PMID(sorted descending)
proteomic response of the biological control fungus trichoderma atroviride to growth on the cell walls of rhizoctonia solani.trichoderma atroviride has a natural ability to parasitise phytopathogenic fungi such as rhizoctonia solani and botrytis cinerea, therefore providing an environmentally sound alternative to chemical fungicides in the management of these pathogens. two-dimensional electrophoresis was used to display cellular protein patterns of t. atroviride (t. harzianum p1) grown on media containing either glucose or r. solani cell walls. protein profiles were compared to identify t. atroviride proteins up-regu ...200515856359
visualizing nuclear migration during conidiophore development in aspergillus nidulans and aspergillus oryzae: multinucleation of conidia occurs through direct migration of plural nuclei from phialides and confers greater viability and early germination in aspergillus oryzae.nuclear migration is indispensable for normal growth, differentiation, and development, and has been studied in several fungi including aspergillus nidulans and neurospora crassa. to better characterize nuclear movement and its consequences during conidiophore development, conidiation, and conidial germination, we performed confocal microscopy and time-lapse imaging on a. nidulans and aspergillus oryzae strains expressing the histone h2b-egfp fusion protein. active trafficking of nuclei from a v ...200515849413
discovery of a novel superfamily of type iii polyketide synthases in aspergillus oryzae.identification of genes encoding type iii polyketide synthase (pks) superfamily members in the industrially useful filamentous fungus, aspergillus oryzae, revealed that their distribution is not specific to plants or bacteria. among other aspergilli (aspergillus nidulans and aspergillus fumigatus), a. oryzae was unique in possessing four chalcone synthase (chs)-like genes (csya, csyb, csyc, and csyd). expression of csya, csyb, and csyd genes was confirmed by rt-pcr. comparative genome analyses r ...200515845386
small interfering rnas that trigger posttranscriptional gene silencing are not required for the histone h3 lys9 methylation necessary for transgenic tandem repeat stabilization in neurospora neurospora crassa, the introduction of a transgene can lead to small interfering rna (sirna)-mediated posttranscriptional gene silencing (ptgs) of homologous genes. sirnas can also guide locus-specific methylation of lys9 of histone h3 (lys9h3) in schizosaccharomyces pombe. here we tested the hypothesis that transgenically derived sirnas may contemporaneously both activate the ptgs mechanism and induce chromatin modifications at the transgene and the homologous endogenous gene. we carried out ...200515831483
a catalytic subunit of cyclic amp-dependent protein kinase, pkac-1, regulates asexual differentiation in neurospora crassa.a cyclic amp (camp)-dependent protein kinase pathway has been shown to regulate growth, morphogenesis and virulence in filamentous fungi. however, the precise mechanisms of regulation through the pathway remain poorly understood. in neurospora crassa, the cr-1 adenylate cyclase mutant exhibits colonial growth with short aerial hyphae bearing conidia, and the mcb mutant, a mutant of the regulatory subunit of camp-dependent protein kinase (pka), shows the loss of growth polarity at the restrictive ...200515824453
collateral damage: spread of repeat-induced point mutation from a duplicated dna sequence into an adjoining single-copy gene in neurospora crassa.repeat-induced point mutation (rip) is an unusual genome defense mechanism that was discovered in neurospora crassa. rip occurs during a sexual cross and induces numerous g : c to a : t mutations in duplicated dna sequences and also methylates many of the remaining cytosine residues. we measured the susceptibility of the erg-3 gene, present in single copy, to the spread of rip from duplications of adjoining sequences. genomic segments of defined length (1, 1.5 or 2 kb) and located at defined dis ...200515824437
analysis of circadian output rhythms of gene expression in neurospora and mammalian cells in culture.the true biology of chronobiology lies in the spectrum of processes that are controlled by the circadian clock. although this biology plays out at the level of the whole organism, it derives, finally, from clock-driven changes in physiology, and frequently in gene expression, that occur at the level of individual cells. for this reason, analysis of gene expression rhythms measured in cell culture or in organisms that elaborate only a few cell types provides insights not possible in multicellular ...200515817297
analysis of circadian rhythms in neurospora: overview of assays and genetic and molecular biological manipulation.the eukaryotic filamentous fungus neurospora crassa is a tractable model system that has provided numerous insights into the molecular basis of circadian rhythms. in the core circadian clock feedback loop, wc-1 and wc-2 interact via pas domains to heterodimerize, and this complex acts both as the circadian photoreceptor and, in the dark, as a transcription factor that promotes the expression of the frq gene. in the negative step of the loop, dimers of frq feed back to block the activity of the w ...200515817284
blue light negatively regulates the sexual filamentation via the cwc1 and cwc2 proteins in cryptococcus neoformans.cryptococcus neoformans is a heterothallic basidiomycetous yeast that primarily infects immunocompromised individuals. dikaryotic hyphae resulting from the fusion of the mata and matalpha mating type strains represent the filamentous stage in the sexual life cycle of c. neoformans. in this study we demonstrate that the production of dikaryotic filaments is inhibited by blue light. to study blue light photoresponse in c. neoformans, we have identified and characterized two genes, cwc1 and cwc2, w ...200515813738
a kinase for light and time.the eukaryotic filamentous fungus neurospora crassa has proven to be a dependable model system for the analysis of light-regulated gene expression and circadian rhythmicity. the molecular basis of the core circadian clock is a transcription/translation-based feedback loop in which a heterodimer of the white-collar 1 (wc-1) and white-collar 2 (wc-2) proteins act as a transcription factor to promote expression of the negative elements in the clock, frq mrna and frq protein. additionally, wc-1 is a ...200515813724
cytoplasmic contractions in growing fungal hyphae and their morphogenetic light microscopy of the apical and subapical regions of growing hyphae of several fungal species revealed the existence of momentary synchronized motions of subcellular organelles. first discovered in a temperature-sensitive morphological mutant (ramosa-1) of aspergillus niger, these seemingly spontaneous cytoplasmic contractions were also detected in wild-type hyphae of a. niger, neurospora crassa, and trichoderma atroviride. cytoplasmic contractions in all fungi lasted about 1 s ...200515812630
biochemical characterization of neurospora crassa glycogenin (gnn), the self-glucosylating initiator of glycogen synthesis.glycogenin acts in the initiation step of glycogen biosynthesis by catalyzing a self-glucosylation reaction. in a previous work [de paula et al., arch. biochem. biophys. 435 (2005) 112-124], we described the isolation of the cdna gnn, which encodes the protein glycogenin (gnn) in neurospora crassa. this work presents a set of biochemical and functional studies confirming the gnn role in glycogen biosynthesis. kinetic experiments showed a very low gnn k(m) (4.41 microm) for the substrate udp-gluc ...200515811343
a mitogen-activated protein kinase pathway essential for mating and contributing to vegetative growth in neurospora kinases homologous to saccharomyces cerevisiae fus3p/kss1p have been identified in plant pathogenic fungi and are required for pathogenicity and sexual reproduction. to better understand the role of map kinase signaling in neurospora crassa, and to identify downstream target genes of the pathway, we isolated, cloned, and disrupted the fus3 homolog mak-2. ste12p is a transcription factor target of fus3p that activates genes of the mating pathway in yeast, and we also characterized the n. cras ...200515802524
srs2 and recq homologs cooperate in mei-3-mediated homologous recombination repair of neurospora crassa.homologous recombination and post-replication repair facilitate restart of stalled or collapsed replication forks. the srs2 gene of saccharomyces cerevisiae encodes a 3'-5' dna helicase that functions both in homologous recombination repair and in post-replication repair. this study identifies and characterizes the srs2 homolog in neurospora crassa, which we call mus-50. a knockout mutant of n.crassa, mus-50, is sensitive to several dna-damaging agents and genetic analyses indicate that it is ep ...200515800214
antifungal activity and studies on mode of action of novel xanthoxyline-derived chalcones.chalcones and chalcone-like compounds, most of them new ones, prepared by base-catalyzed condensation of appropriate aldehydes and xanthoxyline, were tested for antifungal properties against a panel of yeasts, hialohyphomycetes as well as dermatophytes with the agar dilution assay. results indicate that neither the sole presence of a "xanthoxyline-like" substitution pattern nor a 2'-oh substituent on ring a are sufficient for these compounds to have antifungal properties. the chalcone 3-(2-chlor ...200515799012
genes of the thymidine salvage pathway: thymine-7-hydroxylase from a rhodotorula glutinis cdna library and iso-orotate decarboxylase from neurospora crassa.genes for two enzymes in the thymidine salvage pathway, thymine-7-hydroxylase (thase; official name thymine dioxygenase) and iso-orotate decarboxylase (idcase) have been isolated from fungal sources. thase was isolated from a rhodotorula glutinis cdna library using a degenerate oligonucleotide based on the published amino acid sequence. the coding sequence was transferred to an escherichia coli expression system, from which recombinant thase activity was measured using 14c-labeled thymine. the t ...200515794921
purification and partial characterization of a paracoccidioides brasiliensis protein with capacity to bind to extracellular matrix proteins.microorganisms adhere to extracellular matrix proteins by means of their own surface molecules. paracoccidioides brasiliensis conidia have been shown to be capable of interacting with extracellular matrix proteins. we aimed at determining the presence of fungal proteins that could interact with extracellular matrix protein and, if found, attempt their purification and characterization. various extracts were prepared from p. brasiliensis mycelial and yeast cultures (total homogenates, beta-mercap ...200515784595
cross-species microarray hybridization to identify developmentally regulated genes in the filamentous fungus sordaria macrospora.the filamentous fungus sordaria macrospora forms complex three-dimensional fruiting bodies that protect the developing ascospores and ensure their proper discharge. several regulatory genes essential for fruiting body development were previously isolated by complementation of the sterile mutants pro1, pro11 and pro22. to establish the genetic relationships between these genes and to identify downstream targets, we have conducted cross-species microarray hybridizations using cdna arrays derived f ...200515778868
novel g-protein-coupled receptor-like proteins in the plant pathogenic fungus magnaporthe grisea.the g-protein-coupled receptors (gpcrs) are one of the largest protein families in human and other animal genomes, but no more than 10 gpcrs have been characterized in fungi. do fungi contain only this handful or are there more receptors to be discovered? we asked this question using the recently sequenced genome of the fungal plant pathogen magnaporthe grisea.200515774025
fluffy, the major regulator of conidiation in neurospora crassa, directly activates a developmentally regulated hydrophobin gene.the fluffy (fl) gene of neurospora crassa is required for asexual sporulation and encodes an 88 kda polypeptide containing a typical fungal zn2cys6 dna-binding motif. identification of genes regulated by fl will provide insight into how fungi regulate growth during morphogenesis. as a step towards identifying the target genes on which fl may act, we sought to define target sequences to which the fl protein binds. the dna binding domain of fl was expressed in escherichia coli as a fusion with glu ...200515773996
the post-transcriptional gene silencing machinery functions independently of dna methylation to repress a line1-like retrotransposon in neurospora gene silencing (ptgs) involving small interfering rna (sirna)-directed degradation of rna transcripts and transcriptional silencing via dna methylation have each been proposed as mechanisms of genome defence against invading nucleic acids, such as transposons and viruses. furthermore, recent data from plants indicates that many transposons are silenced via a combination of the two mechanisms, and sirnas can direct methylation of transposon sequences. we investigated the cont ...200515767281
characterization of mutations in the two-component histidine kinase gene abnik1 from alternaria brassicicola that confer high dicarboximide and phenylpyrrole resistance.highly iprodione- and fludioxonil-resistant field and laboratory isolates of a. brassicicola were found to be either moderately sensitive or tolerant to osmotic stress. abnik1, a two-component histidine kinase gene, was isolated from a fungicide-sensitive strain. the predicted protein possessed the six tandem amino acid repeats at the n-terminal end, which is a landmark of osmosensor histidine kinases from filamentous fungi. a comparison of the nucleic acid sequences of the abnik1 gene from fung ...200515765227
functional and structural analysis of catalase oxidized by singlet oxygen.purified catalase-1 (cat-1) from neurospora crassa asexual spores is oxidized by singlet oxygen giving rise to active enzyme forms with different electrophoretic mobility. these enzyme forms are detected in vivo under stress conditions and during development at the start of the asexual morphogenetic transitions. cat-1 heme b is oxidized to heme d by singlet oxygen. here, we describe functional and structural comparisons of the non-oxidized enzyme with the fully oxidized one. using a broad h(2)o( ...200515760714
light controls growth and development via a conserved pathway in the fungal kingdom.light inhibits mating and haploid fruiting of the human fungal pathogen cryptococcus neoformans, but the mechanisms involved were unknown. two genes controlling light responses were discovered through candidate gene and insertional mutagenesis approaches. deletion of candidate genes encoding a predicted opsin or phytochrome had no effect on mating, while strains mutated in the white collar 1 homolog gene bwc1 mated equally well in the light or the dark. the predicted bwc1 protein shares identity ...200515760278
heterologous expression, purification, and characterization of a highly active xylose reductase from neurospora crassa.a xylose reductase (xr) gene was identified from the neurospora crassa whole-genome sequence, expressed heterologously in escherichia coli, and purified as a his6-tagged fusion in high yield. this enzyme is one of the most active xrs thus far characterized and may be used for the in vitro production of xylitol.200515746370
a two-component histidine kinase of the rice blast fungus is involved in osmotic stress response and fungicide action.we isolated and characterized a histidine kinase gene (hik1) from the rice blast fungus, pyricularia oryzae (magnaporthe grisea). the deduced amino acid sequence of hik1 showed highest similarity (85.7%) to a hybrid-type histidine kinase, os-1/nik-1 of neurospora crassa. disruption of hik1 caused no defect in cell growth on normal media and in pathogenicity to rice plants. the deltahik1 strain acquired resistance to three groups of fungicides (phenylpyrroles, dicarboximides, and aromatic hydroca ...200515707841
possible role of ionic gradients in the apical growth of neurospora crassa.the effects of the ca2+/h+ exchanger a23187 and the k+/h+ exchanger nigericin on the growth of neurospora crassa were analyzed. both ionophores had the same effects on the fungus. they both inhibited growth in liquid media, apical extension being more affected than protein synthesis. a sudden challenge to either ionophore on solid media rapidly stopped hyphal extension. additionally, both ionophores induced profuse mycelium branching and upward hyphal growth. hyphae growing on nigericin-containi ...200415702382
the heterotrimeric g-protein subunits gng-1 and gnb-1 form a gbetagamma dimer required for normal female fertility, asexual development, and galpha protein levels in neurospora crassa.we have identified a gene encoding a heterotrimeric g protein gamma subunit, gng-1, from the filamentous fungus neurospora crassa. gng-1 possesses a gene structure similar to that of mammalian ggamma genes, consisting of three exons and two introns, with introns present in both the open reading frame and 5'-untranslated region. the gng-1 amino acid sequence displays high identity to predicted ggamma subunits from other filamentous fungi, including giberella zeae, cryphonectria parasitica, tricho ...200515701799
a tyrosyl-trna synthetase adapted to function in group i intron splicing by acquiring a new rna binding surface.we determined a 1.95 a x-ray crystal structure of a c-terminally truncated neurospora crassa mitochondrial tyrosyl-trna synthetase (cyt-18 protein) that functions in splicing group i introns. cyt-18's nucleotide binding fold and intermediate alpha-helical domains superimpose on those of bacterial tyrrss, except for an n-terminal extension and two small insertions not found in nonsplicing bacterial enzymes. these additions surround the cyt-18-1 mutation site and are sites of suppressor mutations ...200515694342
gnn is a self-glucosylating protein involved in the initiation step of glycogen biosynthesis in neurospora crassa.the initiation of glycogen synthesis requires the protein glycogenin, which incorporates glucose residues through a self-glucosylation reaction, and then acts as substrate for chain elongation by glycogen synthase and branching enzyme. numerous sequences of glycogenin-like proteins are available in the databases but the enzymes from mammalian skeletal muscle and from saccharomyces cerevisiae are the best characterized. we report the isolation of a cdna from the fungus neurospora crassa, which en ...200515680913
intramolecular recombination and deletions in mitochondrial dna of senescent, a nuclear-gene mutant of neurospora crassa exhibiting "death" neurospora crassa, a nuclear-gene mutant, senescent, derived from a phenotypically normal wild isolate of neurospora intermedia exhibits a 'death' phenotype. regardless of the composition of the culture medium, the mycelium ceases to grow in 2-6 subcultures at 26 degrees c and 1 or 2 subcultures at 34 degrees c. senescence of vegetative mycelium is associated with deficiencies in cytochromes aa3 and b and reduced oxygen uptake. the restriction fragment analysis of mitochondrial dna from senes ...200515670715
the cot1 homologue cpcot1 regulates polar growth and branching and is essential for pathogenicity in claviceps purpurea.claviceps purpurea, the ergot fungus, is a common grass pathogen attacking exclusively young ovaries. its pathogenic development involves an early phase of directed growth (with strictly suppressed branching) towards the floral vascular tissue. since ser/thr protein kinases of the ndr family have been shown to be involved in polar growth and branching in fungi, we have analyzed a c. purpurea homologue of the neurospora crassa cot-1 gene, cpcot1. it encodes a functional homologue of cot1 since it ...200415670709
the neurospora crassa gene responsible for the cut and ovc phenotypes encodes a protein of the haloacid dehalogenase family.light stimulation of carotenogenesis in neurospora crassa, mediated by the white collar proteins, is enhanced in some regulatory mutants, such as vivid and ovc. the gene responsible for the vivid mutation has been identified, but not the one responsible for the ovc phenotype. the ovc mutant is sensitive to high osmotic conditions and allelic with another mutant, cut, also osmosensitive but not affected in carotenogenesis. a phenotypic characterization of both strains is presented. light inductio ...200515661007
silencing of unpaired chromatin and histone h2a ubiquitination in mammalian meiosis.during meiotic prophase in male mammals, the x and y chromosomes are incorporated in the xy body. this heterochromatic body is transcriptionally silenced and marked by increased ubiquitination of histone h2a. this led us to investigate the relationship between histone h2a ubiquitination and chromatin silencing in more detail. first, we found that ubiquitinated h2a also marks the silenced x chromosome of the barr body in female somatic cells. next, we studied a possible relationship between h2a u ...200515657431
neutral glycolipids of the filamentous fungus neurospora crassa: altered expression in plant defensin-resistant defend themselves against fungal pathogens, plants produce numerous antifungal proteins and peptides, including defensins, some of which have been proposed to interact with fungal cell surface glycosphingolipid components. although not known as a phytopathogen, the filamentous fungus neurospora crassa possesses numerous genes similar to those required for plant pathogenesis identified in fungal pathogens (galagan, j. e., et al. 2003. nature 422: 859-868), and it has been used as a model for s ...200515654124
a model for the neurospora circadian clock.circadian clocks are important biological oscillators that generally involve two feedback loops. here, we propose a new model for the neurospora crassa circadian clock. first, we model its main negative feedback loop, including only experimentally well-documented reactions, the transcriptional activation of frequency (frq) by the white-collar complex (wcc), and the post-transcriptional dimerization of frq with wcc. this main loop is sufficient for oscillations and a similar one lies at the core ...200515653726
[a simple method to correct genetic distance between linked genes and a correction of calculating data in tetrad analysis in neurospora crassa].the present paper is dealing with a simple method to correct the distance of linked genes in tetrad analysis in neurospora crassa. it is suggested that the data of 4-thread double crossing over should be added in two single crossing over respectively in centromere maping when calculating crossover value of the two genes locating across the centromere.200315639882
gene silencing pathway rna-dependent rna polymerase of neurospora crassa: yeast expression and crystallization of selenomethionated qde-1 protein.the rna-dependent rna polymerase, qde-1, is a component of the rna silencing pathway in neurospora crassa. the enzymatically active carboxy-terminal fragment qde-1 deltan has been expressed in saccharomyces cerevisiae in the presence and absence of selenomethionine (semet). the level of semet incorporation was estimated by mass spectrometry to be approximately 98%. both native and semet proteins were crystallized in space group p2(1) with unit cell parameters a=101.2, b=122.5, c=114.4a, beta=108 ...200515629662
[new approach in the explaining of the morgan law in genetics teaching].using the model of broad and narrow way, the paper introduces a new approach in the explaining of a few basic concepts in the morgan law. the paper introduces a thorough inquiry into the applying condition of the three-factor crosses, and finds the source of the difference between the crossover frequency (f(c)) and recombination frequency (f(r)) of the non-adjacent factors in the three-factor crosses in neurospora crassa.200415626673
copper alone, but not oxidative stress, induces copper-metallothionein gene in neurospora crassa.two metal response elements, flanking an antioxidant response element, were identified in regions upstream (-3730 bp) to copper metallothionein (cumt) gene of neurospora crassa. presence of copper in culture media, but not of pro-oxidants like h2o2 or menadione, induced cumt gene expression that could not be completely abolished by antioxidants such as n-acetyl cysteine and ascorbic acid. gel shift assays revealed the ability of nuclear extracts from copper induced cultures to bind pcr-amplified ...200515621418
a recq gene homolog from the basidiomycetous mushroom lentinula edodes: sequence analysis and expression.we cloned and sequenced a recq gene homolog from the basidiomycetous mushroom lentinula edodes (le.). this gene, named le.recq, was found to have a coding capacity of 945 amino acids (aa) and be interrupted by 11 small introns. the deduced le.recq protein was clearly smaller than other fungal recq proteins such as neurospora crassa qde3 (1955 aa), schizosaccharomyces pombe rqh1 (1328 aa), and saccharomyces cerevisiae sgs1 (1447 aa). it exhibited the highest homology to the arabidopsis thaliana r ...200415618631
the splicing of yeast mitochondrial group i and group ii introns requires a dead-box protein with rna chaperone i and ii introns self-splice in vitro, but require proteins for efficient splicing in vivo, to stabilize the catalytically active rna structure. recent studies showed that the splicing of some neurospora crassa mitochondrial group i introns additionally requires a dead-box protein, cyt-19, which acts as an rna chaperone to resolve nonnative structures formed during rna folding. here we show that, in saccharomyces cerevisiae mitochondria, a related dead-box protein, mss116p, is required for ...200415618406
gene discovery and gene expression in the rice blast fungus, magnaporthe grisea: analysis of expressed sequence tags.over 28,000 expressed sequence tags (ests) were produced from cdna libraries representing a variety of growth conditions and cell types. several magnaporthe grisea strains were used to produce the libraries, including a nonpathogenic strain bearing a mutation in the pmk1 mitogen-activated protein kinase. approximately 23,000 of the ests could be clustered into 3,050 contigs, leaving 5,127 singleton sequences. the estimate of 8,177 unique sequences indicates that over half of the genes of the fun ...200415597739
in vitro and in vivo analyses of a phe/tyr switch controlling product specificity of histone lysine methyltransferases.the functional significance of mono-, di-, and tri-methylation of lysine residues within histone proteins is under investigation. evidence from several model organisms suggests that different methylated states of h3 lys(9) (h3k9) are generated by specific histone methyltransferases (mtases) to mark distinct types of silent chromatin. sequence alignment of all histone lysine mtases with known product specificity suggested that a key residue in the active site determines how many methyl groups the ...200415590646
mechanism of nickel resistance in a cobalt-resistant wall-less mutant of neurospora crassa (fz; sg; os-1).a cobalt-resistant wall-less mutant of n. crassa (cor-sl) characterized previously was also found to be 3-fold more resistant to nickel when compared to the parent wall-less mutant (w-sl). the cor-sl strain accumulates relatively lower amounts of nickel when compared to w-sl. sub-cellular fractionation showed significant quantities of nickel to be associated with nuclear and mitochondrial fractions in both the wall-less mutants. however significant differences were observed in vacuolar fractions ...200415587120
involvement of a flavosemiquinone in the enzymatic oxidation of nitroalkanes catalyzed by 2-nitropropane dioxygenase.2-nitropropane dioxygenase (ec catalyzes the oxidation of nitroalkanes into their corresponding carbonyl compounds and nitrite. in this study, the ncd-2 gene encoding for the enzyme in neurospora crassa was cloned, expressed in escherichia coli, and the resulting enzyme was purified. size exclusion chromatography, heat denaturation, and mass spectroscopic analyses showed that 2-nitropropane dioxygenase is a homodimer of 80 kda, containing a mole of non-covalently bound fmn per mole o ...200415582992
pcmtr, an aromatic and neutral aliphatic amino acid permease of penicillium chrysogenum.the gene encoding an aromatic and neutral aliphatic amino acid permease of penicillium chrysogenum was cloned, functionally expressed and characterized in saccharomyces cerevisiae m4276. the permease, designated pcmtr, is structurally and functionally homologous to mtr of neurospora crassa, and unrelated to the amino acid permease (aap) family which includes most amino acid permeases in fungi. database searches of completed fungal genome sequences reveal that mtr type permeases are not widely di ...200415581852
survey of simple sequence repeats in completed fungal genomes.the use of simple sequence repeats or microsatellites as genetic markers has become very popular because of their abundance and length variation between different individuals. ssrs are tandem repeat units of 1 to 6 base pairs that are found abundantly in many prokaryotic and eukaryotic genomes. this is the first study examining and comparing ssrs in completely sequenced fungal genomes. we analyzed and compared the occurrences, relative abundance, relative density, most common, and longest ssrs i ...200515563717
genomic organization of the neurospora crassa gsn gene: possible involvement of the stre and hse elements in the modulation of transcription during heat shock.glycogen synthase, an enzyme involved in glycogen biosynthesis, is regulated by phosphorylation and by the allosteric ligand glucose-6-phosphate (g6p). in addition, enzyme levels can be regulated by changes in gene expression. we recently cloned a cdna for glycogen synthase ( gsn) from neurospora crassa, and showed that gsn transcription decreased when cells were exposed to heat shock (shifted from 30 degrees c to 45 degrees c). in order to understand the mechanisms that control gsn expression, ...200415558319
rna silencing in aspergillus nidulans is independent of rna-dependent rna polymerases.the versatility of rna-dependent rna polymerases (rdrps) in eukaryotic gene silencing is perhaps best illustrated in the kingdom fungi. biochemical and genetic studies of schizosaccharomyces pombe and neurospora crassa show that these types of enzymes are involved in a number of fundamental gene-silencing processes, including heterochromatin regulation and rna silencing in s. pombe and meiotic silencing and rna silencing in n. crassa. here we show that aspergillus nidulans, another model fungus, ...200515545645
neurospora crassa cypbp37: a cytosolic stress protein that is able to replace yeast thi4p function in the synthesis of vitamin b1.recently, we identified cypbp37 of neurospora crassa as a binding partner of cyclophilin41. cypbp37 function had not yet been described, although orthologs in other organisms have been implicated in the biosynthesis of the thiazole moiety of thiamine (vitamin b1) and/or stress-related pathways. here, cypbp37 is characterized as an abundant cytosolic protein with a functional nad-binding site. saccharomyces cerevisiae mutants lacking thi4p (the cypbp37 ortholog) are auxotrophic for vitamin b1 (th ...200415544818
conservation and evolution of cis-regulatory systems in ascomycete fungi.relatively little is known about the mechanisms through which gene expression regulation evolves. to investigate this, we systematically explored the conservation of regulatory networks in fungi by examining the cis-regulatory elements that govern the expression of coregulated genes. we first identified groups of coregulated saccharomyces cerevisiae genes enriched for genes with known upstream or downstream cis-regulatory sequences. reasoning that many of these gene groups are coregulated in rel ...200415534694
the neurospora circadian system.the eukaryotic filamentous fungus neurospora crassa has proven to be a durable and dependable model system for the analysis of the cellular and molecular bases of circadian rhythms. pioneering genetic analyses identified clock genes, and beginning with the cloning of frequency (frq), work over the past 2 decades has revealed the molecular basis of a core circadian clock feedback loop that has illuminated our understanding of circadian oscillators in microbes, plants, and animals. in this transcr ...200415534321
transcriptional response to glucose starvation and functional analysis of a glucose transporter of neurospora crassa.the response to glucose availability in neurospora crassa was characterized by measuring transcript levels of 1335 genes represented on a cdna microarray. we found that 19% of the 1335 genes were regulated at least twofold in response to glucose deprivation. several sugar transporter homologs were found to be regulated by glucose. functional analysis of one of these, hgt-1, indicates that it encodes a high-affinity glucose transporter. comparing n. crassa profiling data with the published diauxi ...200415531214
the control of mating type heterokaryon incompatibility by vib-1, a locus involved in het-c heterokaryon incompatibility in neurospora crassa.the mating-type (mat) locus of neurospora crassa has a dual function. it is required for mating during sexual development, but it also mediates heterokaryon incompatibility following hyphal fusion during vegetative growth. previously, it was determined that mutations in vib-1, which encodes a putative transcriptional regulator, suppress het-c heterokaryon incompatibility. this study showed that mutations in vib-1 suppress mat heterokaryon incompatibility in a/a partial diploids; suppression in ( ...200415531211
blr-1 and blr-2, key regulatory elements of photoconidiation and mycelial growth in trichoderma fungi, phototropism, the induction of carotenogenesis and reproductive structures, and resetting of the circadian rhythm are controlled by blue light. trichoderma atroviride, a fungus used in biological control, sporulates in a synchronized manner following a brief pulse of blue light. due to its apparent simplicity, this response was chosen for pursuing photoreceptor isolation. two genes were cloned, blue-light regulators 1 and 2 (blr-1 and blr-2), similar to the neurospora crassa white-coll ...200415528646
acfkh1, a novel member of the forkhead family, associates with the rfx transcription factor cpcr1 in the cephalosporin c-producing fungus acremonium the filamentous fungus acremonium chrysogenum, a complex regulatory network of transcription factors controls the expression of at least seven cephalosporin c biosynthesis genes. the rfx transcription factor cpcr1 binds to regulatory sequences in the promoter region of cephalosporin c biosynthesis genes, and is involved in the transcriptional regulation of the pcbc gene which encodes isopenicillin n synthase. in this study, we used cpcr1 in a yeast two-hybrid screen to identify potential prot ...200415527986
chitosan as a macroaffinity ligand purification of chitinases by affinity precipitation and aqueous two-phase extractions.(1) chitosan was found to be a suitable macroaffinity ligand for affinity precipitation of chitinase from neurospora crassa, cabbage and puffballs. (2) the activity recoveries of 85, 82 and 90% with concomitant fold purifications in terms of specific activities were 27, 15 and 30 with n. crassa, cabbage and puffballs and were obtained with affinity precipitation. these results were obtained with clarified extracts/homogenates as the starting materials. (3) the incorporation of chitosan in poly(e ...200415527124
a phylogenomic approach to reconstructing the diversification of serine proteases in fungi.using a phylogenomic approach with 10 fungi of very different virulence and habitat, we determined that there was substantial diversification of subtilase-type proteases early in ascomycete history (with subsequent loss in many lineages) but with no comparable diversification of trypsins. patterns of intron loss and the degree of divergence between paralogues demonstrated that the proliferation of proteinase k subtilases and subtilisin type subtilases seen in pathogenic ascomycetes (metarhizium ...200415525405
time-lapse analysis of the circadian rhythms of conidiation and growth rate in neurospora.the filamentous fungus neurospora crassa has frequently served as a model organism for the study of circadian rhythms through its ability to form conidial spores on a daily basis. this phenomenon leaves a spatial pattern of conidiation bands along a solid surface of agar after several days of growth. using time-lapse video, the authors have quantified the rate of conidiation. they have found that conidia do not form at a specified lag time after the growth front is laid down, but rather the band ...200415523111
metabolic highways of neurospora crassa revisited.this chapter describes the metabolic pathways for neurospora crassa in the biosynthesis of amino acids, purines, pyrimidines, vitamins, and cofactors, and for glycolysis, the tca and glyoxylate cycles and the initial stages of the pentose phosphate pathway. for each step in metabolism, the gene or genes within the genome sequence of the species is identified, correlations are made with previously identified genes, and new gene designations are assigned to others. for each gene, details given are ...200415522735
solution structure of cu6 metallothionein from the fungus neurospora crassa.the 3d-solution structure of neurospora crassa cu(6)-metallothionein (ncmt) polypeptide backbone was determined using homonuclear, multidimensional (1)h-nmr spectroscopy. it represents a new metallothionein (mt) fold with a protein chain where the n-terminal half is left-handed and the c-terminal half right-handedly folded around a copper(i)-sulfur cluster. as seen with other mts, the protein lacks definable secondary structural elements; however, the polypeptide fold is unique. the metal coordi ...200415511227
role of unc104/kif1-related motor proteins in mitochondrial transport in neurospora crassa.eukaryotic cells use diverse cytoskeleton-dependent machineries to control inheritance and intracellular positioning of mitochondria. in particular, microtubules play a major role in mitochondrial motility in the filamentous fungus neurospora crassa and in mammalian cells. we examined the role of two novel unc104/kif1-related members of the kinesin family, nkin2 and nkin3, in mitochondrial motility in neurospora. the nkin2 protein is required for mitochondrial interactions with microtubules in v ...200515483054
identification of the protein binding region of s-trityl-l-cysteine, a new potent inhibitor of the mitotic kinesin eg5.human eg5, a mitotic motor of the kinesin superfamily, is involved in the formation and maintenance of the mitotic spindle. the recent discovery of small molecules that inhibit hseg5 by binding to its catalytic motor domain leading to mitotic arrest has attracted more interest in eg5 as a potential anticancer drug target. we have used hydrogen-deuterium exchange mass spectrometry and directed mutagenesis to identify the secondary structure elements that form the binding sites of new eg5 inhibito ...200415476401
introns and splicing elements of five diverse fungi.genomic sequences and expressed sequence tag data for a diverse group of fungi (saccharomyces cerevisiae, schizosaccharomyces pombe, aspergillus nidulans, neurospora crassa, and cryptococcus neoformans) provided the opportunity to accurately characterize conserved intronic elements. an examination of large intron data sets revealed that fungal introns in general are short, that 98% or more of them belong to the canonical splice site (ss) class (5'gu...ag3'), and that they have polypyrimidine tra ...200415470237
genetic evidence for a regulatory pathway controlling alternative oxidase production in neurospora crassa.when the cytochrome-mediated mitochondrial electron transport chain of neurospora crassa is disrupted, an alternative oxidase encoded by the nuclear aod-1 gene is induced. the alternative oxidase donates electrons directly to oxygen from the ubiquininol pool and is insensitive to chemicals such as antimycin a and kcn that affect the standard electron transport chain. to facilitate isolation of mutants affecting regulation of aod-1, a reporter system containing the region upstream of the aod-1 co ...200515466423
efficient gene silencing by expression of double stranded rna in neurospora neurospora crassa, sequence-specific inhibition of endogenous genes can be induced by the introduction of transgenic dna homologous to the target gene, through the mechanism of post-transcriptional gene silencing (ptgs) known as quelling. the application of this strategy to inactivate genes in n. crassa has, to date, been restricted by a limited silencing efficiency and instability of the silenced phenotype. in this study we show that the use of constructs that express hairpin double stranded ...200415465390
turgor regulation in hyphal organisms.turgor regulation in two saprophytic hyphal organisms was examined directly with the pressure probe technique. the ascomycete neurospora crassa, a terrestrial fungi, regulates turgor after hyperosmotic treatments when growing in a minimal medium containing k(+), mg(2+), ca(2+), cl(-), and sucrose. turgor recovery by n. crassa after hyperosmotic treatment is concurrent with changes in ion transport: hyperpolarization of the plasma membrane potential and a decline in transmembrane ion conductance. ...200415465389
[effect of 5-azacytidine on the light-sensitive formation of sexual and asexual reproductive structures in wc-1 and wc-2 mutants of neurospora crassa].under the conditions of nitrogen starvation, illumination by blue light of wc-1 and wc-2 mutants of the ascomycete neurospora crassa failed to stimulate the formation of protoperithecia and inhibit conidiation (contrary to what was observed in the mycelium of the wild-type fungus). the data obtained indicate that wc-1 and wc-2 genes of n. crassa are involved in light-dependent formation of protoperithecia and conidia. the effects of 5-azacytidine (an inhibitor of dna methylation) under the same ...201315455721
studies on the formation of invertase by neurospora crassa. 195015419292
amino acid oxidase of neurospora crassa. 194915407249
nanocapsules: coating for living of the most promising tools for future applications in science and medicine is the use of nanotechnologies. especially self-assembly systems, e.g., polyelectrolyte (pe) capsules prepared by means of the layer-by-layer technique with tailored properties, fulfill the requirements for nano-organized systems in a satisfactory manner. the nano-organized shells are suitable as coating for living cells or artificial tissue to prevent immune response. with these shells, material can be delivered to ...200415382641
unique biosynthesis of dehydroquinic acid?a search of the genomic sequences of the thermophilic microorganisms aquifex aeolicus, archaeoglobus fulgidus, methanobacterium thermoautotrophicum, and methanococcus jannaschii for the first seven enzymes (arog, b, d, e, k, a, and c ) involved in the shikimic acid biosynthetic pathway reveal two key enzymes are missing. the first enzyme in the pathway, 3-deoxy-d-arabino-heptulosonic acid 7-phosphate synthase (arog) and the second enzyme in the pathway, 5-dehydroquinic acid synthase (arob) are " ...200415381397
characterization of pco-1, a newly identified gene which regulates purine catabolism in neurospora.a new gene of neurospora crassa, designated pco-1, was characterized and shown to regulate the expression of several genes which encode enzymes required for the catabolism of purines. unlike the wild type, a pco-1 mutant created by repeat-induced point mutation cannot utilize purines as a nitrogen source. the pco1 protein contains a zn(ii)2cys6 binuclear cluster motif near its n-terminus, followed by a putative coiled-coil motif. a chemical crosslinking experiment demonstrated that pco1 forms ho ...200415378267
a two variable delay model for the circadian rhythm of neurospora crassa.a two variable model with delay in both the variables, is proposed for the circadian oscillations of protein concentrations in the fungal species neurospora crassa. the dynamical variables chosen are the concentrations of frq and wc-1 proteins. our model is a two variable simplification of the detailed model of smolen et al. (j. neurosci. 21 (2001) 6644) modeling circadian oscillations with interlocking positive and negative feedback loops, containing 23 variables. in our model, as in the case o ...200415363927
unusual cys-tyr covalent bond in a large catalase.catalase-1, one of four catalase activities of neurospora crassa, is associated with non-growing cells and accumulates in asexual spores. it is a large, tetrameric, highly efficient, and durable enzyme that is active even at molar concentrations of hydrogen peroxide. catalase-1 is oxidized at the heme by singlet oxygen without significant effects on enzyme activity. here we present the crystal structure of catalase-1 at 1.75a resolution. compared to structures of other catalases of the large cla ...200415342250
gfp as a tool to analyze the organization, dynamics and function of nuclei and microtubules in neurospora crassa.we report the construction of a versatile gfp expression plasmid and demonstrate its utility in neurospora crassa. to visualize nuclei and microtubules, we generated carboxy-terminal fusions of sgfp to neurospora histone h1 (hh1) and beta-tubulin (bml). strong expression of gfp fusion proteins was achieved with the inducible neurospora ccg-1 promoter. nuclear and microtubule organization and dynamics were observed in live vegetative hyphae, developing asci, and ascospores by conventional and con ...200415341912
human mitochondrial complex i assembles through the combination of evolutionary conserved modules: a framework to interpret complex i deficiencies.with 46 subunits, human mitochondrial complex i is the largest enzyme of the oxidative phosphorylation system. we have studied the assembly of complex i in cultured human cells. this will provide essential information about the nature of complex i deficiencies and will enhance our understanding of mitochondrial disease mechanisms. we have found that 143b206 rho zero cells, not containing mitochondrial dna, are still able to form complex i subcomplexes. to further address the nature of these subc ...200415317750
rip: the evolutionary cost of genome defense.repeat-induced point mutation (rip) is a homology-based process that mutates repetitive dna and frequently leads to epigenetic silencing of the mutated sequences through dna methylation. consistent with the hypothesis that rip serves to control selfish dna, an analysis of the neurospora crassa genome sequence reveals a complete absence of intact mobile elements. as in most eukaryotes, the centromeric regions of n. crassa are rich in sequences that are related to transposable elements; however, i ...200415313550
one of the two dicer-like proteins in the filamentous fungi magnaporthe oryzae genome is responsible for hairpin rna-triggered rna silencing and related small interfering rna accumulation.dicer is a ribonuclease iii-like enzyme playing a key role in the rna silencing pathway. genome sequencing projects have demonstrated that eukaryotic genomes vary in the numbers of dicer-like (dcl) proteins from one (human) to four (arabidopsis). two dcl genes, mdl-1 and -2 (magnaporthe dicer-like-1 and -2) have been identified in the genome of the filamentous fungus magnaporthe oryzae. here we show that the knockout of mdl-2 drastically impaired gene silencing of enhanced green fluorescence pro ...200415304480
rnai-dependent and rnai-independent mechanisms contribute to the silencing of riped sequences in neurospora crassa.rna interference (rnai) can silence genes at the transcriptional level by targeting locus-specific lys9h3 methylation or at the post-transcriptional level by targeting mrna degradation. here we have cloned and sequenced genomic regions methylated in lys9h3 in neurospora crassa to test the requirements for components of the rnai pathway in this modification. we find that 90% of clones map to repeated sequences and relics of transposons that have undergone repeat-induced point mutations (rip). we ...200415302921
crystal structure of 3-carboxy-cis,cis-muconate lactonizing enzyme from pseudomonas putida, a fumarase class ii type cycloisomerase: enzyme evolution in parallel pathways.3-carboxy-cis,cis-muconate lactonizing enzymes (cmles), the key enzymes in the protocatechuate branch of the beta-ketoadipate pathway in microorganisms, catalyze the conversion of 3-carboxy-cis,cis-muconate to muconolactones. we have determined the crystal structure of the prokaryotic pseudomonas putida cmle (ppcmle) at 2.6 a resolution. ppcmle is a homotetramer and belongs to the fumarase class ii superfamily. the active site of ppcmle is formed largely by three regions, which are moderately co ...200415301541
crystallization and preliminary x-ray analysis of the nadp-specific glutamate dehydrogenase from neurospora crassa.the nadp-linked glutamate dehydrogenase from neurospora crassa has been crystallized by the hanging-drop method of vapour diffusion in the presence of 0.1 m glutamate. the crystals are trigonal and are in space group p3(1)21 with unit-cell dimensions of a = b = 196.6, c = 102.0 a and with a trimer in the asymmetric unit. a full structure determination of this enzyme will lead to an understanding of the molecular basis of inter-allelic complementation observed with hybrid hexamers of naturally oc ...199515299820
crystallization and preliminary crystallographic analysis of 3-carboxy-cis,cis-muconate lactonizing enzyme from neurospora crassa.crystals of 3-carboxy-cis,cis-muconate lactonizing enzyme (cmle; e.c. from neurospora crassa that diffract to high resolution have been obtained. the crystals belong to the orthorhombic space group p2(1)2(1)2(1) with unit-cell dimensions a = 92.1, b = 159.7, c = 236.6 a (at 103 k) and diffract at most to 2 a resolution. the asymmetric unit of the crystals appears to contain two tetrameric cmle molecules making up a total of 328 kda per asymmetric unit. both cross-linking with glutaralde ...199615299752
large single crystals of the neurospora crassa plasma membrane h+-atpase: an approach to the crystallization of integral membrane proteins.large single crystals of the dodecylmaltoside (ddm) complex of a polytopic integral membrane transport protein, the neurospora plasma membrane h(+)-atpase, have been obtained using an approach that attempts to take into account the possibly radically different physicochemical properties of the protein surfaces and the detergent micellar collar. the overall goal of the crystallization strategy employed was to identify conditions in which the protein surfaces of the ddm-atpase complex are moderate ...199415299430
highly efficient gene replacements in neurospora strains deficient for nonhomologous end-joining.gene disruption and overexpression play central roles in the analysis of gene function. homologous recombination is, in principle, the most efficient method of disrupting, modifying, or replacing a target gene. although homologous integration of exogenous dna into the genome occurs readily in saccharomyces cerevisiae, it is rare in many other organisms. we identified and disrupted neurospora crassa genes homologous to human ku70 and ku80, which encode proteins that function in nonhomologous end- ...200415299145
key differences between lateral and apical branching in hyphae of neurospora crassa.we examined in fine detail growth kinetics and intracellular events during lateral and apical branching in hyphae of neurospora crassa. by high-resolution video-enhanced light microscopy, we found remarkable differences in the events preceding lateral vs apical branching. while apical branching involved a significant disturbance in the apical growth of the parental hypha, lateral branching occurred without any detectable alterations in the growth of the parental hypha. prior to the emergence of ...200415288020
a comparative genomic analysis of the calcium signaling machinery in neurospora crassa, magnaporthe grisea, and saccharomyces cerevisiae.a large number of ca2+ -signaling proteins have been previously identified and characterized in saccharomyces cerevisiae but relatively few have been discovered in filamentous fungi. in this study, a detailed, comparative genomic analysis of ca2+ -signaling proteins in neurospora crassa, magnaporthe grisea, and s. cerevisiae has been made. our blast analysis identified 48, 42, and 40 ca2+ -signaling proteins in n. crassa, m. grisea, and s. cerevisiae, respectively. in n. crassa, m. grisea, and s ...200415288019
alleles of the hotspot cog are codominant in effect on recombination in the his-3 region of neurospora.there are two naturally occurring functional alleles of the recombination hotspot cog, which is located 3.5 kb from the his-3 locus of neurospora crassa. the presence of the cog+ allele in a cross significantly increases recombination in the his-3 region compared to a cross homozygous for the cog allele. data obtained shortly after discovery of cog+ suggested that it was fully dominant to cog. however, a dominant cog+ conflicts with observations of hotspots in saccharomyces cerevisiae and schizo ...200415280230
interaction of mushroom tyrosinase with aromatic amines, o-diamines and o-aminophenols.3-amino-l-tyrosine was found to be a substrate of mushroom tyrosinase, contrary to what had previously been reported in the literature. a series of amino derivatives of benzoic acid were tested as substrates and inhibitors of the enzyme. 3-amino-4-hydroxybenzoic acid, 4-amino-3-hydroxybenzoic acid and 3,4-diaminobenzoic acid were oxidized by this enzyme, as previously reported for neurospora crassa tyrosinase, but 4-aminobenzoic acid and 3-aminobenzoic acid were not. interestingly, 3-amino-4-hyd ...200415279888
photomorphogenesis in the hypogeous fungus tuber borchii: isolation and characterization of tbwc-1, the homologue of the blue-light photoreceptor of neurospora crassa.truffles form a group of plant-symbiotic ascomycetes whose hypogeous life cycle is poorly understood. here we present initial evidence for the influence of light on tuber borchii mycelial growth and the identification and cloning of a gene, tbwc-1, homologous to a blue-light photoreceptor of neurospora crassa. blue-light irradiation of t. borchii colonies inhibits their apical growth. it also alters apical growth in n. crassa. in neurospora, the response is controlled by a nuclear photoreceptor, ...200415275664
functional characterization of the conserved "glk" motif in mitochondrial porin from neurospora crassa.mitochondrial porin facilitates the diffusion of small hydrophilic molecules across the mitochondrial outer membrane. despite low sequence similarity among porins from different species, a "glycine-leucine-lysine" (glk) motif is conserved in mitochondrial and neisseria porins. to investigate the possible roles of these conserved residues, including their hypothesized participation in atp binding by the protein, we replaced the lysine residue of the glk motif of neurospora crassa porin with gluta ...200015254370
the pho80-like cyclin of aspergillus nidulans regulates development independently of its role in phosphate saccharomyces cerevisiae, phosphate acquisition enzymes are regulated by a cyclin-dependent kinase (pho85), a cyclin (pho80), the cyclin-dependent kinase inhibitor pho81, and the helix-loop-helix transcription factor pho4 (the pho system). previous studies in aspergillus nidulans indicate that a pho85-like kinase, phoa, does not regulate the classic pho system but regulates development in a phosphate-dependent manner. a pho80-like cyclin has now been isolated through its interaction with phoa ...200415247298
a nitrate-induced frq-less oscillator in neurospora crassa.when nitrate is the only nitrogen source, neurospora crassa's nitrate reductase (nr) shows endogenous oscillations in its nitrate reductase activity (nra) on a circadian time scale. these nra oscillations can be observed in darkness or continuous light conditions and also in a frq(9) mutant in which no functional frq protein is formed. even in a white-collar-1 knockout mutant, nra oscillations have been observed, although with a highly reduced amplitude. this indicates that the nra oscillations ...200415245647
the wild-type circadian period of neurospora is encoded in the residual network of the null frq mutants.we model theoretically the response of the widely studied circadian oscillator of neurospora crassa to inactivation of the frq gene. the resulting organism has been termed "arrhythmic" under constant conditions. under entrainment to periodic temperature cycles roenneberg, merrow and coworkers have shown that the phase angle at which spore formation occurs depends on the entrainment period, curiously even in the null frq mutants (frq9 and frq10). we show that such a response does not imply the pr ...200415234207
bioremediation of 60co from simulated spent decontamination solutions.bioremediation of 60co from simulated spent decontamination solutions by utilizing different biomass of (neurospora crassa, trichoderma viridae, mucor recemosus, rhizopus chinensis, penicillium citrinum, aspergillus niger and, aspergillus flavus) fungi is reported. various fungal species were screened to evaluate their potential for removing cobalt from very low concentrations (0.03-0.16 microm) in presence of a high background of iron (9.33 mm) and nickel (0.93 mm) complexed with edta (10.3 mm) ...200415207568
a pheromone receptor gene, pre-1, is essential for mating type-specific directional growth and fusion of trichogynes and female fertility in neurospora crassa.neurospora crassa is a heterothallic filamentous fungus with two mating types, mat a and mat a. its mating involves differentiation of female reproductive structures (protoperithecia) and chemotropic growth of female-specific hyphae (trichogynes) towards a cell of the opposite mating type in a pheromone-mediated process. in this study, we characterize the pre-1 gene, encoding a predicted g-protein-coupled receptor with sequence similarity to fungal pheromone receptors. pre-1 is most highly expre ...200415186425
the bafilomycin/concanamycin binding site in subunit c of the v-atpases from neurospora crassa and saccharomyces cerevisiae.the vacuolar h+-atpase is inhibited with high specificity and potency by bafilomycin and concanamycin, macrolide antibiotics with similar structures. we previously reported that mutation at three residues in subunit c of the vacuolar atpase from neurospora crassa conferred strong resistance to bafilomycin but little or no resistance to concanamycin (bowman, b. j., and bowman, e. j. (2002) j. biol. chem. 277, 3965-3972). we have identified additional mutated sites in subunit c that confer resista ...200415180988
altering a gene involved in nuclear distribution increases the repeat-induced point mutation process in the fungus podospora anserina.repeat-induced point mutation (rip) is a homology-dependent gene-silencing mechanism that introduces c:g-to-t:a transitions in duplicated dna segments. cis-duplicated sequences can also be affected by another mechanism called premeiotic recombination (pr). both are active over the sexual cycle of some filamentous fungi, e.g., neurospora crassa and podospora anserina. during the sexual cycle, several developmental steps require precise nuclear movement and positioning, but connections between rip ...200415166143
properties of unpaired dna required for efficient silencing in neurospora crassa.the presence of unpaired copies of a gene during meiosis triggers silencing of all copies of the gene in the diploid ascus cell of neurospora. this phenomenon is called meiotic silencing and on the basis of genetic studies appears to be a post-transcriptional gene silencing (ptgs) mechanism. previously, meiotic silencing was defined to be induced by the presence of a dna region lacking an identical segment in the homologous chromosome. however, the determinants of unpaired dna remained a mystery ...200415166142
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