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cloning and analysis of cut1, a cutinase gene from magnaporthe grisea.a gene from magnaporthe grisea was cloned using a cdna clone of the colletotrichum gloeosporioides cutinase gene as a heterologous probe; the nucleotide sequence of a 2 kb dna segment containing the gene has been determined. dna hybridization analysis shows that the m. grisea genome contains only one copy of this gene. the predicted polypeptide contains 228 amino acids and is homologous to the three previously characterized cutinases, showing 74% amino acid similarity to the cutinase of c. gloeo ...19921557023
disruption of a magnaporthe grisea cutinase gene.using a one-step strategy to disrupt cut1, a gene for cutinase, cut1- mutants were generated in two strains of magnaporthe grisea. one strain, pathogenic on weeping lovegrass and barley and containing the arg3-12 mutation, was transformed with a disruption vector in which the aspergillus nidulans argb+ gene was inserted into cut1. prototrophic transformants were screened by southern hybridization, and 3 of 53 tested contained a disrupted cut1 gene (cut1::argb+). a second strain, pathogenic on ri ...19921557024
penetration of hard substrates by a fungus employing enormous turgor pressures.many fungal pathogens penetrate plant leaves from a specialized cell called an appressorium. the rice blast pathogen magnaporthe grisea can also penetrate synthetic surfaces such as poly(vinyl chloride). previous experiments have suggested that penetration requires an elevated appressorial turgor pressure. in the present report we have used nonbiodegradable mylar membranes, exhibiting a range of surface hardness, to test the proposition that penetration is driven by turgor. reducing appressorial ...19911837147
genetic mapping with dispersed repeated sequences in the rice blast fungus: mapping the smo locus.the smo genetic locus in strains of the fungus magnaporthe grisea that infect weeping lovegrass, directs the formation of correct cell shapes in asexual spores, infection structures, and asci. we have identified and characterized a smo- strain of m. grisea that infects rice. the smo mutation in this strain segregates as a single gene mutation and is allelic to previously identified smo alleles. a marked reduction in pathogenicity co-segregates with the smo- phenotype, suggesting that the smo loc ...19901980141
magnaporthe grisea genes for pathogenicity and virulence identified through a series of backcrosses.we have identified genes for pathogenicity toward rice (oryza sativa) and genes for virulence toward specific rice cultivars in the plant pathogenic fungus magnaporthe grisea. a genetic cross was conducted between the weeping lovegrass (eragrostis curvula) pathogen 4091-5-8, a highly fertile, hermaphroditic laboratory strain, and the rice pathogen o-135, a poorly fertile, female-sterile field isolate that infects weeping lovegrass as well as rice. a six-generation backcrossing scheme was then un ...19912016048
transformation of the rice blast fungus magnaporthe grisea to hygromycin b resistance.low frequency, integrative transformation of three fertile hermaphroditic strains of magnaporthe grisea has been achieved using plasmid pan7-1 and cosmid pan7-2, which contain an escherichia coli hygromycin b phosphotransferase gene linked to aspergillus nidulans regulatory sequences.19902357737
host species-specific conservation of a family of repeated dna sequences in the genome of a fungal plant pathogen.we have identified a family of dispersed repetitive dna sequences in the genome of magnaporthe grisea, the fungus that causes rice blast disease. we have named this family of dna sequences "mgr" for m. grisea repeat. analysis of five mgr clones demonstrates that mgr sequences are highly polymorphic. the segregation of mgr sequences in genetic crosses and hybridization of mgr probes to separated, chromosome-size dna molecules of m. grisea shows that this family of sequences is distributed among t ...19892602385
mg-sine: a short interspersed nuclear element from the rice blast fungus, magnaporthe grisea.a short interspersed nuclear element, mg-sine, was isolated and characterized from the genome of the rice blast fungus, magnaporthe grisea. mg-sine was isolated as an insertion element within pot2, an inverted-repeat transposon from m. grisea and shows typical features of a mammalian sine. mg-sine is present as a 0.47-kb interspersed sequence at approximately 100 copies per haploid genome in both rice and non-rice isolates of m. grisea, indicating a common evolutionary origin. secondary structur ...19957479950
genetic and physical mapping of telomeres in the rice blast fungus, magnaporthe grisea.telomeric restriction fragments were genetically mapped to a previously described linkage map of magnaporthe grisea, using rflps identified by a synthetic probe. (ttaggg)3. frequent rearrangement of telomeric sequences was observed in progeny isolates creating a potential for misinterpretation of data. therefore a consensus segregation data set used to minimize mapping errors. twelve of the 14 telomeres were found to be genetically linked to existing rflp markers. second-dimensional electrophore ...19957498730
a novel lipoxygenase from rice. primary structure and specific expression upon incompatible infection with rice blast fungus.a novel lipoxygenase cdna (3,007 base pairs) was isolated from rice leaves (oryza sativa cv. aichiasahi) which had been infected with an incompatible race of the rice blast fungus, magnaporthe grisea. a single copy of the gene is present in the rice genome and encodes a protein of 923 residues with a molecular weight of 102,714. this gene product shares the least amino acid sequence homology among plant lipoxygenases identified to date. a novel feature of this gene product is a putative transit ...19947508918
identification, cloning, and characterization of pwl2, a gene for host species specificity in the rice blast fungus.genetic analysis of host specificity in the rice blast fungus (magnaporthe grisea) identified a single gene, pwl2 (for pathogenicity toward weeping lovegrass), that exerts a major effect on the ability of this fungus to infect weeping lovegrass (eragrostis curvula). the allele of the pwl2 gene conferring nonpathogenicity was genetically unstable, with the frequent appearance of spontaneous pathogenic mutants. pwl2 was cloned based on its map position. large deletions detected in pathogenic mutan ...19957549480
comparison of fungi within the gaeumannomyces-phialophora complex by analysis of ribosomal dna sequences.four ascomycete species of the genus gaeumannomyces infect roots of monocotyledons. gaeumannomyces graminis contains four varieties, var. tritici, var. avenae, var. graminis, and var. maydis. g. graminis varieties tritici, avenae, and graminis have phialophora-like anamorphs and, together with the other gaeumannomyces and phialophora species found on cereal roots, constitute the gaeumannomyces-phialophora complex. relatedness of a number of gaeumannomyces and phialophora isolates was assessed by ...19957574606
grasshopper, a long terminal repeat (ltr) retroelement in the phytopathogenic fungus magnaporthe grisea.the fungal phytopathogen magnaporthe grisea parasitizes a wide variety of gramineous hosts. in the course of investigating the genetic relationship between pathogen genotype and host specificity we identified a retroelement that is present in some strains of m. grisea that infect finger millet and goosegrass (members of the plant genus eleusine). the element, designated grasshopper (grh), is present in multiple copies and dispersed throughout the genome. dna sequence analysis showed that grassho ...19937679935
having a blast: exploring the pathogenicity of magnaporthe grisea.the rice blast fungus magnaporthe grisea has an exquisite level of pathogenic specialization, allowing it to infect and colonize rice, subvert the metabolism of the host and spread to new hosts. through a combination of cytology and molecular-genetic analysis, a picture is gradually emerging of the many interlinked processes that are required for successful infection of the plant.19957719639
host species-specific repetitive dna sequence in the genome of magnaporthe grisea, the rice blast fungus.we cloned a repetitive sequence to show rflps in the genome of magnaporthe grisea, a fungal pathogen responsible for rice blast. as the sequence was 0.8 kb in length and dispersed in the genome, it was named mgsr1 (for magnaporthe grisea short repeat 1). mgsr1 was conserved highly in the genome of rice pathogens, but poorly in the genome of pathogens of grasses other than rice. and the rflps, displayed with the sequence, could distinguish between clonal lineages in rice-pathogenic isolates. the ...19937765312
pot2, an inverted repeat transposon from the rice blast fungus magnaporthe grisea.we report the cloning and characterisation of pot2, a putative transposable element from magnaporthe grisea. the element is 1857 bp in size, has 43-bp perfect terminal inverted repeats (tirs) and 16-bp direct repeats within the tirs. a large open reading frame, potentially coding for a transposase-like protein, was identified. this putative protein coding region showed extensive identity to that of fot1, a transposable element from another phytopathogenic fungus, fusarium oxysporum. pot2, like t ...19947816044
isolation of the mating-type genes of the phytopathogenic fungus magnaporthe grisea using genomic subtraction.using genomic subtraction, we isolated the mating-type genes (mat1-1 and mat1-2) of the rice blast fungus, magnaporthe grisea. transformation of m. grisea strains of one mating type with a linearized cosmid clone carrying the opposite mating-type gene resulted in many "dual maters," strains that contain both mating-type genes and successfully mate with mat1-1 and mat1-2 testers. dual maters differed in the frequency of production of perithecia in pure culture. ascospores isolated from these homo ...19947828813
crystal structure of scytalone dehydratase--a disease determinant of the rice pathogen, magnaporthe grisea.rice blast is caused by the pathogenic fungus,-magnaporthe grisea. non-pathogenic mutants have been identified that lack enzymes in the biosynthetic pathway of dihydroxynapthalene-derived melanin. these enzymes are therefore prime targets for fungicides designed to control rice blast disease. one of the enzymes identified by genetic analysis as a disease determinant is scytalone dehydratase.19947866745
isolation of a monocot 3-hydroxy-3-methylglutaryl coenzyme a reductase gene that is elicitor-inducible.the rice (oryza sativa) phytoalexins, momilactones and oryzalexins, are synthesized by the isoprenoid pathway. an early step in this pathway, one that is rate-limiting in mammalian systems, is catalyzed by the enzyme 3-hydroxy-3-methylglutaryl coenzyme a reductase (hmgr). a gene that encodes this enzyme has been isolated from rice, and found to contain an open reading frame of 1527 bases. the encoded protein sequence of the rice hmgr appears to be conserved with respect to other hmgr proteins, a ...19948049366
isolation of the erg2 gene, encoding sterol delta 8-->delta 7 isomerase, from the rice blast fungus magnaporthe grisea and its expression in the maize smut pathogen ustilago maydis.the magnaporthe grisea erg2 gene, encoding delta 8-->delta 7 sterol isomerase, was isolated from a genomic library by heterologous hybridization to a fragment of the ustilago maydis erg2 gene. the isolated gene contained a reading frame of 745 bp which encoded a protein of 221 amino acids. the coding region was interrupted by a single putative 79-bp-long intron. the deduced amino-acid sequence exhibited similarity to the erg2 gene products of u. maydis and of saccharomyces cerevisiae, particular ...19948082205
polyhydroxynaphthalene reductase involved in melanin biosynthesis in magnaporthe grisea. purification, cdna cloning and sequencing.during the biosynthesis of fungal melanin, tetrahydroxynaphthalene reductase catalyzes the nadph-dependent reduction of 1,3,6,8-tetrahydroxynaphthalene (t4hn) into (+)-scytalone and 1,3,8-trihydroxynaphthalene into (-)-vermelone. the enzyme from magnaporthe grisea, the fungus responsible for rice blast disease, has been purified to homogeneity. it is a tetramer of four identical 30-kda subunits. a full-length cdna clone of about 1 kb encoding t4hn reductase has been isolated from a cdna library ...19948112349
the ebb and flow of a fungal genome.transposable dna elements have only recently been described in a few species of filamentous fungi, but may be more abundant than previously believed. several different elements have been isolated from the rice blast pathogen magnaporthe grisea. the distribution and amplification of these elements suggest a potential role in the evolution of the fungal genome.19938162425
identification and characterization of mpg1, a gene involved in pathogenicity from the rice blast fungus magnaporthe grisea.differential cdna cloning was used to identify genes expressed during infectious growth of the fungal pathogen magnaporthe grisea in its host, the rice plant. we characterized one of these genes, mpg1, in detail. using a novel assay to determine the proportion of fungal biomass present in the plant, we determined that the mpg1 transcript was 60-fold more abundant during growth in the plant than in culture. mpg1 mutants have a reduced ability to cause disease symptoms that appears to result from ...19938312740
preliminary crystallographic studies on scytalone dehydratase from magnaporthe grisea.magnaporthe grisea are pathogenic, directly penetrating fungi which cause rice blast disease. isolated, non-pathogenic mutant strains which are defective in the biosynthesis of dihydroxynapthalene-derived melanin fail to infect host plants and have been shown to lack certain key enzymes in melanin biosynthesis. one such enzyme is scytalone dehydratase that converts scytalone to 1,3,8-trihydroxy-naphthalene. crystallization trials of scytalone dehydratase were undertaken with the expectation that ...19938355286
the camp-dependent protein kinase catalytic subunit is required for appressorium formation and pathogenesis by the rice blast pathogen magnaporthe grisea.magnaporthe grisea, the causal agent of rice blast disease, differentiates a specialized infection cell, an appressorium, that is required for infection of its host. previously, camp was implicated in the endogenous signaling pathway leading to appressorium formation. to obtain direct evidence for the role of camp in appressorium formation, the gene encoding the catalytic subunit of the camp-dependent protein kinase (cpka) was cloned, sequenced, and disrupted. polymerase chain reaction primers d ...19958535140
detection of additional restriction fragment length polymorphisms among the weakly virulent (nonaggressive) and highly virulent (aggressive) isolates of leptosphaeria maculans.isolates of leptosphaeria maculans were analyzed for their genetic relatedness based on dna restriction fragment length polymorphisms (rflps), employing as southern hybridization probes a combination of heat shock responsive genes (hsp70 and hsp80 from neurospora crassa), the cutinase gene of magnaporthe grisea, and cloned genomic dna sequences from a virulent strain. southern hybridization analysis revealed a high frequency of dna polymorphism. restriction fragments generated by each enzyme-pro ...19958542555
purification, cloning and characterization of two xylanases from magnaporthe grisea, the rice blast fungus.magnaporthe grisea, the fungal pathogen that causes rice blast disease, secretes two endo-beta-1,4-d-xylanases (e. c. 3.2.1.8) when grown on rice cell walls as the only carbon source. one of the xylanases, xyn33, is a 33-kd protein on sodium dodecyl sulfate-polyacrylamide gel and accounts for approximately 70% of the endoxylanase activity in the culture filtrate. the second xylanase, xyn22, is a 22-kd protein and accounts for approximately 30% of the xylanase activity. the two proteins were puri ...19958589407
genetic differentiation in the rice blast fungus revealed by the distribution of the fosbury retrotransposon.repetitive dna sequences genetically differentiate certain host-specific forms of the plant pathogenic fungus pyricularia grisea. for example, high copy numbers of a sequence designated mgr586 are conserved in isolates that infect rice. in this report, we describe the molecular characterization of another repetitive dna sequence designated fosbury. restriction mapping and dna sequence analysis show that fosbury is a member of a long terminalrepeat (ltr)-containing retrotransposon family, and gel ...19968634946
the pwl host specificity gene family in the blast fungus magnaporthe grisea.the pwl2 gene, isolated from a magnaporthe grisea rice pathogen, prevents this fungus from infecting a second host grass, weeping lovegrass. we have investigated the distribution of sequences homologous to pwl2 in m. grisea strains isolated from diverse grass species. multiple pwl2 homologs with varying degrees of sequence homology were identified. the presence of pwl2 homologs does not correlate with an avirulent phenotype on weeping lovegrass in many cases: some strains were fully pathogenic o ...19958664503
cloning and characterization of a melanin biosynthetic thr1 reductase gene essential for appressorial penetration of colletotrichum lagenarium.melanin biosynthesis of colletotrichum lagenarium is essential for appressorial penetration of the host plant. a melanin deficient mutant 9141 (thr-) has a defect in the conversion of 1,3,8-trihydroxynaphthalene to vermelone in the melanin biosynthetic pathway. the mutant formed nonmelanized appressoria and had little infectivity on cucumber leaves. a cosmid clone pcr1 was selected from a cosmid library of wild-type c. lagenarium by means of a heterologous probe brm2, one of the clustered genes ...19968672814
rearrangements at a dna-fingerprint locus in the rice blast fungus.populations of the rice blast fungus, magnaporthe grisea, can be sorted into clonal lineages based on restriction fragment length polymorphisms (rflps) detected with the repetitive dna sequence mgr586. mechanisms that produce dna-fingerprint variation among lineages, are not known. in the process of analyzing the meiotic segregation of mgr586 rflps we identified a novel polymorphism, called mgr586-p2, in one member of a sister-spore pair from a complete tetrad. molecular cloning revealed that p2 ...19968753657
mpg1, a gene encoding a fungal hydrophobin of magnaporthe grisea, is involved in surface recognition.upon encountering a leaf surface, emergent germ tubes from conidia of the rice blast fungus, magnaporthe grisea, form infection structures called appressoria that allow direct penetration of plant cells. the mpg1 gene encodes a fungal hydrophobin of m. grisea that is expressed during development of aerial hyphae, conidia, and appressoria. deletion of mpg1 reduces the efficiency of appressorium formation. we found that yeast extract repressed mpg1 expression in vitro and inhibited appressorium de ...19968755621
nut1, a major nitrogen regulatory gene in magnaporthe grisea, is dispensable for pathogenicity.nut1, a gene homologous to the major nitrogen regulatory genes nit-2 of neurospora crassa and area of aspergillus nidulans, was isolated from the rice blast fungus, magnaporthe grisea. nut1 encodes a protein of 956 amino acid residues and, like nit-2 and area, has a single putative zinc finger dna-binding domain. functional equivalence of nut1 to area was demonstrated by introducing the nut1 gene by dna-mediated transformation into an area loss-of-function mutant of a. nidulans. the introduced n ...19968757395
maggy, a retrotransposon in the genome of the rice blast fungus magnaporthe grisea.full-length copies of a previously described repetitive dna sequence (ch2-8) were isolated from the genome of the magnaporthe grisea strain 2539. one copy of the complete element was sequenced and found to resemble a gypsy-like ltr retrotransposon. we named this element maggy (magnaporthe gypsy-like element). maggy contains two internal orfs putatively encoding gag, pol and env-like proteins which are similar to peptides encoded by retroelements identified in other filamentous fungi. maggy was f ...19968757397
the magnaporthe grisea dna fingerprinting probe mgr586 contains the 3' end of an inverted repeat transposon.the magnaporthe grisea repeat (mgr) sequence mgr586 has been widely used for population studies of the rice blast fungus, and has enabled classification of the fungal population into hundreds of genetic lineages. while studying the distribution of mgr586 sequences in strains of m. grisea, we discovered that the plasmid probe pcb586 contains a significant amount of single-copy dna. to define precisely the boundary of the repetitive dna in pcb586, this plasmid and four cosmid clones containing mgr ...19968757398
crystallization and preliminary x-ray diffraction study of 1 ,3,8-trihydroxynaphthalene reductase from magnaporthe grisea.1,3,8-trihydroxynaphthalene reductase was crystallized in the presence of nadph and the inhibitor tricyclazole. the crystals are trigonal, space group p3(1)21 or its enantiomorph p3(2)21. two crystal forms with slightly different cell dimensions were obtained. form a has unit cell dimensions a = b = 142.6 angstrom, c = 70.1 angstrom and form b cell dimensions a = b = 142.6 angstrom, c = 72.9 angstrom. the diffraction pattern of the latter crystal form extends to 2.5 angstrom resolution.19968860003
breaking and entering: host penetration by the fungal rice blast pathogen magnaporthe grisea.fungal plant pathogens have evolved diverse mechanisms for penetrating into host plant tissue, ranging from entry through natural plant openings to various mechanisms of direct penetration through the outer surface. the filamentous fungus magnaporthe grisea can cause disease on many species of the grass (poaceae) family. the disease on rice, rice blast, is of enormous economic importance and biological interest. the mechanism used by this pathogen for breaching the formidable host surface barrie ...19968905089
new cosmid vectors for library construction, chromosome walking and restriction mapping in filamentous fungi.new cosmid vectors were constructed for the ascomycete fungus, magnaporthe grisea and the basidiomycete fungus, ustilago maydis. these vectors are capable of transforming m. grisea at frequencies of up to 5 transformants/micrograms linear dna and u. maydis at up to 25 transformants/microgram circular dna for integrative transformation. in addition, 2800 transformants/microgram dna are possible when using an autonomously replicating vector. since the promoters used in these vectors function in ot ...19968918238
transposon-like sequences at the tox2 locus of the plant-pathogenic fungus cochliobolus carbonum.the ascomycete fungus cochliobolus carbonum race 1 is pathogenic on certain genotypes of maize due to the production of hc-toxin, a host-specific cyclic peptide. hc-toxin production is controlled, at least in part, by a duplicated 22-kb region of dna that is found only in toxin-producing isolates of the fungus. this 22-kb region of dna is flanked by a repetitive element. we have sequenced the element and found an interrupted reading frame that would encode a product similar to transposases from ...19968918240
crystal structure of the ternary complex of 1,3,8-trihydroxynaphthalene reductase from magnaporthe grisea with nadph and an active-site inhibitor.the enzyme 1,3,8-trihydroxynaphthalene reductase (thnr) catalyzes an essential reaction in the biosynthesis of melanin, a black pigment crucial for the pathogenesis of the rice blast fungus, magnaporthe grisea. the enzyme is the biochemical target of several commercially important fungicides which are used to prevent blast disease in rice plants. we have determined the structure of the ternary complex of thnr with bound nadph and a fungicide, tricyclazole.19968939741
map kinase and camp signaling regulate infection structure formation and pathogenic growth in the rice blast fungus magnaporthe grisea.many fungal pathogens invade plants using specialized infection structures called appressoria that differentiate from the tips of fungal hyphae contacting the plant surface. we demonstrate a role for a map kinase that is essential for appressorium formation and infectious growth in magnaporthe grisea, the fungal pathogen responsible for rice blast disease. the pmk1 gene of m. grisea is homologous to the saccharomyces cerevisiae map kinases fus3/kss1, and a gst-pmk1 fusion protein has kinase acti ...19968946911
cloning and structural analysis of the melanin biosynthesis gene scd1 encoding scytalone dehydratase in colletotrichum lagenarium.appressoria of the phytopathogenic fungus colletotrichum lagenarium contain melanin, which has been implicated as an important factor in the penetration of host plants. a cdna clone containing the melanin biosynthetic gene encoding scytalone dehydratase (scd1) from c. lagenarium was identified by hybridization with a heterologous cdna probe from magnaporthe grisea. the cdna clone was used to identify a cosmid containing scd1 in a genomic library of c. lagenarium, and the nucleotide sequence was ...19968953707
a flexible lid controls access to the active site in 1,3,8-trihydroxynaphthalene reductase.the crystal structures of apo-1,3,8-trihydroxynaphthalene reductase from magnaporthe grisea and a binary complex of the enzyme with nadph have been determined to 2.8 a resolution. in both cases, the overall structure is preserved compared to the structure of the ternary complex of the enzyme with nadph and an active site inhibitor. no electron density for the helix-loop-helix region comprising residues 214-244 is observed indicating structural disorder in this part of the apoenzyme and the binar ...19979001392
the transposable element tan1 of aspergillus niger var. awamori, a new member of the fot1 family.aspergillus niger var. awamori has transposable elements that we refer to as vader and tan1 (transposon a. niger). vader was identified by screening unstable nitrate reductase (niad) mutants for insertions. four of the isolated niad mutants were shown to contain a small insertion element. this 437 bp insertion element, vader, is flanked by 44 bp inverted repeats (ir) and is present in approximately 15 copies in the genomes of two a. niger strains examined. a synthetic 44 bp oligomer of the inver ...19969003286
construction and characterization of a magnaporthe grisea bacterial artificial chromosome librarydiaz-perez, s. v., crouch, v. w., and orbach, m. j. 1996. construction and characterization of a magnaporthe grisea bacterial artificial chromosome library. fungal genet. biol. 20, 280-288. a bacterial artificial chromosome (bac) library of magnaporthe grisea containing 4128 clones with an average insert size of 66-kb has been constructed. this library represents seven genome equivalents of m. grisea and has been demonstrated to be representative of the genome by screening for the presence of se ...19969045758
trihydroxynaphthalene reductase from magnaporthe grisea: realization of an active center inhibitor and elucidation of the kinetic mechanism.active trihydroxynaphthalene reductase (3hnr) is essential for the biosynthesis of fungal melanin by magnaporthe grisea and is a focus of inhibitor design studies directed toward control of blast disease in rice. tricyclazole, a preventative fungicide against rice blast, has been previously characterized as inhibiting 3hnr noncompetitively [viviani, f., vors, j. p., gaudry, m., & marquet, a. (1993) bull. soc. chem. fr. 136, 395-404] with respect to its naphthol substrate. our steady-state kineti ...19979048570
analysis of host-induced response in the rice blast fungus magnaporthe grisea using two-dimensional polyacrylamide gel electrophoresis.two-dimensional (2-d) polyacrylamide gel electrophoresis of proteins was used to study the response of the rice blast fungus to extracts prepared from resistant and susceptible rice cultivars. a protein of molecular mass 31 kda was induced by a susceptible host extract, while the fungus exposed to extract from the resistant cultivar and the untreated samples did not show the presence of this protein. levels of this 31 kda protein increased 30-fold, 72 h after treatment with plant extracts, with ...19979059839
cross-pathway and pathway-specific control of amino acid biosynthesis in magnaporthe griseathe gene encoding the small subunit of the arginine-specific carbamoyl phosphate synthetase, arg2, of magnaporthe grisea was characterized to examine the basic regulation of biosynthetic genes in this plant pathogen. the transcript of the arg2 gene contains an upstream open reading frame (uorf) that is similar to uorfs found in the homologous genes of neurospora crassa (arg-2) and saccharomyces cerevisiae (cpa1), suggesting that the m. grisea gene is translationally regulated by a mechanism that ...19979073479
inheritance of dsrnas in the rice blast fungus, magnaporthe grisea.the 1.6 and 1.8 kbp dsrnas have been found in the rice blast fungus, magnaporthe grisea strain mg01. these dsrna molecules are located in cytoplasm of the fungal cells and maintained stably during vegetative growth. three crosses between dsrna free and dsrna containing strains including a parental cross, sib-mating and back cross were made to follow the inheritance of dsrnas during sexual reproduction. approximately 10% of ascospore progenies (11 out of 105) contained dsrnas from all three cross ...19979084143
organisation and molecular analysis of repeated dna sequences in the rice blast fungus magnaporthe grisea.the distribution of a previously described repeated dna sequence present as a 1.3-kb psti fragment in the genome of the rice blast fungus magnaporthe grisea was analysed by carrying out dna fingerprint analysis of 36 isolates including rice, non-rice and laboratory strains. the analysis of various higher-molecular-weight psti fragments with homology to the 1.3-kb repeat revealed that these may arise predominantly from transposon insertions or point mutations. analysis of a 5.1-kb derivative reve ...19979108145
cross-pathway and pathway-specific control of amino acid biosynthesis in magnaporthe grisea.the gene encoding the small subunit of the arginine-specific carbamoyl phosphate synthetase, arg2, of magnaporthe grisea was characterized to examine the basic regulation of biosynthetic genes in this plant pathogen. the transcript of the arg2 gene contains an upstream open reading frame (uorf) that is similar to uorfs found in the homologous genes of neurospora crassa (arg-2) and saccharomyces cerevisiae (cpa1), suggesting that the m. grisea gene is translationally regulated by a mechanism that ...19979126616
characterization and overexpression of the aspergillus niger gene encoding the camp-dependent protein kinase catalytic subunit.the gene pkac encoding the catalytic subunit of camp-dependent protein kinase has been isolated from the industrially important filamentous fungus aspergillus niger. a probe for screening a. niger phage libraries was generated by a polymerase chain reaction using degenerate primers. cdna and genomic dna clones were isolated and sequenced. an open reading frame of 1440 bp, interrupted by three short introns, encodes a polypeptide of 480 amino acids with a calculated molecular mass of 53813 da. th ...19979141684
inhibition of pathogenicity of the rice blast fungus by saccharomyces cerevisiae alpha-factor.magnaporthe grisea is a fungal pathogen with two mating types, mat1-1 and mat1-2, that forms a specialized cell necessary for pathogenesis, the appressorium. saccharomyces cerevisiae alpha-factor pheromone blocked appressorium formation in a mating type-specific manner and protected plants from infection by mat1-2 strains. experiments with alpha-factor analogs suggest that the observed activity is due to a specific interaction of alpha-factor with an m. grisea receptor. culture filtrates of a ma ...19979148806
the melanin biosynthesis genes of alternaria alternata can restore pathogenicity of the melanin-deficient mutants of magnaporthe grisea.the phytopathogenic fungi magnaporthe grisea and alternaria alternata produce melanin via the polyketide biosynthesis, and both fungi form melanized colonies. however, the site of melanin deposition and the role of melanin in pathogenicity differ between these two fungi. m. grisea accumulates melanin in appressoria, and their melanization is essential for host penetration. on the other hand, a. alternata produces colorless appressoria, and melanin is not relevant to host penetration. we examined ...19979150594
molecular cloning and sequence analysis of a putative ras gene of the phytopathogenic fungus botryotinia fuckeliana.we solated and determined the complete nucleotide sequence of a ras gene from botryotinia fuckeliana, the causal agent of gray mold disease. furthermore, in two other phytopathogenic fungi, magnaporthe grisea (rice blast fungus) and colletotrichum lagenarium (an anthracnose fungus), ras gene homologs were identified by amplifying gene fragments in polymerase chain reactions. the putative ras gene of b. fuckeliana encoded a polypeptide of 212 amino acids, and the coding sequence was interrupted b ...19979163749
flipper, a mobile fot1-like transposable element in botrytis cinerea.a transposable element, flipper, was isolated from the phytopathogenic fungus botrytis cinerea. the element was identified as an insertion sequence within the coding region of the nitrate reductase gene. the flipper sequence is 1842 bp long with perfect inverted terminal repeats (itrs) of 48 bp and an open reading frame (orf) of 533 amino acids, potentially encoding for a transposase; the element is flanked by the dinucleotide ta. the encoded protein is very similar to the putative transposases ...19979202383
purification and antifungal activity of a basic 34 kda beta-1,3-glucanase from soybean hypocotyls inoculated with phytophthora sojae f. sp. glycines.inoculation of soybean (glycine max l. cv. jangyup) hypocotyls with phytophthora sojae f. sp. glycines results in a marked accumulation of some pathogenesis-related (pr) proteins. a basic beta-1,3-glucanase (34 kda) was purified from soybean hypocotyls infected by an incompatible race of p. sojae f. sp. glycines using cm-cellulose cation exchange chromatography and bio-gel p-60 gel filtration. the purified soybean beta-1,3-glucanase cross-reacted with polyclonal antibody raised against a tomato ...19979264030
a large-insert (130 kbp) bacterial artificial chromosome library of the rice blast fungus magnaporthe grisea: genome analysis, contig assembly, and gene cloning.magnaporthe grisea (hebert) barr causes rice blast, one of the most devastating diseases of rice (oryza sativa) worldwide. this fungus is an ideal organism for studying a number of aspects of plant-pathogen interactions, including infection-related morphogenesis, avirulence, and pathogen evolution. to facilitate m. grisea genome analysis, physical mapping, and positional cloning, we have constructed a bacterial artificial chromosome (bac) library from the rice infecting strain 70-15. a new metho ...19979290247
aspergillus fumigatus arp1 modulates conidial pigmentation and complement deposition.aspergillus fumigatus is an important pathogen causing invasive pulmonary aspergillosis in immunocompromised patients. the fungus propagates by conidia, which are the infectious structures inhaled by the human host. opsonophagocytosis is thought to contribute to clearance of the inhaled conidia, a process that is facilitated by complement deposition on conidial surfaces. we now show that conidial colour mutants exhibit significant increases in c3 binding capacity compared with wild type. a reddi ...19979383199
g protein alpha subunit genes control growth, development, and pathogenicity of magnaporthe grisea.three g protein alpha subunit genes have been cloned and characterized from magnaporthe grisea: maga is very similar to cpg-2 of cryphonectria parasitica; magb is virtually identical to cpg-1 of cryphonectria parasitica, to gna1 of neurospora crassa, and to fada of emericella nidulans; and magc is most similar to gna2 of neurospora crassa. homologous recombination resulting in targeted deletion of maga had no effect on vegetative growth, conidiation, or appressorium formation. deletion of magc r ...19979390422
rapd-based screening of genomic libraries for positional cloning.rapd markers are frequently used for positional cloning. however, rapd markers often contain repeated sequences which prevent genomic library screening by hybridisation. we have developed a simple rapd analysis of genomic libraries based on the identification of cosmid pools and clones amplifying the rapd marker of interest. our method does not require the cloning or characterisation of the rapd marker as it relies on the analysis of cosmid pools or clones using a simple rapd protocol. we applie ...19979396827
the adenylate cyclase gene mac1 of magnaporthe grisea controls appressorium formation and other aspects of growth and development.magnaporthe grisea, the causal agent of rice blast disease, differentiates a specialized infection structure called an appressorium that is crucial for host plant penetration. previously, it was found that camp regulates appressorium formation. to further understand the cellular mechanisms involved in appressorium formation, we have cloned a gene (mac1) encoding adenylate cyclase, a membrane-bound enzyme that catalyzes the production of camp from atp, by using a polymerase chain reaction-based s ...19979401122
mutants of the phytopathogenic fungus magnaporthe grisea deficient in alternative, cyanide-resistant, respirationthe phytopathogenic fungus magnaporthe grisea has a cyanide-resistant respiratory pathway. the fungicide ssf-126 ((e)-2-methoxyimino-n-methyl-2-(2-phenoxyphenyl) acetamide) blocks the cytochrome electron transport of m. grisea and induces the alternative respiratory pathway. twelve mutants of m. grisea more susceptible to ssf-126 than wild type were identified after n-methyl-n'-nitro-n-nitrosoguanidine mutagenesis. five mutants retained a reduced alternative respiration activity, and seven mutan ...19979454649
interactions between spore morphogenetic mutations affect cell types, sporulation, and pathogenesis in magnaporthe grisea.we have previously defined four single-gene mutations, con1, con2, con4, and con7, that control various stages of spore morphogenesis in the rice blast fungus. to delineate the developmental pathway of spore morphogenesis, we investigated the interactions among these morphogenetic genes by generating strains with double mutations via transformation-mediated gene disruption. plasmids containing portions of the inactivated con4 and con7 genes were introduced into strains harboring single mutation ...19989487695
glisoprenins c, d and e, new inhibitors of appressorium formation in magnaporthe grisea, from cultures of gliocladium roseum. 1. production and biological activities.glisoprenins c, d, and e, new glisoprenin derivatives, were isolated together with glisoprenin a from submerged cultures of the deuteromycete gliocladium roseum ha190-95. all glisoprenins inhibited appressorium formation in magnaporthe grisea on inductive (hydrophobic) surfaces. the compounds exhibited moderate cytotoxic, but no antifungal, antibacterial or phytotoxic activities.19989544931
glisoprenins c, d and e, new inhibitors of appressorium formation in magnaporthe grisea, from cultures of gliocladium roseum. 2. structure determination. 19989544946
magnaporthe grisea pathogenicity genes obtained through insertional mutagenesis.we have initiated a mutational analysis of pathogenicity in the rice blast fungus, magnaporthe grisea, in which hygromycin-resistant transformants, most generated by restriction enzyme-mediated integration (remi), were screened for the ability to infect plants. a rapid primary infection assay facilitated screening of 5,538 transformants. twenty-seven mutants were obtained that showed a reproducible pathogenicity defect, and 18 of these contained mutations that cosegregated with the hygromycin re ...19989574508
identification of three ubiquitin genes of the rice blast fungus magnaporthe grisea, one of which is highly expressed during initial stages of plant colonisation.differential cdna screening was used to identify genes expressed during the colonisation of rice leaves by the pathogenic fungus magnaporthe grisea. this led to the identification of a gene, called uep1, which encodes a ubiquitin extension protein. uep1 was highly expressed 48 h after initial fungal infection of rice leaves when m. grisea is proliferating in the leaf epidermis but not yet causing disease symptoms. uep1 appeared to be down-regulated after this time despite further extensive growt ...19989618586
complementation of the mpg1 mutant phenotype in magnaporthe grisea reveals functional relationships between fungal hydrophobins.the functional relationship between fungal hydrophobins was studied by complementation analysis of an mpg1(-) gene disruption mutant in magnaporthe grisea. mpg1 encodes a hydrophobin required for full pathogenicity of the fungus, efficient elaboration of its infection structures and conidial rodlet protein production. seven heterologous hydrophobin genes were selected which play distinct roles in conidiogenesis, fruit body development, aerial hyphae formation and infection structure elaboration ...19989670001
divergent camp signaling pathways regulate growth and pathogenesis in the rice blast fungus magnaporthe grisea.camp is involved in signaling appressorium formation in the rice blast fungus magnaporthe grisea. however, null mutations in a protein kinase a (pka) catalytic subunit gene, cpka, do not block appressorium formation, and mutations in the adenylate cyclase gene have pleiotropic effects on growth, conidiation, sexual development, and appressorium formation. thus, camp signaling plays roles in both growth and morphogenesis as well as in appressorium formation. to clarify camp signaling in m. grisea ...19989707535
identification of four chitin synthase genes in the rice blast disease agent magnaporthe grisea.four chitin synthase gene fragments were isolated from magnaporthe grisea by use of polymerase chain reaction. a pair of degenerate primers based on conserved zymogen-type chitin synthase sequences amplified a approximately 600-bp product containing three chitin synthase gene fragments. a second pair of degenerate primers, based on conserved sequences between the chitin synthases 3 of saccharomyces cerevisiae and candida albicans, amplified a single 770-bp fragment. the four corresponding amino ...19989711845
a retrotransposon family from the pufferfish (fugu) fugu rubripes.in this study we describe the isolation and characterisation of the first full-length vertebrate retrotransposon. knowledge of vertebrate gypsy ltr-retrotransposons has been limited to short internal sequences from three fish and a corrupt sequence from a salamander. this paper describes the sequence of a full-length (5.645 kb) retrotransposon from the fugu fish fugu rubripes. the retrotransposon, termed sushi-ichi (032h04), is a representative of a retrotransposon family (sushi) found as multip ...19989714821
acropetal: a genetic locus required for conidiophore architecture and pathogenicity in the rice blast fungus.fungal spores are a primary means of dissemination and are the major sources of inoculum in pathogenic species. sporulation in the rice blast fungus magnaporthe grisea involves the production of three-celled conidia, borne sympodially on an aerial conidiophore. a disease cycle initiates when spores are dispersed and attach to the rice plant surface. using insertional mutagenesis we have identified a major regulator of conidiophore morphogenesis in m. grisea. a null mutation in the acropetal (acr ...19989742203
fungal avirulence genes: structure and possible functions.avirulence (avr) genes exist in many fungi that share a gene-for-gene relationship with their host plant. they represent unique genetic determinants that prevent fungi from causing disease on plants that possess matching resistance (r) genes. interaction between elicitors (primary or secondary products of avr genes) and host receptors in resistant plants causes induction of various defense responses often involving a hypersensitive response. avr genes have been successfully isolated by reverse g ...19989756710
construction of a bac library of the rice blast fungus magnaporthe grisea and finding specific genome regions in which its transposons tend to cluster.we have constructed a bac library of the rice blast fungus magnaporthe grisea consisting of 5760 clones. the insert size ranged from 35 to 175 kbp, with an average of 120 kbp. the library is about 18 genomes equivalent, therefore covering more than 99.999% of the genome. this library is the first to be constructed using a rice pathogenic wild type isolate. improved high molecular weight dna size fractionating helped to construct the library with high efficiency. total library clones were arrange ...19989757557
isolation of adenylate cyclase gene-specific sequences from ophiostoma novo-ulmi, candida albicans, and agaricus bisporus by pcr.degenerate primers corresponding to consensus sequences in the catalytic domains of known fungal adenylate cyclases were used to isolate gene-specific homologs from the dutch elm disease pathogen ophiostoma novo-ulmi, the dimorphic human pathogen candida albicans, and the commercial mushroom agaricus bisporus. all three fungi gave the expected pcr product of about 390 bp. computer searches of the databases revealed that the products generated from o. novo-ulmi and c. albicans were highly similar ...19989767719
inactivation of the mitogen-activated protein kinase mps1 from the rice blast fungus prevents penetration of host cells but allows activation of plant defense responses.the rice blast fungus, magnaporthe grisea, generates enormous turgor pressure within a specialized cell called the appressorium to breach the surface of host plant cells. here, we show that a mitogen-activated protein kinase, mps1, is essential for appressorium penetration. mps1 is 85% similar to yeast slt2 mitogen-activated protein kinase and can rescue the thermosensitive growth of slt2 null mutants. the mps1-1delta mutants of m. grisea have some phenotypes in common with slt2 mutants of yeast ...19989770551
chromosome walking to the avr1-co39 avirulence gene of magnaporthe grisea: discrepancy between the physical and genetic maps.the avrco39 gene conferring avirulence toward rice cultivar co39 was previously mapped to chromosome 1 of magnaporthe grisea between cosegregating markers ch5-120h and 1.2h and marker 5-10-f. in the present study, this region of the chromosome was physically mapped using reca-mediated achilles' cleavage. cleavage of genomic dna sequences within ch5-120h and 5-10-f liberated a 610-kb restriction fragment, representing the physical distance between these markers. chromosome walking was initiated f ...19989799257
signaling via camp in fungi: interconnections with mitogen-activated protein kinase pathways.the camp signal transduction pathway controls a wide variety of processes in fungi. for example, considerable progress has been made in describing the involvement of camp pathway components in the control of morphogenesis in saccharomyces cerevisiae, ustilago maydis, and magnaporthe grisea. these morphological processes include the establishment of filamentous growth in s. cerevisiae and u. maydis, and the differentiation of an appressorial infection structure in m. grisea. the discovery that ap ...19989799282
transcriptional activation of the alternative oxidase gene of the fungus magnaporthe grisea by a respiratory-inhibiting fungicide and hydrogen peroxide.alternative oxidase (aox) is dramatically induced when the fungus magnaporthe grisea is incubated with the fungicide ssf-126, which interacts with the cytochrome bc1 complex in the electron transport system of mitochondria. a full-length cdna for the alternative oxidase gene (aox) was obtained, and the deduced amino acid sequence revealed marked similarity to other aoxs, but lacks two cysteine residues at corresponding sites which are conserved in plant aoxs and play essential roles in the post- ...19989804939
cerebrosides a and c, sphingolipid elicitors of hypersensitive cell death and phytoalexin accumulation in rice plants.when plants interact with certain pathogens, they protect themselves by generating various chemical and physical barriers called the hypersensitive response. these barriers are induced by molecules called elicitors that are produced by pathogens. in the present study, the most active elicitors of the hypersensitive response in rice were isolated from the rice pathogenic fungus magnaporthe grisea, and their structures were identified as cerebrosides a and c, sphingolipids that were previously iso ...19989822670
calcium/calmodulin-dependent signaling for appressorium formation in the plant pathogenic fungus magnaporthe grisea.magnaporthe grisea, the causal agent of rice blast, forms a dome-shaped melanized infection structure, an appressorium, to infect its host. environmental cues that induce appressorium formation by this fungus include hydrophobicity and hardness of contact surface, and chemicals from the host. to determine if the calcium/calmodulin-dependent signaling systems are involved in appressorium formation in m. grisea, we tested the effects of the calcium chelator, calcium ionophore, diverse intracellula ...19989895122
a novel 17beta-hydroxysteroid dehydrogenase in the fungus cochliobolus lunatus: new insights into the evolution of steroid-hormone signalling.17beta-hydroxysteroid dehydrogenase (17beta-hsd) from the filamentous fungus cochliobolus lunatus (17beta-hsdcl) catalyses the reduction of steroids and of several o- and p-quinones. after purification of the enzyme, its partial amino acid sequence was determined. a pcr fragment amplified with primers derived from peptide sequences was generated for screening the coch. lunatus cdna library. three independent full-length cdna clones were isolated and sequenced, revealing an 810-bp open reading fr ...19999895285
structure-based design of potent inhibitors of scytalone dehydratase: displacement of a water molecule from the active site.scytalone dehydratase (sd) is a molecular target of inhibitor design efforts aimed at protecting rice plants from the fungal disease caused by magnaporthe grisea. as determined from x-ray diffraction data of an sd-inhibitor complex [lundqvist et al. (1994) structure (london) 2, 937-944], there is an extended hydrogen-bonding network between protein side chains, the inhibitor, and two bound water molecules. from models of sd complexed to quinazoline and benztriazine inhibitors, a new class of pot ...19989922139
an atp-driven efflux pump is a novel pathogenicity factor in rice blast disease.cells tolerate exposure to cytotoxic compounds through the action of atp-driven efflux pumps belonging to the atp-binding cassette (abc) superfamily of membrane transporters. phytopathogenic fungi encounter toxic environments during plant invasion as a result of the plant defense response. here we demonstrate the requirement for an abc transporter during host infection by the fungal plant pathogen magnaporthe grisea. the abc1 gene was identified in an insertional mutagenesis screen for pathogeni ...19999927411
infection-related development in the rice blast fungus magnaporthe grisea.recent developments have been made in the identification of signal transduction pathways and gene products involved in the infection-related development of the rice blast fungus, magnaporthe grisea. it has been established that camp-dependent and map kinase-mediated signaling are both critical for appressorium morphogenesis and function. these signaling pathways may act downstream of hydrophobin-mediated surface sensing by the growing germ tube. several genes have been identified that are requir ...199810066544
isolation, characterization and disruption of the area nitrogen regulatory gene of gibberella fujikuroi.the gene area-gf, a homologue of the major nitrogen regulatory genes nit-2, area, nre and nut1 of neurospora crassa, aspergillus nidulans, penicillium chrysogenum and magnaporthe grisea, respectively, was cloned from the gibberellin (ga)-producing rice pathogen gibberella fujikuroi. area-gf encodes a protein of 972 amino acid residues which contains a single putative zinc finger dna-binding domain that is at least 98% identical to the zinc finger domains of the homologous fungal proteins. the ar ...199910071216
lesion mimic mutants of rice with alterations in early signaling events of defense.we screened 93 lesion mimic mutants of rice for resistance to the blast fungus, magnaporthe grisea, and found eight mutants that exhibited significant resistance to the fungus. we called these mutants cdr (cell death and resistance) and further analyzed three of them. two mutations, cdr1 and cdr2, were recessive and one, cdr3, was dominant. many small brownish lesions developed over the entire leaf of the mutants 20-50 days after sowing. tunel staining revealed that dna fragmentation occurred in ...199910205906
early expression of the calmodulin gene, which precedes appressorium formation in magnaporthe grisea, is inhibited by self-inhibitors and requires surface attachment.fungal conidia contain chemicals that inhibit germination and appressorium formation until they are well dispersed in a favorable environment. recently, such self-inhibitors were found to be present on the conidia of magnaporthe grisea, and plant surface waxes were found to relieve this self-inhibition. to determine whether the self-inhibitors suppress the expression of early genes involved in the germination and differentiation of conidia, the calmodulin gene was chosen as a representative earl ...199910348871
high-resolution structures of scytalone dehydratase-inhibitor complexes crystallized at physiological ph.scytalone dehydratase is a molecular target of inhibitor design efforts aimed at preventing the fungal disease caused by magnaporthe grisea. a method for cocrystallization of enzyme with inhibitors at neutral ph has produced several crystal structures of enzyme-inhibitor complexes at resolutions ranging from 1.5 to 2.2 a. four high resolution structures of different enzyme-inhibitor complexes are described. in contrast to the original x-ray structure of the enzyme, the four new structures have w ...199910382670
population structure and dynamics of magnaporthe grisea in the indian himalayas.the population genetics of magnaporthe grisea, the rice blast pathogen, were analyzed in a center of rice diversity (the uttar pradesh hills of the indian himalayas) using multilocus and single-, or low-copy, dna markers. based on dna fingerprinting with the multilocus probe mgr586 and single-locus probes, 157 haplotypes clustered into 56 lineages (at >/=70% mgr586 band similarity, each with unique single-locus profiles) and high diversity indices were detected among 458 isolates collected from ...199910388817
the pib gene for rice blast resistance belongs to the nucleotide binding and leucine-rich repeat class of plant disease resistance genes.rice blast, caused by the fungal pathogen magnaporthe grisea, is one of the most serious diseases of rice. here we describe the isolation and characterization of pib, one of the rice blast resistance genes. the pib gene was isolated by a map-based cloning strategy. the deduced amino acid sequence of the pib gene product contains a nucleotide binding site (nbs) and leucine-rich repeats (lrrs); thus, pib is a member of the nbs-lrr class of plant disease resistance genes. interestingly, a duplicati ...199910417726
isolation of pheromone precursor genes of magnaporthe grisea.in heterothallic ascomycetes one mating partner serves as the source of female tissue and is fertilized with spermatia from a partner of the opposite mating type. the role of pheromone signaling in mating is thought to involve recognition of cells of the opposite mating type. we have isolated two putative pheromone precursor genes of magnaporthe grisea. the genes are present in both mating types of the fungus but they are expressed in a mating type-specific manner. the mf1-1 gene, expressed in m ...199910441451
physical map and organization of chromosome 7 in the rice blast fungus, magnaporthe grisea.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 ...199910447509
defence signalling pathways in cereals.the combination of mutational and molecular studies has shed light on the role of reactive oxygen intermediates and programmed cell death in cereal disease resistance mechanisms. rice rac1 and barley rar1 represent conserved disease resistance signalling genes, which may have related functions in animals. the analysis of non-pathogenic magnaporthe grisea mutants may provide novel tools to study host defence pathways.199910459000
stereoselective carveol dehydrogenase from rhodococcus erythropolis dcl14. a novel nicotinoprotein belonging to the short chain dehydrogenase/reductase superfamily.a novel nicotinoprotein, catalyzing the dichlorophenolindophenol-dependent oxidation of carveol to carvone, was purified to homogeneity from rhodococcus erythropolis dcl14. the enzyme is specifically induced after growth on limonene and carveol. dichlorophenolindophenol-dependent carveol dehydrogenase (cdh) is a homotetramer of 120 kda with each subunit containing a tightly bound nad(h) molecule. the enzyme is optimally active at ph 5.5 and 50 degrees c and displays a broad substrate specificity ...199910473585
degenerate maggy elements in a subgroup of pyricularia grisea: a possible example of successful capture of a genetic invader by a fungal genome.the ltr-retrotransposon maggy is found sporadically in isolates of pyricularia grisea (magnaporthe grisea). based on a dendrogram constructed by rflp analysis of rdna, isolates that carry maggy elements were classified into a single cluster that comprised four rdna types. however, in a few members of this cluster, exemplified by isolates from common millet (panicum miliaceum), the maggy element has distinct features. southern analysis suggested that these isolates possessed a single copy of a ma ...199910485287
remi mutagenesis and identification of pathogenic mutants in blast fungus (magnaporthe grisea).blast fungus' mutant, which is very difficult to obtain, is the key substance in the study of the relation between pathogen and plant. rice-aichi-ashahi was used as the host and plasmid pbf101 or pcsn43 as foreign dna fragment, and remi mutagenesis was applied to tag the pathogenic sequence in rice blast fungus m.grisea. three mutants (r2h65, r2h69 and r2b1565) related to pathogenicity were recovered from several hundreds of transformants. r2h69 and r2h65 produced merely strange conidia which co ...199810503072
transposition of the retrotransposon maggy in heterologous species of filamentous fungi.maggy is a gypsy-like ltr retrotransposon isolated from the blast fungus pyricularia grisea (teleomorph, magnaporthe grisea). we examined transposition of maggy in three p. grisea isolates (wheat, finger millet, and crabgrass pathogen), which did not originally possess a maggy element, and in two heterologous species of filamentous fungi, colletotrichum lagenarium and p. zingiberi. genomic southern analysis of maggy transformants suggested that transposition of maggy occurred in all filamentous ...199910511549
more than just a surface thing. rice infection by magnaporthe grisea 199910521513
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