19 Proc Natl Acad Sci U S A. 1994 Jul 19; 91(15):7085-9. doi: 10.1073/pnas.91.15.7085" |