title: The a mating type locus of U. maydis specifies cell signaling components.
abstract: The a mating type locus of the phytopathogenic fungus U. maydis controls fusion of haploid cells and filamentous growth of the dikaryotic mycelium. The a locus exists in two alleles, termed a1 and a2, which are defined by nonhomologous DNA regions comprising 4.5 kb for a1 and 8 kb for a2, flanked by identical sequences. Based on functional assays, mutants, and sequencing, we demonstrate that the mating type in each allele is determined by a set of two genes. One encodes a precursor for a lipopeptide mating factor, and the other specifies the receptor for the pheromone secreted by cells of opposite mating type. Thus, U. maydis employs a novel strategy to determine its mating type by providing the primary determinants of cell-cell recognition directly from the mating type locus.
authors.affiliation: Institut für Genbiologische Forschung Berlin GmbH, Federal Republic of Germany.
authors.forename: M
authors.initials: M
authors.lastname: Bölker
authors.forename: M
authors.initials: M
authors.lastname: Urban
authors.forename: R
authors.initials: R
authors.lastname: Kahmann
mesh_terms: D000483:Alleles; D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D005800:Genes, Fungal / Q000235:genetics*; D049770:Genes, Mating Type, Fungal; D008969:Molecular Sequence Data; D010675:Pheromones / Q000235:genetics; D011956:Receptors, Cell Surface / Q000235:genetics; D016415:Sequence Alignment; D015398:Signal Transduction / Q000235:genetics*; D014588:Ustilago / Q000235:genetics*
chemical_list: D010675:Pheromones; D011956:Receptors, Cell Surface