PMID(sorted descending)
interactions of chaperone alpha-crystallin with the molten globule state of xylose reductase. implications for reconstitution of the active enzyme.alpha-crystallin is a multimeric protein that has been shown to function as a molecular chaperone. present investigations were undertaken to understand its mechanism of chaperoning. for this functional in vitro analysis of alpha-crystallin we used xylose reductase (xr) from neurospora crassa as the model system. denaturation studies using the structure-perturbing agent guanidinium chloride indicated that xr folds through a partially folded state that resembles the molten globule. fluorescence an ...19989545266
molecular coevolution within a drosophila clock gene.the period (per) gene in drosophila melanogaster provides an integral component of biological rhythmicity and encodes a protein that includes a repetitive threonine-glycine (thr-gly) tract. similar repeats are found in the frq and wc2 clock genes of neurospora crassa and in the mammalian per homologues, but their circadian functions are unknown. in drosophilids, the length of the thr-gly repeat varies widely between species, and sequence comparisons have suggested that the repeat length coevolve ...19989539762
characterization of mat a-2, mat a-3 and deltamata mating-type mutants of neurospora crassa.the mating-type locus of neurospora crassa regulates mating identity and entry into the sexual cycle. the mat a idiomorph encodes three genes, mat a-1, mat a-2, and mat a-3. mutations in mat a-1 result in strains that have lost mating identity and vegetative incompatibility with mat a strains. a strain containing mutations in both mat a-2 and mat a-3 is able to mate, but forms few ascospores. in this study, we describe the isolation and characterization of a mutant deleted for mat (deltamata), a ...19989539425
the neurospora rca-1 gene complements an aspergillus flbd sporulation mutant but has no identifiable role in neurospora sporulation.the aspergillus nidulans flbd gene encodes a protein with a myb-like dna-binding domain that is proposed to act in concert with other developmental regulators to control initiation of conidiophore development. we have identified a neurospora crassa gene called rca-1 (regulator of conidiation in aspergillus) based on its sequence similarity to flbd. we found that n. crassa rca-1 can complement the conidiation defect of an a. nidulans flbd mutant and that induced expression of rca-1 caused conidia ...19989539422
characterization of the aspergillus nidulans nmra gene involved in nitrogen metabolite repression.the gene nmra of aspergillus nidulans has been isolated and found to be a homolog of the neurospora crassa gene nmr-1, involved in nitrogen metabolite repression. deletion of nmra results in partial derepression of activities subject to nitrogen repression similar to phenotypes observed for certain mutations in the positively acting area gene.19989537404
molecular genetics of mating recognition in basidiomycete fungi.the recognition of compatible mating partners in the basidiomycete fungi requires the coordinated activities of two gene complexes defined as the mating-type genes. one complex encodes members of the homeobox family of transcription factors, which heterodimerize on mating to generate an active transcription regulator. the other complex encodes peptide pheromones and 7-transmembrane receptors that permit intercellular signalling. remarkably, a single species may have many thousands of cross-compa ...19989529887
processing and function of a polyprotein precursor of two mitochondrial proteins in neurospora neurospora crassa, the mitochondrial arginine biosynthetic enzymes, n-acetylglutamate kinase (agk) and n-acetyl-gamma-glutamyl-phosphate reductase (agpr), are generated by processing of a 96-kda cytosolic polyprotein precursor (pagk-agpr). the proximal kinase and distal reductase domains are separated by a short connector region. substitutions of arginines at positions -2 and -3 upstream of the n terminus of the agpr domain or replacement of threonine at position +3 in the mature agpr domain ...19989525895
secondary structure of the intact h+,k+-atpase and of its membrane-embedded region. an attenuated total reflection infrared spectroscopy, circular dichroism and raman spectroscopy study.models of p-type atpase predict that membrane-embedded fragments represent about 20% of the protein and adopt an all-alpha-helical structure. while this prediction was confirmed for the ca2-atpase [corbalan-garcia, s., teruel, j., villalain, j. & gomez-fernandez, j. (1994) biochemistry 33, 8247-8254], it is at odds with recent experimental evidence gathered on the neurospora crassa plasma membrane h+-atpase [vigneron, l., ruysschaert, j.-m. & goormaghtigh, e. (1995) j. biol. chem. 270, 17685-176 ...19989523697
the role of the dynactin complex in intracellular motility.dynactin is a multisubunit complex that binds to the minus-end-directed microtubule motor cytoplasmic dynein and may provide a link between the motor and its cargo. results from genetic studies in saccharomyces cerevisiae, neurospora crassa, aspergillus nidulans, and drosophila have suggested that cytoplasmic dynein and dynactin function in the same cellular pathways. p150glued, a vertebrate homologue of the drosophila gene glued, is the largest polypeptide in the dynactin complex with multiple ...19989522459
inactivation of the gene coding for the 30.4-kda subunit of respiratory chain nadh dehydrogenase: is the enzyme essential for neurospora?we have isolated and characterised the nuclear gene that codes for the 30.4-kda subunit of the peripheral arm of complex i from neurospora crassa. the single-copy gene was localised on chromosome vi of the fungal genome by restriction fragment length polymorphism mapping. an extra copy of the gene was introduced into a strain of n. crassa by transformation. this strain was crossed with another strain in order to inactivate, by repeat-induced point mutations, both copies of the duplication carrie ...19989520272
the aspergillus nidulans sulphur regulatory gene sconb encodes a protein with wd40 repeats and an f-box.the aspergillus nidulans gene sconb, one of the four identified genes controlling sulphur metabolite repression, was cloned and analysed. it encodes a polypeptide of 678 amino acids containing seven wd repeats characteristic of the large wd40 family of eukaryotic regulatory proteins. the sconb protein has nuclear localisation signals and is very similar to the neurospora crassa scon2 and saccharomyces cerevisiae met30 proteins, both of which are involved in the regulation of sulphur metabolism. ...19989520259
consistent structure between bacterial and mitochondrial nadh:ubiquinone oxidoreductase (complex i).respiratory chains of bacteria and mitochondria contain closely related forms of the proton-pumping nadh:ubiquinone oxidoreductase (complex i). in bacteria the complex has a molecular mass of approximately 530 kda and consists of 14 different subunits. the homologues of these 14 subunits together with some 27 additional subunits make up the mitochondrial complex, adding up to a molecular mass of approximately 1 mda. we calculated three-dimensional models at medium resolution of isolated and nega ...19989514725
microscopic and ultrastructural examination of vegetative incompatibility in partial diploids heterozygous at het loci in neurospora crassavegetative (or heterokaryon) incompatibility is often characterized by cell death after anastomosis. in neurospora crassa, partial diploid strains heterozygous for a single heterokaryon incompatibility (het) gene are viable, but grow at a significantly inhibited rate. strains heterozygous for het-6 or het-c were examined microscopically for evidence of cell death; approximately 15% of cells randomly distributed within such colonies were dead or dying. electron microscopy revealed extensive organ ...19989514694
cloning and characterization of a general amino acid control transcriptional activator from the chestnut blight fungus cryphonectria parasitica.we have cloned and characterized a homologue of the neurospora crassa general amino acid control gene cpc-1 from the chestnut blight fungus cryphonectria parasitica. the deduced amino acid sequence of c. parasitica cpc1 (cpcpc1) contains regions with significant homology to the transcriptional activation, dna binding, and dimerization domains previously defined for n. crassa cpc1 (nccpc1) and the equivalent "b-zip" transcription factor from saccharomyces cerevisiae, gcn4 (scgcn4). treatment of c ...19989501479
purification, characterization, and mechanism of a flavin mononucleotide-dependent 2-nitropropane dioxygenase from neurospora crassa.a nitroalkane-oxidizing enzyme was purified to homogeneity from neurospora crassa. the enzyme is composed of two subunits; the molecular weight of each subunit is approximately 40,000. the enzyme catalyzes the oxidation of nitroalkanes to produce the corresponding carbonyl compounds. it acts on 2-nitropropane better than on nitroethane and 1-nitropropane, and anionic forms of nitroalkanes are much better substrates than are neutral forms. the enzyme does not act on aromatic compounds. when the e ...19989501443
isolation of casln1 and canik1, the genes for osmosensing histidine kinase homologues, from the pathogenic fungus candida albicans.recent studies have revealed that fungi possess a mechanism similar to bacterial two-component systems to respond to extracellular changes in osmolarity. in saccharomyces cerevisiae, sln1p contains both histidine kinase and receiver (response regulator) domains and acts as an osmosensor protein that regulates the downstream hog1 map kinase cascade. sln1 of candida albicans was functionally cloned using an s. cerevisiae strain in which sln1 expression was conditionally suppressed. deletion analys ...19989493379
a nima homologue promotes chromatin condensation in fission yeast.entry into mitosis requires p34(cdc2), which activates downstream mitotic events through phosphorylation of key target proteins. in aspergillus nidulans, the nima protein kinase has been identified as a potential downstream target and plays a role in regulating chromatin condensation at mitosis. nima- mutants arrest in a state that physically resembles interphase even though p34(cdc2) is fully active. despite evidence for the existence of nima-like activities in a variety of cell types, the only ...19989490640
carbon allocation in ectomycorrhizas: identification and expression analysis of an amanita muscaria monosaccharide transporter.ectomycorrhizas are formed between certain soil fungi and fine roots of predominantly woody plants. an important feature of this symbiosis is the supply of plant-derived carbohydrates to the fungus. as a first step toward a better understanding of the molecular basis of this process, we cloned a monosaccharide transporter from the ectomycorrhizal fungus amanita muscaria. degenerate oligonucleotide primers were designed to match conserved regions from known fungal sugar transporters. a cdna fragm ...19989487692
an additional role for the f-box motif: gene regulation within the neurospora crassa sulfur control network.the f-box represents a protein motif originally identified as a conserved amino-terminal domain within the neurospora crassa negative regulator sulfur controller-2. recently, f-boxes have been found within a number of cell cycle regulatory proteins, where they mediate ubiquitin-driven proteolytic events required for major cell cycle transitions. f-box function, however, is not restricted solely to cell cycle pathways. here we present evidence expanding f-box function to encompass gene regulatory ...19989482900
hypothesis--origin of the parietal cell: microorganism?parietal cells, which exist in the stomach and in meckel's diverticulum of the ileum, secrete hydrochloric acid by means of h+,k(+)-atpase (alpha- and beta-subunits) in the human body. although parietal cells are generated from progenitor cells (stem cells), their lifespan (approximately 150-200 days) is distinctly longer than that of surface epithelial cells (4 days), which are also derived from stem cells. microorganisms, including bacteria (both aerobic and anaerobic), are able to pump h+ out ...19979479641
the neurospora aab-1 gene encodes a ccaat binding protein homologous to yeast hap5.the expression of the am (glutamate dehydrogenase) gene is dependent upon two upstream activating sequences, designated ursam(alpha) and ursam(beta). a heteromeric nuclear protein am alpha binding protein (aab) binds specifically to a ccaat box within the ursam(alpha) element. aab appears to be composed of three components. we used polyclonal antiserum raised against the highly purified aab1 subunit to isolate a partial aab-1 cdna clone, which was then used to isolate a full-length cdna and a ge ...19989475726
long, interrupted conversion tracts initiated by cog in neurospora crassa.multiple polymorphisms distinguish emerson and lindegren strains of neurospora crassa within the histidine-3 gene and in its distal flank. restriction site and sequence length polymorphism in a set of 14 pcr products covering this 6.9-kb region were used to identify the parental origin of dna sequence information in prototrophic progeny of crosses heterozygous for auxotrophic mutations in his-3 and the silent sequence differences. forty-one percent of conversion tracts are interrupted. where the ...19989475725
bioelectrorheological model of the cell. 7. cellular deformation in the presence of cytochalasin b.the influence of cytochalasin b on the mechanical properties of neurospora crassa cells subjected to a periodic electric field was investigated. shear and extensional deformations were considered and studied separately. conditions were found under which shear deformations become irreversible. rheological models helped in the interpretation of the results in terms of the different response to the shear stress of the three hypothetical supramolecular regions of the membrane-skeleton network (f, s ...20139474262
differential expression of glucose-regulated (grp78) and heat-shock-inducible (hsp70) genes during asexual development of neurospora crassa.the expression of a glucose-regulated gene (grp78) changes significantly during the vegetative life cycle of neurospora crassa: the amounts of grp78 mrna are low in dormant conidia, increase during germination and exponential growth, decline in young aerial hyphae and reach a maximum in late (15-18 h) aerial hyphae. heat shock (30 min at 45 degrees c) elevated the mrna level of this gene especially in early aerial hyphae, whereas no increase above the high constitutive amount was found after hea ...19989467899
homology modeling of neurospora crassa geranylgeranyl pyrophosphate synthase: structural interpretation of mutant phenotypes.a model of the tertiary structure of the neurospora crassa carotenogenic prenyltransferase, geranylgeranyl pyrophosphate synthase (ggpps), is presented, based on structural homology with other prenyltransferases and on the crystal structure of recombinant avian farnesyl pyrophosphate synthase (fpps). the conserved aspartate-rich motifs ddxx(xx)d and associated basic residues, considered to be the active sites for binding and catalysis in all prenyltransferases, are highly conserved in the n. cra ...19979464568
recombinant pseudorabies virus dnase exhibits a recbcd-like catalytic function.the pseudorabies virus (prv) dnase gene has previously been mapped within the prv genome. to characterize further the enzymic properties of prv dnase, this enzyme was expressed in escherichia coli with the use of a pet expression vector. the protein was purified to homogeneity and assayed for nuclease activity in vitro. recombinant prv dnase exhibited an alkaline ph preference and an absolute requirement for mg2+ ions that could not be replaced by ca2+ and na+ ions. further studies showed that p ...19989461490
cloning and characterization of the gene encoding beta subunit of mitochondrial processing peptidase from the basidiomycete lentinula edodes.we have isolated the gene encoding the beta subunit of mitochondrial processing peptidase (beta-mpp) from the shiitake mushroom lentinula edodes. it is a nuclear gene with two small introns. comparison with known beta-mpp genes revealed that the l. edodes gene is most closely related with that from neurospora crassa, with 60.8% identities and 87% similarity in the amino-acid sequences. the deduced l. edodes beta-mpp peptide sequence contains the inverse zinc-binding motif (h-x-e-h) that has been ...19989461410
analysis of electrical phenomena accompanying the growth of neurospora crassa hyphae: theory and describe electrical phenomena observed in growth of neurospora crassa hyphae, a theoretical model was developed considering the hypha as a one-dimensional electric cable with non-uniform longitudinal distribution of current sources reflecting the activity of proton pumps. a profile of the density of the pump current along the hypha is proposed, at which the results of simulation quantitatively coincide with the results of physiological experiments. the model values of energy coupling in the g ...19979460054
synthesis and differential turnover of the cys3 regulatory protein of neurospora crassa are subject to sulfur control.the transcription factor cys3 of neurospora crassa is a positive regulator of the sulfur regulatory circuit which contains many structural genes involved in sulfur metabolism. expression and degradation of the cys3 protein are precisely regulated in a sulfur-dependent manner. cys-3 expression was found to be fully repressed by high concentrations of methionine or inorganic sulfate present in the culture medium and to be derepressed when these favored sulfur sources were limited. cys-3 transcript ...19989457847
umchs5, a gene coding for a class iv chitin synthase in ustilago maydis.a fragment corresponding to a conserved region of a fifth gene coding for chitin synthase in the plant pathogenic fungus ustilago maydis was amplified by means of the polymerase chain reaction (pcr). the amplified fragment was utilized as a probe for the identification of the whole gene in a genomic library of the fungus. the predicted gene product of umchs5 has highest similarity with class iv chitin synthases encoded by the chs3 genes from saccharomyces cerevisiae and candida albicans, chs-4 f ...19979454647
characterization of vacuolar arginine uptake and amino acid efflux in neurospora crassa using cupric ion to permeabilize the plasma membrane.treatment of neurospora crassa mycelia with cupric ion has been shown to permeabilize the plasma and mitochondrial membranes. permeabilized mycelia were shown to take up arginine into the vacuoles. uptake was atp-independent and appeared to be driven by an existing k+-gradient. the kinetic characteristics of the observed uptake were similar to those observed using vacuolar membrane vesicles: the km for arginine uptake was found to be 4.2-4.5 mm. permeabilized mycelia were used to study the regul ...19979454645
blue light regulation in neurospora crassa.the fungus neurospora crassa has been shown to be a paradigm for photobiological, biochemical, and genetic studies of blue light perception and signal transduction. several different developmental and morphological processes of neurospora are regulated by blue light and can be divided into early and late blue light responses. the characterization of two central regulator proteins of blue light signal transduction in neurospora crassa, wc1 and wc2, and the isolation of light-regulated genes, indi ...19979454641
identification of the tyky homologous subunit of complex i from neurospora crassa.a polypeptide subunit of complex i from neurospora crassa, homologous to bovine tyky, was expressed in escherichia coli, purified and used for the production of rabbit antiserum. the mature mitochondrial protein displays a molecular mass of 21280 da and results from cleavage of a presequence consisting of the first 34 n-terminal amino acids of the precursor. this protein was found closely associated with the peripheral arm of complex i.19979452770
effects of the tol mutation on allelic interactions at het loci in neurospora crassa.a mutant at the tol locus of neurospora crassa can suppress heterokaryon (vegetative) incompatibility associated with differences at the mating-type locus. we tested the ability of this allele to suppress the vegetative incompatibility reactions that can occur when strains differ at one of nine het loci (het-c, -d, -e, -5, -6, -7, -8, -9, and -10). we found no cases in which the tol mutant suppresses a heteroallelic het locus interaction. thus, the interaction(s) that leads to vegetative incompa ...19979449795
mating type in filamentous fungi.mating type genes regulate sexual compatibility and sexual reproduction in fungi. this review focuses on recent molecular analyses of well-characterized mating systems from representative ascomycete (neurospora crassa, podospora anserina) and basidiomycete (ustilago maydis, coprinus cinereus, schizophyllum commune) fungi. these mating systems include many conserved components, such as gene regulatory polypeptides and pheromone/receptor signal transduction cascades, as well as conserved processes ...19979442896
genetic analysis of signal transduction through light-induced protein phosphorylation in neurospora crassa perithecia.we have previously demonstrated that blue light induces the phosphorylation of a 15-kda protein in crude membrane fractions of neurospora crassa mycelia. here we report the isolation and characterization of a mutant (psp; phosphorylation of small proteins that is completely defective for phosphorylation of that protein, as assayed in both crude membrane and soluble fractions. this mutation defines a unique locus that maps to linkage group vr between al-3 and his-6. to elucidate the photobiologic ...19979435784
two distinct protein-protein interactions between the nit2 and nmr regulatory proteins are required to establish nitrogen metabolite repression in neurospora crassa.nitrogen metabolism is a highly regulated process in neurospora crassa. the structural genes that encode nitrogen catabolic enzymes are subject to nitrogen metabolite repression, mediated by the positive-acting nit2 protein and by the negative-acting nmr protein. nit2, a globally acting factor, is a member of the gata family of regulatory proteins and has a single cys2/cys2 zinc finger dna-binding domain. the negative-acting nmr protein interacts via specific protein-protein binding with two dis ...19979427402
cloning and characterization of two phosphate transporters from medicago truncatula roots: regulation in response to phosphate and to colonization by arbuscular mycorrhizal (am) fungi.most vascular plants can acquire phosphate from the environment either directly, via the roots, or indirectly, via a fungal symbiont that invades the cortical cells of the root. here we have identified two cdna clones (mtpt1 and mtpt2) encoding phosphate transporters from a mycorrhizal root cdna library (medicago truncatula/glomus versiforme). the cdnas represent m. truncatula genes and the encoded proteins share identity with high-affinity phosphate transporters from arabidopsis, potato, yeast, ...19989425684
identification and characterization of a novel arabinoxylanase from wheat endogenous wheat (triticum aestivum) flour endoxylanase was purified to homogeneity from a crude wheat flour extract by ammonium sulfate precipitation and cation-exchange chromatography. the 30-kd protein had an isoelectric point of 9.3 or higher. a sequence of 19 amino acids at the nh2 terminus showed 84.2% identity with an internal sequence of 15-kd grain-softness protein, friabilin. high-performance anion-exchange chromatography and gel-permeation analysis of the hydrolysis products indica ...19979414565
mating types and sexual development in filamentous ascomycetes.the progress made in the molecular characterization of the mating types in several filamentous ascomycetes has allowed us to better understand their role in sexual development and has brought to light interesting biological problems. the mating types of neurospora crassa, podospora anserina, and cochliobolus heterostrophus consist of unrelated and unique sequences containing one or several genes with multiple functions, related to sexuality or not, such as vegetative incompatibility in n. crassa ...19979409146
purification and characterization of the catalytic subunit of protein phosphatase 1 from neurospora crassa.protein phosphorylation is a universal regulatory mechanism in eukaryotic cells. the phosphorylation state of proteins is affected by the antagonistic activities of protein kinases and phosphatases. protein phosphatases (pps) can be classified as serine/threonine and tyrosine specific phosphatases. ser/thr phosphatases are divided into four subclasses (pp1, pp2a, pp2b, pp2c) on the basis of their substrate specificity, metal ion dependence and inhibitor sensitivity. we were able to detect the ac ...19979406609
specific, high affinity binding sites for an antifungal plant defensin on neurospora crassa hyphae and microsomal membranes.hs-afp1, an antifungal plant defensin from seed of the plant heuchera sanguinea, was radioactively labeled using t-butoxycarbonyl-[35s]l-methionine n-hydroxysuccinimidyl ester, resulting in a 35s-labeled peptide with unaltered antifungal activity. [35s]hs-afp1 was used to assess binding on living hyphae of the fungus neurospora crassa. binding of [35s]hs-afp1 was found to be competitive, reversible, and saturable with an apparent kd of 29 nm and a bmax of 1.4 pmol/mg protein. [35s]hs-afp1 also b ...19979405418
arabidopsis nph1: a protein kinase with a putative redox-sensing domain.the nph1 (nonphototropic hypocotyl 1) gene encodes an essential component acting very early in the signal-transduction chain for phototropism. arabidopsis nph1 contains a serine-threonine kinase domain and lov1 and lov2 repeats that share similarity (36 to 56 percent) with halobacterium salinarium bat, azotobacter vinelandii nifl, neurospora crassa white collar-1, escherichia coli aer, and the eag family of potassium-channel proteins from drosophila and mammals. sequence similarity with a known ...19979405347
the production of gamma-linolenic acid by selected members of the dikaryomycota grown on different carbon this study, seven fungal strains, representing different phylogenetic groups within the dikaryomycota, were tested for the presence of gamma-linolenic acid [18:3(omega 6)], when grown in synthetic liquid media devoid of fatty acids, on a series of 40 different carbon sources. the fungal strains represented the species dipodascopsis uninucleata, eurotium rubrum, galactomyces geotrichum, neurospora crassa, saccharomyces cerevisiae, spongipellis unicolor and talaromyces flavus. cultures were per ...19979403104
white collar proteins: passing the light signal in neurospora crassa.the filamentous fungus neurospora crassa is an excellent paradigm for the study of blue light signal transduction. the isolation and characterization of the genes for two central regulators of the blue light response, white collar-1 and white collar-2, have begun to shed light on the mechanism of blue light signal transduction in fungi. these proteins are not only proposed to encode blue-light-activated transcription factors but also to be elements of the blue light signal transduction pathway.19979402704
genetic and molecular characterization of neurospora crassa mus-23: a gene involved in recombinational repair.a newly isolated mutant, mus-23, of neurospora crassa was found to be highly sensitive to a wide variety of mutagens, including uv light, methyl methanesulfonate, 4-nitroquinoline 1-oxide, n-methyl-n'-nitro-n-nitrosoguanidine and tert-butyl hydroperoxide. this mutant was originally isolated as a mutant that could not grow on medium containing histidine. meiosis and sporulation were defective in homozygous crosses between mus-23 haploids. the mus-23 gene is located on the right arm of lgii, betwe ...19979393441
g protein alpha subunit genes control growth, development, and pathogenicity of magnaporthe grisea.three g protein alpha subunit genes have been cloned and characterized from magnaporthe grisea: maga is very similar to cpg-2 of cryphonectria parasitica; magb is virtually identical to cpg-1 of cryphonectria parasitica, to gna1 of neurospora crassa, and to fada of emericella nidulans; and magc is most similar to gna2 of neurospora crassa. homologous recombination resulting in targeted deletion of maga had no effect on vegetative growth, conidiation, or appressorium formation. deletion of magc r ...19979390422
differential hsc70 expression during asexual development of neurospora crassa.the constitutive and the heat-shock-induced expression of members of heat-shock protein families changed during vegetative development and conidiation of neurospora crassa as determined by two-dimensional gel electrophoresis. western blot and elisa analyses revealed the highest amounts of the constitutive heat-shock protein 70 (hsc70) in conidiating aerial hyphae and dormant conidia. during conidial germination the amount of hsc70 decreased and subsequently increased during vegetative growth. st ...19979387240
characterization of the mitochondrial cytochrome b gene from venturia inaequalis.a new class of agricultural fungicides derived from the group of antifungal strobilurins acts as specific respiration inhibitors by binding to mitochondrial cytochrome b. the cytochrome b gene was cloned and sequenced from the mitochondrial genome of venturia inaequalis, the causal agent of apple scab. the gene was 10.65 kbp in size and contained seven exons and six introns. the exons encoded a protein of 393 amino acids. comparison of the deduced amino-acid sequence with cytochrome b proteins f ...19979371888
enzymatic properties and effect of ionic strength on periplasmic nitrate reductase (nap) from desulfovibrio desulfuricans atcc 27774.some sulfate reducing bacteria can induce nitrate reductase when grown on nitrate containing media being involved in dissimilatory reduction of nitrate, an important step of the nitrogen cycle. previously, it was reported the purification of the first soluble nitrate reductase from a sulfate-reducing bacteria desulfovibrio desulfuricans atcc 27774 (s.a. bursakov, m.-y. liu, w.j. payne, j. legall, i. moura, and j.j.g. moura (1995) anaerobe 1, 55-60). the present work provides further information ...19979367852
site and significance of cysteine residues in xylose reductase from neurospora crassa as deduced by fluorescence studies.inactivation of xylose reductase (xr) by p-hydroxy-mercury benzoate (phmb) was found to be biphasic with second-order rate constants of 80 and 6 m-1s-1 for the fast (kf) and slow (ks) phase respectively. spectroscopic studies indicated that the inactivation was due to modification of one cys residue per molecule of xr and not due to subsequent disruption of the quaternary structure. the binding of nadph to xr (kd 0.9 microm) was depressed on modification of the enzyme by phmb (kd 2.3 microm). th ...19979367847
primary structure of neurospora crassa gamma-tubulin.we report the isolation and characterization of a cdna-clone for gamma-tubulin from n. crassa. the deduced amino-acid sequence of the cdna-clone most resembles that of gamma-tubulins from other fungi. differential southern blot analysis demonstrates that most probably a single gene represents gamma-tubulin. in addition, northern blot analysis shows that most probably only one single mrna encoding gamma-tubulin is transcribed in n. crassa. in a phylogenetic tree that includes all known gamma-tubu ...19979358070
high-affinity no(3-)-h+ cotransport in the fungus neurospora: induction and control by ph and membrane voltage.high-affinity nitrate transport was examined in intact hyphae of neurospora crassa using electrophysiological recordings to characterize the response of the plasma membrane to no3- challenge and to quantify transport activity. the no3(-)-associated membrane current was determined using a three electrode voltage clamp to bring membrane voltage under experimental control and to compensate for current dissipation along the longitudinal cell axis. nitrate transport was evident in hyphae transferred ...19979351892
impairment of calcineurin function in neurospora crassa reveals its essential role in hyphal growth, morphology and maintenance of the apical ca2+ gradient.the function of neurospora crassa calcineurin was investigated in n. crassa strains transformed with a construct that provides for the inducible expression of antisense rna for the catalytic subunit of calcineurin (cna-1). induction of antisense rna expression was associated with reduced levels of cna-1 mrna and of immunodetectable cna1 protein and decreased calcineurin enzyme activity, indicating that a conditional reduction of the target function had been achieved in antisense transformants wi ...19979349701
mutations in genes encoding the mitochondrial outer membrane proteins tom70 and mdm10 of podospora anserina modify the spectrum of mitochondrial dna rearrangements associated with cellular death.tom70 and mdm10 are mitochondrial outer membrane proteins. tom70 is implicated in the import of proteins from the cytosol into the mitochondria in saccharomyces cerevisiae and neurospora crassa. mdm10 is involved in the morphology and distribution of mitochondria in s. cerevisiae. here we report on the characterization of the genes encoding these proteins in the filamentous fungus podospora anserina. the two genes were previously genetically identified through a systematic search for nuclear sup ...19979343397
molecular genetics of sulfur assimilation in filamentous fungi and yeast.the filamentous fungi aspergillus nidulans and neurospora crassa and the yeast saccharomyces cerevisiae each possess a global regulatory circuit that controls the expression of permeases and enzymes that function both in the acquisition of sulfur from the environment and in its assimilation. control of the structural genes that specify an array of enzymes that catalyze reactions of sulfur metabolism occurs at the transcriptional level and involves both positive-acting and negative-acting regulat ...19979343344
the neurospora crassa cya-5 nuclear gene encodes a protein with a region of homology to the saccharomyces cerevisiae pet309 protein and is required in a post-transcriptional step for the expression of the mitochondrially encoded coxi protein.the cya-5 nuclear mutant of neurosopora crassa was previously shown to be deficient in cytochrome aa3, cytochrome c oxidase activity, and the immunologically detectable coxi protein. we have now demonstrated that the mitochondria of this mutant contain mrna for the coxi protein and that coxi cannot be detected during pulse-chase labeling experiments of mitochondrial translation products. cloning and analysis of the cya-5 gene reveal a long open reading frame capable of encoding a 1136 amino-acid ...19979342407
evidence for a cysteine-histidine thioether bridge in functional units of molluscan haemocyanins and location of the disulfide bridges in functional units d and g of the betac-haemocyanin of helix functional units d and g from the betac-haemocyanin of the gastropod helix pomatia, aminoacid analysis in the presence of dimethyl sulfoxide showed the occurrence of seven cysteine residues. titration with 5,5'-dithiobis(2-nitrobenzoic acid), however, did not reveal any free thiol group. pepsinolysis at ph 2.0 followed by amino acid analysis and partial sequencing of the cysteine-containing peptides showed that six cysteine residues are involved in the formation of three disulfide bridges at ...19979342242
mating-type genes from the homothallic fungus sordaria macrospora are functionally expressed in a heterothallic ascomycete.homokaryons from the homothallic ascomycte sordaria macrospora are able to enter the sexual pathway and to form fertile fruiting bodies. to analyze the molecular basis of homothallism and to elucidate the role of mating-products during fruiting body development, we cloned and sequenced the entire s. macrospora mating-type locus. comparison of the sordaria mating-type locus with mating-type idiomorphs from the heterothallic ascomycetes neurospora crassa and podospora anserina revealed that sequen ...19979335594
fungal phosphate transporter serves as a receptor backbone for gibbon ape leukemia virus.pit1, the receptor for gibbon ape leukemia virus (galv), is proposed to be an integral membrane protein with five extracellular loops. chimeras made between pit1 homologs differing in permissivity for infection and between pit1 and the related protein pit2 have shown that the fourth extracellular loop plays a critical role in infection. however, further elucidation of the roles of the extracellular loops in infection is hampered by the high level of sequence similarity among these proteins. the ...19979311843
dna methylation inhibits elongation but not initiation of transcription in neurospora plants, animals, and fungi, dna methylation is frequently associated with gene silencing, yet little is known about the role of the methylation in silencing. in neurospora crassa, repeated sequences are silenced by repeat-induced point mutation (rip) and genes that have suffered numerous gc --> at mutations by rip are typically methylated at remaining cytosines. we investigated possible effects on transcription from methylation associated with rip by taking advantage of 5-azacytidine, which p ...19979308966
temperature compensation of the circadian period length--a special case among general homeostatic mechanisms of gene expression?in neurospora crassa, as well as in other organisms, the expression of housekeeping genes is transiently suppressed after exposure to higher temperatures (30-45 degrees c); expression is then reactivated and adapts after a few-hours to values closer to the initial rates. adaptive mechanisms apparently exist in the processes of transcription, rna processing, and translation and render protein synthesis rates temperature compensated. heat shock proteins (hsps) play an important role within these m ...19979298284
temperature compensation and membrane composition in neurospora crassa.the link between temperature compensation of the circadian rhythm and temperature-induced adjustment of membrane composition in neurospora crassa is briefly reviewed. in common with most organisms, neurospora responds to changes in growth temperature by adjusting its lipid composition, primarily by increasing the degree of unsaturation of its fatty acids at low temperature. this may result in maintenance of either membrane fluidity or phase transition behavior over a range of temperatures. in ne ...19979298281
the ornithine decarboxylase gene from candida albicans. sequence analysis and expression during dimorphism.the gene (caodc) coding for ornithine decarboxylase, a key enzyme in polyamine biosynthesis, was cloned from candida albicans by pcr and characterized. the deduced protein contains 470 amino acids together with the substrate- and co-factor-binding sequences which define the ornithine decarboxylases of eukaryotic species. it shows a high homology with other odcs, mainly those from saccharomyces cerevisiae and neurospora crassa. a putative pest sequence, which correlates quite well with those desc ...19979294258
isolation of quelling-defective (qde) mutants impaired in posttranscriptional transgene-induced gene silencing in neurospora crassa.we report the isolation of 15 neurospora crassa mutants defective in "quelling" or transgene-induced gene silencing. these quelling-defective mutants (qde) belonging to three complementation groups have provided insights into the mechanism of posttranscriptional gene silencing in n. crassa. the recessive nature of the qde mutations indicates that the encoded gene products act in trans. we show that when qde genes are mutated in a transgenic-induced silenced strain containing many copies of the t ...19979294193
expression of a plant protein by neurospora crassa.heterologous expression of plant genes may serve as an important alternative for producing plant proteins. we have investigated the ability of the fungus neurospora crassa to secrete zeamatin, a protein produced by zea mays. zeamatin was induced after being fused to glucoamylase, an extracellular hydrolase produced by n. crassa. glucoamylase induction and other culture parameters were monitored in untransformed n. crassa grown in shaken liquid culture. a dna plasmid, pgez, was constructed by ins ...19979292999
contact-sensing by hyphae of dermatophytic and saprophytic or thigmotropism is the directional growth response of cells in relation to topographical guidance cues. thigmotropism is thought to play a major role in the location of infectable sites on plants by phytopathogenic fungi and has recently been shown to be a property of hyphae in the human pathogenic fungus candida albicans. here we show that hyphae of the dermatophytes epidermophyton floccosum, microsporum canis and trichophyton mentagrophytes reorientate their direction of growt ...19979292428
expressed sequences from conidial, mycelial, and sexual stages of neurospora the neurospora genome project at the university of new mexico, expressed sequence tags (ests) corresponding to three stages of the life cycle of the filamentous fungus neurospora crassa are being analyzed. the results of a pilot project to identify expressed genes and determine their patterns of expression are presented. 1,865 partial complementary dna (cdna) sequences for 1,409 clones were determined using single-pass sequencing. contig analysis allowed the identification of 838 unique ests ...19979290248
genome analysis on linkage group vi of neurospora crassa.two chromosome walks covering 420 and 110 kb on the left arm of linkage group vi (lgvil) of neurospora crassa were purscrooued with the goal of cloning carotenogenic loci. complementation analysis with clones isolated in the 420-kb walk allowed identification of the yellow-1 (ylo-1) gene which is essential for neurospora carotenogenesis. we have physically located a second gene, unknown-13 (un-13), between the cross-pathway control-1, (cpc-1) and ylo-1 loci. cloning of a second potential caroten ...19979290246
genome analysis in neurospora crassa; cloning of four loci arginine-1 (arg-1), methionine-6 (met-6), unknown-7 (un-7), and ribosome production-1 (rip-1) and associated chromosome walking.we have cloned four neurospora crassa genes by complementation analysis. cloned genes include the arginine-1 (arg-1), methionine-6 (met-6), unknown-7 (un-7), and ribosome production-1 (rip-1) loci. chromosome walks were initiated in ordered cosmid libraries from the cloned loci. a total of about 700 kb of the neurospora genome is covered in these walks.19979290245
mapping chromosome landmarks in the centromere i region of neurospora crassa.chromosome translocation breakpoints, rflp heterozygosity in partial chromosome duplications, and rflp-marked crossover events have been used as chromosomal landmarks to find the position and orientation of cloned regions flanking centromere i of neurospora crassa. determination of physical:genetic ratios in genomic regions flanking the loci mei-3, un-2, and his-2 supports previous evidence indicating that recombinational activity is lower in regions flanking centromere i than in the general n. ...19979290244
cloning heterologous genes: problems and approaches.model fungi such as neurospora crassa, aspergillus niger, and saccharomyces cerevisiae have provided a wealth of genetic information and are currently the object of cooperative genome sequencing projects. many agriculturally and medically economic important pathogenic fungi, however, are less well characterized, which makes it difficult to study their genes and gene products. gene sequences from model fungi offer a unique opportunity to clone cognate genes from pathogenic counterparts. in this r ...19979290241
the genome and genes of neurospora crassa.neurospora crassa is an organism with a 7-decade contribution to genetic research. in a genome of 42.9 mb and just over 1000 map units, to date over 800 different genes have been identified by phenotype and/or map location, and 222 genes have been characterized by sequencing. methods by which analysis of the genome has been carried out are discussed, including linkage, rflp, and chromosome walking. characterized centomeres, telomeres, the nucleolar organizer and the dispersed 5s rrna genes are d ...19979290240
reversal in the direction of movement of a molecular motor.kinesin and non-claret disjunctional (ncd) are molecular motors of the kinesin superfamily that move in opposite directions along microtubules. the molecular basis underlying the direction of movement is unclear, although it is thought to be an intrinsic property of the motor domain, a conserved region about 330 amino acids in length. the motor domain is found at the amino terminus in conventional kinesins, but at the carboxy terminus in ncd. here we report on a chimaera composed of the motor do ...19979288974
overlapping functions for two g protein alpha subunits in neurospora crassa.heterotrimeric g proteins, consisting of alpha, beta and gamma subunits, mediate a variety of signaling pathways in eukaryotes. we have previously identified two genes, gna-1 and gna-2, that encode g protein alpha subunits in the filamentous fungus neurospora crassa. mutation of gna-1 results in female infertility and sensitivity to hyperosmotic media. in this study, we investigate the expression and functions of gna-2. results from western analysis and measurements of gna-2 promoter-lacz fusion ...19979286674
genetic regulation of the qa gene cluster of neurospora crassa: induction of qa messenger ribonucleic acid and dependency on qa-1 in vitro protein-synthesizing system (rabbit reticulocyte) was programmed with total polyadenylated messenger ribonucleic acid from wild type and various mutants in the qa gene cluster of neurospora crassa. the products of two of the qa genes, quinate dehydrogenase (qa-3+) and dehydroshikimate dehydratase (qa-4+), were identified by specific immunoprecipitation and sodium dodecyl sulfate-slab gel electrophoresis. the results indicated that for both genes induction of a specific enzyme activit ...19819279395
purification of vacuoles from neurospora crassa.the neurospora crassa vacuole, defined by its content of basic amino acids, polyphosphate, protease, phosphatases, and alpha-mannosidase, was purified to near homogeneity. the procedure depends upon homogenization of snail gut enzyme-digested cells in a buffer osmotically stabilized with 1 m sorbitol, differential centrifugation of the extract, and sucrose density gradient centrifugation of the organellar pellet. isopycnic centrifugation of vacuoles in 2.25 m sorbitol-metrizamide density gradien ...19819279392
ribosome stalling is responsible for arginine-specific translational attenuation in neurospora crassa.the neurospora crassa arg-2 upstream open reading frame (uorf) plays a role in negative arginine-specific translational regulation. primer extension inhibition analyses of arg-2 uorf-containing rna translated in a cell-free system in which arginine-specific regulation was retained revealed "toeprints" corresponding to ribosomes positioned at the uorf initiation and termination codons and at the downstream initiation codon. at high arginine concentrations, the toeprint signal corresponding to rib ...19979271370
isolation and characterization of the krev-1 gene, a novel member of ras superfamily in neurospora crassa: involvement in sexual cycle progression.genes belonging to the ras superfamily encode low-molecular-weight gtp/gdp-binding proteins that are highly conserved in wide variety of organisms. we used the polymerase chain reaction (pcr) to isolate a novel member of the ras superfamily from the filamentous fungus neurospora crassa and obtained a mammalian krev-1 homolog. we named the gene krev-1 and analyzed its structure and function. the krev-1 gene encodes a polypeptide of 225 amino acids, which is nearly 60% homologous to the mammalian ...19979267439
allelic specificity at the het-c heterokaryon incompatibility locus of neurospora crassa is determined by a highly variable filamentous fungi, the ability to form a productive heterokaryon with a genetically dissimilar individual is controlled by specific loci termed het loci. only strains homozygous for all het loci can establish a heterokaryon. in neurospora crassa, 11 loci, including the mating-type locus, regulate the capacity to form heterokaryons. an allele of the het-c locus (het-cor) of n. crassa has been previously characterized and encodes a nonessential 966 amino acid glycine-rich protein. herein, we de ...19979258675
isolation and characterisation of a novel stress-inducible pdi-family gene from aspergillus niger.current strategies to improve the secretion of heterologous proteins in aspergillus niger include the manipulation of chaperones and foldases specific to the endoplasmic reticulum (er). a family of er-specific proteins which share active-site homology wit protein disulfide isomerase (pdi) has been identified from other systems, many of which are inducible by agents which cause malfolding of proteins in the er. here we report identification of tiga from aspergillus niger and erp38 from neurospora ...19979256071
ppt-1, a neurospora crassa ppt/pp5 subfamily serine/threonine protein phosphatase.we isolated a n. crassa cdna clone encoding a novel-type serine/threonine phosphatase. the gene (mapped to lgvr), designated ppt-1, encodes a 479 amino acid putative polypeptide which contains a conserved tetratricopeptide repeat (tpr) motif. ppt-1 transcript levels are abundant in conidia and decrease during germination, indicating that ppt-1 is developmentally regulated.19979256060
heat shock protein 80 of neurospora crassa, a cytosolic molecular chaperone of the eukaryotic stress 90 family, interacts directly with heat shock protein 70.the subunit structure of hsp80, the most abundant heat-shock protein of neurospora crassa, was examined by chemical cross-linking of the purified protein in vitro. resolution of glutaraldehyde-treated hsp80 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis sds-page suggests that the native state of this protein is a tetramer; the relative proportion of cross-linked species, estimated by the fraction of protein recovered in each category, is consistent with a dimer-of-dimer structure. ...19979254620
monoclonal antibodies as probes for fungal wall structure during morphogenesis.three monoclonal antibodies (mabs), s4d1, s3b3 and s1e5, were produced from hybridoma cell lines raised from mice immunized with hyphal walls of neurospora crassa and one (pax-1) from mice immunized with hyphal walls of paxillus involutus. in immunofluorescence studies, the three n. crassa mabs recognized epitopes with different patterns of distribution at the hyphal surface of n. crassa. s4d1 recognized an epitope which was present on the surface of both conidia and hyphae; s3b3 recognized an e ...19979245814
gene targeting is locus dependent in the filamentous fungus aspergillus nidulans.the effect of altering the conditions of transformation on the efficiency of gene targeting in filamentous fungi was studied using aspergillus nidulans as a model organism. the niad and amds genes of a. nidulans, which are both involved in nitrogen source utilisation, were selected as target loci. homologous recombination of transforming dna at these loci resulted in niad and amds mutants with an impaired ability to utilise nitrate or acetamide as the sole nitrogen source, respectively. vectors ...19979236780
the geranylgeranyl diphosphate synthase gene of gibberella fujikuroi: isolation and expression.the rice pathogen, gibberella fujikuroi, produces large amounts of gibberellins, a group of natural plant hormones, which induce the superelongation (bakanae) disease of rice. gibberellins are diterpenoid compounds which are synthesized via the isoprenoid pathway. here we report the isolation and molecular characterization of the geranylgeranyl diphosphate synthase (ggs) gene from g. fujikuroi. geranylgeranyl diphosphate synthase is a key enzyme in isoprenoid biosynthesis. southern blot analysis ...19979230902
footprinting of the spinach nitrite reductase gene promoter reveals the preservation of nitrate regulatory elements between fungi and higher plants.nitrite reductase (nir) is the second enzyme in the nitrate assimilatory pathway reducing nitrite to ammonium. the expression of the nir gene is induced upon the addition of nitrate. in an earlier study, a 130 bp upstream region of the spinach nir gene promoter, located between -330 to - 200, was shown to be necessary for nitrate induction of beta-glucuronidase (gus) expression in tissue-specific manner in transgenic tobacco plant [28]. to further delineate the cis-acting elements involved in ni ...19979225857
identification of a motor protein required for filamentous growth in ustilago maydis.the phytopathogenic fungus ustilago maydis exists in two stages, the yeast-like haploid form and the filamentous dikaryon. both pathogenicity and dimorphism are genetically controlled by two mating-type loci, with only the filamentous stage being pathogenic on corn. we have identified two genes (kin1 and kin2) encoding motor proteins of the kinesin family. kin1 is most similar to the human cenp-e gene product, while kin2 is most closely related to the conventional kinesin nkin of neurospora cras ...19979218789
kinesin is essential for cell morphogenesis and polarized secretion in neurospora crassa.kinesin is a force-generating molecule that is thought to translocate organelles along microtubules, but its precise cellular function is still unclear. to determine the role of kinesin in vivo, we have generated a kinesin-deficient strain in the simple cell system neurospora crassa. null cells exhibit severe alterations in cell morphogenesis, notably hyphal extension, morphology and branching. surprisingly, the movement of organelles visualized by video microscopy is hardly affected, but apical ...19979214620
conformation and microenvironment of the active site of xylose reductase inferred by fluorescent chemoaffinity labeling.conformation and microenvironment at the active site of xylose reductase (xr) from neurospora crassa was probed with fluorescent chemoaffinity labeling (fcal) using o-phthalaldehyde as a chemical initiator. formation of a single isoindole derivative resulted in complete inactivation of the enzyme as judged by spectroscopic and fluorescence studies. kinetic analysis of the 2,4,6-trinitrobenzenesulfonic-acid-modified xr implicated the presence of an essential lysine residue at the active site of x ...19979208923
a kinesin-like mechanoenzyme from the zygomycete syncephalastrum racemosum shares biochemical similarities with conventional kinesin from neurospora crassa.the kinesin superfamily consists of mechanoenzymes that convert chemical energy, stored in nucleoside triphosphates, into movement along microtubules. the founding member of this protein superfamily, the so-called conventional kinesin, was only known from animal sources until the recent description of kinesin from the filamentous fungus neurospora crassa (g. steinberg, m. schliwa, mol. biol. cell 6, 1605-1618 (1995)). to determine whether similar motors with comparable features are common in oth ...19979208225
isolation of developmentally regulated genes from the edible mushroom agaricus bisporus.from a cdna library, constructed from mushroom primordia, nine cdnas were isolated which were either induced or specifically expressed during fruit body development and maturation of the basidiomycete agaricus bisporus. these cdnas varied in size from 372 to 1019 bp and hybridized to transcripts of 400-1600 nt. four of the cdnas were only expressed in the generative phase of the life cycle while the other five cdnas were strongly induced but had low steady-state mrna levels in vegetatively grown ...19979202475
adaptation of proteases and carbohydrates of saprophytic, phytopathogenic and entomopathogenic fungi to the requirements of their ecological niches.the abilities of isolates of saprophytes (neurospora crassa, aspergillus nidulans), an opportunistic human pathogen (aspergillus fumigatus), an opportunistic insect pathogen (aspergillus flavus), plant pathogens (verticillium albo-atrum, verticillium dahliae, nectria haematococca), a mushroom pathogen (verticillium fungicola) and entomopathogens (verticillium lecanii, beauveria bassiana, metarhizium anisopliae) to utilize plant cell walls and insect cuticle components in different nutrient media ...19979202474
a neurospora crassa mutant altered in the regulation of l-amino acid oxidase.the isolation and characterization of a neurospora crassa mutant altered in l-amino oxidase regulation is reported. the previously isolated gln-1br8 strain, which only synthesizes the glutamine synthetase alpha monomer and lacks the beta monomer, was used as parental strain. a mutant derivative of strain was selected for its ability to grow on minimal medium in the presence of dl-methionine-sr-sulfoximine (mso), an inhibitor of glutamine synthetase activity. this gln-1br8;msor mutant overcame th ...19979202472
hydrophobic properties of nad glycohydrolase from neurospora crassa conidia and interaction with dioxane.nad glycohydrolase (nadase, ec from neurospora crassa conidia shows marked hydrophobic properties which are related to the self inhibition of the enzyme. both aliphatic amines and carboxylic acids are able to inhibit noncompetitively the catalytic activity of the enzyme and the inhibition depends on the non-polar moiety of the substances. also dioxane is an inhibitor of nad glycohydrolase even though it apparently increases the specific activity of the enzyme. this effect can be explain ...19979193681
pronounced cytoplasmic ph gradients are not required for tip growth in plant and fungal cells.the existence of pronounced cytoplasmic ph gradients within the apices of tip-growing cells, and the role of cytoplasmic ph in regulating tip growth, were investigated in three different cell types: vegetative hyphae of neurospora crassa; pollen tubes of agapanthus umbellatus; and rhizoids of dryopteris affinis gametophytes. examination of cytoplasmic ph in growing cells was performed by simultaneous, dual emission confocal ratio imaging of the ph-sensitive probe carboxy snarf-1. considerable at ...19979191043
histidine kinases in signal transduction pathways of eukaryotes.autophosphorylating histidine kinases are an ancient conserved family of enzymes that are found in eubacteria, archaebacteria and eukaryotes. they are activated by a wide range of extracellular signals and transfer phosphate moieties to aspartates found in response regulators. recent studies have shown that such two-component signal transduction pathways mediate osmoregulation in saccharomyces cerevisiae, dictyostelium discoideum and neurospora crassa. moreover, they play pivotal roles in respon ...19979191038
a ras homologue of neurospora crassa regulates order to study the role of signal transduction pathways in the regulation of morphology in neurospora crassa, we cloned and characterized a ras homologue, termed nc-ras2. the predicted protein product of this gene is composed of 229 amino acid residues and contains all the consensus sequences shared by the ras protein family. the gene is located in linkage group v. an nc-ras2 disruptant showed morphological characteristics very similar to those of the smco7 mutant, which also maps to linkage ...19979180696
a putative rhamnogalacturonase required for sexual development of neurospora previous work, the asd-i (ascus development) gene of the filamentous fingus neurospora crassa was identified as a gene expressed preferentially during the sexual cycle and shown to be essential for normal sexual development. the asd-i gene has been sequenced and further characterized. it contains two introns, the first of which is in-frame and inefficiently or differentially spliced. the predicted asd-i protein has extensive homology with rhamnogalacturonase b of aspergillus aculeatus, which ...19979178004
isolation and characterization of a temperature-sensitive circadian clock mutant of neurospora crassa.a new circadian clock mutant has been isolated in neurospora crassa. this new mutation, called period-6 (prd-6), has two features novel to known clock mutations. first, the mutation is temperature sensitive. at restrictive temperatures (above 21 degrees) the mutation shortens circadian period length from a wild-type value of 21.5 hr to 18 hr. at permissive temperatures (below 21 degrees) the mutant has a 20.5-hr period length close to that of the wild-type strain. second, the prd-6 mutation is e ...19979178003
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