title: Chromosome-based molecular characterization of pathogenic and non-pathogenic wheat isolates of Pyrenophora tritici-repentis.
abstract: The ToxA gene of Pyrenophora tritici-repentis encodes a host-selective toxin (Ptr ToxA) that has been shown to confer pathogenicity when used to transform a non-pathogenic wheat isolate. Major karyotype polymorphisms between pathogenic and non-pathogenic strains, and to a lesser extent among pathogenic strains, and among non-pathogenic strains were identified. ToxA was localized to a 3.0 Mb chromosome. PCR-based subtraction was carried out with the ToxA chromosome as tester DNA and genomic DNA from a non-pathogenic isolate as driver DNA. Seven of 8 single-copy probes that originated from the 3.0 Mb chromosome could be assigned to a 2.75 Mb chromosome of a non-pathogenic isolate. Nine different repetitive DNA probes originated from the 3.0 Mb chromosome, including sequences that correspond to known fungal transposable elements. Two additional single-copy probes that originated from a 3.4 Mb chromosome were unique to the pathogens and they correspond to a peptide synthetase gene. Our findings suggest substantial differences between pathogenic and non-pathogenic isolates of P. tritici-repentis.
authors.affiliation: Department of Botany and Plant Pathology, Oregon State University, 2082 Cordley Hall, Corvallis, OR 97331-2902, USA.
authors.forename: Amnon
authors.initials: A
authors.lastname: Lichter
authors.forename: Janey M
authors.initials: JM
authors.lastname: Gaventa
authors.forename: Lynda M
authors.initials: LM
authors.lastname: Ciuffetti
mesh_terms: D001203:Ascomycota / Q000235:genetics* / Q000302:isolation & purification; D015825:Chromosomes, Fungal; D015342:DNA Probes; D004271:DNA, Fungal / Q000032:analysis; D005656:Fungal Proteins; D007621:Karyotyping; D009183:Mycotoxins / Q000235:genetics*; D010453:Peptide Synthases / Q000235:genetics / Q000302:isolation & purification
chemical_list: D015342:DNA Probes; D004271:DNA, Fungal; D005656:Fungal Proteins; D009183:Mycotoxins; C105776:TOXA protein, Pyrenophora tritici-repentis; D010453:Peptide Synthases