Publications

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genetic interactions of the aspergillus nidulans atmaatm homolog with different components of the dna damage response pathway.ataxia telangiectasia mutated (atm) is a phosphatidyl-3-kinase-related protein kinase that functions as a central regulator of the dna damage response in eukaryotic cells. in humans, mutations in atm cause the devastating neurodegenerative disease ataxia telangiectasia. previously, we characterized the homolog of atm (atma) in the filamentous fungus aspergillus nidulans. in addition to its expected role in the dna damage response, we found that atma is also required for polarized hyphal growth. ...200818245360
genetic analysis of the role of peroxisomes in the utilization of acetate and fatty acids in aspergillus nidulans.peroxisomes are organelles containing a diverse array of enzymes. in fungi they are important for carbon source utilization, pathogenesis, development, and secondary metabolism. we have studied aspergillus nidulans peroxin (pex) mutants isolated by virtue of their inability to grow on butyrate or by the inactivation of specific pex genes. while all pex mutants are able to form colonies, those unable to import pts1 proteins are partially defective in asexual and sexual development. the pex mutant ...200818245820
a novel screening method for cell wall mutants in aspergillus niger identifies udp-galactopyranose mutase as an important protein in fungal cell wall biosynthesis.to identify cell wall biosynthetic genes in filamentous fungi and thus potential targets for the discovery of new antifungals, we developed a novel screening method for cell wall mutants. it is based on our earlier observation that the aspergillus niger agsa gene, which encodes a putative alpha-glucan synthase, is strongly induced in response to cell wall stress. by placing the agsa promoter region in front of a selectable marker, the acetamidase (amds) gene of a. nidulans, we reasoned that cell ...200818245853
biochemical and molecular characterization of a putative endoglucanase in magnaporthe grisea.microbial pathogens secrete an array of cell wall-degrading enzymes to break down the structure of the host cell wall to facilitate colonization of the host tissue. to better understand their role in the pathogenesis, a putative endoglucanase from magnaporthe grisea was characterized in this paper. signalp-3.0 analysis indicates that the protein encoded by gene mgg_02532.5 in m. grisea (named mgegl1 for m. grisea endoglucanase 1) contains a secretory signal peptide. multiple alignment shows that ...200818247030
aspergillus nidulans hypb encodes a sec7-domain protein important for hyphal morphogenesis.aspergillus nidulans strains containing the hypb5 temperature sensitive allele have a restrictive phenotype of wide, highly-branched hyphae. the hypb locus was cloned by phenotype complementation using a genomic plasmid library. hypb5 is predicted gene an6709 in the a. nidulans genome database, which encodes a putative sec7 domain protein, likely to act early in copi-mediated vesicle formation for retrograde golgi to er transport. the a. nidulans hypb5 allele has a single mutation, cytosine to g ...200818248749
novel promoter sequence required for inductive expression of the aspergillus nidulans endoglucanase gene egla.expression of the egla gene, encoding for a major endoglucanse eg a in aspergillus nidulans, is induced by cellulose and cellobiose, but not by xylose. this suggests that induction is independent of xlnr, a transcriptional activator of xylanolytic and cellulolytic genes in aspergillus. mutational analysis of the egla promoter was performed to identify the novel cis-element responsible for xlnr-independent induction. the region spanning -153 to -138 (ccgtacctttttagga), designated cere(cellulose r ...200818256482
gfp-tagged expression analysis revealed that some histidine kinases of aspergillus nidulans show temporally and spatially different expression during the life cycle.his-asp phosphorelays are signal transduction mechanisms widely found in both prokaryotes and eukaryotes. the phosphorelay comprises three types of signal transducers: a sensor with histidine kinase (hk), a response regulator containing a phospho-accepting receiver (rr), and a histidine-containing phosphotransmitter (hpt). in this study, we examined hk expression using a green fluorescent protein (gfp) reporter driven by hk promoters in aspergillus nidulans. all the transformants showed fluoresc ...200818256501
sumoylation in aspergillus nidulans: sumo inactivation, overexpression and live-cell imaging.sumoylation, the reversible covalent attachment of small ubiquitin-like modifier (sumo) peptides has emerged as an important regulator of target protein function. in saccharomyces cerevisiae, but not in schizosaccharyomes pombe, deletion of the gene encoding sumo peptides is lethal. we have characterized the sumo-encoding gene, sumo, in the filamentous fungus aspergillus nidulans. the sumo gene was deleted in a diploid and sumodelta haploids were recovered. the mutant was viable but exhibited im ...200818262811
cloning and sequence characterization of a non-reducing polyketide synthase gene from the lichen xanthoparmelia semiviridis.lichens produce a diverse array of secondary metabolites that have shown various biological activities. of particular interest are the coupled phenolics that originate from polyketide pathways, such as depsides, depsidones and usnic acids, which are produced almost solely by lichens. based on the presumed catalytic domains required for the synthesis of the key intermediates beta-orsellinic acid and methylphloroacetophenone, two pairs of degenerate primers were designed to target specifically the ...200818280724
a defect of ligd (human lig4 homolog) for nonhomologous end joining significantly improves efficiency of gene-targeting in aspergillus oryzae.gene-targeting by homologous recombination occurs rarely during transformation since nonhomologous recombination is predominant in aspergillus oryzae. to develop a highly efficient gene-targeting system for a. oryzae, we constructed disrupted strains harboring a gene (ligd) encoding human dna ligase iv homolog that is involved in the final step of dna nonhomologous end joining. the a. oryzae ligd disruptants showed no apparent defect in vegetative growth and/or conidiation, and exhibited increas ...200818282727
functional and physical interaction of blue- and red-light sensors in aspergillus nidulans.light sensing is very important for organisms in all biological kingdoms to adapt to changing environmental conditions. it was discovered recently that plant-like phytochrome is involved in light sensing in the filamentous fungus aspergillus nidulans[1]. here, we show that phytochrome (fpha) is part of a protein complex containing lrea (wc-1) and lreb (wc-2) [2, 3], two central components of the neurospora crassa blue-light-sensing system. we found that fpha represses sexual development and myco ...200818291652
nucleosome positioning and histone h3 acetylation are independent processes in the aspergillus nidulans prnd-prnb bidirectional promoter.in aspergillus nidulans, proline can be used as a carbon and nitrogen source, and its metabolism requires the integration of three signals, including proline induction and nitrogen and carbon metabolite derepression. we have previously shown that the bidirectional promoter in the prnd-prnb intergenic region undergoes drastic chromatin rearrangements such that proline induction leads to the loss of positioned nucleosomes, whereas simultaneous carbon and nitrogen metabolite repression results in t ...200818296621
efficacy of female culex quinquefasciatus with entomopathogenic fungus fusarium pallidoroseum.this study was conducted to isolate and identify natural entomopathogenic fungi from female culex quinquefasciatus and to test their adulticidal activity. field-collected female c. quinquefasciatus died early and were placed on a saboraud's dextrose agar plates for growth and isolation of natural entomopathogenic fungi. the plates were maintained in an incubator at 24+/-2 degrees c for 3 days. four fungal species were isolated in two genera namely, aspergillus and fusarium. the identified fungal ...200818327611
characterization of an acyl-coa: carboxylate coa-transferase from aspergillus nidulans involved in propionyl-coa detoxification.filamentous fungi metabolize toxic propionyl-coa via the methylcitrate cycle. disruption of the methylcitrate synthase gene leads to an accumulation of propionyl-coa and attenuates virulence of aspergillus fumigatus. however, addition of acetate, but not ethanol, to propionate-containing medium strongly reduces the accumulation of propionyl-coa and restores growth of the methylcitrate synthase mutant. therefore, the existence of a coa-transferase was postulated, which transfers the coash moiety ...200818331473
the role of actin, fimbrin and endocytosis in growth of hyphae in aspergillus nidulans.filamentous fungi are ideal systems to study the process of polarized growth, as their life cycle is dominated by hyphal growth exclusively at the cell apex. the actin cytoskeleton plays an important role in this growth. until now, there have been no tools to visualize actin or the actin-binding protein fimbrin in live cells of a filamentous fungus. we investigated the roles of actin (acta) and fimbrin (fima) in hyphal growth in aspergillus nidulans. we examined the localization of acta::gfp and ...200818331474
a trispecies aspergillus microarray: comparative transcriptomics of three aspergillus species.the full-genome sequencing of the filamentous fungi aspergillus nidulans, aspergillus niger, and aspergillus oryzae has opened possibilities for studying the cellular physiology of these fungi on a systemic level. as a tool to explore this, we are making available an affymetrix genechip developed for transcriptome analysis of any of the three above-mentioned aspergilli. transcriptome analysis of triplicate batch cultivations of all three aspergilli on glucose and xylose media was used to validat ...200818332432
characterization of fusarium graminearum mes1 reveals roles in cell-surface organization and virulence.the surfaces of fungal hyphae are mosaics of carbohydrates and cell-surface proteins. presently, very little is known about the role of these proteins and their organization at the cell surface. here, we characterize two fusarium graminearum genes implicated in cell-surface organization, mes1 (fgsg_06680) and pls1 (fgsg_08695). mes1 is a homologue of mesa, which is required for the formation of stable polarity axes in aspergillus nidulans. pls1 encodes a tetraspanin, which belongs to a class of ...200818339563
norsolorinic acid from aspergillus nidulans inhibits the proliferation of human breast adenocarcinoma mcf-7 cells via fas-mediated pathway.norsolorinic acid, isolated from the aspergillus nidulans, was investigated for its antiproliferative activity in human breast adenocarcinoma mcf-7 cells. to identity the anticancer mechanism of norsolorinic acid, we assayed its effect on apoptosis, cell cycle distribution, and levels of p53, p21/waf1, fas/apo-1 receptor and fas ligand. the results showed that norsolorinic acid induced apoptosis of mcf-7 cells without mediation of p53 and p21/waf1. we suggest that fas/fas ligand apoptotic system ...200818346044
aspergillus nidulans natural product biosynthesis is regulated by mpkb, a putative pheromone response mitogen-activated protein kinase.the aspergillus nidulans putative mitogen-activated protein kinase encoded by mpkb has a role in natural product biosynthesis. an mpkb mutant exhibited a decrease in sterigmatocystin gene expression and low mycotoxin levels. the mutation also affected the expression of genes involved in penicillin and terrequinone a synthesis. mpkb was necessary for normal expression of laea, which has been found to regulate secondary metabolism gene clusters.200818378656
screening of aspergillus species for occurrence of lectins and their characterization.ten species of aspergillus were screened for occurrence of lectins. each of the species was investigated for the occurrence of extracellular, surface-bound and intracellular lectin activities. as many as four species namely, aspergillus niger, aspergillus versicolor, aspergillus rugulosus and aspergillus nidulans, were found to possess intracellular lectin activities, while none of the species showed extracellular or surface-bound lectin activities. each of the lectin was characterized with resp ...200818383222
influence of farnesol on the morphogenesis of aspergillus niger.farnesol was the first quorum-sensing regulator to be found in eukaryotic cells. in candida albicans, a dimorphic fungal human pathogen, farnesol blocks the yeast-to-filamentous growth transition. here we show that in aspergillus niger farnesol acts as an inhibitor of conidiation: colonies grown on media containing farnesol were unable to develop conidia. although farnesol treated a. niger cultures exhibited a colony morphology resembling the "fluffy" phenotype of a. nidulans, which is caused by ...200818383232
the aspergillus nidulans fcyb cytosine-purine scavenger is highly expressed during germination and in reproductive compartments and is downregulated by endocytosis.we cloned and characterized an aspergillus nidulans gene, called fcyb, encoding the closest homologue to the yeast fcy2p/fcy21p permeases. deletion of fcyb (deltafcyb) does not affect growth, development, reproduction or bulk purine uptake, but eliminates the leaky growth on purines of deltaazgadeltauapcdeltauapa strains, lacking all known purine transporters, and confers resistance to the antifungal 5-fluorocytosine. kinetic analyses showed fcyb is a low-capacity, high-affinity, cytosine-purine ...200818384518
quantifying metabolic activity of filamentous fungi using a colorimetric xtt assay.the filamentous nature and robust cell walls of many fungi render traditional measurements of active biomass (e.g., turbidity, dry cell weight) ineffective for most fungal bioprocesses. to overcome this challenge, an assay for quantification of overall metabolic activity is developed using 2,3-bis(2-methoxy-4-nitro-5-sulfophenly)-5-[(phenylamino) carbonyl]-2h-tetrazolium hydroxide (xtt), which in the presence of active mitochondria is converted to a water-soluble formazan derivative that absorbs ...200818386938
the nuclear migration protein nudf/lis1 forms a complex with nudc and bnfa at spindle pole bodies.nuclear migration depends on microtubules, the dynein motor complex, and regulatory components like lis1 and nudc. we sought to identify new binding partners of the fungal lis1 homolog nudf to clarify its function in dynein regulation. we therefore analyzed the association between nudf and nudc in aspergillus nidulans. nudf and nudc directly interacted in yeast two-hybrid experiments via nudf's wd40 domain. nudc-green fluorescent protein (nudc-gfp) was localized to immobile dots in the cytoplasm ...200818390647
polarized growth in fungi--interplay between the cytoskeleton, positional markers and membrane domains.one kind of the most extremely polarized cells in nature are the indefinitely growing hyphae of filamentous fungi. a continuous flow of secretion vesicles from the hyphal cell body to the growing hyphal tip is essential for cell wall and membrane extension. because microtubules (mt) and actin, together with their corresponding motor proteins, are involved in the process, the arrangement of the cytoskeleton is a crucial step to establish and maintain polarity. in saccharomyces cerevisiae and schi ...200818399939
analysis of aspergillus nidulans metabolism at the genome-scale.aspergillus nidulans is a member of a diverse group of filamentous fungi, sharing many of the properties of its close relatives with significance in the fields of medicine, agriculture and industry. furthermore, a. nidulans has been a classical model organism for studies of development biology and gene regulation, and thus it has become one of the best-characterized filamentous fungi. it was the first aspergillus species to have its genome sequenced, and automated gene prediction tools predicted ...200818405346
egld, a putative endoglucanase, with an expansin like domain is localized in the conidial cell wall of aspergillus nidulans.although the process of conidial germination in filamentous fungi has been extensively studied, many aspects remain to be elucidated since the asexual spore or conidium is vital in their life cycle. breakage and reformation of cell wall polymer bonds along with the maintenance of cell wall plasticity during conidia germination depend upon a range of hydrolytic enzymes whose activity is analogous to that of expansins, a highly conserved group of plant cell wall proteins with characteristic wall l ...200818406638
arp11 affects dynein-dynactin interaction and is essential for dynein function in aspergillus nidulans.the dynactin complex contains proteins including p150 that interacts with cytoplasmic dynein and an actin-related protein arp1 that forms a minifilament. proteins including arp11 and p62 locate at the pointed end of the arp1 filament, but their biochemical functions are unclear (schroer ta. dynactin. annu rev cell dev biol 2004;20:759-779). in aspergillus nidulans, loss of arp11 or p62 causes the same nuclear distribution (nud) defect displayed by dynein mutants, indicating that these pointed-en ...200818410488
identification and evolution of fungal mitochondrial tyrosyl-trna synthetases with group i intron splicing activity.the bifunctional neurospora crassa mitochondrial tyrosyl-trna synthetase (cyt-18 protein) both aminoacylates mitochondrial trna(tyr) and acts as a structure-stabilizing splicing cofactor for group i introns. previous studies showed that cyt-18 has distinct trna(tyr) and group i intron-binding sites, with the latter formed by three small "insertions" in the nucleotide-binding fold and other structural adaptations compared with nonsplicing bacterial tyrosyl-trna synthetases. here, analysis of geno ...200818413600
functional equivalence of translation factor eif5b from candida albicans and saccharomyces cerevisiae.eukaryotic translation initiation factor 5b (eif5b) plays a role in recognition of the aug codon in conjunction with translation factor eif2, and promotes joining of the 60s ribosomal subunit. to see whether the eif5b proteins of other organisms function in saccharomyces cerevisiae, we cloned the corresponding genes from oryza sativa, arabidopsis thaliana, aspergillus nidulans and candida albican and expressed them under the control of the galactose-inducible gal promoter in the fun12delta strai ...200818414002
crea mediates repression of the regulatory gene xlnr which controls the production of xylanolytic enzymes in aspergillus nidulans.the aspergillus nidulans xlnr gene encodes a zn(2)cys(6) transcription activator necessary for the synthesis of the main xylanolytic enzymes, i.e. endo-xylanases x(22), x(24) and x(34), and beta-xilosidase xlnd. expression of xlnr is not sufficient for induction of genes encoding the xylanolytic complex, the presence of xylose is absolutely required. it has been established previously that the wide-domain carbon catabolite repressor crea indirectly represses xlna (encodes x(22)) and xlnb (encode ...200818420433
aspergillus nidulans chia is a glycosylphosphatidylinositol (gpi)-anchored chitinase specifically localized at polarized growth sites.it is believed that chitinases play important physiological roles in filamentous fungi since chitin is one of the major cell wall components in these organisms. in this paper we investigated a chitinase gene, chia, of aspergillus nidulans and found that the gene product of chia consists of a signal sequence, a region including chitinase consensus motifs, a ser/thr/pro-rich region and a glycosylphosphatidylinositol (gpi)-anchor attachment motif. phosphatidylinositol-specific phospholipase c treat ...200818420434
[molecular mechanism of lissencephaly--how lis1 and ndel1 regulate cytoplasmic dynein?].lissencephaly is a devastating neurological disorder characterized by smooth cerebral surface, thick cortex and dilated lateral ventricules due to defective neuronal migration. lis1 was identified as a mutated gene in classical lissencephaly patients, and turned out to be a beta-subunit of platelet activating factor acetylhydrolase. studies in model organisms, particularly aspergillus nidulans, as well as those in the mouse, have uncovered an evolutionarily conserved pathway that involves lis1 a ...200818421979
localization and function of adp ribosylation factor a in aspergillus nidulans.filamentous fungi undergo polarized hyphal growth throughout the majority of their life cycle. the spitzenkörper is a structure unique to filamentous fungi that participates in hyphal growth and is composed largely of vesicles. an important class of proteins involved in vesicle assembly and trafficking are the adp-ribosylation factors (arfs). in saccharomyces cerevisiae, arf1p and arf2p are involved in secretion. aspergillus nidulans arfa is a homolog of scarf1p and scarf2p with 75% of amino aci ...200818430001
ndel1 promotes axon regeneration via intermediate filaments.failure of axons to regenerate following acute or chronic neuronal injury is attributed to both the inhibitory glial environment and deficient intrinsic ability to re-grow. however, the underlying mechanisms of the latter remain unclear. in this study, we have investigated the role of the mammalian homologue of aspergillus nidulans nude, ndel1, emergently viewed as an integrator of the cytoskeleton, in axon regeneration. ndel1 was synthesized de novo and upregulated in crushed and transected sci ...200818431495
the unprocessed preprotein form iatc103s of the isopenicillin n acyltransferase is transported inside peroxisomes and regulates its self-processing.previous studies in penicillium chrysogenum and aspergillus nidulans suggested that self-processing of the isopenicillin n acyltransferase (iat) is an important differential factor in these fungi. expression of a mutant pende(c103s) gene in p. chrysogenum gave rise to an unprocessed inactive variant of iat (iat(c103s)) located inside peroxisomes, which indicates that transport of the proiat inside these organelles is not dependent on the processing state of the protein. co-expression of the pend ...200818439860
characterization of a highly active promoter, pbbgpd, in beauveria bassiana.the promoter of glyceraldehyde-3-phosphate dehydrogenase (gpd) gene from aspergillus nidulans (pgpda) is widely used to direct expression of target genes constitutively in fungi. however, in some species, a heterogeneous promoter is found to be of low efficiency. to obtain a high-efficiency promoter for transformation of beauveria bassiana, an entomopathogenic fungus widely used as an mycoinsecticide, a glyceraldehyde-3-phosphate dehydrogenase gene (bbgpd) promoter, was cloned and characterized. ...200818443858
rapid tip-directed movement of golgi equivalents in growing aspergillus nidulans hyphae suggests a mechanism for delivery of growth-related materials.golgi equivalents (ges) process materials in the fungal secretory pathway. despite the importance of localized secretion in fungal tip growth, ge behaviour in living hyphae has not been documented. the distribution was monitored of an aspergillus nidulans putative ge-associated protein, copa, tagged with gfp (copa-gfp). this co-localized with a golgi body/ge marker established in other systems, alpha-2,6-sialyltransferase, tagged with red fluorescent protein (st-rfp). copa-gfp and st-rfp distrib ...200818451063
crystal structure of a new type of nadph-dependent quinone oxidoreductase (qor2) from escherichia coli.escherichia coli qor2 [nad(p)h-dependent quinone oxidoreductase; a ytfg gene product], which catalyzes two-electron reduction of methyl-1,4-benzoquinone, is a new type of quinone-reducing enzyme with distinct primary sequence and oligomeric conformation from previously known quinone oxidoreductases. the crystal structures of native qor2 and the qor2-nadph (nicotinamide adenine dinucleotide phosphate, reduced form) complex reveal that qor2 consists of two domains (n-domain and c-domain) resemblin ...200818455185
ambient ph gene regulation in fungi: making connections.many fungi grow over a wide ph range and their gene expression is tailored to the environmental ph. in aspergillus nidulans, the transcription factor pacc, an activator of genes expressed in alkaline conditions and a repressor of those expressed in acidic conditions, undergoes two processing proteolyses, the first being ph-signal dependent and the second proteasomal. signal transduction involves a 'go-between' connecting two complexes, one of which comprises two plasma membrane proteins and an a ...200818457952
the vea regulatory system and its role in morphological and chemical development in fungi.in fungi, the velvet gene, or vea, is involved in the regulation of diverse cellular processes, including control of asexual and sexual development as well as secondary metabolism. this global regulator is conserved in numerous fungal species. interestingly, in aspergilli, where most of the studies on vea have been carried out, this gene has been described to mediate development in response to light. in recent years the knowledge of this important regulatory system has expanded through the use o ...200818457967
two zinc finger transcription factors, crza and slta, are involved in cation homoeostasis and detoxification in aspergillus nidulans.to investigate cation adaptation and homoeostasis in aspergillus nidulans, two transcription-factor-encoding genes have been characterized. the a. nidulans orthologue crza of the saccharomyces cerevisiae crz1 gene, encoding a transcription factor mediating gene regulation by ca(2+), has been identified and deleted. the crza deletion phenotype includes extreme sensitivity to alkaline ph, ca(2+) toxicity and aberrant morphology connected with alterations of cell-wall-related phenotypes such as red ...200818471095
a single acyl-coa dehydrogenase is required for catabolism of isoleucine, valine and short-chain fatty acids in aspergillus nidulans.an acyl-coa dehydrogenase has been identified as part of the mitochondrial beta-oxidation pathway in the ascomycete fungus aspergillus nidulans. disruption of the scda gene prevented use of butyric acid (c(4)) and hexanoic acid (c(6)) as carbon sources and reduced cellular butyryl-coa dehydrogenase activity by 7.5-fold. while the mutant strain exhibited wild-type levels of growth on erucic acid (c(22:1)) and oleic acid (c(18:1)), some reduction in growth was observed with myristic acid (c(14)). ...200817656140
the aspergillus nidulans ceta and cala genes are involved in conidial germination and cell wall morphogenesis.the aspergillus nidulans genes ceta (an3079.2) and cala (an7619.2) encode a novel class of fungal thaumatin-like proteins of unknown function. deletion of ceta does not result in an observable phenotype [greenstein, s., shadkchan, y., jadoun, j., sharon, c., markovich, s., osherov, n., 2006. analysis of the aspergillus nidulans thaumatin-like ceta gene and evidence for transcriptional repression of pyr4 expression in the ceta-disrupted strain. fungal genet. biol. 43, 42-53]. we prepared knockout ...200817703972
transient disruption of non-homologous end-joining facilitates targeted genome manipulations in the filamentous fungus aspergillus nidulans.we have developed a transiently disrupted nkua system in aspergillus nidulans for efficient gene targeting. the nkua disruption was made by inserting a counter-selectable marker flanked by a direct repeat (dr) composed of nkua sequences. in the disrupted state, the non-homologous end-joining (nhej) activity is abolished and gene targeting can be performed with success rates identical to those obtained with permanent nkua knock-out strains. when gene targeting is complete, the functional nkua all ...200817703973
neurospora crassa ve-1 affects asexual conidiation.the velvet factor of the homothallic fungus aspergillus nidulans promotes sexual fruiting body formation. the encoding vea gene is conserved among fungi, including the ascomycete neurospora crassa. there, the orthologous ve-1 gene encodes a deduced protein with high similarity to a. nidulans vea. cross-complementation experiments suggest that both the promoter and the coding sequence of n. crassa ve-1 are functional to complement the phenotype of an a. nidulans deletion mutant. moreover, ve-1 ex ...200817631397
napa and napb are the aspergillus nidulans nap/set family members and napb is a nuclear protein specifically interacting with importin alpha.in eukaryotic cells, importin alpha is the major carrier for transport protein cargoes into the nucleus. we characterize here kapa, the single aspergillus nidulans gene encoding an importin alpha. using an affinity approach, we identify six potential interactors of kapa(50), a deleted version of kapa lacking the autoinhibitory importin-beta-binding domain. one such interactor is napb, the a. nidulans orthologue of saccharomyces cerevisiae vps75p, a histone chaperone member of the nap/set family ...200817890114
evaluation of thermophilic fungal consortium for paddy straw composting.out of 10 thermophilic fungi isolated from wheat straw, farm yard manure, and soil, only three showed highest cellobiase, carboxymethyl cellulase, xylanase, and fpase activities. they were identified as aspergillus nidulans (th(4)), scytalidium thermophilum (th(5)), and humicola sp. (th(10)). a fungal consortium of these three fungi was used to compost a mixture (1:1) of silica rich paddy straw and lignin rich soybean trash. the composting of paddy straw for 3 months, during summer period in nor ...200817874191
characterization and kinetics of the major purine transporters in aspergillus fumigatus.three genes encoding putative purine transporters have been identified in silico in the genome of aspergillus fumigatus by their very close similarity of their translation products to well-studied homologues in a. nidulans. two of these transporters, called afuapc and afazga, were found responsible for bulk uptake of purines and studied in detail herein. genetic knock-out analysis, regulation of transcription, direct purine uptake assays and heterologous expression in a. nidulans have unequivoca ...200817881254
the penicillium chrysogenum antifungal protein paf, a promising tool for the development of new antifungal therapies and fungal cell biology studies.in recent years the interest in antimicrobial proteins and peptides and their mode of action has been rapidly increasing due to their potential to prevent and combat microbial infections in all areas of life. a detailed knowledge about the function of such proteins is the most important requirement to consider them for future application. our research in recent years has been focused on the low molecular weight, cysteine-rich and cationic antifungal protein paf from penicillium chrysogenum, whic ...200817965829
transcriptional regulation of genes on the non-syntenic blocks of aspergillus oryzae and its functional relationship to solid-state cultivation.transcriptome analysis revealed close relationship between solid-state cultivation and the transcriptional regulation of the genes on the non-syntenic blocks (nsbs), which were characterized by the comparison of aspergillus oryzae genome with those of aspergillus fumigatus and aspergillus nidulans. average expression ratio of the genes on nsbs in solid-state cultivation was significantly higher than that on the syntenic blocks (sbs). of the induced genes, the genes relating to metabolism, which ...200817967552
isolation of four pepsin-like protease genes from aspergillus niger and analysis of the effect of disruptions on heterologous laccase expression.four new aspartic protease genes pepaa, pepab, pepac and pepad from aspergillus niger were identified using a comparative genomic approach. all four gene products have highly conserved attributes that are characteristic of aspartic proteases; however, each one has novel sequence features. the pepaa protease appears to represent an ortholog of a pepsin-type aspartic protease previously identified from talaromyces emersonii and scleotinia sclerotiorum. the pepab protease appears to be an ortholog ...200817977034
the aspergillus nidulans esdc (early sexual development) gene is necessary for sexual development and is controlled by vea and a heterotrimeric g protein.the esdc (early sexual development) gene was isolated by using an expressed sequence tag (est) as a probe from a genomic library of the early sexual developmental stage mycelia of aspergillus nidulans. the sequence analysis revealed that the esdc gene contains a 59bp intron and encodes a 266 amino acid polypeptide with a calculated molecular weight of 29.4kda. the esdc protein is conserved among filamentous fungi and has a domain with similarity to a glycogen binding domain conserved in the beta ...200817977758
the neurospora crassa uvs-3 epistasis group encodes homologues of the atr/atrip checkpoint control system.the mutagen sensitive uvs-3 and mus-9 mutants of neurospora show mutagen and hydroxyurea sensitivity, mutator effects and duplication instability typical of recombination repair and dna damage checkpoint defective mutants. to determine the nature of these genes we used cosmids from a genomic library to clone the uvs-3 gene by complementation for mms sensitivity. mutation induction by transposon insertion and rip defined the coding sequence. rflp analysis confirmed that this sequence maps in the ...200817983847
the nada gene of aspergillus nidulans, encoding adenine deaminase, is subject to a unique regulatory pattern.the adenine deaminase of a. nidulans, encoded by nada, can be considered both as a catabolic and a purine salvage enzyme. we show that its transcriptional regulation reflects this double metabolic role. as all other genes involved in purine utilisation it is induced by uric acid, and this induction is mediated by the uay transcription factor. however, it is also independently and synergistically induced by adenosine by a uay-independent mechanism. at variance with all other enzymes of purine cat ...200818055231
functional characterization of the putative aspergillus nidulans dna damage binding protein homologue ddba.nucleotide excision repair (ner) eliminates helix-distorting dna base lesions. seven xp-deficient genetic complementation groups (xpa to xpg) have already been identified in mammals, and their corresponding genes have been cloned. hereditary defects in ner are associated with several diseases, including xeroderma pigmentosum (xp). uv-ddb (xpe) is formed by two associated subunits, ddb1 and ddb2. uv-ddb was identified biochemically as a protein factor that exhibits very strong and specific bindin ...200818060432
an eleven amino acid residue deletion expands the substrate specificity of acetyl xylan esterase ii (axe ii) from penicillium purpurogenum.the soft-rot fungus penicillium purpurogenum secretes to the culture medium a variety of enzymes related to xylan biodegradation, among them three acetyl xylan esterases (axe i, ii and iii). axe ii has 207 amino acids; it belongs to family 5 of the carbohydrate esterases and its structure has been determined by x-ray crystallography at 0.9 a resolution (pdb 1g66). the enzyme possesses the alpha/beta hydrolase fold and the catalytic triad typical of serine esterases (ser90, his187 and asp175). ax ...200818060506
crea-mediated repression in aspergillus nidulans does not require transcriptional auto-regulation, regulated intracellular localisation or degradation of crea.the major regulatory protein in carbon repression in aspergillus nidulans is crea. strains constitutively over-expressing crea show normal responses to carbon repression, indicating that auto-regulation of crea is not essential for crea-mediated regulation. in these strains, high levels of crea are present whether cells are grown in repressing or derepressing conditions, indicating large-scale degradation of crea does not play a key role. crea is located in the nucleus and cytoplasm in cells whe ...200818063396
aspergillus mycoviruses are targets and suppressors of rna silencing.rna silencing can function as a virus defense mechanism in a diverse range of eukaryotes, and many viruses are capable of suppressing the silencing machinery targeting them. however, the extent to which this occurs between fungal rna silencing and mycoviruses is unclear. here, three aspergillus dsrna mycoviruses were partially characterized, and their relationship to rna silencing was investigated. aspergillus virus 1816 is related to agaricus bisporus white button mushroom virus 1 and suppresse ...200818065651
rna silencing gene truncation in the filamentous fungus aspergillus nidulans.the genus aspergillus is ideally suited for the investigation of rna silencing evolution because it includes species that have experienced a variety of rna silencing gene changes. our work on this subject begins here with the model species aspergillus nidulans. filamentous ascomycete fungi generally each encode two of the core rna silencing proteins, dicer and argonaute, but a. nidulans appears to have lost one of each to gene truncation events. although a role in growth, development, or rna sil ...200818065653
preferential localization of the endocytic internalization machinery to hyphal tips underlies polarization of the actin cytoskeleton in aspergillus nidulans.abpa, slab and ampa, three demonstrated components of the endocytic internalization machinery, are strongly polarized in aspergillus nidulans hyphae, forming a ring that embraces the hyphal tip, leaving an area of exclusion at the apex. abpa, a prototypic endocytic internalization marker, localizes to highly motile and transient (average half life, 24 +/- 5 s) peripheral punctate structures overlapping with actin patches, which also predominate in the tip. slab also localizes to peripheral patch ...200818179595
reciprocal oxylipin-mediated cross-talk in the aspergillus-seed pathosystem.in aspergilli, mycotoxin production and sporulation are governed, in part, by endogenous oxylipins (oxygenated, polyunsaturated fatty acids and metabolites derived therefrom). in aspergillus nidulans, oxylipins are synthesized by the dioxygenase enzymes ppoa, ppob and ppoc. structurally similar oxylipins are synthesized in seeds via the action of lipoxygenase (lox) enzymes. previous reports have shown that exogenous application of seed oxylipins to aspergillus cultures alters sporulation and myc ...200818181962
implication of a regulator of g protein signalling (bbrgs1) in conidiation and conidial thermotolerance of the insect pathogenic fungus beauveria bassiana.beauveria bassiana is an insect pathogenic fungus widely used as a biocontrol agent to infect and control insect pests. the conidium initiates pathogenesis and mediates disease transmission, however, little is known about genetic elements that control conidiation. here, the cloning and characterization of a regulatory g protein-signalling (rgs) gene bbrgs1 from b. bassiana is reported. phylogenetic analysis showed that bbrgs1 was orthologous to the rgs protein, flba from aspergillus nidulans. th ...200818201190
inhibition of fusarium graminearum growth and development by farnesol.the isoprenoid farnesol was previously shown to induce morphological features characteristic of apoptosis in the filamentous fungus aspergillus nidulans. this study demonstrates that under similar liquid media growth conditions, farnesol also triggers apoptosis in the plant pathogenic fungus fusarium graminearum. however, unlike a. nidulans, f. graminearum spores treated with farnesol exhibited altered germination patterns and most (>60%) lysed upon prolonged exposure. given the economic importa ...200818201191
the tip growth apparatus of aspergillus nidulans.hyphal tip growth in fungi is important because of the economic and medical importance of fungi, and because it may be a useful model for polarized growth in other organisms. we have investigated the central questions of the roles of cytoskeletal elements and of the precise sites of exocytosis and endocytosis at the growing hyphal tip by using the model fungus aspergillus nidulans. time-lapse imaging of fluorescent fusion proteins reveals a remarkably dynamic, but highly structured, tip growth a ...200818216285
purification and biochemical characterization of a broad substrate specificity thermostable alkaline protease from aspergillus nidulans.aspergillus nidulans pw1 produces an extracellular carboxylesterase activity that acts on several lipid esters when cultured in liquid media containing olive oil as a carbon source. the enzyme was purified by gel filtration and ion exchange chromatography. it has an apparent mw and pi of 37 kda and 4.5, respectively. the enzyme efficiently hydrolyzed all assayed glycerides, but showed preference toward short- and medium-length chain fatty acid esters. maximum activity was obtained at ph 8.5 at 4 ...200818224318
identification of biomarkers for genotyping aspergilli using non-linear methods for clustering and classification.in the present investigation, we have used an exhaustive metabolite profiling approach to search for biomarkers in recombinant aspergillus nidulans (mutants that produce the 6- methyl salicylic acid polyketide molecule) for application in metabolic engineering.200818226195
functional analyses of heterotrimeric g protein g alpha and g beta subunits in gibberella zeae.the homothallic ascomycete fungus gibberella zeae (anamorph: fusarium graminearum) is a major toxigenic plant pathogen that causes head blight disease on small-grain cereals. the fungus produces the mycotoxins deoxynivalenol (don) and zearalenone (zea) in infected hosts, posing a threat to human and animal health. despite its agricultural and toxicological importance, the molecular mechanisms underlying its growth, development and virulence remain largely unknown. to better understand such mecha ...200818227243
characterisation of aspergillus nidulans polarisome component bema.bema, the orthologue of saccharomyces cerevisiae bem1p, was identified through genome sequence comparison. we have shown that it plays a similar role to bem1p in yeast, acting as a cell growth protein. deletion of the gene produced a moderately abnormal hyphal tip morphology, and had an extremely detrimental effect on conidiospore production, with development stalling after conidiophore vesicle production. it was also shown that bema is required for vacuole fusion, similar to bem1p. this role is ...200818234530
ambient ph signaling regulates expression of the serine protease gene (spr1) in pine wilt nematode-trapping fungus, monacrosporium megalosporum.we have cloned and characterized spr1, a putative serine protease gene, from a nematode-trapping fungus, monacrosporium megalosporum. the gene was present as a single copy in the genome. the predicted protein sequence of spr1 is homologous to the putative cuticle-degrading serine proteases pii and azo1 from the nematode-trapping fungus, arthrobotrys oligospora. in the 5' untranslated region near the initiation codon, consensus sequences to an area binding site, a well-known mediator of nitrogen ...200816697631
rapd typing of aspergillus chevalieri, aspergillus nidulans, aspergillus tetrazonus (quadrilineatus) and their teleomorphs using 5'-d[aacgcgcaac]-3' and 5'-d[cccgtcagca]-3' primers.sexuality in fungi has long been a matter of concerns and debates that always necessitated extensive analysis of the relationship between organisms assumed to represent different developmental forms of the same organism. moreover, mating-virulence correlation and the growing worry of opportunistic fungal infections in immunocompromised states associated with aids, cancer chemotherapy and organ transplantation protocols have been critically addressed nowadays. in view of that, we genetically char ...200817268891
a new protein carrying an nmra-like domain is required for cell differentiation and development in dictyostelium discoideum.we have isolated a dictyostelium mutant unable to induce expression of the prestalk-specific marker ecmb in monolayer assays. the disrupted gene, pada, leads to a range of phenotypic defects in growth and development. we show that pada is essential for growth, and we have generated a thermosensitive mutant allele, pada(-). at the permissive temperature, mutant cells grow poorly; they remain longer at the slug stage during development and are defective in terminal differentiation. at the restrict ...200818638468
the pot and plob vector systems: improving ease of transgene expression in botrytis cinerea.this paper outlines the construction of a novel vector system comprising interchangeable terminators, as well as a multiple cloning site (mcs), to facilitate the transformation of the fungal plant pathogen botrytis cinerea. previous molecular studies on b. cinerea have relied upon the plob1 based vector system (controlled by the aspergillus nidulans olic promoter and a region reported to be the b. cinerea tuba terminator). investigations, however, have revealed that, rather than the genuine b. c ...200819164879
systems analysis unfolds the relationship between the phosphoketolase pathway and growth in aspergillus nidulans.aspergillus nidulans is an important model organism for studies on fundamental eukaryotic cell biology and on industrial processes due to its close relation to a. niger and a. oryzae. here we identified the gene coding for a novel metabolic pathway in a. nidulans, namely the phosphoketolase pathway, and investigated the role of an increased phosphoketolase activity.200819052639
restoration of electron transport without proton pumping in mammalian mitochondria.we have restored the coq oxidative capacity of mouse mtdna-less cells (rho degrees cells) by transforming them with the alternative oxidase aox of emericella nidulans. cotransforming rho degrees cells with the nadh dehydrogenase of saccharomyces cerevisiae, ndi1 and aox recovered the nadh dh/coq reductase and the coq oxidase activities. coq oxidation by aox reduces the dependence of rho degrees cells on pyruvate and uridine. coexpression of aox and ndi1 further improves the recycling of nad(+). ...200819020091
functional analysis of c2h2 zinc finger transcription factor crza involved in calcium signaling in aspergillus nidulans.calcium signaling systems are widely employed in eukaryotes and are implicated in the regulation of diverse biological processes. calcineurin is an important signaling component, which mediates ion homeostasis and virulence in several fungi. based on intensive studies conducted on budding yeast, transcription factor crz1p is thought to be a target of calcineurin. to provide insight into calcium signaling, a crz1p homolog (crza) in a filamentous fungus aspergillus nidulans was identified and its ...200819002465
regulation of autolysis in aspergillus nidulans.in terms of cell physiology, autolysis is the centerpiece of carbon-starving fungal cultures. in the filamentous fungus model organism aspergillus nidulans, the last step of carbon-starvation-triggered autolysis was the degradation of the cell wall of empty hyphae, and this process was independent of concomitantly progressing cell death at the level of regulation. autolysis-related proteinase and chitinase activities were induced via flug signaling, which initiates sporulation and inhibits veget ...200818975147
identification and characterization of the asperthecin gene cluster of aspergillus nidulans.the sequencing of aspergillus genomes has revealed that the products of a large number of secondary metabolism pathways have not yet been identified. this is probably because many secondary metabolite gene clusters are not expressed under normal laboratory culture conditions. it is, therefore, important to discover conditions or regulatory factors that can induce the expression of these genes. we report that the deletion of sumo, the gene that encodes the small ubiquitin-like protein sumo in a. ...200818978088
identification of the novel penicillin biosynthesis gene aatb of aspergillus nidulans and its putative evolutionary relationship to this fungal secondary metabolism gene cluster.the final step of penicillin biosynthesis in the filamentous fungus aspergillus nidulans is catalysed by isopenicillin n acyltransferase encoded by the aata gene. because there is no bacterial homologue, its evolutionary origin remained obscure. as shown here,disruption of aata still enabled penicillin production. genome mining led to the discovery of the aatb gene(an6775.3) which has a similar structure and expression pattern as aata. disruption of aatb resulted in a reduced penicillin titre. s ...200818942174
identification of genes differentially expressed in a strain of the mold aspergillus nidulans carrying a loss-of-function mutation in the pala gene.to identify genes differentially expressed in a strain of the mold aspergillus nidulans carrying a loss-of-function mutation in pala, a gene in the ph-responsive signal transduction pathway, suppression subtractive hybridization was performed between rna isolated from the bia1 and bia1 pala1 strains grown under limiting inorganic phosphate at ph 5.0. we have identified several genes upregulated in the bia1 pala1 mutant strain that play important roles in mitotic fidelity, stress responses, enzym ...200818923548
characterization of the aspergillus niger prtt, a unique regulator of extracellular protease encoding genes.expression of several aspergillus niger genes encoding major secreted, but not vacuolar, protease genes including the major acid protease gene pepa, was shown to be affected in the previously isolated a. niger protease mutant, ab1.13 [mattern, i.e., van noort, j.m., van den berg, p., archer, d.a., roberts, i.n., hondel, c.a.m.j.j., 1992. isolation and characterization of mutants of aspergillus niger deficient in extracellular proteases. molecular & general genetics 2, 332-336]. complementation c ...200818930158
copy number suppressors of the aspergillus nidulans nima1 mitotic kinase display distinctive and highly dynamic cell cycle-regulated locations.the aspergillus nidulans nima kinase is essential for mitosis and is the founding member of the conserved nima-related kinase (nek) family of protein kinases. to gain insight into nima function, a copy number suppression screen has been completed that defines three proteins termed mcna, mcnb, and mcnc (multi-copy-number suppressor of nima1 a, b, and c). all display a distinctive and dynamic cell cycle-specific distribution. mcnc has weak similarity to saccharomyces cerevisiae def1 within a share ...200818931041
the fungal phytochrome fpha from aspergillus nidulans.the red light-sensing photoreceptor fpha from aspergillus nidulans is involved in the regulation of developmental processes in response to light. here we present extended biochemical and spectroscopic characterization of recombinant fpha using a synthetic gene with host-adapted codon usage. the recombinant photosensory domain fphan753 was shown to display all features of a bona fide phytochrome. it covalently binds biliverdin as chromophore and undergoes red/far-red light-inducible photoconversi ...200818931394
aspergillus nidulans udp-galactopyranose mutase, encoded by ugma plays key roles in colony growth, hyphal morphogenesis, and conidiation.growing resistance to current anti-fungal drugs is spurring investigation of new targets, including those in fungal wall metabolism. galactofuranose (galf) is found in the cell walls of many fungi including aspergillus fumigatus, which is currently the most prevalent opportunistic fungal pathogen in developed countries, and a. nidulans, a closely-related, tractable model system. udp-galactopyranose mutase (ugm) converts udp-galactopyranose into udp-galf prior to incorporation into the fungal wal ...200818935967
depletion of the mobb and cota complex in aspergillus nidulans causes defects in polarity maintenance that can be suppressed by the environment stress.polarized growth is a central feature in eukaryotes. establishment and maintenance of cell polarity are coordinated by signaling pathways. in this study, we have identified mobb is required for the regulation of cell polarity in aspergillus nidulans. depletion of mobb by alca (p) promoter repression or deletion of mobb abolished conidiation completely, and induced severe growth defects. mobb mutants showed abnormal nuclear segregation with increased number of nuclei in spores, but the formation ...200818832040
characterization of bzip-type transcription factor atfa with reference to stress responses of conidia of aspergillus nidulans.microorganisms growing in natural habitats are permanently confronted with a wide variety of external stresses. in fungi, including aspergillus nidulans, one of the general and ultimate strategies to survive in harsh habitats is the development of stress-tolerant conidia. in this study, we found that one of the basic-region leucine zipper transcription factors, named atfa, plays a crucial role in the acquisition of tolerance against oxidative and heat stress on conidia, but not on mycelia, altho ...200818838792
fe(ii)/alpha-ketoglutarate hydroxylases involved in nucleobase, nucleoside, nucleotide, and chromatin metabolism.fe(ii)/alpha-ketoglutarate-dependent hydroxylases uniformly possess a double-stranded beta-helix fold with two conserved histidines and one carboxylate coordinating their mononuclear ferrous ions. oxidative decomposition of the alpha-keto acid is proposed to generate a ferryl-oxo intermediate capable of hydroxylating unactivated carbon atoms in a myriad of substrates. this perspective focuses on a subgroup of these enzymes that are involved in pyrimidine salvage, purine decomposition, nucleoside ...200818813363
in vitro evaluation of penicillium digitatum sacc strains sensitivity to various fungicides from jordan.this investigation is the first report in jordan, aimed for in vitro evaluation of six fungicides and their combinations, to control the post harvest green mold (penicillium digitatum) of citrus fruits. thirty one different concentrations (0.01-3000 microg ml(-1)) of each fungicide, in addition to 6 combined concentrations from each of 7 fungicide mixtures, were tested using agar well diffusion method against four fungal strains. regression analysis, one way anova and post hoc multiple compariso ...200818819638
invasive aspergillus nidulans infection in a patient with chronic granulomatous disease. 200818783555
genomics of industrial aspergilli and comparison with toxigenic relatives.aspergillus oryzae has been used in japanese fermentation industries for more than a thousand years. the species produces large amounts of various hydrolytic enzymes and has been successfully applied to modern biotechnology. the size of the a. oryzae genome (37.5 mb) is very close to that of a. flavus and a. niger, and 20-30% larger than that of either a. nidulans or a. fumigatus. a. oryzae and a. flavus have exactly the same number of aspartic proteinase genes, of which each orthologous pair sh ...200818798040
characterization and heterologous expression of an age-dependent fungal/bacterial type chitinase of aspergillus nidulans.under carbon starvation, aspergillus nidulans produced a fungal/bacterial type chitinase, chib. the chib gene was cloned and subcloned into pjc40 expression vector containing a 10xhis fusion tag, and the chib protein was expressed heterologously in escherichia coli. recombinant and native chib enzymes shared the same optimal ph ranges and showed similar substrate specificities with endo-acting cleavage patterns.200818800599
purification, characterization and crystallization of an extracellular alkaline protease from aspergillus nidulans ha-10.aspergillus nidulans is a highly potent fungus used in the production of alkaline protease. extracellular alkaline protease was purified from a. nidulans in a two-step procedure involving ammonium sulphate precipitation and sephadex g-100 column chromatography. the molecular mass of the enzyme was determined to be 42 kda by sds-page. the enzyme activity was also analyzed by zymogram with gelatin. the enzyme was more stable over a wide range of ph (6-10) and the temperatures up to 50 degrees c. i ...200818702069
ctf1, a transcriptional activator of cutinase and lipase genes in fusarium oxysporum is dispensable for virulence.cutinolytic enzymes are secreted by fungal pathogens attacking the aerial parts of the plant, to facilitate penetration of the outermost cuticular barrier of the host. the role of cutinases in soil-borne root pathogens has not been studied thus far. here we report the characterization of the zinc finger transcription factor ctf1 from the vascular wilt fungus fusarium oxysporum, a functional orthologue of ctf1alpha that controls expression of cutinase genes and virulence in the pea stem pathogen ...200818705871
evolutionary history of the ancient cutinase family in five filamentous ascomycetes reveals differential gene duplications and losses and in magnaporthe grisea shows evidence of sub- and neo-functionalization.* the cuticle is the first barrier for fungi that parasitize plants systematically or opportunistically. here, the evolutionary history is reported of the multimembered cutinase families of the plant pathogenic ascomycetes magnaporthe grisea, fusarium graminearum and botrytis cinerea and the saprotrophic ascomycetes aspergillus nidulans and neurospora crassa. * molecular taxonomy of all fungal cutinases demonstrates a clear division into two ancient subfamilies. no evidence was found for lateral ...200818713314
specific interdomain synergy in the uapa transporter determines its unique specificity for uric acid among nat carriers.uapa, a uric acid-xanthine permease of aspergillus nidulans, has been used as a prototype to study structure-function relationships in the ubiquitous nucleobase-ascorbate transporter (nat) family. using novel genetic screens, rational mutational design, chimeric nat molecules, and extensive transport kinetic analyses, we show that dynamic synergy between three distinct domains, transmembrane segment (tms)1, the tms8-9 loop, and tms12, defines the function and specificity of uapa. the tms8-9 loop ...200818718842
elusive origins of the extra genes in aspergillus oryzae.the genome sequence of aspergillus oryzae revealed unexpectedly that this species has approximately 20% more genes than its congeneric species a. nidulans and a. fumigatus. where did these extra genes come from? here, we evaluate several possible causes of the elevated gene number. many gene families are expanded in a. oryzae relative to a. nidulans and a. fumigatus, but we find no evidence of ancient whole-genome duplication or other segmental duplications, either in a. oryzae or in the common ...200818725939
inducible rna interference of brlabeta in aspergillus nidulans.an inducible rna interference (rnai) construct composed of inverted repeating alca promoters flanking the developmental regulatory gene brlabeta was tested in aspergillus nidulans. on inducing medium, the rnai strains failed to sporulate and lacked brlaalpha and brlabeta expression. rnai was specific for brlabeta, but not brlaalpha, silencing, indicating brlaalpha regulation by brlabeta.200818757565
the asexual pathogen aspergillus fumigatus expresses functional determinants of aspergillus nidulans sexual development.the major fungal pathogen of humans, aspergillus fumigatus, lacks a defined sexual cycle, although the presence of genes encoding putative mating type idiomorphs and regulators of aspergillus sexual development heightens the potential for cryptic sexuality in this deuteromycete. to test the functionality of these genetic determinants, we transferred the alpha box-encoding mat1-1 idiomorph from an a. fumigatus isolate to the homothallic fertile species aspergillus nidulans. abundant formation of ...200818757566
gdp-mannose pyrophosphorylase is essential for cell wall integrity, morphogenesis and viability of aspergillus fumigatus.gdp-mannose pyrophosphorylase (gmpp) catalyses the synthesis of gdp-mannose, which is the precursor for the mannose residues in glycoconjugates, using mannose 1-phosphate and gtp as substrates. repression of gmpp in yeast leads to phenotypes including cell lysis, defective cell wall, and failure of polarized growth and cell separation. although several gmpps have been isolated and characterized in filamentous fungi, the physiological consequences of their actions are not clear. in this study, af ...200818757806
an evolutionary conserved d-galacturonic acid metabolic pathway operates across filamentous fungi capable of pectin degradation.transcriptome analysis of aspergillus niger transfer cultures grown on galacturonic acid media identified a highly correlating cluster of four strongly induced hypothetical genes linked with a subset set of genes encoding pectin degrading enzymes. three of the encoded hypothetical proteins now designated gaaa to gaac are directly involved in further galacturonic acid catabolism. functional and biochemical analysis revealed that gaaa is a novel d-galacturonic acid reductase. two non-allelic asper ...200818768163
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