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mips: a database for genomes and protein sequences.the munich information center for protein sequences (mips-gsf, neuherberg, germany) continues to provide genome-related information in a systematic way. mips supports both national and european sequencing and functional analysis projects, develops and maintains automatically generated and manually annotated genome-specific databases, develops systematic classification schemes for the functional annotation of protein sequences, and provides tools for the comprehensive analysis of protein sequence ...200211752246
the role of g protein alpha subunits in the infection process of the gray mold fungus botrytis cinerea.to identify signal transduction pathways of the gray mold fungus botrytis cinerea involved in host infection, we used heterologous hybridization and a polymerase chain reaction (pcr)-based approach to isolate two genes (bcg1 and bcg2) encoding alpha subunits of heterotrimeric gtp-binding proteins. both genes have homologues in other fungi: bcg1 is a member of the g alpha(i) class, whereas bcg2 has similarities to the magc gene of magnaporthe grisea and the gna-2 gene of neurospora crassa. revers ...200111763127
analysis of genes expressed during rice-magnaporthe grisea interactions.expressed sequence tag (est) analysis was applied to identify rice genes involved in defense responses against infection by the blast fungus magnaporthe grisea and fungal genes involved in growth within the host during a compatible interaction. a total of 511 clones was sequenced from a cdna library constructed from rice leaves (oryza sativa cv. nipponbare) infected with m. grisea strain 70-15 to generate 296 nonredundant ests. the sequences of 293 clones (57.3%) significantly matched national c ...200111763134
large scale analysis of sequences from neurospora crassa.after 50 years of analysing neurospora crassa genes one by one large scale sequence analysis has increased the number of accessible genes tremendously in the last few years. being the only filamentous fungus for which a comprehensive genomic sequence database is publicly accessible n. crassa serves as the model for this important group of microorganisms. the mips n. crassa database currently holds more than 16 mb of non-redundant data of the chromosomes ii and v analysed by the german neurospora ...200211792448
protein import into mitochondria.most mitochondrial proteins are encoded by the nuclear genome and thus have to be imported into mitochondria from the cytosol. protein translocation across and into the mitochondrial membranes is a multistep process facilitated by the coordinated action of at least four specialized translocation systems in the outer and inner membranes of mitochondria. the outer membrane contains one general translocase, the tom complex, whereas three distinct translocases are located in the inner membrane, whic ...200111798021
targeting vectors for gene diversification by meiotic recombination in neurospora crassa.we have constructed a pair of vectors, pdv2 and pdv3, that enable targeted insertion of exogenous dna into linkage group i of neurospora crassa at the his-3 locus. transplaced sequences are inserted between his-3 and the cog(l) recombination hot spot and include his-3 mutations that allow meiotic recombination initiated by cog(l) to be monitored. selection of correctly placed transforming dna is based on complementation between different his-3 alleles borne by the plasmids and transformation hos ...200211798282
the ham-2 locus, encoding a putative transmembrane protein, is required for hyphal fusion in neurospora crassa.somatic cell fusion is common during organogenesis in multicellular eukaryotes, although the molecular mechanism of cell fusion is poorly understood. in filamentous fungi, somatic cell fusion occurs during vegetative growth. filamentous fungi grow as multinucleate hyphal tubes that undergo frequent hyphal fusion (anastomosis) during colony expansion, resulting in the formation of a hyphal network. the molecular mechanism of the hyphal fusion process and the role of networked hyphae in the growth ...200211805054
the sterol c-14 reductase encoded by the neurospora crassa erg-3 gene: essential charged and polar residues identified by site-specific mutagenesis.sterol c-14 reductase catalyses the reduction of the delta(14,15) bond in intermediates in the sterol biosynthesis pathway using nadph as a cofactor. we have undertaken a systematic site-directed mutational analysis of all the conserved charged and potentially proton-donating residues of the sterol c-14 reductase from neurospora crassa. the effect of each mutation was determined using an in vivo assay based on the complementation of the corresponding n. crassa mutant ( erg-3). the non-complement ...200211810252
osmoregulation and fungicide resistance: the neurospora crassa os-2 gene encodes a hog1 mitogen-activated protein kinase homologue.neurospora crassa osmosensitive (os) mutants are sensitive to high osmolarity and therefore are unable to grow on medium containing 4% nacl. we found that os-2 and os-5 mutants were resistant to the phenylpyrrole fungicides fludioxonil and fenpiclonil. to understand the relationship between osmoregulation and fungicide resistance, we cloned the os-2 gene by using sib selection. os-2 encodes a putative mitogen-activated protein (map) kinase homologous to hog1 and can complement the osmosensitive ...200211823187
the oxa1 protein forms a homooligomeric complex and is an essential part of the mitochondrial export translocase in neurospora crassa.the oxa1 protein is a ubiquitous constituent of the inner membrane of mitochondria. oxa1 was identified in yeast as a crucial component of the protein export machinery known as the oxa translocase, which facilitates the integration of proteins from the mitochondrial matrix into the inner membrane. we have identified the neurospora crassa oxa1 protein which shows a sequence identity of 22% to the yeast homologue. despite the low level of identity, the function of the homologues is conserved as th ...200211823466
identification and characterization of novel cytochrome p450 genes from the white-rot basidiomycete, coriolus versicolor.using a reverse-transcription polymerase chain reaction (rt-pcr) technique, cytochrome p450 genes were cloned from the lignin-degrading basidiomycete, coriolus versicolor. one possible p450 gene was identified, which consisted of 1,672 nucleotides and a poly(a) tail and encoded a deduced protein containing 449 amino acids. the deduced amino acid sequence revealed the presence of the p450 heme-binding motif, strongly suggesting that this protein belongs to the p450 superfamily, then designated cy ...200211831480
the opposed effect of 5-azacytidine and light on the development of reproductive structures in neurospora crassa.blue light inhibits the formation of asexual cycle spores (conidia) and stimulates the development of the sexual (female) reproductive structures (protoperithecia) in the nitrogen-starved mycelium of neurospora crassa. the dna methylation inhibitor, 5-azacytidine (3-300 microm), opposed the effect of light by suppressing the protoperithecia formation and stimulating a conidiation. the addition of 300 microm 5-azacytidine inhibited protoperithecia formation in the dark-cultivated mycelium by abou ...200211841042
molecular dissection of alleles of the osmotic-1 locus of neurospora crassa.two-component histidine kinases of bacteria, plants, and fungi are involved in the regulation of intracellular events in response to changes in external environmental conditions. fungal histidine kinases play important roles in osmoregulation, in vivo and in planta virulence, and sensitivity to certain classes of antifungals. the osmotic-1 (os-1) locus of neurospora crassa encodes a predicted protein with homology to histidine kinases and appears to be an osmosensor. mutants of the os-1 locus ar ...200211848677
ds-like restless deletion derivatives occur in tolypocladium inflatum and two foreign hosts, neurospora crassa and penicillium chrysogenum.single copies of the transposon restless from tolypocladium inflatum were introduced into neurospora crassa and penicillium chrysogenum. excision of restless from its donor site was investigated in n. crassa and in p. chrysogenum using direct selective conditions. in n. crassa, forward selection was also analyzed. deleted restless elements were frequently obtained in addition to the expected complete removal of restless from its donor site. similar deleted elements were also identified in t. inf ...200211848679
trna-like recognition of group i introns by a tyrosyl-trna synthetase.the neurospora crassa mitochondrial tyrosyl-trna synthetase (cyt-18 protein) functions in splicing group i introns by promoting the formation of the catalytically active rna structure. previous work suggested that cyt-18 recognizes a conserved trna-like structure of the group i intron catalytic core. here, directed hydroxyl-radical cleavage assays show that the nucleotide-binding fold and c-terminal domains of cyt-18 interact with the expected group i intron cognates of the aminoacyl-acceptor st ...200211854463
mutants of the carotene cyclase domain of al-2 from neurospora crassa.phytoene synthase and carotene cyclase, two key enzymes in carotenoid biosynthesis, are encoded by two separate genes in bacteria and plants, but by a single bifunctional gene in fungi. the cyclase function has been demonstrated for the products of the genes crtyb from the basidiomycete xanthophyllomyces dendrorhous, and for carra and carrp from the zygomycetes phycomyces blakesleeanus and mucor circinelloides, respectively. these three genes are highly similar to al-2 from neurospora crassa. ta ...200211862485
the reverse transcriptase of the r2 non-ltr retrotransposon: continuous synthesis of cdna on non-continuous rna templates.r2 is a non-long terminal repeat (non-ltr) retrotransposon that inserts into the 28 s rrna genes of arthropods. the element encodes two enzymatic activities: an endonuclease that specifically cleaves the 28 s gene target site, and a reverse transcriptase (rt) that can use the 3' end of the cleaved dna to prime reverse transcription. r2 rt only utilizes rna templates that contain the 3' untranslated region of the r2 element as templates in this target primed reverse transcription (tprt) reaction. ...200211866511
control of cpnpg dna methylation by the kryptonite histone h3 methyltransferase.gene silencing in eukaryotes is associated with the formation of heterochromatin, a complex of proteins and dna that block transcription. heterochromatin is characterized by the methylation of cytosine nucleotides of the dna, the methylation of histone h3 at lysine 9 (h3 lys 9), and the specific binding of heterochromatin protein 1 (hp1) to methylated h3 lys 9 (refs 1-7). although the relationship between these chromatin modifications is generally unknown, in the fungus neurospora crassa, dna me ...200211898023
identification and characterization of the genes encoding the core histones and histone variants of neurospora crassa.we have identified and characterized the complete complement of genes encoding the core histones of neurospora crassa. in addition to the previously identified pair of genes that encode histones h3 and h4 (hh3 and hh4-1), we identified a second histone h4 gene (hh4-2), a divergently transcribed pair of genes that encode h2a and h2b (hh2a and hh2b), a homolog of the f/z family of h2a variants (hh2az), a homolog of the h3 variant cse4 from saccharomyces cerevisiae (hh3v), and a highly diverged h4 ...200211901114
fertile hypomorphic argonaute (ago1) mutants impaired in post-transcriptional gene silencing and virus resistance.transgene-induced post-transcriptional gene silencing (ptgs) results from specific degradation of rnas that are homologous with the transgene transcribed sequence. this phenomenon, also known as cosuppression in plants and quelling in fungi, resembles rna interference (rnai) in animals. indeed, cosuppression/quelling/rnai require related paz/piwi proteins (ago1/qde-2/rde-1), indicating that these mechanisms are related. unlike neurospora crassa qde-2 and caenorhabditis elegans rde-1 mutants, whi ...200211910010
evidence for dominant suppression of repeat-induced point mutation (rip) in crosses with the wild-isolated neurospora crassa strains sugartown and adiopodoume-7.a convenient assay to score repeat-induced point mutation (rip) in neurospora employs the erg-3 locus as a mutagenesis target. using this assay we screened 132 wild-isolated neurospora crassa strains for ability to dominantly suppress rip. rip was exceptionally inefficient in crosses with the wild isolates sugartown (p0854) and adiopodoume-7 (p4305), thereby suggesting the presence of dominant rip suppressors in these strains. in other experiments, we found no evidence for dominant rip suppressi ...200111910125
the fle1 gene encoding a c2h2 zinc finger protein co-ordinates male and female sexual differentiation in podospora anserina.the flexuosa (fle1-1) mutant, isolated in podospora anserina, displays vegetative defects and two antagonistic sexual phenotypes: it produces several 1000-fold fewer microconidia (male gametes) than the wild-type strain and, conversely, more abundant protoperithecia (female organs). cloning and sequencing of the fle1 gene and of cdna identified an open reading frame encoding a 382-amino-acid polypeptide with two c2h2 zinc finger motifs. the predicted fle1 protein shares 46% identity with the flb ...200211918811
evolution of the fot1 transposons in the genus fusarium: discontinuous distribution and epigenetic inactivation.to understand the evolution of fot1, a member of the pogo family widely dispersed in ascomycetes, we have performed a phylogenetic survey across the genus fusarium divided into six sections. the taxonomic distribution of fot1 is not homogeneous but patchy; it is prevalent in the fusarium oxysporum complex, absent in closely related sections, and found in five species from the most distant section martiella. multiple copies of fot1 were sequenced from each strain in which the element occurs. in t ...200211919292
transformation in heterokaryons of neurospora crassa is nuclear rather than cellular phenomenon.in neurospora crassa, multinucleate macroconidia are used for genetic transformation. the barrier for such a transformation can be either at the cell membrane level or at the nuclear membrane level. for assessment of these possibilities, a forced heterokaryon (containing two genetically marked nuclei and auxotrophic for histidine) of neurospora crassa was transformed with a plasmid containing his-3+ gene. the transformants, which could grow without histidine supplementation, were then resolved i ...200211927980
the dna damage response in filamentous fungi.the mechanisms used by fungal cells to repair dna damage have been subjects of intensive investigation for almost 50 years. as a result, the model yeasts schizosaccharomyces pombe and saccharomyces cerevisiae have led the way in yielding critical insights into the nature of the dna damage response. at the same time, largely through the efforts of etta kafer, hirokazu inoue, and colleagues, a substantial collection of aspergillus nidulans and neurospora crassa dna repair mutants has been identifi ...200211929209
a genetic map of blumeria graminis based on functional genes, avirulence genes, and molecular markers.a genetic map of the powdery mildew fungus, blumeria graminis f. sp. hordei, an obligate biotrophic pathogen of barley, is presented. the linkage analysis was conducted on 81 segregating haploid progeny isolates from a cross between 2 isolates differing in seven avirulence genes. a total of 359 loci were mapped, comprising 182 amplified fragment length polymorphism markers, 168 restriction fragment length polymorphism markers including 42 ltr-retrotransposon loci and 99 expressed sequence tags ( ...200211929213
quelling in neurospora crassa. 200211931228
functional analysis of the escherichia coli molybdopterin cofactor biosynthesis protein moea by site-directed mutagenesis.five moea mutants were generated by replacing some conserved amino acids of moea by site-directed mutagenesis. the mutants were assayed for the ability to restore in vivo nitrate reductase activity of the moea mutant escherichia coli jrg97 and in vitro neurospora crassa nit-1 nitrate reductase activity. the replacements asp59alagly60ala, asp259ala, pro298alapro301ala abolished the function of moea in mo-molybdopterin formation and stabilization, reflected in the inability to restore nitrate redu ...200211934270
cia30 complex i assembly factor: a candidate for human complex i deficiency?the human mitochondrial nadh:ubiquinone oxidoreductase (complex i), the first complex of the oxidative phosphorylation system, is composed of at least 42 subunits. little is known about the assembly process of these subunits into the mature complex. recently, two proteins in neurospora crassa have been found to be involved in the assembly of complex i. these proteins are not constituent parts of the mature complex but are associated with smaller intermediate complexes of the assembly process and ...200211935339
the structure of neurospora crassa 3-carboxy-cis,cis-muconate lactonizing enzyme, a beta propeller cycloisomerase.muconate lactonizing enzymes (mles) convert cis,cis-muconates to muconolactones in microbes as part of the beta-ketoadipate pathway; some also dehalogenate muconate derivatives of xenobiotic haloaromatics. there are three different mle classes unrelated by evolution. we present the x-ray structure of a eukaryotic mle, neurospora crassa 3-carboxy-cis,cis-muconate lactonizing enzyme (nccmle) at 2.5 a resolution, with a seven-bladed beta propeller fold. it is related neither to bacterial mles nor t ...200211937053
involvement of small rnas and role of the qde genes in the gene silencing pathway in neurospora.small rna molecules have been found to be specifically associated with posttranscriptional gene silencing (ptgs) in both plants and animals. here, we find that small sense and antisense rnas are also involved in ptgs in neurospora crassa. the accumulation of these rna molecules depends on the presence of functional qde-1 and qde-3 genes previously shown to be essential for gene silencing, but does not depend on a functional qde-2, indicating that this gene is involved in a downstream step of the ...200211937487
genes encoding chimeras of neurospora crassa erg-3 and human tm7sf2 proteins fail to complement neurospora and yeast sterol c-14 reductase mutants.the human gene tm7sf2 encodes a polypeptide (sr-1) with high sequence similarity to sterol c-14 reductase, a key sterol biosynthetic enzyme in fungi, plants and mammals. in neurospora and yeast this enzyme is encoded by the erg-3 and erg24 genes respectively. in an effort to demonstrate sterol c-14 reductase activity for sr-1 we constructed six recombinant genes coding for chimeras of the neurospora erg-3 and sr-1 protein sequences and tested them for complementation of the neurospora erg-3 muta ...200211937680
electrophoretic pattern of and amino acid incorporation in vitro into the insoluble mitochondrial protein of neurospora crassa wild type and mi-1 mutant. 196811945305
mitochondrial peptide chain elongation factors from neurospora crassa.two complementary peptide chain elongation factors (g and t) have been isolated from a mitochondrial 100,000 g supernatant. both factors are specific for 70 s ribosomes and can be crossed with t and g factors from e. coli.197011945348
 in the extracts of quercus pedunculata roots, the activities of 5-dehydroquinate hydro-lyase and shikimate: nadp oxydoreductase are eluted in the same fractions whatever separation procedures are used: chromatography on sephadex g 100, deae cellulose and hydroxylapatite, centrifugation in sucrose density gradient, disc electrophoresis. these results are closely related to those obtained on the aggregate of enzymes involved in the shikimate pathway in neurospora crassa. the molecular weight of th ...197111945772
oxygenases involved in thymine and thymidine metabolism in neurospora crassa. 197211946494
close correlation between antimycin titer and cytochrome b(t) content in mitochondria of chloramphenicol treated neurospora crassa. 197211946688
in vitro translation of mitochondrial dna from neurospora crassa. 197211946701
insulin inhibition of membrane-bound adenylate cyclase in neurospora crassa. 197311947065
aldosugar dehydrogenases from neurospora crassa partial purification and characterization of d-arabinose: nad dehydrogenase. 197311947073
specificity of mitochondrial and cytoplasmic ribosomes from neurospora crassa in poly-u dependent cell free systems. 196911947164
cycloheximide resistant amino acid incorporation into mitochondrial protein from neurospora crassa in vivo. 196911947193
ferrochelatase in wild-type and in cytoplasmic mutants of neurospora crassa. 196911947230
effects of radiation during space flight on microorganisms and plants on the biosatellite ii and gemini xi missions.the results of recent experiments with the lysogenic bacteria, escherichia coli and salmonella typhimurium, the bread mold neurospora crassa and the flowering plant tradescantia on the biosatellite ii and gemini xi missions will be summarized. in the lysogenic bacteria experiment (dr. rudolf h.t. mattoni, nus corporation) on the biosatellite ii mission significant effects of space flight were found on both growth rate and the induction of prophage. in that part of the neurospora experiment on bo ...196911949688
isolation and characterization of tightly coupled mitochondria from wild type and nap mutant neurospora crassa.a fast and reproducible procedure was elaborated for isolation of tightly coupled mitochondria from wild type and nap-mutant neurospora crassa cells harvested at different growth stages. the isolated mitochondrial preparations had controlled metabolic states and were tightly coupled, i.e., displayed good respiratory control and had close to the theoretically expected maximal adp/o ratios upon oxidation of krebs cycle intermediates and exogenous nadh. they contained the fully competent respirator ...200211952424
interaction of mitochondria with microtubules in the filamentous fungus neurospora crassa.the establishment and maintenance of the 3d structure of eukaryotic cells depends on active transport and positioning of organelles along cytoskeletal elements. the biochemical basis of these processes is only poorly understood. we analysed the interaction of mitochondria with microtubules in the filamentous fungus neurospora crassa. mitochondria were fluorescently labelled by expression of matrix-targeted green fluorescent protein. upon isolation, mitochondria collapsed to round spherical struc ...200211956324
kinetics of 5-enolpyruvylshikimate-3-phosphate synthase inhibition by glyphosate.the herbicide glyphosate (n-phosphonomethyl glycine) is a potent reversible inhibitor of the 5-enolpyruvylshikimate-3-phosphate (epsp) synthase activity of the purified arom multienzyme complex from neurospora crassa. inhibition of the epsp synthase reaction by glyphosate is competitive with respect to phosphoenolpyruvate, with k(i) 1.1 microm, and uncompetitive with respect to shikimate-3-phosphate. the kinetic patterns are consistent with a compulsory order sequential mechanism in which either ...198311968207
3-carboxy-cis,cis-muconate lactonizing enzyme from neurospora crassa: mad phasing with 80 selenomethionines.the structure of 3-carboxy-cis,cis-muconate lactonizing enzyme from neurospora crassa was determined at 3.0 a resolution. phase information was derived from a multiwavelength anomalous dispersion (mad) experiment conducted at three wavelengths using crystals of fully substituted selenomethionine protein. however, the structure determination was not routine owing to the relatively poor quality of the diffraction data and the large number of twofolds in the unit cell. eventually, 80 selenium sites ...200211976482
molecular and biochemical characterization of the neurospora crassa glycogen synthase encoded by the gsn cdna.glycogen synthases catalyze the transfer of a glucosyl moiety from a nucleotide phosphosugar to a nascent glycogen chain via an alpha1-->4 linkage. although many genes coding for glycogen synthases have been described, the enzymes from rabbit and yeast are the best characterized. the fungus neurospora crassa accumulates glycogen during exponential growth, and mobilizes it at the onset of stationary phase, or when placed at high temperature or starved for carbon. through a pcr methodology, the gs ...200211976968
minimal promoter for the nad+-specific glutamate dehydrogenase gene of neurospora crassa.the expression of the nad+-specific glutamate dehydrogenase (nad-gdh) gene of neurospora crassa is subject to catabolite repression. to identify the minimal sequence necessary for promoter function, the 5'-flanking region of the nad-gdh gene was screened for potential protein-binding sites. fragments of dna, containing sequences upstream from the atg initiation codon, were employed as probes of southwestern blots of total cellular protein from cells grown in media promoting repression and induct ...200211989713
cloning and characterization of vmaa, the gene encoding a 69-kda catalytic subunit of the vacuolar h+-atpase during alkaline ph mediated growth of aspergillus oryzae.screening of a cdna library constructed under alkaline ph mediated growth of aspergillus oryzae implicated a vacuolar h+-atpase gene (vmaa) as a putative candidate involved in alkaline ph adaptation. a. oryzae vmaa genomic dna extended to 2072 bp including three introns and encoded a protein of 605 amino acids. vmaap was homologous to vma-1p from neurospora crassa (71%), vma1p from saccharomyces cerevisiae (69%) and atp6a2 from human (49%). the vmaa cdna complemented s. cerevisiae v-atpase disru ...200212007818
[arg-13 is implicated in mitochondrial ornithine transport in neurospora crassa].arg-13 is a leaky mutation involved in arginine metabolism. a tight selection is developed using similar amount of lysine and ornithine replacing other nitrogen source in minimal medium. this selection strongly inhibits the growth of arg-13 under stringent sorbose/glucose condition but allows arg-13 to grow under spot test conditions. as ornithine is build up through mitochondrial ornithine biosynthesis and transport from cytoplasm to mitochondria, arg-13 is combined in genetic crosses with arg- ...199812016957
carnitine biosynthesis in neurospora crassa: identification of a cdna coding for epsilon-n-trimethyllysine hydroxylase and its functional expression in saccharomyces cerevisiae.the biosynthesis of l-carnitine in eukaryotic organisms was first elucidated in the ascomycete neurospora crassa. the first step of the pathway is catalysed by epsilon-n-trimethyllysine hydroxylase (tmlh), which converts epsilon-n-trimethyllysine into beta-hydroxy-n-epsilon-trimethyllysine in a reaction dependent on alpha-ketoglutarate, fe2+ and oxygen. here we report on the cloning of the n. crassa tmlh cdna and its functional expression in saccharomyces cerevisiae. the tmlh cdna contains an op ...200212023072
neurospora crassa catalases, singlet oxygen and cell differentiation.the morphogenetic transitions of the n. crassa asexual life cycle are responses to a hyperoxidant state in which probably singlet oxygen is generated. induction of catalase activity and catalase oxidation by singlet oxygen are consequences of this recurrent hyperoxidant state. here the biochemical properties and regulation of two large monofunctional catalases are reviewed, and a new catalase-peroxidase gene and activity is described. catalase-3 is associated to growing and catalase-1 to non-gro ...200612033445
a 3d model of the voltage-dependent anion channel (vdac).eukaryotic porins are a group of membrane proteins whose best known role is to form an aqueous pore channel in the mitochondrial outer membrane. as opposed to the bacterial porins (a large family of protein whose 3d structure has been determined by x-ray diffraction), the structure of eukaryotic porins (also termed vdacs, voltage-dependent anion-selective channels) is still a matter of debate. we analysed the secondary structure of vdac from the yeast saccharomyces cerevisiae, the fungus neurosp ...200212044860
identification, cloning and expression of the mouse n-acetylglutamate synthase gene.in ureotelic animals, n-acetylglutamate (nag) is an essential allosteric activator of carbamylphosphate synthetase i (cpsi), the first enzyme in the urea cycle. nag synthase (nags; ec 2.3.1.1) catalyses the formation of nag from glutamate and acetyl-coa in liver and intestinal mitochondria. this enzyme is supposed to regulate ureagenesis by producing variable amounts of nag, thus modulating cpsi activity. moreover, inherited deficiencies in nags have been associated with hyperammonaemia, probabl ...200212049647
disruption of iron-sulphur cluster n2 from nadh: ubiquinone oxidoreductase by site-directed mutagenesis.we have cloned and inactivated, by repeat-induced point mutations, the nuclear gene encoding the 19.3 kda subunit of complex i (ec 1.6.5.3) from neurospora crassa, the homologue of the bovine psst polypeptide. mitochondria from mutant nuo19.3 lack the peripheral arm of complex i while its membrane arm accumulates. transformation with wild-type cdna rescues this phenotype and assembly of complex i is restored. to interfere with assembly of a proposed bound iron-sulphur cluster, site-directed muta ...200212049648
toeprint analysis of the positioning of translation apparatus components at initiation and termination codons of fungal mrnas.the ability to map the position of ribosomes and their associated factors on mrnas is critical for an understanding of translation mechanisms. earlier approaches to monitoring these important cellular events characterized nucleotide sequences rendered nuclease-resistant by ribosome binding. while these approaches furthered our understanding of translation initiation and ribosome pausing, the pertinent techniques were technically challenging and not widely applied. here we describe an alternative ...200212054887
the many faces of histone lysine methylation.diverse post-translational modifications of histone amino termini represent an important epigenetic mechanism for the organisation of chromatin structure and the regulation of gene activity. within the past two years, great progress has been made in understanding the functional implications of histone methylation; in particular through the characterisation of histone methyltransferases that direct the site-specific methylation of, for example, lysine 9 and lysine 4 positions in the histone h3 am ...200212067650
[superoxide dismutase and catalase activities in carotenoid-synthesizing fungi blakeslea trispora and neurospora crassa under the oxidative stress].the addition of menadione into the medium during cultivation of neurospora crassa in the dark activated its constitutive superoxide dismutase. exposure to light not only activated superoxide dismutase and catalase, but also increased the content of neurosporaxanthin. superoxide dismutase activity in the mixed (+/-) mycelium of blakeslea trispora synthesizing beta-carotene in the dark was much lower than that in neurospora crassa. the superoxide dismutase activity further decreased in oxidative s ...201312068573
circadian period lengths of lipid synthesis mutants (cel, chol-1) of neurospora show defective temperature, but intact ph-compensation.the influence of extracellular ph on the circadian sporulation rhythm of neurospora crassa has been investigated for the mutants chol-1 and cel. both mutants have a defect in the lipid synthesis pathway and require either choline or palmitate, respectively, as supplements for normal growth. the chol-1 and cel mutants also show an impaired temperature-compensation when growing on minimal medium. we investigated the possible correlation between loss of temperature- and ph-compensation in cel and c ...200212069035
multilocus self-recognition systems in fungi as a cause of trans-species polymorphism.trans-species polymorphism, meaning the presence of alleles in different species that are more similar to each other than they are to alleles in the same species, has been found at loci associated with vegetative incompatibility in filamentous fungi. if individuals differ at one or more of these loci (termed het for heterokaryon), they cannot form stable heterokaryons after vegetative fusion. at the het-c locus in neurospora crassa and related species there is clear evidence of trans-species pol ...200212072460
a cytosine methyltransferase homologue is essential for repeat-induced point mutation in neurospora crassa.during sexual development, neurospora crassa inactivates genes in duplicated dna segments by a hypermutation process, repeat-induced point mutation (rip). rip introduces c:g to t:a transition mutations and creates targets for subsequent dna methylation in vegetative tissue. the mechanism of rip and its relationship to dna methylation are not fully understood. mutations in dim-2, a dna methyltransferase (dmt) responsible for all known cytosine methylation in neurospora, does not prevent rip. we u ...200212072568
the upr-1 gene encodes a catalytic subunit of the dna polymerase zeta which is involved in damage-induced mutagenesis in neurospora crassa.the upr-1 mutant was one of the first mutagen-sensitive mutants to be isolated in neurospora crassa. however, the function of the upr-1 gene has not yet been elucidated, although some genetic and biochemical data have been accumulated. in order to clone the upr-1 gene, we performed a chromosome walk from the mat locus, the closest genetic marker to upr-1 for which a molecular probe was available, towards the centromere, and a chromosomal contig of about 300-400 kb was constructed. some of these ...200212073042
nht2, a copia ltr retrotransposon from a conditionally dispensable chromosome in nectria haematococca.in the plant pathogenic ascomycete nectria haematococca mating population (mp) vi, the conditionally dispensable chromosomes are unstable during sexual reproduction. during mapping of such a chromosome, three dispersed repeats were identified. nht2, one of these repeated elements, is a long terminal repeat (ltr) retrotransposon that is 5.9 kb in length. its deduced amino acid sequence is homologous to the four enzymatic domains characteristic of copia retrotransposons, but it contains multiple s ...200212073091
protein import into mitochondria of neurospora crassa.biogenesis of mitochondria requires import of several hundreds of different nuclear-encoded preproteins needed for mitochondrial structure and function. import and sorting of these preproteins is a multistep process facilitated by complex proteinaceous machineries located in the mitochondrial outer and inner membranes. the translocase of the mitochondrial outer membrane, the tom complex, comprises receptors which specifically recognize mitochondrial preproteins and a protein conducting channel f ...200212081461
mitochondrial dynamics in filamentous fungi.mitochondria are essential organelles of eukaryotic cells. they grow continuously throughout the cell cycle and are inherited by daughter cells upon cell division. inheritance of mitochondria and maintenance of mitochondrial distribution and morphology require active transport of the organelles along the cytoskeleton and depend on membrane fission and fusion events. many of the molecular components and cellular mechanisms mediating these complex processes have been conserved during evolution acr ...200212081462
functional analysis of the c6 zinc finger gene pro1 involved in fungal sexual development.the pro1 gene, controlling fruiting body development in the homothallic ascomycete sordaria macrospora, encodes a c6 zinc finger protein with a typical dna binding domain of gal4-like c6 zinc finger proteins as well as a putative nuclear targeting signal. in the corresponding mutant pro1, the pro1 gene is deleted, and the transition of primordia into mature fruiting bodies is prevented. to further characterize the pro1 polypeptide, the yeast system was used for identifying a transactivation doma ...200212081464
a dead-box protein functions as an atp-dependent rna chaperone in group i intron splicing.the neurospora crassa cyt-18 protein, the mitochondrial tyrosyl-trna synthetase, functions in splicing group i introns by inducing formation of the catalytically active rna structure. here, we identified a dead-box protein (cyt-19) that functions in concert with cyt-18 to promote group i intron splicing in vivo and vitro. cyt-19 does not bind specifically to group i intron rnas and instead functions as an atp-dependent rna chaperone to destabilize nonnative rna structures that constitute kinetic ...200212086675
white collar-1, a dna binding transcription factor and a light sensor.blue light regulates many physiological processes in fungi, but their photoreceptors are not known. in neurospora crassa, all light responses depend on the per-arnt-sim (pas) domain-containing transcription factor white collar-1 (wc-1). by removing the wc-1 light, oxygen, or voltage domain, a specialized pas domain that binds flavin mononucleotide in plant phototropins, we show that light responses are abolished, including light entrainment of the circadian clock. however, the wc-1-mediated dark ...200212098705
white collar-1, a circadian blue light photoreceptor, binding to the frequency promoter.in the fungus neurospora crassa, the blue light photoreceptor(s) and signaling pathway(s) have not been identified. we examined light signaling by exploiting the light sensitivity of the neurospora biological clock, specifically the rapid induction by light of the clock component frequency (frq). light induction of frq is transcriptionally controlled and requires two cis-acting elements (lres) in the frq promoter. both lres are bound by a white collar-1 (wc-1)/white collar-2 (wc-2)-containing co ...200212098706
domain movements of plasma membrane h(+)-atpase: 3d structures of two states by electron cryo-microscopy.h(+)-atpase is a p-type atpase that transports protons across membranes using the energy from atp hydrolysis. this hydrolysis is coupled to a conformational change between states of the protein, in which the proton-binding site is alternately accessible to the two sides of the membrane with an altered affinity. when isolated from neurospora crassa, h(+)-atpase is a 600 kda hexamer of identical 100 kda polypeptides. we have obtained the three-dimensional structures of both ligand-free and mg(2+)/ ...200212110571
light reception and circadian behavior in 'blind' and 'clock-less' mutants of neurospora crassa.the filamentous fungus neurospora crassa is a model organism for the genetic dissection of blue light photoreception and circadian rhythms. white collar-1 (wc-1) and wc-2 are considered necessary for all light responses, while frequency (frq) is required for light-regulated asexual development (conidia formation); without any of the three, self-sustained (circadian) rhythmicity in constant conditions fails. here we show that light-regulated and self-sustained development occur in the individual ...200212110577
interaction between mating-type proteins from the homothallic fungus sordaria macrospora.mating-type genes control sexual development in ascomycetes. little is known about their function in homothallic species, which are self-fertile and do not require a mating partner for sexual reproduction. the function of mating-type genes in the homothallic fungus sordaria macrospora was assayed using a yeast system in order to find properties typical of eukaryotic transcription factors. we were able to demonstrate that the mating-type proteins smta-1 and smta-1 have domains capable of activati ...200212111096
a regulator gene for acetate utilisation from neurospora crassa.the neurospora crassa homologue of the aspergillus nidulans regulatory gene facb has been cloned. the gene encodes a putative transcriptional activator of 865 amino acids that contains a dna-binding domain with a zn(ii)(2)cys(6) binuclear cluster, a linker region and a leucine zipper-like heptad repeat. two internal amino acid sequences are identical to peptide sequences determined from proteolytic fragments of a dna-binding protein complex specific for genes involved in acetate utilisation and ...200212111557
neurospora crassa supersuppressor mutants are amber codon-specific.neurospora crassa has 10 mapped supersuppressor (ssu) genes. in vivo studies indicate that they suppress amber (uag) premature termination mutations but the spectrum of their functions remains to be elucidated. we examined seven ssu strains (ssu-1, -2, -3, -4, -5, -9, and -10) using cell-free translation extracts. we tested suppression by requiring it to produce firefly luciferase from a reading frame containing premature uaa, uga, or uag terminators. all mutants except ssu-3 suppressed uag codo ...200212135572
an osmosensing histidine kinase mediates dicarboximide fungicide resistance in botryotinia fuckeliana (botrytis cinerea).a two-component histidine protein kinase gene, homologous to os-1 from neurospora crassa, was cloned and sequenced from a single ascospore isolate of botryotinia fuckeliana. a series of nine spontaneous mutants resistant to dicarboximide fungicides was selected from this strain and characterized with respect to fungicide resistance and osmotic sensitivity. genetic crosses of the mutants with an authentic daf1 strain showed that the phenotypes mapped to this locus. single point mutations (seven t ...200212135574
cloning and characterization of the gene encoding ribosomal p0 phosphoprotein from neurospora crassa.a gene for ribosomal protein p0 that belongs to the family of ribosomal p proteins was isolated from a neurospora crassa cdna library, using polyclonal antibodies against recombinant p0 protein from saccharomyces cerevisiae. this is the first gene for ribosomal p0 protein to be cloned from filamentous fungi. the derived p0 protein sequence has a strong homology to other eukaryotic p0 proteins; yet, there is a notable alteration in the conservative c-terminal region, placing this protein among th ...200212136931
cellular responses to environmental salinity in the halophilic black yeast hortaea werneckii.the development of crop plants with increased salt tolerance necessitates the study of naturally salt-tolerant eukaryotic species. we studied the bio-synthesis of glycerol as a compatible solute in the halophilic eukaryotic microorganism, black yeast hortaea werneckii. a restriction fragment-differential display technique was used to investigate the transcriptome of the organism. eight differentially expressed genes were identified in response to growth at different salinities. although the puta ...200212139614
the neurospora crassa pheromone precursor genes are regulated by the mating type locus and the circadian clock.pheromones play important roles in female and male behaviour in the filamentous ascomycete fungi. to begin to explore the role of pheromones in mating, we have identified the genes encoding the sex pheromones of the heterothallic species neurospora crassa. one gene, expressed exclusively in mat a strains, encodes a polypeptide containing multiple repeats of a putative pheromone sequence bordered by kex2 processing sites. strains of the opposite mating type, mat a, express a pheromone precursor g ...200212139624
regulation and oxidation of two large monofunctional catalases.the two neurospora crassa catalase genes cat-1 and cat-3 were shown to encode cat-1 and cat-3 large monofunctional catalases. cat-1 and cat-3 genes are regulated differentially during the asexual life cycle and under stress conditions. a stepwise increase in catalase activity occurs during conidiation. conidia have 60 times more catalase activity than exponentially growing hyphae. cat-1 activity was predominant in conidia, during germination and early exponential growth. it was induced during pr ...200212160934
cloning and expression of an endo-1,6-beta-d-glucanase gene (neg1) from neurospora crassa.a gene (neg1) encoding an endo-1,6-beta-d-glucanase from neurospora crassa was cloned. the putative neg1 was 1443-bp long and encoded a mature endo-1,6-beta-d-glucanase protein of 463 amino acids and signal peptide of 17 amino acids. the purified recombinant protein (neg1) obtained from escherichia coli showed 1,6-beta-d-glucanase activity. no genes similar in sequence were found in yeasts and fungi.200212162562
overexpression of white collar-1 (wc-1) activates circadian clock-associated genes, but is not sufficient to induce most light-regulated gene expression in neurospora crassa.many processes in fungi are regulated by light, but the molecular mechanisms are not well understood. the white collar-1 (wc-1) protein is required for all known blue-light responses in neurospora crassa. in response to light, wc-1 levels increase, and the protein is transiently phosphorylated. to test the hypothesis that the increase in wc-1 levels after light treatment is sufficient to activate light-regulated gene expression, we used microarrays to identify genes that respond to light treatme ...200212180913
blue light modulation of ion transport in the slime mutant of neurospora crassa.blue light is the primary entrainment signal for a number of developmental and morphological processes in the lower eucaryote neurospora crassa. blue light regulates photoactivation of carotenoid synthesis, conidiation, phototropism of perithecia and circadian rhythms. changes in the electrical properties of the plasma membrane are one of the fastest responses to blue light irradiation. to enable patch-clamp studies on light-induced ion channel activity, the wall-less slime mutant was used. patc ...200212181612
[effect of microbial elicitors on sclerotia biomass and carotenoid yield in surface cultures of penicillium sp.pt95].six kinds of elicitors were prepared respectively from neurospora crassa, monascus purpureus, sporobolomyces roseus, rhodotorula rubra, nocardia sp. n89 and actinoplanes sp. a05. when penicillium sp. pt95 was incubated in czapek's agar plates containing appropriate amounts of elicitors, both its sclerotia biomass and carotenoid content accumulated in sclerotia were enhanced significantly (p < 0.01). among tested elicitors, the elicitors from the fungi n. crassa, m. purpureus, s.-roseus and r. ru ...200212192877
from nadh to ubiquinone in neurospora mitochondria.the respiratory chain of the mitochondrial inner membrane includes a proton-pumping enzyme, complex i, which catalyses electron transfer from nadh to ubiquinone. this electron pathway occurs through a series of protein-bound prosthetic groups, fmn and around eight iron-sulfur clusters. the high number of polypeptide subunits of mitochondrial complex i, around 40, have a dual genetic origin. neurospora crassa has been a useful genetic model to characterise complex i. the characterisation of mutan ...200212206913
repeat-induced point mutation (rip) in magnaporthe grisea: implications for its sexual cycle in the natural field context.repeat-induced point mutation (rip) is a process that detects dna duplications and peppers their sequences with c:g to t:a transitions in the sexual phase of the life cycle. so far, this unique mechanism has been identified as a currently active process in only two fungal species, neurospora crassa and podospora anserina. to determine whether a rip-like process operates in the plant pathogenic fungus magnaporthe grisea, the retrotransposon maggy and the hygromycin b phosphotransferase gene were ...200212207702
the art and design of genetic screens: filamentous fungi.in the 1940s, screens for metabolic mutants of the filamentous fungus neurospora crassa established the fundamental, one-to-one relationship between a gene and a specific protein, and also established fungi as important genetic organisms. today, a wide range of filamentous species, which represents a billion years of evolutionary divergence, is used for experimental studies. the developmental complexity of these fungi sets them apart from unicellular yeasts, and allows the development of new scr ...200212209143
improving the efficiency of gene replacements in neurospora crassa: a first step towards a large-scale functional genomics project.here, we report the use of the mating type heterokaryon incompatibility system as a counterselection to increase the probability of identifying gene replacements in neurospora crassa. we compared the frequencies of gene replacements observed among transformants obtained by using plasmids with or without the mat a-1(+) gene (hereby called "toxic gene") placed adjacent to disruption cassettes. on an average, we were 20x more likely to identify a correct gene replacement by incorporating the toxic ...200212223190
the vea gene activates sexual development in aspergillus nidulans.the previously isolated gene complementing the vea1 mutation was confirmed to be the vea gene. the determined nucleotide sequence of the gene demonstrated that there is an open reading frame (orf) of a 573 amino acid polypeptide. the nucleotide sequence matched some clones of which functions were not assigned yet and the amino acid sequence matched that of neurospora crassa vea-related protein with 61% similarity. the nucleotide sequence of the vea1 mutant gene differed from that of the wild typ ...200212223191
live-cell imaging of vegetative hyphal fusion in neurospora crassa.the process of hyphal fusion (anastomosis) in growing colonies of neurospora crassa, stained with the membrane-selective dyes fm1-43 and fm4-64, was visualized by confocal microscopy. time-lapse, live-cell imaging illustrated the dynamics of hyphal growth and anastomosis during its pre-contact, contact and post-contact, and post-fusion stages. fusion-competent hyphae were morphologically distinct and exhibited remote sensing, resulting in branch initiation and/or re-direction of growth to facili ...200212223195
only the mature form of the plastidic chorismate synthase is enzymatically active.coding regions of a cdna for precursor and mature chorismate synthase (cs), a plastidic enzyme, from corydalis sempervirens were expressed in escherichia coli as translational fusions to glutathione-s-transferase. fusion proteins were purified, and precursor and mature forms of cs were then released by proteolytic cleavage with factor xa. although mature cs was enzymatically active after release, activity could be detected neither for the precursor cs nor for corresponding glutathione-s-transfer ...199512228531
nonself recognition is mediated by het-c heterocomplex formation during vegetative incompatibility.nonself recognition during vegetative growth in filamentous fungi is mediated by heterokaryon incompatibility (het) loci. in neurospora crassa, het-c is one of 11 het loci. three allelic specificity groups, termed het-c(or), het-c(pa) and het-c(gr), exist in natural populations. heterokaryons or partial diploids that contain het-c alleles of alternative specificity show severe growth inhibition, repression of conidiation and hyphal compartmentation and death (hcd). using epitope-tagged het-c, we ...200212234924
the hypocrea jecorina gal10 (uridine 5'-diphosphate-glucose 4-epimerase-encoding) gene differs from yeast homologues in structure, genomic organization and expression.as part of a comprehensive study on lactose metabolism in hypocrea jecorina (anamorph: trichoderma reesei), a genomic clone of the gal10 gene encoding h. jecorina uridine 5'-diphosphate (udp)-glucose 4-epimerase has been cloned and sequenced. it contains an open reading frame of 1548-base pair, interrupted by three introns, and encoding a 370-amino acids protein with similarity to pro- and eukaryotic udp-glucose-4-epimerases. h. jecorina gal10 does not contain the c-terminal mutarotase domain wh ...200212242021
identification of vib-1, a locus involved in vegetative incompatibility mediated by het-c in neurospora crassa.a non-self-recognition system called vegetative incompatibility is ubiquitous in filamentous fungi and is genetically regulated by het loci. different fungal individuals are unable to form viable heterokaryons if they differ in allelic specificity at a het locus. to identify components of vegetative incompatibility mediated by allelic differences at the het-c locus of neurospora crassa, we isolated mutants that suppressed phenotypic aspects of het-c vegetative incompatibility. three deletion mut ...200212242225
a new wc-1 mutant of neurospora crassa shows unique light sensitivity in the circadian conidiation rhythm.a new clock mutant ( rhy-2) was isolated by dna insertion mutagenesis using a plasmid that contains a region located upstream of the cmd gene in the genome of neurospora crassa. this mutant is arrhythmic with regard to conidiation in continuous darkness but rhythmic under a light-dark cycle. after plasmid rescue from genomic dna of the rhy-2 strain, the insertion was localized to the gene white collar-1 ( wc-1). plasmid dna was inserted 3' to the sequence encoding the polyglutamine region of the ...200212242499
mutants of chlamydomonas with aberrant responses to sulfur deprivation.in the absence of sulfur, chlamydomonas reinhardtii, a unicellular green alga, increases its rate of sulfate import and synthesizes several periplasmic proteins, including an arylsulfatase (ars). these changes appear to help cells acclimate to a sulfur-deficient environment. the elevated rate of sulfate import results from an increase in the capacity and affinity of the transport system for sulfate. the synthesis of ars, a periplasmic enzyme that cleaves sulfate from aromatic compounds, enables ...199412244220
a large ca2+-dependent channel formed by recombinant adp/atp carrier from neurospora crassa resembles the mitochondrial permeability transition pore.strong support for the central role of the adp/atp carrier (aac) in the mitochondrial permeability transition (mpt) is provided by the single-channel current measurements in patch-clamp experiments with the isolated reconstituted aac. in previous work [brustovetsky, n., and klingenberg, m. (1996) biochemistry 35, 8483-8488], this technique was applied to the aac isolated from bovine heart mitochondria. here we used recombinant aac (raac) from neurospora crassa expressed in e. coli, since aac fro ...200212269823
acyl derivatives of homoserine as substrates for homocysteine synthesis in neurospora crassa, yeast, and escherichia coli. 196712325384
a new class of tetraspanins in fungi.tetraspanins are animal proteins involved in membrane complexes that are involved in cell adhesion, differentiation, and motility. the pls1 gene from rice blast fungus magnaporthe grisea encodes a protein (pls1p) structurally related to tetraspanins that is required for pathogenicity. in botrytis cinerea public sequences, we identified an est homologous to pls1. using degenerated oligonucleotides, we amplified sequences homologous to pls1 in fungi colletotrichum lindemuthianum and neurospora cra ...200212372414
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