Genome characterization of Pyrenophora tritici-repentis isolates reveals high plasticity and independent chromosomal location of ToxA and ToxB

被引:31
作者
Aboukhaddour, R. [1 ]
Cloutier, S. [2 ]
Ballance, G. M. [1 ]
Lamari, L. [1 ]
机构
[1] Univ Manitoba, Dept Plant Sci, Winnipeg, MB R3T 2N2, Canada
[2] Agr & Agri Food Canada, Cereal Res Ctr, Winnipeg, MB R3T 2M9, Canada
基金
加拿大自然科学与工程研究理事会;
关键词
RICE BLAST FUNGUS; TAN SPOT; GENETIC-ANALYSIS; ELECTROPHORETIC KARYOTYPE; LENGTH POLYMORPHISMS; VIRULENCE; WHEAT; IDENTIFICATION; DETOXIFICATION; INSENSITIVITY;
D O I
10.1111/j.1364-3703.2008.00520.x
中图分类号
Q94 [植物学];
学科分类号
071001 ;
摘要
The fungus Pyrenophora tritici-repentis (Died.) causes tan spot, an important leaf disease of wheat worldwide. Isolates of this pathogen have been collected and characterized into eight races on the basis of their ability to produce three different host-selective toxins. The karyotype of 47 isolates was determined by pulsed field gel electrophoresis. The collection originated from different parts of the world and included genotypes from all races. A single isolate was characterized for each of races 3, 4 and 6, whereas fourteen, five, nine, five and eleven isolates were karyotyped for races 1, 2, 5, 7 and 8, respectively. The survey showed that the chromosome number of P. tritici-repentis was highly variable, with some isolates having as few as eight chromosomes, but others having 11 or more. Similarly, the genome size ranged from 25.5 to 48.0 Mb, and individual chromosome sizes ranged from 1.3 to more than 5.7 Mb. Considerable variation was observed in karyotype patterns among the P. tritici-repentis isolates tested. A total of 29 different karyotypes was identified among the 47 isolates. These chromosome level variations were as variable for isolates within a race as for isolates across races. Southern blot analysis of the 47 isolates with ToxA and ToxB probes revealed that the toxin genes were always located on different chromosomes. Furthermore, with six chromosome-specific single-copy probes, the ToxA-carrying chromosome was shown to be homologous among the Ptr ToxA-producing isolates, with a related chromosome in the non-ToxA-producing isolates, suggesting that the chromosome on which ToxA generally resides is of an essential nature. Interestingly, a molecular rearrangement involving a translocation of ToxA to a different chromosome was identified in one isolate.
引用
收藏
页码:201 / 212
页数:12
相关论文
共 50 条
[1]   Genetic analysis of sensitivity to a Pyrenophora tritici-repentis necrosis-inducing toxin in durum and common wheat [J].
Anderson, JA ;
Effertz, RJ ;
Faris, JD ;
Francl, LJ ;
Meinhardt, SW ;
Gill, BS .
PHYTOPATHOLOGY, 1999, 89 (04) :293-297
[2]   Homologs of ToxB, a host-selective toxin gene from Pyrenophora tritici-repentis, are present in the genome of sister-species Pyrenophora bromi and other members of the Ascomycota [J].
Andrie, Rachael M. ;
Schoch, Conrad L. ;
Hedges, Rebecca ;
Spatafora, Joseph W. ;
Ciuffetti, Lynda M. .
FUNGAL GENETICS AND BIOLOGY, 2008, 45 (03) :363-377
[3]  
[Anonymous], 1989, Molecular Cloning: A Laboratory Manual
[4]  
Ballance G.M., 1996, MOL PLANT PATHOL ON
[5]   EFFECTS OF CROP-ROTATION AND RESIDUE MANAGEMENT-PRACTICES ON SEVERITY OF TAN SPOT OF WINTER-WHEAT [J].
BOCKUS, WW ;
CLAASSEN, MM .
PLANT DISEASE, 1992, 76 (06) :633-636
[6]  
Brasier CM., 1987, Evolutionary biology of the fungi, P231
[7]  
Burnett J., 2003, FUNGAL POPULATIONS S
[8]   A single gene encodes a selective toxin causal to the development of tan spot of wheat [J].
Ciuffetti, LM ;
Tuori, RP ;
Gaventa, JM .
PLANT CELL, 1997, 9 (02) :135-144
[9]   Chromosome evolution in eukaryotes: a multi-kingdom perspective [J].
Coghlan, A ;
Eichler, EE ;
Oliver, SG ;
Paterson, AH ;
Stein, L .
TRENDS IN GENETICS, 2005, 21 (12) :673-682
[10]  
Conners L.L., 1937, 17th Annu. Rep. Can. Plant Dis. Surv, P5