title: Isolation and characterization of the mating-type idiomorphs from the wheat septoria leaf blotch fungus Mycosphaerella graminicola.
abstract: Both mating-type loci from the wheat septoria leaf blotch pathogen Mycosphaerella graminicola have been cloned and sequenced. The MAT1-2 gene was identified by screening a genomic library from the MAT1-2 isolate IPO94269 with a heterologous probe from Tapesia yallundae. The MAT1-2 idiomorph is 2772 bp and contains a single gene encoding a putative high-mobility-group protein of 394 amino acids. The opposite idiomorph was obtained from isolate IPO323, which has the complementary mating type, by long-range PCR using primers derived from sequences flanking the MAT1-2 idiomorph. The MAT1-1 locus is 2839 bp in size and contains a single open reading frame encoding a putative alpha1-domain protein of 297 amino acids. Within the nonidiomorphic sequences, homology was found with palI, encoding a membrane receptor from Aspergillus nidulans, and a gene encoding a putative component of the anaphase-promoting complex from Schizosaccharomyces pombe and a DNA-(apurinic or apyrimidinic) lyase from S. pombe. For each of the MAT genes specific primers were designed and tested on an F1 mapping population that was generated from a cross between IPO323 and IPO94269. An absolute correlation was found between the amplified allele-specific fragments and the mating type as determined by backcrosses of each F1 progeny isolate to the parental isolates. The primers were also used to screen a collection of field isolates in a multiplex PCR. An equal distribution of MAT1-1 and MAT1-2 alleles was found for most geographic origins examined.
authors.affiliation: Plant Research International, Wageningen, 6700 AA, The Netherlands.
authors.forename: Cees
authors.initials: C
authors.lastname: Waalwijk
authors.forename: Odette
authors.initials: O
authors.lastname: Mendes
authors.forename: Els C P
authors.initials: EC
authors.lastname: Verstappen
authors.forename: Maarten A
authors.initials: MA
authors.lastname: de Waard
authors.forename: Gert H J
authors.initials: GH
authors.lastname: Kema
mesh_terms: D000595:Amino Acid Sequence; D003001:Cloning, Molecular; D017931:DNA Primers; D005656:Fungal Proteins / Q000235:genetics; D005658:Fungi / Q000235:genetics*; D005800:Genes, Fungal; D049770:Genes, Mating Type, Fungal; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D014908:Triticum / Q000382:microbiology*
chemical_list: D017931:DNA Primers; D005656:Fungal Proteins