scholarly journals Mapping of Avirulence Genes in the Rice Blast Fungus, Magnaporthe grisea, with RFLP and RAPD Markers

2000 ◽  
Vol 13 (2) ◽  
pp. 217-227 ◽  
Author(s):  
Waly Dioh ◽  
Didier Tharreau ◽  
Jean Loup Notteghem ◽  
Marc Orbach ◽  
Marc-Henri Lebrun
Keyword(s):  
Genetic Map ◽  
Rice Blast ◽  
Rapd Markers ◽  
Magnaporthe Grisea ◽  
Rice Blast Fungus ◽  
Single Copy ◽  
Avirulence Gene ◽  
Rflp Markers ◽  
Avirulence Genes ◽  
Blast Fungus

Three genetically independent avirulence genes, AVR1-Irat7, AVR1-MedNoï, and AVR1-Ku86, were identified in a cross involving isolates Guy11 and 2/0/3 of the rice blast fungus, Magnaporthe grisea. Using 76 random progeny, we constructed a partial genetic map with restriction fragment length polymorphism (RFLP) markers revealed by probes such as the repeated sequences MGL/MGR583 and Pot3/MGR586, cosmids from the M. grisea genetic map, and a telomere sequence oligonucleotide. Avirulence genes AVR1-MedNoï and AVR1-Ku86 were closely linked to te-lomere RFLPs such as marker TelG (6 cM from AVR1-MedNoï) and TelF (4.5 cM from AVR1-Ku86). Avirulence gene AVR1-Irat7 was linked to a cosmid RFLP located on chromosome 1 and mapped at 20 cM from the avirulence gene AVR1-CO39. Using bulked segregant analysis, we identified 11 random amplified polymorphic DNA (RAPD) markers closely linked (0 to 10 cM) to the avirulence genes segregating in this cross. Most of these RAPD markers corresponded to junction fragments between known or new transposons and a single-copy sequence. Such junctions or the whole sequences of single-copy RAPD markers were frequently absent in one parental isolate. Single-copy sequences from RAPD markers tightly linked to avirulence genes will be used for positional cloning.

Molecular mapping of two cultivar-specific avirulence genes in the rice blast fungus Magnaporthe grisea

2006 ◽  
Vol 277 (2) ◽  
pp. 139-148 ◽  
Author(s):  
Q. H. Chen ◽  
Y. C. Wang ◽  
A. N. Li ◽  
Z. G. Zhang ◽  
X. B. Zheng
Keyword(s):  
Rice Blast ◽  
Magnaporthe Grisea ◽  
Molecular Mapping ◽  
Rice Blast Fungus ◽  
Avirulence Genes ◽  
Blast Fungus

Relationship between Avirulence Genes of the Same Family in Rice Blast Fungus Magnaporthe grisea

2002 ◽  
Vol 68 (4) ◽  
pp. 300-306 ◽  
Author(s):  
Chao-Xi LUO ◽  
Hiromi HANAMURA ◽  
Hiroyo SEZAKI ◽  
Motoaki KUSABA ◽  
Hiroshi YAEGASHI
Keyword(s):  
Rice Blast ◽  
Magnaporthe Grisea ◽  
Rice Blast Fungus ◽  
Avirulence Genes ◽  
Blast Fungus

scholarly journals Physical Map and Organization of Chromosome 7 in the Rice Blast Fungus, Magnaporthe grisea

1999 ◽  
Vol 9 (8) ◽  
pp. 739-750 ◽  
Author(s):  
Heng Zhu ◽  
Barbara P. Blackmon ◽  
Maciek Sasinowski ◽  
Ralph A. Dean
Keyword(s):  
Rice Blast ◽  
Magnaporthe Grisea ◽  
Physical Map ◽  
Rice Blast Fungus ◽  
Chromosome 7 ◽  
Rflp Markers ◽  
Plant Interactions ◽  
Bac Clones ◽  
Blast Fungus ◽  
Biological Studies

The rice blast fungus Magnaporthe grisea is a highly destructive plant pathogen and one of the most important for studying various aspects of host-plant interactions. It has been widely adopted as a model organism because it is ideally suited for genetic and biological studies. To facilitate map-based cloning, chromosome walking, and genome organization studies of M. grisea, a complete physical map of chromosome 7 was constructed using a large-insert (130 kb) bacterial artificial chromosome (BAC) library. Using 147 chromosome 7-specific single-copy BAC clones and 20 RFLP markers on chromosome 7, 625 BAC clones were identified by hybridization. BAC clones were digested with HindIII, and fragments were size separated on analytical agarose gels to create DNA fingerprints. Hybridization contigs were constructed using a random cost algorithm, whereas fingerprinting contigs were constructed using the software package FPC. Results from both methods were generally in agreement, but numerous anomalies were observed. The combined data produced five robust anchored contigs after gap closure by chromosomal walking. The genetic and physical maps agreed closely. The final physical map was estimated to cover >95% of the 4.2 Mb of chromosome 7. Based on the contig maps, a minimum BAC tile containing 42 BAC clones was created, and organization of repetitive elements and expressed genes of the chromosome was investigated.

Transposition of MINE, a composite retrotransposon, in the avirulence gene ACE1 of the rice blast fungus Magnaporthe grisea

2005 ◽  
Vol 42 (9) ◽  
pp. 761-772 ◽  
Author(s):  
Isabelle Fudal ◽  
Heidi U. Böhnert ◽  
Didier Tharreau ◽  
Marc-Henri Lebrun
Keyword(s):  
Rice Blast ◽  
Magnaporthe Grisea ◽  
Rice Blast Fungus ◽  
Avirulence Gene ◽  
Blast Fungus

scholarly journals Transposon impala, a Novel Tool for Gene Tagging in the Rice Blast Fungus Magnaporthe grisea

2001 ◽  
Vol 14 (3) ◽  
pp. 308-315 ◽  
Author(s):  
François Villalba ◽  
Marc-Henri Lebrun ◽  
Aurélie Hua-Van ◽  
Marie-Josée Daboussi ◽  
Marie-Claire Grosjean-Cournoyer
Keyword(s):  
Nitrate Reductase ◽  
Fusarium Oxysporum ◽  
Rice Blast ◽  
Insertional Mutagenesis ◽  
Magnaporthe Grisea ◽  
Rice Blast Fungus ◽  
Single Copy ◽  
Wild Type ◽  
Type Locus ◽  
Blast Fungus

impala, a Tc1-mariner transposable element from Fusarium oxysporum, was introduced into the rice blast fungus Magnaporthe grisea to develop transposon-based insertional mutagenesis. A construct (pNIL160) containing an autonomous impala copy inserted in the promoter of niaD encoding Aspergillus nidulans nitrate reductase was introduced by transformation into a M. grisea nitrate reductase-deficient mutant. impala excision was monitored by restoration of prototrophy for nitrate. Southern analysis of niaD+ revertants revealed that impala was able to excise and reinsert at new loci in M. grisea. As observed for its host Fusarium oxysporum, impala inserted at a TA site left a typical excision footprint of 5 bp. We have shown that a defective impala copy was inactive in M. grisea, yet it can be activated by a functional impala transposase. A transformant carrying a single copy of pNIL160 was used to generate a collection of 350 revertants. Mutants either altered for their mycelial growth (Rev2) or nonpathogenic (Rev77) were obtained. Complementation of Rev77 with a 3-kb genomic fragment from a wild-type locus was successful, demonstrating the tagging of a pathogenicity gene by impala. This gene, called ORP1, is essential for penetration of host leaves by M. grisea and has no sequence homology to known genes.

Evidence of Parasexual Exchange of DNA in the Rice Blast Fungus Challenges Its Exclusive Clonality

1997 ◽  
Vol 87 (3) ◽  
pp. 284-294 ◽  
Author(s):  
R. S. Zeigler ◽  
R. P. Scott ◽  
H. Leung ◽  
A. A. Bordeos ◽  
J. Kumar ◽  
...  
Keyword(s):  
Rice Blast ◽  
Magnaporthe Grisea ◽  
Restriction Enzymes ◽  
Single Copy ◽  
The Philippines ◽  
Repetitive Elements ◽  
Blast Disease ◽  
Rflp Markers ◽  
Blast Fungus ◽  
Introgression Event

We applied DNA markers to determine whether parasexual recombination may contribute to the extreme genetic diversity and variability observed in Magnaporthe grisea, the causal agent of rice blast disease. Dispersed repetitive elements and mapped, low-copy restriction fragment length polymorphism (RFLP) probes were used to detect transfers of DNA between cultured isolates of M. grisea. Low-copy RFLP probes also were used to detect putative recombinants among isolates from well-characterized field populations of the pathogen. Microscopic examination of tufted mycelium between cocultured isolates revealed frequent hyphal fusions. Hyphal tips and conidia were recovered without selection from tufted zones in two separate vegetative pairings involving isolates with dissimilar haplotypes, based on the repetitive element MGR586. Haplotypic changes were observed at a higher frequency in tuft derivatives than in subcultures of each isolate alone. From 136 tuft derivatives analyzed, 5 putative recombinant haplotypes were identified. Introgression was demonstrated with two independent repetitive elements, fosbury and MGR586, as probes on DNA digested with several restriction enzymes. Introgressions were characterized by addition of 1 to 10 MGR586 bands, and 1 to 3 fosbury bands from one parent into the background of the other. Polymorphic single-copy probes were used to analyze putative recombinants. One probe detected an introgression event as predicted by analysis with MGR586. To assess the possible role of parasexual recombination in field populations of the pathogen, isolates in the Philippines previously grouped based on DNA fingerprinting were analyzed with low-copy RFLP markers. Polymorphism in single-copy loci typically was seen between, but not within, putative pathogen lineages. One lineage (designated lineage 4), however, was polymorphic for several probes. For some isolates, alleles at these loci comigrated with alleles characteristic of other lineages, suggesting the transfer of DNA fragments between lineages. One isolate was apparently a merodiploid, carrying an allele typical of lineage 4 plus another allele characteristic of a different lineage. In a survey of isolates from the Indian Himalayas, a merodiploid also was found with single- or low-copy probes. Examination of MGR586 profiles of the putative recombinant and its putative donor strains showed the expected introgression of MGR586 bands. The detection of parasexual DNA exchanges in wild-type strains under unselected conditions and the existence of merodiploids in nature suggest that parasexual recombination occurs in field populations of M. grisea. This raises questions concerning exclusive clonality in the blast fungus.

Synthesis and Biotransformation of Plausible Biosynthetic Intermediates of Salicylaldehyde-Type Phytotoxins of Rice Blast Fungus, Magnaporthe grisea

2011 ◽  
Vol 2011 (31) ◽  
pp. 6276-6280 ◽  
Author(s):  
Koji Tanaka ◽  
Ayaka Sasaki ◽  
Hai-Qun Cao ◽  
Teiko Yamada ◽  
Masahiro Igarashi ◽  
...  
Keyword(s):  
Rice Blast ◽  
Magnaporthe Grisea ◽  
Rice Blast Fungus ◽  
Blast Fungus
Sign in / Sign up

Export Citation Format

Share Document