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a genetic selection for circadian output pathway mutations in neurospora crassa.in most organisms, circadian oscillators regulate the daily rhythmic expression of clock-controlled genes (ccgs). however, little is known about the pathways between the circadian oscillator(s) and the ccgs. in neurospora crassa, the frq, wc-1, and wc-2 genes encode components of the frq-oscillator. a functional frq-oscillator is required for rhythmic expression of the morning-specific ccg-1 and ccg-2 genes. in frq-null or wc-1 mutant strains, ccg-1 mrna levels fluctuate near peak levels over th ...200415166141
calcium measurement in living filamentous fungi expressing codon-optimized aequorin.calcium signalling is little understood in filamentous fungi largely because easy and routine methods for calcium measurement in living hyphae have previously been unavailable. we have developed the recombinant aequorin method for this purpose. high levels of aequorin expression were obtained in neurospora crassa, aspergillus niger and aspergillus awamori by codon optimization of the aequorin gene. three external stimuli (mechanical perturbation, hypo-osmotic shock and high external calcium) wer ...200415165245
alternative splicing of transcripts of the transposon restless is maintained in the foreign host neurospora crassa and can be modified by introducing mutations at the 5' and 3' splice sites.the primary transcript of the transposon restless from tolypocladium inflatum undergoes an unusual mechanism of alternative splicing by employing either of two 3' "cag" splice sites. these are separated by only four nucleotides, thus generating two different splice products, which differ in their coding capacity. to analyse whether this alternative splicing occurs in its natural host exclusively, we introduced the transposon into the heterologous host neurospora crassa. in addition to the wild - ...200415148624
identification of cryptochrome dash from vertebrates.a new type of cryptochrome, cry-dash, has been recently identified. the cry-dash proteins constitute the fifth subfamily of the photolyase/cryptochrome family. cry-dashs have been identified from synechocystis sp. pcc 6803, vibrio cholerae, and arabidopsis thaliana. the synechocystis cry-dash was the first cryptochrome identified from bacteria, and its biochemical features and tertiary structure have been extensively investigated. to determine how broadly the subfamily is distributed within livi ...200415147276
the neurospora crassa cfp promoter drives a carbon source-dependent expression of transgenes in filamentous fungi.the objective of the present study was to determine the potential of promoter sequences from the cfp gene of neurospora crassa to drive the expression of transgenes in filamentous fungi.200415139917
gadolinium effects on gigaseal formation and the adhesive properties of a fungal amoeboid cell, the slime mutant of neurospora crassa.low gadolinium concentrations induce rapid gigaseal formation and cell adhesion to glass and plastic (polystyrene) substrates in the slime mutant of neurospora crassa. cellular adhesion is independent of an integrin-mediated mechanism, because pretreatment with the oligopeptide arg-gly-asp-ser (rgds) did not inhibit it, and there was no spatial correlation between integrin and adhesions. in contrast, concanavalin a and beta-galactosidase both inhibit adhesion, suggesting that adhesion is mediate ...200415138747
the fluffy gene of neurospora crassa is necessary and sufficient to induce conidiophore development.the fl (fluffy) gene of neurospora crassa encodes a binuclear zinc cluster protein that regulates the production of asexual spores called macroconidia. two other genes, acon-2 and acon-3, play major roles in controlling development. fl is induced specifically in differentiating tissue during conidiation and acon-2 plays a role in this induction. we examined the function of fl by manipulating its level of expression in wild-type and developmental mutant strains. increasing expression of fl from a ...200415126394
the rna-dependent rna polymerase, qde-1, is a rate-limiting factor in post-transcriptional gene silencing in neurospora crassa.the rna-dependent rna polymerase (rdrp) qde-1 is an essential component of post-transcriptional gene silencing (ptgs), termed 'quelling' in the fungus neurospora crassa. here we show that the overexpression of qde-1 results in a dramatic increase in the efficiency of quelling, with a concomitant net increase in the quantity of al-1 sirnas. moreover, in overexpressed strains there is a significant reduction in the number of transgenes required to induce quelling, and an increase in the phenotypic ...200415090622
severe impairment of growth and differentiation in a neurospora crassa mutant lacking all heterotrimeric g alpha proteins.heterotrimeric g alpha proteins play a critical role in regulating growth and differentiation in filamentous fungi. no systematic analysis of functional relationships between subunits has been investigated. this study explores the relative contributions of neurospora crassa g alpha subunits, gna-1, gna-2, and gna-3, in directing development by analyzing strains deleted for various combinations of these genes. although viable, mutants lacking all g alpha subunits or gna-1 and gna-3 are severely r ...200415082543
[advances in the molecular mechanism of rna interference].this paper reviews the latest development of rna interference(rnai). rna interference is the process of sequence-specific degradation of homologous mrna triggered by double-stranded rna. as a technically simple and an effective genetic tool which can exert effect on the expression of gene and substitute for gene knock-out technique in some degree, rnai phenomena have been broadly validated in diverse model organisms such as caenorhabditis elegans, drosophila melanogaster, arabidopsis thaliana an ...200415079801
role of a mitogen-activated protein kinase pathway during conidial germination and hyphal fusion in neurospora crassa.mitogen-activated protein (map) kinase signaling pathways are ubiquitous and evolutionarily conserved in eukaryotic organisms. map kinase pathways are composed of a map kinase, a map kinase kinase, and a map kinase kinase kinase; activation is regulated by sequential phosphorylation. components of three map kinase pathways have been identified by genome sequence analysis in the filamentous fungus neurospora crassa. one of the predicted map kinases in n. crassa, mak-2, shows similarity to fus3p a ...200415075265
identification and characterization of a nitrate transporter gene in neurospora crassa.the neurospora crassa genome database was searched for sequence similarity to crna, a nitrate transporter in aspergillus nidulans. a 3.9-kb fragment (contig 3.416, subsequence 183190-187090) was cloned by pcr. the gene coding for this nitrate transporter was termed nit-10. the nit-10 gene specifies a predicted polypeptide containing 541 amino acids with a molecular mass of 57 kda. in contrast to crna, which is clustered together with niad, encoding nitrate reductase, and niia, encoding nitrite r ...200415068336
in vivo levels of s-adenosylmethionine modulate c:g to t:a mutations associated with repeat-induced point mutation in neurospora crassa.in neurospora crassa, the mutagenic process termed repeat-induced point mutation (rip) inactivates duplicated dna sequences during the sexual cycle by the introduction of c:g to t:a transition mutations. in this work, we have used a collection of n. crassa strains exhibiting a wide range of cellular levels of s-adenosylmethionine (adomet), the universal donor of methyl groups, to explore whether frequencies of rip are dependent on the cellular levels of this metabolite. mutant strains met-7 and ...200415063139
mammalian n-acetylglutamate synthase.n-acetylglutamate synthase (nags, e.c. 2.3.1.1) is a mitochondrial enzyme that catalyzes the formation of n-acetylglutamate (nag), an essential allosteric activator of carbamylphosphate synthetase i (cpsi). the mouse and human nags genes have been identified based on similarity to regions of nags from neurospora crassa and cloned from liver cdna libraries. these genes were shown to complement an arga- (nags) deficient escherichia coli strain, and enzymatic activity of the proteins was confirmed ...200415050968
oxygen flux magnitude and location along growing hyphae of neurospora crassa.oxygen fluxes were mapped at the growing apices and along mycelial hyphal segments of the ascomycete neurospora crassa. high spatial resolution was obtained using micro-oxygen probes (2-3 microm tip diameters) and the self-referencing technique to maximize the sensitivity of oxygen flux measurements. as expected, oxygen influx was inhibited by cyanide, although oxygen influx (and hyphal growth) resumed with the induction of an alternate oxidase activity. along hyphal segments, variations in oxyg ...200415043878
photoperiodism in neurospora crassa.plants and animals use day or night length for seasonal control of reproduction and other biological functions. overwhelming evidence suggests that this photoperiodic mechanism relies on a functional circadian system. recent progress has defined how flowering time in plants is regulated by photoperiodic control of output pathways, but the underlying mechanisms of photoperiodism remain to be described. the authors investigate photoperiodism in a genetic model system for circadian rhythms research ...200415038853
the neurospora crassa cyt-18 protein c-terminal rna-binding domain helps stabilize interdomain tertiary interactions in group i introns.the neurospora crassa mitochondrial tyrosyl-trna synthetase (cyt-18 protein) promotes the splicing of group i introns by stabilizing the catalytically active rna structure. to accomplish this, cyt-18 recognizes conserved structural features of group i intron rnas using regions of the n-terminal nucleotide-binding fold, intermediate alpha-helical, and c-terminal rna-binding domains that also function in binding trna(tyr). curiously, whereas the splicing of the n. crassa mitochondrial large subuni ...200415037773
entrainment dissociates transcription and translation of a circadian clock gene in neurospora.circadian systems coordinate the daily sequence of events in cells, tissues, and organisms. in constant conditions, the biological clock oscillates with its endogenous period, whereas it is synchronized to the 24 hr light:dark cycle in nature. here, we investigate light entrainment of neurospora crassa to photoperiods that mimic seasonal changes. clock gene (frequency, or frq) rna levels directly reflect the light environment in all photoperiods, whereas the frq protein follows neither rna level ...200415028220
incomplete penetrance and variable expressivity of a growth defect as a consequence of knocking out two k(+) transporters in the euascomycete fungus podospora anserina.we describe an example of incomplete penetrance and variable expressivity in the filamentous fungus podospora anserina, two genetic properties classically associated with mutations in more complex organisms, such as green plants and animals. we show that the knockouts of two trk-related k(+) transporters of this ascomycete present variability in their phenotype that cannot be attributed to fluctuations of the genetic background or the environment. thalli of the knockout strains derived from inde ...200415020412
sequence heterology and gene conversion at his-3 of neurospora crassa.although sequence heterology clearly reduces crossing over in yeast, conflicting studies suggest that mismatches may increase or decrease gene conversion. to investigate this issue in an additional species, we measured the effect of local sequence heterology on conversion in his-3 of neurospora crassa. mismatches close to the cog recombination initiator or within his-3 reduce conversion to 70% and 30% of the homologous level, respectively, while heterologous insertions between his-3 and cog incr ...200415007624
lessons from the genome sequence of neurospora crassa: tracing the path from genomic blueprint to multicellular organism.we present an analysis of over 1,100 of the approximately 10,000 predicted proteins encoded by the genome sequence of the filamentous fungus neurospora crassa. seven major areas of neurospora genomics and biology are covered. first, the basic features of the genome, including the automated assembly, gene calls, and global gene analyses are summarized. the second section covers components of the centromere and kinetochore complexes, chromatin assembly and modification, and transcription and trans ...200415007097
a sensitive predictor for potential gpi lipid modification sites in fungal protein sequences and its application to genome-wide studies for aspergillus nidulans, candida albicans, neurospora crassa, saccharomyces cerevisiae and schizosaccharomyces pombe.the fungal transamidase complex that executes glycosylphosphatidylinositol (gpi) lipid anchoring of precursor proteins has overlapping but distinct sequence specificity compared with the animal system. therefore, a taxon-specific prediction tool for the recognition of the c-terminal signal in fungal sequences is necessary. we have collected a learning set of fungal precursor protein sequences from the literature and fungal proteomes. although the general four segment scheme of the recognition si ...200415003443
identification of a novel gene hbrb required for polarised growth in aspergillus nidulans.we have cloned a novel gene, hbrb, by complementation of a temperature sensitive hyperbranching (hbr) mutant of aspergillus nidulans. the mutant, hbrb3, exhibits hyperseptation and shows a marked increase in hyphal branching at the restrictive temperature. a genomic library incorporating the ama1 sequence, which confers autonomous replication on the plasmid, was used to clone the gene. co-ordinate loss of the complementing plasmid and wild type phenotype was shown. the 847 amino acid predicted p ...200414998529
disruption of the gene encoding the v-atpase subunit a results in inhibition of normal growth and abolished sporulation in aspergillus nidulans.the authors have previously reported on molecular responses of aspergillus nidulans to bacterial antifungal metabolites, e.g. bafilomycins and the related concanamycins. these compounds are known inhibitors of v-atpases and cause dramatic effects on mycelial growth and morphology. in neurospora crassa, studies have shown that disruption of the gene encoding subunit a of the v-atpase results in morphological changes and reduced growth similar to those observed after addition of concanamycin. this ...200414993324
redundancy of the two dicer genes in transgene-induced posttranscriptional gene silencing in neurospora crassa.rna interference (rnai) in animals, cosuppression in plants, and quelling in fungi are homology-dependent gene silencing mechanisms in which the introduction of either double-stranded rna (dsrna) or transgenes induces sequence-specific mrna degradation. these phenomena share a common genetic and mechanistic basis. the accumulation of short interfering rna (sirna) molecules that guide sequence-specific mrna degradation is a common feature in both silencing mechanisms, as is the component of the r ...200414993290
molecular characterization of a penicillium chrysogenum exo-1,5-alpha-l-arabinanase that is structurally distinct from other arabinan-degrading enzymes.the nucleotide sequence of the abnx cdna gene, which encodes an exo-arabinanase (abnx) of penicillium chrysogenum 31b, was determined. abnx was found to be structurally distinct from known arabinan-degrading enzymes based on its amino acid sequence and a hydrophobic cluster analysis. the protein in the protein database with the highest similarity to abnx was the neurospora crassa conserved hypothetical protein. the abnx cdna gene product expressed in escherichia coli catalyzed the release of ara ...200414988022
hp1 is essential for dna methylation in neurospora.methylation of cytosines silences transposable elements and selected cellular genes in mammals, plants, and some fungi. recent findings have revealed mechanistic connections between dna methylation and features of specialized condensed chromatin, "heterochromatin." in neurospora crassa, dna methylation depends on trimethylation of lys9 in histone h3 by dim-5. heterochromatin protein hp1 binds methylated lys9 in vitro. we therefore investigated the possibility that a neurospora hp1 homolog reads ...200414967149
studies on the mechanism of reversion in biochemical mutants of neurospora crassa. 195114942745
aspects of the carbohydrate metabolism of a mutant of neurospora crassa requiring acetate for growth. 195214934248
two mutants of neurospora crassa which utilize formate or formaldehyde for growth. 195214927630
transaminases in neurospora crassa. 195114910611
neurospora diphosphopyridine nucleotidase. 195114861193
the effect of photoreactivation on mutation frequency in neurospora. 195114861174
a precursor of isoleucine obtained from a mutant strain of neurospora crassa. 195114841236
the enzymes of carbohydrate metabolism in neurospora. 1. succinic dehydrogenase. 195114838870
a gene that causes natural death in neurospora crassa. 195114823328
studies on the vitamin b6-requiring, ph-sensitive mutants of neurospora crassa. 195114811499
immunogenetic and biochemical studies of neurospora crassa: differences in tyrosinase activity between mating types of strain 15300 (albino-2). 195014808139
[transformation of kynurenin into nicotinic acid in the rat and in neurospora crassa]. 195014802985
the homology patterns of induced lethal mutations in neurospora crassa. 195014791473
heterokaryosis between opposite mating types of neurospora crassa. 195014791472
characterization of a valine analog accumulated by a mutant strain of neurospora crassa. 195014790819
an improved method for determination of p-aminobenzoic acid by neurospora crassa. 195014771898
the oxa2 protein of neurospora crassa plays a critical role in the biogenesis of cytochrome oxidase and defines a ubiquitous subbranch of the oxa1/yidc/alb3 protein family.proteins of the oxa1/yidc/alb3 family mediate the insertion of proteins into membranes of mitochondria, bacteria, and chloroplasts. here we report the identification of a second gene of the oxa1/yidc/alb3 family in the genome of neurospora crassa, which we have named oxa2. its gene product, oxa2, is located in the inner membrane of mitochondria. deletion of the oxa2 gene caused a specific defect in the biogenesis of cytochrome oxidase and resulted in induction of the alternative oxidase (aod), w ...200414767059
mate transposable elements in aspergillus nidulans: evidence of repeat-induced point mutation.the sequences of five mate transposable elements were retrieved from the aspergillus nidulans genome sequence. these elements are 6.1 kb in length and are characterized by 9-10 bp target site duplications, paired approximately 40 bp palindromes close to each end, and in the unmutated elements, 57 clustered spe-motifs (rwctagwy) scattered through their length. short open reading frames have no known homology. two of the mate elements have numerous c --> t transitions on both dna strands relative ...200414761791
comparative sequence analysis of sordaria macrospora and neurospora crassa as a means to improve genome annotation.one of the most challenging parts of large scale sequencing projects is the identification of functional elements encoded in a genome. recently, studies of genomes of up to six different saccharomyces species have demonstrated that a comparative analysis of genome sequences from closely related species is a powerful approach to identify open reading frames and other functional regions within genomes [science 301 (2003) 71, nature 423 (2003) 241]. here, we present a comparison of selected sequenc ...200414761789
cloning and characterization of the histidine kinase gene dic1 from cochliobolus heterostrophus that confers dicarboximide resistance and osmotic adaptation.a gene for a putative two-component histidine kinase, which is homologous to os-1 from neurospora crassa, was cloned and sequenced from the plant-pathogenic fungus cochliobolus heterostrophus. the predicted protein possessed the conserved histidine kinase domain, the response regulator domain, and six tandem repeats of 92-amino-acids at the n-terminal end that are found in histidine kinases from other filamentous fungi. introduction of the histidine kinase gene complemented the deficiency of the ...200414752661
the main external alternative nad(p)h dehydrogenase of neurospora crassa mitochondria.a dna sequence homologous to non-proton-pumping nadh dehydrogenase genes was found in the genome of neurospora crassa encoding a polypeptide of 577 amino acid residues, molecular mass of 64,656 da, with a putative transmembrane domain. analysis of fungal mitochondria fractionated with digitonin indicates that the protein is located at the outer face of the inner membrane of the organelle (external enzyme). the corresponding gene was inactivated by the generation of repeat-induced point mutations ...200414741584
cloning, sequencing and functional analysis of magnaporthe grisea mvp1 gene, a hex-1 homolog encoding a putative 'woronin body' protein.a hex-1 homolog named mvp1 was isolated from an appressoria cdna library of the rice blast fungus magnaporthe grisea. the transcript of approximately 1.6 kb contains 546 bp of coding sequence with a 3' untranslated region about 168 bp long and a 5' untranslated region about 870 bp long. southern gel blot analysis of genomic dna following digestion with three restriction enzymes (bamhi, ecori, hindiii) indicated that the gene exists as a single copy in m. grisea genome. rna gel blot analyses show ...200414734169
a mutation in the neurospora crassa actin gene results in multiple defects in tip growth and branching.actin has a pivotal function in hyphal morphogenesis in filamentous fungi, but it is not certain whether its function is equivalent to that of a morphogen, or if it is simply part of a mechanism that executes orders given by another regulatory entity. to address this question we selected for cytochalasin a resistance and isolated act1, the first actin mutant in neurospora crassa. this mutant branches apically and shows an altered distribution of actin at the tip. based on the properties of this ...200414732267
nuclear migration advances in fungi.nuclear migration encompasses three areas: separation of daughter nuclei during mitosis, congress of parental nuclei before they fuse during fertilization, and positioning of nuclei in interphase cells. this review deals primarily with interphase nuclear migration, which is crucial for events as disparate as vertebrate embryonic development and growth of fungal mycelia. mutants of aspergillus nidulans, neurospora crassa and saccharomyces cerevisiae have been particularly informative, and a detai ...199514732112
disruption of the aspergillus fumigatus argb gene using a novel in vitro transposon-based mutagenesis approach.we disrupted the aspergillus fumigatus argb gene, encoding ornithine transcarbamylase, using a novel in vitro transposon-based mutagenesis approach. this approach utilizes a modified transposon containing the neurospora crassa pyr4 gene, which is randomly inserted in vitro into a target sequence of interest. clones in which the gene of interest has been disrupted are identified by pcr and used to transform a pyrg-deficient strain of a. fumigatus. using this approach, we obtained arginine auxotro ...200414727059
the tim8-tim13 complex of neurospora crassa functions in the assembly of proteins into both mitochondrial membranes.the tim8 and tim13 proteins in yeast are known to exist in the mitochondrial intermembrane space and to form a hetero-oligomeric complex involved in the import of the mitochondrial inner membrane protein tim23, the central component of the tim23 translocase. here, we have isolated tim8 and tim13 mutants in neurospora crassa and have shown that mitochondria lacking the tim8-tim13 complex were deficient in the import of the outer membrane beta-barrel proteins tom40 and porin. cross-linking studies ...200414722057
role of two g-protein alpha subunits, tgaa and tgab, in the antagonism of plant pathogens by trichoderma virens.g-protein alpha subunits are involved in transmission of signals for development, pathogenicity, and secondary metabolism in plant pathogenic and saprophytic fungi. we cloned two g-protein alpha subunit genes, tgaa and tgab, from the biocontrol fungus trichoderma virens. tgaa belongs to the fungal galphai class, while tgab belongs to the class defined by gna-2 of neurospora crassa. we compared loss-of-function mutants of tgaa and tgab with the wild type for radial growth, conidiation, germinatio ...200414711686
reduced models of the circadian oscillators in neurospora crassa and drosophila melanogaster illustrate mechanistic similarities.we have developed a reduced model representing feedback loops of transcriptional regulation underlying circadian rhythms in neurospora crassa. the model contains two delay differential equations that describe the dynamics of two core gene products, frq and wcc. in a negative feedback loop, frq protein represses frq transcription by binding the white-collar complex (wcc), which consists of the wc-1 and wc-2 proteins. in a positive feedback loop, wcc indirectly enhances its own formation. the mode ...200314683608
mips: analysis and annotation of proteins from whole genomes.the munich information center for protein sequences (mips-gsf), neuherberg, germany, provides protein sequence-related information based on whole-genome analysis. the main focus of the work is directed toward the systematic organization of sequence-related attributes as gathered by a variety of algorithms, primary information from experimental data together with information compiled from the scientific literature. mips maintains automatically generated and manually annotated genome-specific data ...200414681354
gene organization and molecular modeling of copper amine oxidase from aspergillus niger: re-evaluation of the cofactor structure.amine oxidase ao-i from aspergillus niger aku 3302 has been reported to contain topa quinone (tpq) as a cofactor; however, analysis of the p-nitrophenylhydrazine-derivatized enzyme and purified active site peptides showed the presence of a carboxylate ester linkage of tpq to a glutamate. the catalytic functionality of such a cross-linked cofactor has recently been shown unlikely by spectroscopic and voltammetric studies on synthesized model compounds. we have obtained resonance raman spectra of ...200314669988
cloning, heterologous expression, and characterization of thielavia terrestris glucoamylase.thielavia terrestris is a soil-borne thermophilic fungus whose molecular/ cellular biology is poorly understood. only a few genes have been cloned from the thielavia genus. we detected an extracellular glucoamylase in culture filtrates of t. terrestris and cloned the corresponding glaa gene. the coding region contains five introns. based on the amino acid sequence, the glucoamylase was 65% identical to neurospora crassa glucoamylase. sequence comparisons suggested that the enzyme belongs to the ...200314665735
whole-genome analysis of two-component signal transduction genes in fungal pathogens.two-component phosphorelay systems are minimally comprised of a histidine kinase (hk) component, which autophosphorylates in response to an environmental stimulus, and a response regulator (rr) component, which transmits the signal, resulting in an output such as activation of transcription, or of a mitogen-activated protein kinase cascade. the genomes of the yeasts saccharomyces cerevisiae, schizosaccharomyces pombe, and candida albicans encode one, three, and three hks, respectively. in contra ...200314665450
purification, characterization and functional cloning of inositol oxygenase from cryptococcus.the enzyme inositol oxygenase (myo-inositol : oxygen oxidoreductase; e.c. 1.13.99.1) is a monooxygenase that converts inositol into glucuronic acid in the presence of molecular oxygen. this enzyme is integrated into a pathway leading to either degradation and energy production or the biosynthesis of precursors for polysaccharides. the enzyme was purified from the yeast cryptococcus lactativorus by a five-step chromatography procedure. the purified enzyme shows a molecular mass of 37 kda on sds-p ...200314663824
fungal proteomics: mapping the mitochondrial proteins of a trichoderma harzianum strain applied for biological control.mitochondria are essential for cellular functions across organisms. a proteomic approach was taken to separate and identify mitochondrial proteins from a strain of trichoderma harzianum with well established biocontrol properties. we optimized a method for the preparation of a sample enriched with mitochondria by ensuring efficient cell lysis and including several washing steps to minimize cytoplasmic contamination. we separated hundreds of proteins, using two-dimensional gel electrophoresis and ...200414652694
guest, a transposable element belonging to the tc1/mariner superfamily is an ancient invader of neurospora genomes.guest is a transposable element of the tc1/mariner superfamily with 30-40bp terminal inverted repeats and a ta dinucleotide target site duplication. guest was originally discovered in the st. lawrence 74a laboratory strain of the filamentous fungus neurospora crassa. in this report, guest iterations subcloned from a cosmid library of the oakridge 74a strain were used to design pcr primers that permitted the detection of guest in wild isolates of n. crassa. guest is present in n. crassa as multip ...200414643259
contig assembly and microsynteny analysis using a bacterial artificial chromosome library for epichloë festucae, a mutualistic fungal endophyte of grasses.we constructed and characterized a bacterial artificial chromosome (bac) library for epichloë festucae, a genetically tractable fungal plant mutualist. the 6144 clone library with an average insert size of 87kb represents at least 18-fold coverage of the 29 mb genome. we used the library to assemble a 110kb contig spanning the putative ornithine decarboxylase (odc) ortholog and subsequently expanded it to 228kb with a single walking step in each direction. furthermore, we evaluated conservation ...200414643256
extreme nuclear disproportion and constancy of enzyme activity in a heterokaryon of neurospora crassa.heterokaryons of neurospora crassa were generated by transformation of multinucleate conidia of a histidine-3 auxotroph with his-3(+) plasmid. in one of the transformants, propagated on a medium with histidine supplementation, a gradual but drastic reduction occurred in the proportion of prototrophic nuclei that contained an ectopically integrated his-3(+) allele. this response was specific to histidine. the reduction in prototrophic nuclei was confirmed by several criteria: inoculum size test, ...200614631094
reactive oxygen species affect photomorphogenesis in neurospora crassa.in neurospora crassa, several biological phenomena such as the synthesis of carotenoids in the mycelia and polarity of perithecia are regulated by light. we found that a sod-1 mutant, with a defective cu,zn-type superoxide dismutase (sod), showed accelerated light-dependent induction of carotenoid accumulation in the mycelia compared with the wild type. the initial rate of light-induced carotenoid accumulation in the sod-1 mutant was faster than that in the vvd mutant known to accumulate high co ...200414625272
photoreception in neurospora: a tale of two white collar proteins.neurospora crassa is the best-understood fungal organism in terms of the mechanism of light responses. all known neurospora photoresponses are mediated by blue light. two per-arnt-simdomain containing transcription factors, white collar-1 (wc-1) and wc-2, are essential components for almost all light responses. recently, wc-1was shown to be a blue-light photoreceptor. how light affects the dna binding of the wc proteins to the promoter of the circadian clock gene frequency was also demonstrated. ...200314618260
time series analysis demonstrates the absence of pulsatile hyphal growth.hyphal tip growth has been previously reported as pulsatile, defined as regularly alternating fast and slow rates of extension. the growth of pollen tubes, and hyphae of neurospora crassa and saprolegnia ferax were analysed using high spatial and temporal resolution. by using long (100-500 s) records of growth rate, sampled every second, it was possible to apply rigorous statistical analysis of the time series. as previously demonstrated, pollen tubes can show pulsatile growth, detectable with t ...200314600223
two divergent plasma membrane syntaxin-like snares, nsyn1 and nsyn2, contribute to hyphal tip growth and other developmental processes in neurospora crassa.highly polarized exocytosis of vesicles at hyphal apices is an essential requirement of tip growth. this requirement may be met by the localization and/or activation of an apical snare-based machinery. we have cloned nsyn1 and nsyn2, snares predicted to function at the plasma membrane in neurospora crassa. transformation of extra copies of nsyn1 into wild-type strains displayed effects consistent with quelling of nsyn1 expression, which was lethal in most transformants. all surviving transforman ...200314599895
interaction of mutations affecting tip growth and branching in neurospora.there are at least 100 loci encoding products that influence tip growth and branching in neurospora crassa. the functional relationships between 38 of these loci were examined by an analysis of gene interaction in double mutants. a complex range of interactions was revealed. these have been grouped into full and partial epistasis, costasis, novel phenotypes, and synthetic lethality and sublethality. epistasis was used to construct the simplest "pathway" that accommodated the results; this pathwa ...200314599894
analysis of nutrient-dependent transcript variations in neurospora crassa.nutrient-dependent variations in transcript levels of the filamentous fungus neurospora crassa were studied on a microarray containing some 4700 cdnas. cells were grown in minimal and acetate medium. the isolated rna was analyzed in comparison to the results obtained upon the hybridization of samples prepared from the rna of cells grown in full medium. altogether, 160 cdna clones exhibited significant variations, falling into five distinct subgroups of very similar transcription profiles. this i ...200314599890
mapping and characterization of polymorphism in mtdna of cryphonectria parasitica: evidence of the presence of an optional intron.the mitochondrial dna (mtdna) of the filamentous ascomycete cryphonectria parasitica is large and polymorphic so, to better understand the nature of the polymorphisms within populations, a small collection of italian strains of the fungus was examined. known mtdna polymorphisms were mapped and found to cluster in four regions of the mtdna molecule, particularly in the rflp region 2 where five different mtdna haplotypes out of 13 strains were identified. this region included an area of 8.4kbp whi ...200314599889
multiple oscillators regulate circadian gene expression in neurospora.high-density microarrays were used to profile circadian gene expression in neurospora crassa cultures grown in constant darkness. we identified 145 clock-controlled genes (ccgs). the ccgs peaked in mrna accumulation at all phases of the day, with the majority peaking in the late night to early morning. the predicted or known functions of the ccgs demonstrate that the clock contributes to a wide range of cellular processes, including cell signaling, development, metabolism, and stress responses. ...200314597725
identification of a type-d feruloyl esterase from neurospora crassa.feruloyl esterases constitute an interesting group of enzymes that have the potential for use over a broad range of applications in the agri-food industries. in order to expand the range of available enzymes, we have examined the presence of feruoyl esterase genes present in the genome sequence of the filamentous fungus neurospora crassa. we have identified an orphan gene (contig 3.544), the translation of which shows sequence identity with known feruloyl esterases. this gene was cloned and the ...200414595525
the neurospora crassa mus-19 gene is identical to the qde-3 gene, which encodes a recq homologue and is involved in recombination repair and postreplication repair.an allele called mus-19 was identified by screening temperature-sensitive and mutagen-sensitive mutants of neurospora crassa. the mus-19 gene was genetically mapped to a region near the end of the right arm of linkage group i, where a recq homologue called qde-3 had been physically mapped in the neurospora database. complementation tests between the mus-19 mutant and the qde-3(rip) mutant showed that mus-19 and qde-3 were the same gene. the qde-3 genes of both mutants were cloned and sequenced; ...200414595518
arabidopsis ndk1 is a component of ros signaling by interacting with three catalases.plants sense various environmental stimuli and have specific signaling pathways to respond to these cues. we focused on light responsive components and found that ndks were phosphorylated specifically after red light irradiation in pisum sativum [tanaka et al. (1998) j. photochem. photobiol. b 45: 113] and after blue light irradiation in neurospora crassa [oda and hasunuma (1997) mol. gen. genet. 256: 593, ogura et al. (2001) j. biol. chem. 276: 21228]. we performed yeast two-hybrid screening us ...200314581623
silencing of hygromycin phosphotransferase (hph) gene during sexual cycle and its reversible inactivation in heterokaryon of neurospora crassa.we transformed wild-type neurospora crassa with hph gene encoding hygromycin phosphotransferase to obtain hygromycin-resistant (hygr) transformants and studied their behavior in the vegetative and sexual phases of growth. during vegetative growth in the absence of hygromycin, the hph gene was stable for at least three successive transfers with conidia. on the other hand, the behavior of the transformants in the sexual phase was different. the segregation of hph gene in the meiotic progeny was in ...200314570273
a novel binding protein for a member of cyp40-type cyclophilins: n.crassa cypbp37, a growth and thiamine regulated protein homolog to yeast thi4p.cyclophilins belong to the family of peptidyl-prolyl cis/trans isomerases (ppiases), which are ubiquitous and highly conserved enzymes capable of cis/trans isomerizing xaa-pro peptide bonds. members of the cyp40-type cyclophilins have originally been described as components of hormone receptor complexes. here, we describe nccyp41, a cyp40 ortholog from neurospora crassa, its expression in escherichia coli and subsequent purification. characterization of nccyp41 reveals that it is a heat shock pr ...200314568539
chromosome rearrangements in isolates that escape from het-c heterokaryon incompatibility in neurospora crassa.chromosomal rearrangement is implicated in human cancers and hereditary diseases. mechanisms generating chromosomal rearrangements may be shared by a variety of organisms. spontaneous chromosomal rearrangements, especially large deletions, take place at high frequency in isolates that escape from heterokaryon incompatibility in neurospora crassa. in this study, chromosomal rearrangements were detected in strains that had escaped from het-c heterokaryon incompatibility in n. crassa. a vc1 mutant ...200414564476
isolation and characterization of neurospora crassa mutants resistant to antifungal plant defensins.twenty-five neurospora crassa mutants obtained by chemical mutagenesis were screened for increased resistance to various antifungal plant defensins. plant defensin-resistant n. crassa mutants were further tested for their cross-resistance towards other families of structurally different antimicrobial peptides. two n. crassa mutants, termed mut16 and mut24, displaying resistance towards all plant defensins tested but not to structurally different antimicrobial peptides were selected for further c ...200314516770
the photolyase gene from the plant pathogen fusarium oxysporum f. sp. lycopersici is induced by visible light and alpha-tomatine from tomato plant.survival of irradiated spores from fusarium oxysporum with ultraviolet radiation (uv) was increased following exposition to visible light, indicating that this phytopathogenic fungus has a mechanism of photoreactivation able to counteract the lethal effects of uv. a genomic sequence containing the complete photolyase gene (phr1) from f. oxysporum was isolated by heterologous hybridisation with the neurospora crassa photolyase gene. the f. oxysporum phr1 cdna was isolated and expressed in a photo ...200314516768
nuclear dna degradation during heterokaryon incompatibility in neurospora crassa.many filamentous fungi are capable of undergoing conspecific hyphal fusion with a genetically different individual to form a heterokaryon. however, the viability of such heterokaryons is dependent upon vegetative (heterokaryon) incompatibility (het) loci. if two individuals undergo hyphal anastomosis, but differ in allelic specificity at one or more het loci, the fusion cell is usually compartmentalized and self-destructs. many of the microscopic features associated with vegetative incompatibili ...200314516765
active/de-active transition of respiratory complex i in bacteria, fungi, and animals.mammalian complex i (nadh:ubiquinone oxidoreductase) exists as a mixture of interconvertible active (a) and de-activated (d) forms. the a-form is capable of nadh:quinone-reductase catalysis, but not the d-form. complex i from the bacterium paracoccus denitrificans, by contrast, exists only in the a-form. this bacterial complex contains 32 fewer subunits than the mammalian complex. the question arises therefore if the structural complexity of complex i from higher organisms correlates with its ab ...200314507430
identification of a protective antigen of coccidioides immitis by expression library immunization.coccidioides immitis is a fungal pathogen of humans and is classified as a select agent. we have identified a new potential vaccine candidate for this pathogen using cdna expression library immunization (eli). a c. immitis spherule-phase cdna library containing 800-1000 genes was divided into 10 pools and each was tested for its protective capacity in balb/c mice against intraperitoneal challenge with 2500 arthroconidia of this dimorphic fungus. the most protective pool, designated pool 7, was f ...200314505918
isolation of nuclei of neurospora crassa. 196114491130
effect of sulphur compounds on the uptake of molybdenum by neurospora crassa. 196214490063
effect of molybednum toxicity on sulphur metabolism in neurospora crassa. 196214490062
genes influencing the conversion of citrulline to argininosuccinate in neurospora crassa. 196214479348
factors affecting increased production of tryptophan synthetase by a td mutant of neurospora crassa.matchett, william h. (university of california, san diego, la jolla, calif.) and john a. demoss. factors affecting increased production of tryptophan synthetase by a td mutant of neurospora crassa. j. bacteriol. 83:1294-1300. 1962.-mutant td 201 of neurospora crassa produces a tryptophan synthetase in significantly larger amount than the parental wild-type strain. evidence obtained in the present investigation indicates that tryptophan synthetase formation in this mutant is subject to end produc ...196214471055
the growth of niacin-requiring strains of neurospora crassa with normal and altered phospholipid compositions. 196214465137
permeability and metabolism of lactose in neurospora crassa.lester, g. (worcester foundation for experimental biology, shrewsbury, mass.), d. azzena, and o. hechter. permeability and metabolism of lactose in neurospora crassa. j. bacteriol. 84:217-227. 1962.-germinated conidia of neurospora crassa suspended in buffer take up lactose, and this uptake can be attributed to the intracellular accumulation and to the metabolism of lactose. the former process predominates initially, and the latter after a few hours of incubation. the accumulation of lactose app ...196214464364
purification and properties of an acid phosphomonoesterase from neurospora crassa. 196114460641
an alkaline phosphomonoesterase from neurospora crassa. 196114460640
nystatin binding by protoplasts and a particulate fraction of neurospora crassa, and a basis for the selective toxicity of polyene antifungal antibiotics. 196214456211
induction and repression of nitrate reductase in neurospora crassa.kinsky, stephen c. (washington university, st. louis, mo.). induction and repression of nitrate reductase in neurospora crassa. j. bacteriol. 82:898-904. 1961.-techniques are described for studying induced enzyme formation in neurospora crassa. the effects of various parameters (time, ph, nitrate concentration, etc.) on the induction of nitrate reductase were investigated. it was demonstrated that nh(4) (+), which is the end product of the metabolic sequence initiated by nitrate reductase, repre ...196114456210
effect of polyene antibiotics on protoplasts of neurospora crassa.kinsky, stephen c. (washington university, st. louis, mo.). effect of polyene antibiotics on protoplasts of neurospora crassa. j. bacteriol. 83:351-358. 1962.-the polyene antibiotics nystatin, amphotericin b, and filipin induced shrinkage of neurospora crassa protoplasts stabilized in sucrose. at low concentrations of filipin (5 mug per ml), or higher concentrations of nystatin and amphotericin b (20 mug per ml), shrinkage was followed by swelling and lysis (bursting) of protoplasts. the effect ...196214456209
alterations in the permeability of neurospora crassa due to polyene antibiotics.kinsky, stephen c. (washington university, st. louis, mo.). alterations in the permeability of neurospora crassa due to polyene antibiotics. j. bacteriol. 82:889-897. 1961.-thirty-three antibiotics and synthetic fungicides were examined for their effect on the growth and morphology of neurospora crassa. only the polyene antibiotics (nystatin, amphotericin b, and filipin) caused a decrease in the dry weight of mycelial mats, which was accompanied by the appearance of cytoplasmic constituents in t ...196114456208
complementation among histidine mutants of neurospora crassa. 196014448643
electron microscopy of neurospora crassa mycelia.the fine structure of vegetative mycelia of the filamentous ascomycete, neurospora crassa, has been investigated by the standard techniques of electron microscopy. addition of uranyl nitrate to the methacrylate-embedding medium minimized disruption of the specimens-an accident often observed in the preparation of microbial material. this report describes the presence of a chitinous polysaccharide wall containing fine fibrils embedded in a homogeneous matrix. a sinuate plasma membrane lies adjace ...195914445619
transaminase activity in neurospora crassa. ii. kinetic behavior of a phenylpyruvate transaminase. 195914444465
transaminase activity in neurospora crassa. i. purification and substrate specificity of a phenylpyruvate transaminase. 195914444464
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