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functional characterization of aspergillus nidulans homologues of saccharomyces cerevisiae spa2 and bud6.the importance of polarized growth for fungi has elicited significant effort directed at better understanding underlying mechanisms of polarization, with a focus on yeast systems. at sites of tip growth, multiple protein complexes assemble and coordinate to ensure that incoming building material reaches the appropriate destination sites, and polarized growth is maintained. one of these complexes is the polarisome that consists of spa2, bud6, pea2, and bni1 in saccharomyces cerevisiae. filamentou ...200616757736
[diagnosis and treatment of aspergillosis in the patients with chronic granulomatous disease].chronic granulomatous disease is a rare defect of phagocytosis. increased susceptibility to infections is limited to catalase positive bacteria and fungi. aspergillus spp was reported as the increased clinical problem and the main cause of the deaths.200616758737
outdoor environmental levels of aspergillus spp. conidia over a wide geographical area.unfortunately, little information is available on the 'normal' air and water load of aspergillus spores and their seasonal changes. we describe the air and water load of aspergillus spores across the province of madrid (spain). we collected samples of air and water (332 samples of air and 148 of water) from selected points and taps (urban and rural environment) in summer, autumn, winter and spring. temperature, wind speed and humidity at each point were obtained. we collected a total of 369 aspe ...200616772229
the ambient ph response rim pathway in yarrowia lipolytica: identification of ylrim9 and characterization of its role in dimorphism.yarrowia lipolytica is a dimorphic fungus that secretes either an acidic or an alkaline protease depending on the environmental ph. previous results have indicated that secretion of the alkaline protease is under control of the ph signaling pal/rim pathway originally described in aspergillus nidulans. several y. lipolytica mutants defective in some rim components of this pathway have been previously isolated and the rim genes characterized. in the present study, y. lipolytica rim9 (pali) gene (y ...200616775780
reducing the cost of resistance; experimental evolution in the filamentous fungus aspergillus nidulans.we have studied compensatory evolution in a fludioxonil resistant mutant of the filamentous fungus aspergillus nidulans. in an evolution experiment lasting for 27 weeks (about 3000 cell cycles) 35 parallel strains of this mutant evolved in three different environmental conditions. our results show a severe cost of resistance (56%) in the absence of fludioxonil and in all conditions the mutant strain was able to restore fitness without loss of the resistance. in several cases, the evolved strain ...200616780512
the zn(ii)2cys6 putative transcription factor nosa controls fruiting body formation in aspergillus nidulans.the filamentous fungus aspergillus nidulans reproduces asexually with conidiospores and sexually with ascospores, both of which are the result of complex morphogenetic pathways. the developmental decisions for both ways of reproduction largely depend on the action of stage-specific transcription factors. here we have characterized the putative zn(ii)(2)cys(6) transcription factor nosa (number of sexual spores), a protein of 675 aa, which shares 44% sequence identity to pro1 from sordaria macrosp ...200616780567
consecutive gene deletions in aspergillus nidulans: application of the cre/loxp system.the ability to perform multiple gene deletions is an important tool for conducting functional genomics. we report the development of a sequential gene deletion protocol for the filamentous fungus aspergillus nidulans using the cre/loxp recombinase system of bacteriophage p1. a recyclable genetic marker has been constructed by incorporating loxp direct repeats either side of the neurospora crassa pyr-4 gene (encodes orotidine 5'-monophosphate decarboxylase) which is able to complement the a. nidu ...200616783565
chemical characterization and quantification of siderophores produced by marine and terrestrial aspergilli.ten aspergilli (five each from marine and terrestrial habitats) were screened for siderophore production. all test isolates produced siderophores as indicated by a positive reaction in the fecl(3) test, chrome azurol sulphonate assay, and chrome azurol sulphonate agar plate test. further, the test isolates were compared for their siderophore production potential and chemical characteristics. examination of the chemical nature of the siderophores revealed that all test isolates produced hydroxama ...200616788730
a phosphoglucose isomerase mutant in aspergillus nidulans is defective in hyphal polarity and conidiation.upon germination aspergillus nidulans swom1 exhibits abnormal development by extending a primary germ tube that quickly reverts to isotropic growth and results in an enlarged, swollen apex with pronounced wall thickenings. apical lysis occurs in 38% of the germlings. a point mutation in the an6037.3 gene encoding the only phosphoglucose isomerase in a. nidulans is responsible for the defect. loss of polarity is bypassed when glucose is replaced with alternate carbon sources but in all cases the ...200616798030
lipid signaling in pathogenic fungi.recent studies have highlighted the importance of lipid signaling molecules in the development and pathogenicity of clinically important fungi. in cryptococcus neoformans, sphingolipid-derived diacylglycerol has been shown to induce the transcription of the putative virulence factor app1, which inhibits the phagocytosis of fungal cells by alveolar macrophages, as well as to activate the protein kinase c pkc1, which promotes cell-wall stability and increased melanin production. in candida albican ...200616798065
a phe389leu substitution in erga confers terbinafine resistance in aspergillus fumigatus.replacement of phenylalanine with leucine at position 391 in squalene epoxidase was identified as being responsible for terbinafine resistance in mutants of aspergillus nidulans. the equivalent mutation was engineered into the erga gene of aspergillus fumigatus, resulting in an f389l substitution that also conferred resistance to this pathogenic mold.200616801438
mutants of aspergillus nidulans affected in asexual development. 200616809845
g-protein and camp-mediated signaling in aspergilli: a genomic perspective.we have carried out an in silico exploration of the genomes of aspergillus nidulans, aspergillus fumigatus, and aspergillus oryzae, and identified components of g-protein/camp-mediated signaling. putative g-protein coupled receptors (gpcrs) were distributed over nine classes. the gpcrs within classes were well conserved among aspergilli but varied in other ascomycetes. as previously observed in a. nidulans and other fungi, three galpha, one gbeta, and one ggamma subunits of g proteins were ident ...200616546420
[recombinant aspergillus niger glucose oxidase expressed in trichoderma reesei].it was expected that recombinant aspergillus niger glucose oxidase could be expressed in trichoderma reesei with stable activity. t. reesei cbhi promoter--cbhi ss. gene--a. niger glucose oxidase gene--t. reesei cbhi terminator--a. nidulans gpd promoter--e. coli hygromycin b phosphotransferase gene--a. nidulans trpc terminator--puc19 (pcbhgod) vector was constructed in e. coli dh5alpha by pcr application and gene cloning methods. t. reesei qm9414 protoplast was transformed by t. reesei cbhi promo ...200616572845
protein kinase c (pkca) of aspergillus nidulans is involved in penicillin production.the biosynthesis of the beta-lactam antibiotic penicillin in the filamentous fungus aspergillus nidulans is catalyzed by three enzymes that are encoded by the acva, ipna, and aata genes. a variety of cis-acting dna elements and regulatory factors form a complex regulatory network controlling these beta-lactam biosynthesis genes. regulators involved include the ccaat-binding complex ancf and anbh1. anbh1 acts as a repressor of the penicillin biosynthesis gene aata. until now, however, little info ...200616598003
antimicrobial, wound healing and antioxidant activity of plagiochasma appendiculatum lehm. et lind.plagiochasma appendiculatum (aytoniaceae) of the order marchantiales is widely used in the form of paste ethnomedicinally by gaddi tribe in kangra valley for treating skin diseases. in this context, antimicrobical potential of plagiochasma appendiculatum against a wide range of microorganisms was studied. to validate the ethnotherapeutic claims of the plant in skin diseases, wound healing activity was studied, besides antioxidant activity to understand the mechanism of wound healing activity. th ...200616600543
microscopy reveals disease control through novel effects on fungal development: a case study with an early-generation benzophenone fungicide.the benzophenones are a new class of agricultural fungicides that demonstrate protectant, curative and eradicative/antisporulant activity against powdery mildews. the chemistry is represented in the marketplace by the fungicide metrafenone, recently introduced by basf and discussed in the following paper. the benzophenones show no evidence of acting by previously identified biochemical mechanisms, nor do they show cross-resistance with existing fungicides. the value of microscopy in elucidating ...200616602068
isolation of mutations that bypass the requirement of the septation initiation network for septum formation and conidiation in aspergillus nidulans.the kinase cascade of the septation initiation network (sin), first revealed in fission yeast, activates the contraction of the actomyosin ring, and plays an essential role in fungal septation. mob1p, an evolutionarily conserved sin protein, is associated with the most downstream kinase of this cascade in fission yeast. in this study, the moba gene encoding a homologous protein was isolated from the filamentous fungus aspergillus nidulans, whose mycelium is made of multinucleate cells. the moba ...200616624915
the region in a subunit of the aspergillus ccaat-binding protein similar to the hap4p-recruiting domain of saccharomyces cerevisiae hap5p is not essential for transcriptional enhancement.the ccaat-binding complex in aspergillus species, known as the hap complex, consists of at least three subunits, hapb, hapc, and hape. each hap subunit contains an evolutionarily conserved core domain. in this study, a series of the truncated gene, which encodes the hape subunit of aspergillus oryzae, was constructed to survey the regions essential for the transcriptional enhancement of fungal genes. it was revealed that the non-conserved regions and the conserved region similar to the hap4p rec ...200616636442
developmental regulation of the glyoxylate cycle in the human pathogen penicillium marneffei.penicillium marneffei is a thermally dimorphic opportunistic human pathogen with a saprophytic filamentous hyphal form at 25 degrees c and a pathogenic unicellular yeast form at 37 degrees c. during infection. p. marneffei yeast cells exist intracellularly in macrophages. to cope with nutrient deprivation during the infection process, a number of pathogens employ the glyoxylate cycle to utilize fatty acids as carbon sources. the genes which constitute this pathway have been implicated in pathoge ...200617427290
differential expression of genes involved in iron metabolism in aspergillus fumigatus.the ability of fungi to survive in many environments is linked to their capacity to acquire essential nutrients. iron is generally complexed and available in very limited amounts. like bacteria, fungi have evolved highly specific systems for iron acquisition. production and uptake of iron-chelating siderophores has been shown to be important for certain human bacterial pathogens, as well as in fungal pathogens such as cryptococcus neoformans and fusarium graminearum. this system also enables the ...200617236162
effects of mutations in the ganb/rgsa g protein mediated signalling on the autolysis of aspergillus nidulans.physiological changes taking place in carbon-starved, autolysing cultures of aspergillus (emericella) nidulans strains with mutations in the ganb/rgsa heterotrimeric g protein signalling pathway were studied and compared. deletion of the ganb, rgsa or both genes did not alter markedly either the autolytic loss of biomass or the extracellular chitinase production. however, they caused a significant decrease in the proteinase formation, which was detected by measuring both extracellular enzyme act ...200617139616
identification of a novel gene, ure2, that functionally complements a urease-negative clinical strain of cryptococcus neoformans.a urease-negative serotype a strain of cryptococcus neoformans (b-4587) was isolated from the cerebrospinal fluid of an immunocompetent patient with a central nervous system infection. the ure1 gene encoding urease failed to complement the mutant phenotype. urease-positive clones of b-4587 obtained by complementing with a genomic library of strain h99 harboured an episomal plasmid containing dna inserts with homology to the suda gene of aspergillus nidulans. the gene harboured by these plasmids ...200617159224
fvve1 regulates filamentous growth, the ratio of microconidia to macroconidia and cell wall formation in fusarium verticillioides.the velvet gene, vea, co-ordinates asexual and sexual development in the homothallic fungal species aspergillus nidulans. studies in aspergillus parasiticus and aspergillus fumigatus demonstrated that vea also regulates morphological differentiation in these species. whether vea has the same role in morphogenesis in other fungal genera has not been investigated. in this work, we studied the role of the vea homologue, fvve1, in the heterothallic fungus fusarium verticillioides. deletion of fvve1 ...200617054442
regulatory genes controlling fatty acid catabolism and peroxisomal functions in the filamentous fungus aspergillus nidulans.the catabolism of fatty acids is important in the lifestyle of many fungi, including plant and animal pathogens. this has been investigated in aspergillus nidulans, which can grow on acetate and fatty acids as sources of carbon, resulting in the production of acetyl coenzyme a (coa). acetyl-coa is metabolized via the glyoxalate bypass, located in peroxisomes, enabling gluconeogenesis. acetate induction of enzymes specific for acetate utilization as well as glyoxalate bypass enzymes is via the zn ...200616682457
identification and analysis of essential aspergillus nidulans genes using the heterokaryon rescue technique.in the heterokaryon rescue technique, gene deletions are carried out using the pyrg nutritional marker to replace the coding region of target genes via homologous recombination in aspergillus nidulans. if an essential gene is deleted, the null allele is maintained in spontaneously generated heterokaryons that consist of two genetically distinct types of nuclei. one nuclear type has the essential gene deleted but has a functional pyrg allele (pyrg+). the other has the wild-type allele of the esse ...200617406500
fusion pcr and gene targeting in aspergillus nidulans.we describe a rapid method for the production of fusion pcr products that can be used, generally without band purification, to transform aspergillus nidulans. this technique can be used to replace genes; tag genes with fluorescent moeties or epitope tags; or replace endogenous promoters with regulatable promoters, by introducing an appropriate selective cassette (e.g., fluorescent protein + selectable marker). the relevant genomic fragments and cassette are first amplified separately by pcr usin ...200617406574
a defect in nir1, a nira-like transcription factor, confers morphological abnormalities and loss of pathogenicity in colletotrichum acutatum.summary a non-pathogenic mutant of colletotrichum acutatum, designated ca5, exhibited epiphytic hyphal growth and did not cause lesions on strawberry plants but grew necrotrophically when inoculated directly onto wounded stolons. in the absence of an external nitrogen source, the mutant exhibited extended germ-tube growth prior to appressorium formation. the deduced product of the impaired gene (nir1) is similar to nira, an aspergillus nidulans transcriptional regulator of nitrogen metabolism. i ...200620507451
in vitro activation, purification, and characterization of escherichia coli expressed aryl-alcohol oxidase, a unique h2o2-producing enzyme.aryl-alcohol oxidase (aao), a flavoenzyme with unique spectral and catalytic properties that provides h2o2 for fungal degradation of lignin, has been successfully activated in vitro after escherichia coli expression. the recombinant aao (aao*) protein was recovered from inclusion bodies of e. coli w3110 transformed with pflag1 containing the aao cdna from pleurotus eryngii. optimization of in vitro refolding yielded 75% active enzyme after incubation of aao* protein (10 microg/ml) for 80 h (at 1 ...200616039872
structure-activity relationships and enzyme inhibition of pantothenamide-type pantothenate kinase inhibitors.a set of novel pantothenamide-type analogues of the known staphylococcus aureus pantothenate kinase (sapank) inhibitors, n-pentyl, and n-heptylpantothenamide, was synthesized in three series. the first series of analogues (1-3) were designed as molecular probes of the pank binding site to elucidate important structure-activity relationships (sar). the second series of analogues (4-16) were designed using structural information obtained from the escherichia coli pank (ecpank) structure by targeti ...200616213731
g protein-coupled receptor gpr4 senses amino acids and activates the camp-pka pathway in cryptococcus neoformans.the galpha protein gpa1 governs the camp-pka signaling pathway and plays a central role in virulence and differentiation in the human fungal pathogen cryptococcus neoformans, but the signals and receptors that trigger this pathway were unknown. we identified seven putative proteins that share identity with known g protein-coupled receptors (gpcrs). one protein, gpr4, shares limited sequence identity with the dictyostelium discoideum camp receptor car1 and the aspergillus nidulans gpcr protein gp ...200616291861
efficient pcr-based gene targeting with a recyclable marker for aspergillus nidulans.the rapid accumulation of genomic sequences from a large number of eukaryotes, including numerous filamentous fungi, has created a tremendous scientific potential, which can only be realized if precise site-directed genome modifications, like gene deletions, promoter replacements, in-frame gfp fusions and specific point mutations can be made rapidly and reliably. the development of gene-targeting techniques in filamentous fungi and other higher eukaryotes has been hampered because foreign dna is ...200616289954
visualization of the endocytic pathway in the filamentous fungus aspergillus oryzae using an egfp-fused plasma membrane protein.endocytosis is an important process for cellular activities. however, in filamentous fungi, the existence of endocytosis has been so far elusive. in this study, we used aouapc-egfp, the fusion protein of a putative uric acid-xanthine permease with enhanced green fluorescent protein (egfp) in aspergillus oryzae, to examine whether the endocytic process occurs or not. upon the addition of ammonium into the medium the fusion protein was internalized from the plasma membrane. the internalization of ...200616380079
flug-dependent asexual development in aspergillus nidulans occurs via derepression.the asexual spore is one of the most crucial factors contributing to the fecundity and fitness of filamentous fungi. although the developmental activator flug was shown to be necessary for activation of asexual sporulation (conidiation) and production of the carcinogenic mycotoxin sterigmatocystin (st) in the model filamentous fungus aspergillus nidulans, the molecular mechanisms underlying the developmental switch have remained elusive. in this study, we report that the flug-mediated conidiatio ...200616387865
a versatile and efficient gene-targeting system for aspergillus nidulans.aspergillus nidulans is an important experimental organism, and it is a model organism for the genus aspergillus that includes serious pathogens as well as commercially important organisms. gene targeting by homologous recombination during transformation is possible in a. nidulans, but the frequency of correct gene targeting is variable and often low. we have identified the a. nidulans homolog (nkua) of the human ku70 gene that is essential for nonhomologous end joining of dna in double-strand b ...200616387870
the gata factor area regulates localization and in vivo binding site occupancy of the nitrate activator nira.the gata factor area is a wide-domain regulator in aspergillus nidulans with transcriptional activation and chromatin remodelling functions. area interacts with the nitrate-specific zn(2)-c(6) cluster protein nira and both proteins cooperate to synergistically activate nitrate-responsive genes. we have previously established that nira in vivo dna binding site occupancy is area dependent and in this report we provide a mechanistic explanation for our previous findings. we now show that area regul ...200616390440
distinct ceramide synthases regulate polarized growth in the filamentous fungus aspergillus nidulans.in filamentous fungi, the stabilization of a polarity axis is likely to be a pivotal event underlying the emergence of a germ tube from a germinating spore. recent results implicate the polarisome in this process and also suggest that it requires localized membrane organization. here, we employ a chemical genetic approach to demonstrate that ceramide synthesis is necessary for the formation of a stable polarity axis in the model fungus aspergillus nidulans. we demonstrate that a novel compound ( ...200616394102
the presence of gc-ag introns in neurospora crassa and other euascomycetes determined from analyses of complete genomes: implications for automated gene prediction.a combination of experimental and computational approaches was employed to identify introns with noncanonical gc-ag splice sites (gc-ag introns) within euascomycete genomes. evaluation of 2335 cdna-confirmed introns from neurospora crassa revealed 27 such introns (1.2%). a similar frequency (1.0%) of gc-ag introns was identified in fusarium graminearum, in which 3 of 292 cdna-confirmed introns contained gc-ag splice sites. computational analyses of the n. crassa genome using a gc-ag intron conse ...200616406724
regulation of hyphal morphogenesis and the dna damage response by the aspergillus nidulans atm homolog atma.ataxia telangiectasia (a-t) is an inherited disorder characterized by progressive loss of motor function and susceptibility to cancer. the most prominent clinical feature observed in a-t patients is the degeneration of purkinje motor neurons. numerous studies have emphasized the role of the affected gene product, atm, in the regulation of the dna damage response. however, in purkinje cells, the bulk of atm localizes to the cytoplasm and may play a role in vesicle trafficking. the nature of this ...200616415361
identification of the mste gene encoding a glucose-inducible, low affinity glucose transporter in aspergillus nidulans.the mste gene encoding a low affinity glucose transporter active during the germination of aspergillus nidulans conidia on glucose medium has been identified. mste expression also occurs in hyphae, is induced in the presence of other repressing carbon sources besides glucose, and is dependent on the function of the transcriptional repressor crea. the expression of mste and its subcellular distribution have been studied using a mste-sgfp fusion protein. concordant with data on mste expression, ms ...200616418173
farnesol-induced apoptosis in aspergillus nidulans reveals a possible mechanism for antagonistic interactions between fungi.the dimorphic fungus candida albicans secretes farnesol, which acts as a quorum-sensing molecule and prevents the yeast to mycelium conversion. in this study we examined the effect of farnesol in the filamentous fungus aspergillus nidulans. we show that externally added farnesol has no effect on hyphal morphogenesis; instead, it triggers morphological features characteristic of apoptosis. additional experiments suggest that mitochondria and reactive oxygen species (ros) participate in farnesol-i ...200616420349
tmpa, a member of a novel family of putative membrane flavoproteins, regulates asexual development in aspergillus nidulans.asexual reproduction (conidiation) in aspergillus nidulans is induced by environmental signals like exposure to air or nutrient starvation, and depends on brla gene activation. the study of 'fluffy' mutants showing delayed asexual development and reduced brla expression has defined the flug pathway, involved in regulation of this differentiation process. genetic characterization of a 'fluffy' mutant identified tmpa as a new gene involved in regulation of conidiation. tmpa defines a new family of ...200616420356
oxylipins act as determinants of natural product biosynthesis and seed colonization in aspergillus nidulans.secreted, hormone-like lipogenic molecules, called oxylipins, mediate the balance of asexual to sexual spore ratio in aspergillus nidulans. oxylipin production in this fungus is dependent on developmental regulation of three conserved fatty acid oxygenases, ppoa, ppob and ppoc. here, we show that in addition to altering spore ratios, loss of ppo genes affect natural product biosynthesis and seed colonization. deltappoa;deltappoc and deltappoa;deltappob;deltappoc mutants were unable to produce th ...200616420358
a global view of metabolites.fungi are rich sources of medically useful, as well as toxic, secondary metabolites. in this issue of chemistry & biology, bok et al. show that, in aspergillus nidulans, microarray analysis and manipulation of a global regulator can identify novel metabolite genes.200616426964
genomic mining for aspergillus natural products.the genus aspergillus is renowned for its ability to produce a myriad of bioactive secondary metabolites. although the propensity of biosynthetic genes to form contiguous clusters greatly facilitates assignment of putative secondary metabolite genes in the completed aspergillus genomes, such analysis cannot predict gene expression and, ultimately, product formation. to circumvent this deficiency, we have examined aspergillus nidulans microarrays for expressed secondary metabolite gene clusters b ...200616426969
evaluation of agrobacterium-mediated transformation of agaricus bisporus using a range of promoters linked to hygromycin resistance.there is interest in establishing genetic modification technologies for the cultivated mushroom agaricus bisporus, both for improved crop characteristics and for molecular pharming. for these methods to be successful, it is necessary to establish a set of transformation systems that include robust and reliable vectors for gene manipulation. in this article, we report the evaluation of a series of promoters for driving expression of the escherichia coli hph gene encoding hygromycin phosphotransfe ...200616444014
the aflatoxin biosynthesis cluster gene, aflx, encodes an oxidoreductase involved in conversion of versicolorin a to demethylsterigmatocystin.biosynthesis of the toxic and carcinogenic aflatoxins by the fungus aspergillus flavus is a complicated process involving more that 27 enzymes and regulatory factors encoded by a clustered group of genes. previous studies found that three enzymes, encoded by vera, ver-1, and afly, are required for conversion of versicolorin a (va), to demethylsterigmatocystin. we now show that a fourth enzyme, encoded by the previously uncharacterized gene, aflx (ordb), is also required for this conversion. a ho ...200616461654
a novel-type substrate-selectivity filter and er-exit determinants in the uapa purine transporter.we present a functional analysis of the last alpha-helical transmembrane segment (tms12) of uapa, a uric acid-xanthine/h+ symporter in aspergillus nidulans and member of the nucleobase-ascorbate transporter (nat) family. first, we performed a systematic mutational analysis of residue f528, located in the middle of tms12, which was known to be critical for uapa specificity. substitution of f528 with non-aromatic amino acid residues (ala, thr, ser, gln, asn) did not affect significantly the kineti ...200616464466
the aspergillus nidulans xprg (phog) gene encodes a putative transcriptional activator involved in the response to nutrient limitation.the aspergillus nidulans xprg gene is involved in the regulation of extracellular proteases. a plasmid which complemented the xprg2 mutation was shown to carry the phog gene, reported to encode an acid phosphatase. two phogdelta mutants were constructed and were identical in phenotype to an xprg2 mutant. null mutants were unable to use protein as a carbon or nitrogen source, have lost a repressible acid phosphatase and have pale conidial color. xprg shows similarity to the ndt80 transcriptional ...200616464624
intrinsic in vitro susceptibility of primary clinical isolates of aspergillus fumigatus, aspergillus terreus, aspergillus nidulans, candida albicans and candida lusitaniae against amphotericin b.a total of 60 clinical fungal isolates from patients without prior amphotericin b treatment and three control strains were evaluated for their intrinsic susceptibility to amphotericin b (amb) using microdilution, etest and disc diffusion assays, on three media each, roswell park memorial institute (rpmi) 1640, antibiotic medium 3 (am3) and high resolution medium. the fungal strains included isolates of aspergillus fumigatus (n = 10), aspergillus terreus (n = 12), aspergillus nidulans (n = 9), ca ...200616466441
clip-170 homologue and nude play overlapping roles in nudf localization in aspergillus nidulans.proteins in the cytoplasmic dynein pathway accumulate at the microtubule plus end, giving the appearance of comets when observed in live cells. the targeting mechanism for nudf (lis1/pac1) of aspergillus nidulans, a key component of the dynein pathway, has not been clear. previous studies have demonstrated physical interactions of nudf/lis1/pac1 with both nude/nudel/ndl1 and clip-170/bik1. here, we have identified the a. nidulans clip-170 homologue, clipa. the clipa deletion did not cause an obv ...200616467375
differential expression of aspergillus nidulans ammonium permease genes is regulated by gata transcription factor area.the movement of ammonium across biological membranes is mediated in both prokaryotes and eukaryotes by ammonium transport proteins (amt/mep) that constitute a family of related sequences. we have previously identified two ammonium permeases in aspergillus nidulans, encoded by the meaa and mepa genes. here we show that meaa is expressed in the presence of ammonium, consistent with the function of meaa as the main ammonium transporter required for optimal growth on ammonium as a nitrogen source. i ...200616467464
the phosducin-like protein phna is required for gbetagamma-mediated signaling for vegetative growth, developmental control, and toxin biosynthesis in aspergillus nidulans.phosducin or phosducin-like protein (phlp) is a positive regulator of gbetagamma activity. the gbeta (sfad) and ggamma (gpga) subunits function in vegetative growth and developmental control in the model filamentous fungus aspergillus nidulans. to better understand the nature of gbetagamma-mediated signaling, phna, encoding an a. nidulans phlp, has been studied. deletion of phna resulted in phenotypes almost identical to those caused by deletion of sfad, i.e., reduced biomass, asexual sporulatio ...200616467480
aspergillus nidulans class v and vi chitin synthases csma and csmb, each with a myosin motor-like domain, perform compensatory functions that are essential for hyphal tip growth.the polarized synthesis of cell wall components such as chitin is essential for the hyphal tip growth of filamentous fungi. the actin cytoskeleton is known to play important roles in the determination of hyphal polarity in aspergillus nidulans. previously, we suggested that csma, a chitin synthase with a myosin motor-like domain (mmd), was involved in polarized chitin synthesis in a manner dependent on the interaction between the mmd and the actin cytoskeleton. the genome database indicates that ...200616468983
genetic transformation of ascochyta rabiei using agrobacterium-mediated transformation.in order to study pathogenic mechanisms of the plant pathogen ascochyta rabiei, conditions for efficient transformation using agrobacterium-mediated transformation were investigated. hygromycin b resistance (hph) was superior to geneticin resistance (nptii) for selecting transformants, and the hph gene was more efficiently expressed by the aspergillus nidulans trpc promoter than by the cauliflower mosaic virus 35s promoter camv35s. co-cultivation on solid media for 72 h was optimal for generatin ...200616369840
analysis of the aspergillus nidulans thaumatin-like ceta gene and evidence for transcriptional repression of pyr4 expression in the ceta-disrupted strain.the asexual spore or conidium plays a critical role in the life cycle of many filamentous fungi. however, the process of conidial germination remains surprisingly obscure. to better understand this process at the molecular level we characterized the aspergillus nidulans ceta gene which is uniquely transcribed in conidiating cultures and whose transcript is significantly enriched in mature conidia. ceta is a member of a novel family of fungal genes of unknown function with homology to plant thaum ...200616376592
impact of fungal drug transporters on fungicide sensitivity, multidrug resistance and virulence.drug transporters are membrane proteins that provide protection for organisms against natural toxic products and fungicides. in plant pathogens, drug transporters function in baseline sensitivity to fungicides, multidrug resistance (mdr) and virulence on host plants. this paper describes drug transporters of the filamentous fungi aspergillus nidulans (eidam) winter, botrytis cinerea pers and mycosphaerella graminicola (fückel) schroter that function in fungicide sensitivity and resistance. the f ...200616475240
nonribosomal peptide synthesis in schizosaccharomyces pombe and the architectures of ferrichrome-type siderophore synthetases in fungi.a nonribosomal peptide synthetase (nrps) in schizosaccharomyces pombe, which possesses an unusual structure incorporating three adenylation domains, six thiolation domains and six condensation domains, has been shown to produce the cyclohexapeptide siderophore ferrichrome. one of the adenylation domains is truncated and contains a distorted key motif. substrate-binding specificities of the remaining two domains were assigned by molecular modelling to glycine and to n-acetyl-n-hydroxy-l-ornithine ...200616502473
common features and interesting differences in transcriptional responses to secretion stress in the fungi trichoderma reesei and saccharomyces cerevisiae.secretion stress is caused by compromised folding, modification or transport of proteins in the secretory pathway. in fungi, induction of genes in response to secretion stress is mediated mainly by the unfolded protein response (upr) pathway. this study aims at uncovering transcriptional responses occurring in the filamentous fungi trichoderma reesei exposed to secretion stress and comparing these to those found in the yeast saccharomyces cerevisiae.200616504068
induction of temperate cyanophage as-1 by heavy metal--copper.it has been reported that some marine cyanophage are temperate and can be induced from a lysogenic phase to a lytic phase by different agents such as heavy metals. however, to date no significant reports have focused on the temperate nature of freshwater cyanophage/cyanobacteria. previous experiments with cyanophage as-1 and cyanobacteria anacystis nidulans have provided some evidence that as-1 may have a lysogenic life cycle in addition to the characterized lytic cycle.200616504132
depletion of aspergillus nidulans cota causes a severe polarity defect which is not suppressed by the nuclear migration mutation nuda2.the aspergillus nidulans homologue of neurospora crassa cot-1, cota, encoding a member of the ndr protein kinase family, has been cloned and expressed under the control of the conditional alca promoter. depletion of cota by repression of the alca promoter led to a severe growth defect accompanied by loss of polarity. germlings show greatly enlarged volume of the spores and hyphae, accompanied by an increase in number of nuclei per compartment, though the nucleus/volume ratio is not significantly ...200616506053
functional characterization of the putative aspergillus nidulans poly(adp-ribose) polymerase homolog prpa.poly(adp-ribose) polymerase (parp) is a highly conserved enzyme involved in multiple aspects of animal and plant cell physiology. for example, parp is thought to be intimately involved in the early signaling events that trigger the dna damage response. however, the genetic dissection of parp function has been hindered by the presence of multiple homologs in most animal and plant species. here, we present the first functional characterization of a putative parp homolog (prpa) in a microbial syste ...200616510786
the product of the shr3 orthologue of aspergillus nidulans has restricted range of amino acid transporter targets.the shra gene of aspergillus nidulans codes for a structural and functional homologue of shr3p, a yeast er membrane protein, which plays a crucial role in the secretory pathway of yeast amino acid permeases. shra is a single-copy gene, whose expression is early activated during germination of a. nidulans conidiospores. shra is localized in the er of the fungal cells and partially complements the shr3delta phenotype. differently from saccharomyces cerevisiae, where shr3p is necessary for membrane ...200616531082
functional analysis of alcs, a gene of the alc cluster in aspergillus nidulans.the ethanol utilization pathway (alc system) of aspergillus nidulans requires two structural genes, alca and alda, which encode the two enzymes (alcohol dehydrogenase and aldehyde dehydrogenase, respectively) allowing conversion of ethanol into acetate via acetyldehyde, and a regulatory gene, alcr, encoding the pathway-specific autoregulated transcriptional activator. the alcr and alca genes are clustered with three other genes that are also positively regulated by alcr, although they are dispen ...200616531087
detection of unknown toxic mycotoxins inaspergillus nidulans using a structure-activity approach.mycotoxins are secondary metabolites of filamentous fungi that can cause various acute and chronic toxic effects in humans. previous work by büngeret al. exhibited that the cytotoxicityof aspergillus nidulans, one of the most frequent toxigenic moulds in composting plants, could not be explained by its content of identified mycotoxins. the presence of additional mycotoxins or other toxic prinpiples was assumed, which may be detected by a structure-activity approach.an hplc-diode array detector m ...200623605709
occurrence of fungal species and mycotoxins from decayed sugarcane (saccharrum officinarum) in egypt.seventy-three fungal species belonging to forty-three genera were isolated from 40 samples of saccharrum officinarum (collected from naage-hamadi canal in qena governorate, egypt). aspergillus, trichoderma, mucor and pythium were the most common genera on the two isolation media. the dominant species of aspergillus were a. niger, a. flavus, a. ustus, a. terreus and a. wentii. some species were dominant on 40 g/l sucrose such as aspergillus niger, a. flavus, emericella nidulans, trichoderma virid ...200524049478
mapping the primary structure of copper/topaquinone-containing methylamine oxidase from aspergillus niger.the amino acid sequence of methylamine oxidase (meao) from the fungus aspergillus niger was analyzed using mass spectrometry (ms). first, meao was characterized by an accurate molar mass of 72.4 kda of the monomer measured using maldi-tof-ms and by a pi value of 5.8 determined by isoelectric focusing. maldi-tof-ms revealed a clear peptide mass fingerprint after tryptic digestion, which did not provide any relevant hit when searched against a nonredundant protein database and was different from t ...200516475499
agrobacterium tumefaciens-mediated transformation of mucor circinelloides.the agrobacterium tumefaciens-mediated transformation of the zygomycetous fungus mucor circinelloides is described. a method was also developed for the hygromycin b-based selection of mucor transformants. transformation with the hygromycin b phosphotransferase gene of escherichia coli controlled by the heterologous aspergillus nidulans trpc promoter resulted in hygromycin b-resistant clones. the presence of the hygromycin resistance gene in the genome of the transformants was verified by polymer ...200516475501
genomics of aspergillus fumigatus.aspergillus fumigatus is a filamentous fungal saprophyte that is ubiquitous in the environment. it is also a human pathogen and induces allergenic response, negatively impacting health care and associated costs significantly around the world. much of the basic biology of this organism is only poorly understood, but the recent completion and publication of its genome sequence provides an excellent tool for researchers to gain insight into these processes. in this review we will summarize some of ...200516499415
development of a modified positive selection medium that allows to isolate aspergillus oryzae strains cured of the integrated niad-based plasmid.the nitrate reductase gene (niad) is the most frequently utilized as a selectable marker for homologous integration at the niad locus of aspergillus oryzae. in this study we developed a method for curing of the niad-based plasmid integrated on the a. oryzae genome. positive selection using a modified chlorate medium containing leucine as a nitrogen source enabled efficient isolation of the strains deficient in nitrate assimilation from the niad(+) transformant. pcr analysis of the strains confir ...200516377911
sequencing of aspergillus nidulans and comparative analysis with a. fumigatus and a. oryzae.the aspergilli comprise a diverse group of filamentous fungi spanning over 200 million years of evolution. here we report the genome sequence of the model organism aspergillus nidulans, and a comparative study with aspergillus fumigatus, a serious human pathogen, and aspergillus oryzae, used in the production of sake, miso and soy sauce. our analysis of genome structure provided a quantitative evaluation of forces driving long-term eukaryotic genome evolution. it also led to an experimentally va ...200516372000
genome sequencing and analysis of aspergillus oryzae.the genome of aspergillus oryzae, a fungus important for the production of traditional fermented foods and beverages in japan, has been sequenced. the ability to secrete large amounts of proteins and the development of a transformation system have facilitated the use of a. oryzae in modern biotechnology. although both a. oryzae and aspergillus flavus belong to the section flavi of the subgenus circumdati of aspergillus, a. oryzae, unlike a. flavus, does not produce aflatoxin, and its long histor ...200516372010
purification and properties of an extracellular endo-1,4-beta-xylanase from penicillium citrinum and characterization of the encoding gene.an extracellular endo-1,4-beta-xylanase was purified from the culture filtrate of a filamentous fungus penicillium citrinum ferm p-15944 grown on birch-wood xylan. the purified enzyme showed a single band on sds-page with an apparent m(r) of 20,000 and had an isoelectric point below 3.5. xylanase activity was optimal at ph 5.0 and 55 degrees c. the genomic dna and cdnas encoding this protein were cloned and sequenced. southern blot analysis indicated that the xylanase gene (xyna) was present as ...200516473771
glass-fiber disks provide suitable medium to study polyol production and gene expression in eurotium rubrum.eurotium species often dominate the fungal population in stored grain and are responsible for spoilage. in this study we tested the usefulness of glass fiber disks to aid the analysis of growth, polyol content and gene expression in e. rubrum in response to various water activities. growth measurements based on ergosterol content and conidial production indicated that e. rubrum grew as well at 0.86 aw as 0.98 aw. the rate of growth was considerably reduced at 0.83 aw and 0.78 aw. in contrast, un ...200516457343
genomics reveals traces of fungal phenylpropanoid-flavonoid metabolic pathway in the f ilamentous fungus aspergillus oryzae.fungal secondary metabolites constitute a wide variety of compounds which either play a vital role in agricultural, pharmaceutical and industrial contexts, or have devastating effects on agriculture, animal and human affairs by virtue of their toxigenicity. owing to their beneficial and deleterious characteristics, these complex compounds and the genes responsible for their synthesis have been the subjects of extensive investigation by microbiologists and pharmacologists. a majority of the funga ...200516410762
screening of growth- or development-related genes by using genomic library with inducible promoter in aspergillus nidulans.using the genomic library constructed at the downstream of the niia promoter, which induces the over-expression of an inserted dna fragment, we have attempted to screen the genes affecting growth or development by over-expression. the wild-type strain was transformed using the ama-niia(p) library and cultured on 1.2 m sorbitol media, in which asexual sporulation is induced, but sexual development is repressed. over 100,000 strains transformed to pyrg(+) were analyzed with regard to any changes i ...200516410769
tracing the endocytic pathway of aspergillus nidulans with fm4-64.simple procedures using fm4-64 to follow membrane internalization and transport to the vacuolar system and endomembranes in aspergillus nidulans are described. fm4-64 internalization is energy, temperature and f-actin dependent, strongly suggesting that it occurs by endocytosis. the dye sequentially labels: (i) cortical punctuate organelles whose motility resembles that of yeast actin patches; (ii) approximately 0.7 microm circular, hollow structures representing mature endosome/vacuole; and (ii ...200516291501
a mapk gene from dead sea fungus confers stress tolerance to lithium salt and freezing-thawing: prospects for saline agriculture.the dead sea is one of the most saline lakes on earth ( approximately 340 g/liter salinity) and is approximately 10 times saltier than the oceans. eurotium herbariorum, a common fungal species, was isolated from its water. ehhog gene, encoding a mitogen-activated protein kinase (mapk) that plays an essential role in the osmoregulatory pathway in yeast and many other eukaryotes, was isolated from e. herbariorum. the deduced amino acid sequences of ehhog indicated high similarity with homologous g ...200516365289
comparison of gene expression signatures of diamide, h2o2 and menadione exposed aspergillus nidulans cultures--linking genome-wide transcriptional changes to cellular physiology.in addition to their cytotoxic nature, reactive oxygen species (ros) are also signal molecules in diverse cellular processes in eukaryotic organisms. linking genome-wide transcriptional changes to cellular physiology in oxidative stress-exposed aspergillus nidulans cultures provides the opportunity to estimate the sizes of peroxide (o2(2-)), superoxide (o2*-) and glutathione/glutathione disulphide (gsh/gssg) redox imbalance responses.200516368011
deletions of endocytic components vps28 and vps32 affect growth at alkaline ph and virulence through both rim101-dependent and rim101-independent pathways in candida albicans.ambient ph signaling involves a cascade of conserved rim or pal products in ascomycetous yeasts or filamentous fungi, respectively. recent evidences in the fungi aspergillus nidulans, saccharomyces cerevisiae, yarrowia lipolytica, and candida albicans suggested that components of endosomal sorting complexes required for transport (escrt) involved in endocytic trafficking were needed for signal transduction along the rim pathway. in this study, we confirm these findings with c. albicans and show ...200516299290
c21orf5, a new member of dopey family involved in morphogenesis, could participate in neurological alterations and mental retardation in down syndrome.availability of the human genome sequence promises important progress in the understanding of human pathologies, particularly for multifactorial diseases. among these, down syndrome (ds) is the most frequent genetic cause of mental retardation. a critical region of chromosome 21, the down syndrome chromosomal region-1 (dcr-1), is responsible for many features of the ds phenotype including mental retardation. we studied dcr-1 c21orf5 as a new candidate gene for ds considering its restricted expre ...200516303751
cloning, expression, and characterization of an oligoxyloglucan reducing end-specific xyloglucanobiohydrolase from aspergillus nidulans.an oligoxyloglucan reducing end-specific xyloglucanobiohydrolase from the filamentous fungus aspergillus nidulans was cloned and expressed in pichia pastoris as a secreted histidine-tagged protein and purified by affinity chromatography. the enzyme acts on xyloglucan oligomers and releases the first two glycosyl residue segments from the reducing end, provided that neither the first glucose nor the xylose attached to the third glucose residue from the reducing end is not further substituted. the ...200516214120
nuclear accumulation of the gata factor area in response to complete nitrogen starvation by regulation of nuclear export.both the availability and the quality of nutrients affect cellular functions by controlling gene activity. area, a member of the gata family of transcription factors, globally activates expression of genes involved in nitrogen source utilization in aspergillus nidulans. the quality of the nitrogen source determines the level and activation capacity of area through controls at the level of area mrna stability and by interaction of area with the corepressor nmra. the availability of potential nitr ...200516215172
hdaa, a major class 2 histone deacetylase of aspergillus nidulans, affects growth under conditions of oxidative stress.histone deacetylases (hdacs) catalyze the removal of acetyl groups from the epsilon-amino group of distinct lysine residues in the amino-terminal tail of core histones. since the acetylation status of core histones plays a crucial role in fundamental processes in eukaryotic organisms, such as replication and regulation of transcription, recent research has focused on the enzymes responsible for the acetylation/deacetylation of core histones. very recently, we showed that hdaa, a member of the sa ...200516215180
development of aspergillus oryzae thia promoter as a tool for molecular biological studies.in filamentous fungi, the repertoire of promoters available for exogenous gene expression is limited. here, we report the development and application of the thiamine-regulatable thia promoter (pthia) in aspergillus oryzae as a tool for molecular biological studies. when pthia was used to express the enhanced green fluorescent protein (egfp) reporter, the fluorescence in the mycelia was either repressed or induced in the presence or absence of thiamine in the culture media, respectively. in addit ...200515727819
a c-terminal fragment of an intron-encoded maturase is sufficient for promoting group i intron splicing.group i introns often encode proteins that catalyze site-specific dna hydrolysis. some of these proteins have acquired the ability to promote splicing of their cognate intron, but whether these two activities reside in different regions of the protein remains obscure. a crystal structure of i-anii, a dual function intron-encoded protein, has shown that the protein has two pseudo-symmetric domains of equal size. each domain contacts its dna substrate on either side of two cleavage sites. as a fir ...200515769873
cloning and expression analysis of two catalase genes from aspergillus oryzae.fungi contain distinct genes encoding the same class of enzyme that are differentially regulated according to conditions. we cloned two catalase genes, cata and catb, from aspergillus oryzae. the cata gene predicts a 747-amino-acid polypeptide sharing 81% identity with aspergillus fumigatus catalase (cata) and 77% with aspergillus nidulans catalase (cata). the catb gene predicts a 725-amino-acid polypeptide sharing 82% identity with a. fumigatus catalase (catb) and 75% with a. nidulans catalase ...200516233832
photosensing fungi: phytochrome in the spotlight.red light triggers asexual development and represses sexual development in the fungus aspergillus nidulans. this response has been shown to require a phytochrome red/far-red light photoreceptor, fpha, which is cytoplasmic and binds a tetrapyrrole chromophore. fpha exhibits similarities to both plant and bacterial phytochromes.200516243020
the aspergillus nidulans phytochrome fpha represses sexual development in red light.phytochrome photoreceptors sense red and far-red light through photointerconversion between two stable conformations, a process mediated by a linear tetrapyrrole chromophore. originally, phytochromes were thought to be confined to photosynthetic organisms including cyanobacteria, but they have been recently discovered in heterotrophic bacteria and fungi, where little is known about their functions. it was shown previously in the ascomycetous fungus aspergillus nidulans that asexual sporulation i ...200516243030
protein o-mannosyltransferase a of aspergillus awamori is involved in o-mannosylation of glucoamylase i.industrially important extracellular enzymes from filamentous fungi are often o-mannosylated. the structure and function of the pmta (aapmta) gene encoding the protein o-d-mannosyltransferase of aspergillus awamori were characterized. the aapmta disruptant, designated aapmta, was constructed by homologous recombination. the strain aapmta exhibited fragile cell morphology with respect to hyphal extension, as well as swollen hyphae formation and conidia formation in potato dextrose medium. moreove ...200516272387
surface ultrastructure and elasticity in growing tips and mature regions of aspergillus hyphae describe wall maturation.this study reports the first direct, high-resolution physical and structural evidence of wall changes during hyphal tip growth, visualized by atomic force microscopy (afm) in aspergillus nidulans. images from afm and cryo-scanning electron microscopy provided comparable information, but afm was also able to image and physically probe living cells. afm images showed changes in the surface ultrastructure of a. nidulans hyphae, from newly deposited walls at hyphal tips to fully mature walls, as wel ...200516272389
aspergillus cyclooxygenase-like enzymes are associated with prostaglandin production and virulence.oxylipins comprise a family of oxygenated fatty acid-derived signaling molecules that initiate critical biological activities in animals, plants, and fungi. mammalian oxylipins, including the prostaglandins (pgs), mediate many immune and inflammation responses in animals. pg production by pathogenic microbes is theorized to play a role in pathogenesis. we have genetically characterized three aspergillus genes, ppoa, ppob, and ppoc, encoding fatty acid oxygenases similar in sequence to specific m ...200516040966
virulence comparisons of aspergillus nidulans mutants are confounded by the inflammatory response of p47phox-/- mice.while investigating the requirement for phagosomal alkalinization in the host defense against pulmonary aspergillosis, we observed high morbidity of p47(phox)(-/-) mice infected with ph-insensitive aspergillus nidulans mutants despite a paucity of fungal growth. fatal infection also resulted from a normally avirulent p-aminobenzoate auxotroph. this demonstrates that p47(phox)(-/-) murine immunity contributes significantly to a. nidulans lethality. these data have wider implications for microbial ...200516041040
lysine is catabolized to 2-aminoadipic acid in penicillium chrysogenum by an omega-aminotransferase and to saccharopine by a lysine 2-ketoglutarate reductase. characterization of the omega-aminotransferase.the biosynthesis and catabolism of lysine in penicillium chrysogenum is of great interest because these pathways provide 2-aminoadipic acid, a precursor of the tripeptide delta-l-2-aminoadipyl-l-cysteinyl-d-valine that is an intermediate in penicillin biosynthesis. in vivo conversion of labelled l-lysine into two different intermediates was demonstrated by hplc analysis of the intracellular amino acid pool. l-lysine is catabolized to 2-aminoadipic acid by an omega-aminotransferase and to sacchar ...200516049680
identification and molecular cloning of a gene encoding phospholipase a2 (plaa) from aspergillus nidulans.the plaa gene encoding a protein that contains the cytosolic phospholipase a(2) (cpla(2)) motif is cloned for the first time from the filamentous fungus, aspergillus nidulans. the translated 837 amino acid protein product of plaa comprises conserved lipase regions that are present in most mammalian cpla(2) homologs. high expression of plaa was observed in glucose-lactose medium by northern blot analyses. deletion mutants of plaa grew and formed conidia similar to the wild-type strain, but showed ...200516051517
rnase p cleaves transient structures in some riboswitches.rnase p from escherichia coli cleaves the coenzyme b12 riboswitch from e. coli and a similar one from bacillus subtilis. the cleavage sites do not occur in any recognizable structure, as judged from theoretical schemes that have been drawn for these 5' utrs. however, it is possible to draw a scheme that is a good representation of the e. coli cleavage site for rnase p and for the cleavage site in b. subtilis. these data indicate that transient structures are important in rnase p cleavage and in ...200516061811
regulation of secondary metabolism in filamentous fungi.fungal secondary metabolites are of intense interest to humankind due to their pharmaceutical (antibiotics) and/or toxic (mycotoxins) properties. in the past decade, tremendous progress has been made in understanding the genes that are associated with production of various fungal secondary metabolites. moreover, the regulatory mechanisms controlling biosynthesis of diverse groups of secondary metabolites have been unveiled. in this review, we present the current understanding of the genetic regu ...200516078891
the csnd/csne signalosome genes are involved in the aspergillus nidulans dna damage response.the signalosome (csn) is a conserved multiprotein complex involved in regulation of eukaryotic development and is also required to activate ribonucleotide reductase for dna synthesis. in aspergillus nidulans, csnd/csne are key regulators of sexual development. here, we investigated whether the csnd/csne genes are involved in the dna damage response in this fungus. the growth of the csnd/csne deletion mutants was reduced by subinhibitory concentrations of hydroxyurea, camptothecin, 4-nitroquinoli ...200516079239
expression of asexual developmental regulator gene abaa is affected in the double mutants of classes i and ii chitin synthase genes, chsc and chsa, of aspergillus nidulans.the chsa and chsc encode classes ii and i chitin synthases, respectively, of the filamentous fungus aspergillus nidulans. the deltachsa deltachsc double mutants (deltaac mutants) show defects in asexual development: a striking reduction in the number of conidiophores and aberrant conidiophore morphology. here, we examined the involvement of regulatory genes for asexual development (brla, abaa, and meda) in the conidiation defects of the deltaac mutants. spatial expression patterns of brla, abaa, ...200516082523
the pkab gene encoding the secondary protein kinase a catalytic subunit has a synthetic lethal interaction with pkaa and plays overlapping and opposite roles in aspergillus nidulans.filamentous fungal genomes contain two distantly related cyclic amp-dependent protein kinase a catalytic subunits (pkas), but only one pka is found to play a principal role. in aspergillus nidulans, pkaa is the primary pka that positively functions in vegetative growth and spore germination but negatively controls asexual sporulation and production of the mycotoxin sterigmatocystin. in this report, we present the identification and characterization of pkab, encoding the secondary pka in a. nidul ...200516087751
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