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gtp is required for the integration of a fragment of the neurospora crassa h(+)-atpase into homologous microsomal vesicles.the integration of a fragment of the neurospora crassa plasma membrane h(+)-atpase was examined to determine if insertion of the fragment into homologous microsomal vesicles is obligatorily dependent on a nucleoside triphosphate. rna transcripts that encoded the amino terminal 344 amino acids of the neurospora crassa plasma membrane h(+)-atpase(pma(344)+) were translated in a n. crassa in vitro system. the pma(344)+ integrated post-translationally into homologous microsomal vesicles independent ...19911711898
the cdna sequence and expression of an ubiquitin-tail gene fusion in neurospora crassa.the genome of neurospora crassa contains at least one natural fusion gene encoding a single ubiquitin (ubi) unit with a 78-amino acid c-terminal extension. the predominantly basic tail sequence corresponds to a highly conserved ribosomal protein identified in other organisms. the 0.7-kb ubi fusion transcript is mainly expressed in germinating conidia and other stages of active cell replication. under starvation conditions attained by nutrient depletion, or after polyamine depletion, the ubi fusi ...19911650731
nit-3, the structural gene of nitrate reductase in neurospora crassa: nucleotide sequence and regulation of mrna synthesis and turnover.the nit-3 gene of the filamentous fungus neurospora crassa encodes the enzyme nitrate reductase, which catalyzes the first reductive step in the highly regulated nitrate assimilatory pathway. the nucleotide sequence of nit-3 was determined and translates to a protein of 982 amino acid residues with a molecular weight of approximately 108 kda. comparison of the deduced nit-3 protein sequence with the nitrate reductase protein sequences of other fungi and higher plants revealed that a significant ...19911829499
effects of heat shock on the level of trehalose and glycogen, and on the induction of thermotolerance in neurospora crassa.neurospora crassa conidiospore germlings exposed to a heat shock (30-45 c) rapidly accumulated trehalose and degraded glycogen, even in the presence of cycloheximide. this phenomenon was also rapidly reversible upon return of the cells at 30 degrees c. trehalose accumulation at 45 degrees c demanded an exogenous source of carbon and either glucose or glycerol fulfilled such requirement. experiments with the cyclic amp-deficient cr-1 mutant suggested that the effects of temperature shifts on treh ...19911645296
isolation of uridine auxotrophs from trichoderma reesei and efficient transformation with the cloned ura3 and ura5 genes.uridine auxotrophs of the filamentous fungus trichoderma reesei have been selected using a positive screening procedure with 5-fluoro orotate. mutants deficient for the orotidine-5'-phosphate decarboxylase gene (ura3 mutants) and for the orotate phosphoribosyl transferase gene (ura5 mutants) have been characterized. the homologous ura3 and ura5 genes have been isolated and used to transform the auxotrophic mutants. transformation efficiency with these homologous systems is very high (greater tha ...19911913875
regulation of laccase synthesis in induced neurospora crassa cultures.rapidly growing cultures of n. crassa do not produce laccase. exposure of this fungus to different inducing agents leads to a de novo biosynthesis of extracellular laccase in vegetative cultures. in this study the induction of laccase after addition of cycloheximide and d-phenylalanine is reported. de novo synthesis of laccase mrna was followed over 96 h after induction. a fast appearance of the message, as well as its presence over a rather long period, indicates a regulation on a transcription ...19911833078
determination of electric parameters of cell membranes by a dielectrophoresis method.marszalek, p., j. j. zielinsky, and m. fikus (1989. bioelectrochem. bioenerg. 22:289-298) have described a novel design for measuring the complete dielectrophoretic spectrum of a single cell. from the analysis of the dielectrophoretic spectrum, the membrane conductivity, sigma membr, and the membrane dielectric permittivity, epsilon membr, of the cell may be determined according to the theory of dielectrophoresis described by sauer, f. a. (1985. interactions between electromagnetic field and cel ...19911831052
photostimulation of conidiation in mutants of neurospora crassa.various mutants of neurospora crassa were screened for light-stimulated conidiation which is a blue light effect and, at least in strain albino-band, is mediated by the flavoprotein nitrate reductase (nr). nr- mutants showed practically no photoconidiation under standard conditions. however, in fusion products of nit-1 (diaphorase activity present, terminal activity missing) plus nit-3 (terminal activity present, diaphorase activity missing), nr activities and photoconidiation were partially res ...19911830899
loss of nad(p)-reducing power and glutathione disulfide excretion at the start of induction of aerial growth in neurospora crassa.when exponentially growing hyphae of neurospora crassa in aerated liquid cultures are filtered and the resulting mycelial mat is exposed to air, aerial hyphae develop and synchronous conidiation is obtained. the hyphae in direct contact with air adhere to each other within minutes and form aerial hyphae during the following 12 h; the hyphae which are not in direct contact with air do not adhere to each other and do not form aerial hyphae. previous data indicated that oxidative stress was generat ...19911827113
an inducible gene expression system for neurospora crassa.neurospora crassa acetyl coa synthetase is highly induced when the growing mycelium is transferred from sucrose- to acetate-based medium. the inducible promoter of this gene has been isolated and used to control the expression of glutamate dehydrogenase. transformants containing this expression cassette show gdh levels up to 25 times higher than the nontransformed host strain. this expression cassette will form the basis of a system of heterologous gene expression.19911369451
regulation of biosynthesis of l-amino acid oxidase by neurospora crassa.l-amino acid oxidase was purified from liquid cultures of neurospora crassa induced by l-phenylalanine, d-phenylalanine, atp and cycloheximide. although the four enzyme species isolated were found to differ in size and electrophoretic mobility, they were the product of a single gene as demonstrated by genomic southern analysis. northern analysis of total cellular rna showed a rapid increase of l-amino acid oxidase mrna in response to the different inducing agents studied. these data suggest that ...19911829425
metalloselenonein, the selenium analogue of metallothionein: synthesis and characterization of its complex with copper ions.we used an automated peptide synthesizer to produce a peptide, metalloselenonein, that contains selenocysteine residues substituted for all cysteine residues in neurospora crassa copper metallothionein. metalloselenonein binds 3 mol of cu(i) per mol. this adduct shows a broad absorption band between 230 and 400 nm and a fluorescence band at 395 nm, which can be attributed to copper-selenolate coordination. the circular dichroism spectrum of the copper-metalloselenonein complex shows a positive b ...19911826562
ca2+ calmodulin-dependent protein kinase activity in the ascomycetes neurospora crassa.deae-cellulose column chromatography of neurospora crassa soluble mycelial extracts leads to the resolution of three major protein kinase activity peaks designated pki, pkii, and pkiii. pkii activity is stimulated by ca2+ and neurospora or brain calmodulin. maximal stimulation was observed at 2 microm-free ca2+ and 1 microgram/ml of the modulator. the stimulatory effect of the ca(2+)-calmodulin complex was blocked by egta and by some calmodulin antagonists such as phenothiazine drugs or compound ...19911652680
regulation of molybdenum cofactor species in the green alga chlamydomonas reinhardtii.molybdenum cofactor (moco) of molybdoenzymes is constitutively produced in cells of the green alga chlamydomonas reinhardtii grown in ammonium media, under which conditions certain molybdoenzymes are not synthesized. in soluble form, moco was found to be present in several forms: (i) as a low mr free species; (ii) bound to a moco-carrier protein of about 50 kda that could release moco to directly reconstitute in vitro nitrate reductase activity in the nit-1 mutant of neurospora crassa, but not t ...19911826614
nucleotide and dna uptake by neurospora crassa: involvement of an uptake stimulating protein.the basal and dusf (dna-uptake-stimulating factor, described previously by schablik and szabó (1981) fems microbiol. lett. 10, 395-397) stimulated uptake of [3h]dna and radioactive nucleotides by neurospora crassa (fgsc 1118, slime) cell-wall-less strain was studied. the uptake of [3h]dna by the cells is a saturable and time-dependent process. the ph and temperature optimum for [3h]dna uptake are ph 7 and 27 degrees c, respectively. both basal and dusf-stimulated uptake of [3h]dna are inhibited ...19911826455
specificity of repeat-induced point mutation (rip) in neurospora: sensitivity of non-neurospora sequences, a natural diverged tandem duplication, and unique dna adjacent to a duplicated region.the process designated rip (repeat-induced point mutation) alters duplicated dna sequences in the sexual cycle of neurospora crassa. we tested whether non-neurospora sequences are susceptible to rip, explored the basis for the observed immunity to this process of a diverged tandem duplication that probably arose by a natural duplication followed by rip (the neurospora zeta-eta region), and investigated whether rip extends at all into unique sequences bordering a duplicated region. bacterial sequ ...19911827630
recurrence of repeat-induced point mutation (rip) in neurospora crassa.duplicate dna sequences in the genome of neurospora crassa can be detected and mutated in the sexual phase of the life cycle by a process termed rip (repeat-induced point mutation). rip occurs in the haploid nuclei of fertilized, premeiotic cells before fusion of the parental nuclei. both copies of duplications of gene-sized sequences are affected in the first generation at frequencies of approximately 50-100%. we investigated the extent to which sequences altered by rip remain susceptible to th ...19911827629
surface topography and molecular stoichiometry of the mitochondrial channel, vdac, in crystalline arrays.the mitochondrial outer membrane contains a protein, called vdac, that forms large aqueous pores. in neurospora crassa outer membranes, vdac forms two-dimensional crystalline arrays whose size and frequency can be greatly augmented by lipase treatment of these membranes (c. mannella, science 224, 165, 1984). fourier filtration and surface reconstruction of freeze-dried/shadowed (45 degrees) arrays produced detailed images of two populations of crystals, whose lattices are mirror images of each o ...19911725124
purification and characterization of glutamate decarboxylase from neurospora crassa conidia.l-glutamate decarboxylase, an enzyme under the control of the asexual developmental cycle of neurospora crassa, was purified to homogeneity from conidia. the purification procedure included ammonium sulfate fractionation and deae-sephadex and cellulose phosphate column chromatography. the final preparation gave a single band on sodium dodecyl sulfate-polyacrylamide gels with a molecular weight of 33,200 +/- 200. a single band coincident with enzyme activity was found on native 7.5% polyacrylamid ...19911825829
kinetic properties of de-repressible alkaline phosphatase (ec 3.1.3.1) from neurospora crassa.de-repressible alkaline phosphatase from n. crassa shows inhibition by pnp-p and a hyperbolic mixed-type inhibition by pi. both increasing concentrations of pi and decreases in assay ph abolished inhibition by the substrate. also, pi promoted polymerization of the enzyme molecule, whose effect may account for the inhibitory behaviour shown by the enzyme in the presence of low pi concentrations.199124424939
polyamine toxicity in neurospora crassa: protective role of the vacuole.we used mutant strains of neurospora crassa to define the discretionary capacity of this species for excess putrescine. the spe-3 mutant, which accumulates putrescine internally, and the puu-1 mutant, which accumulates toxic levels of putrescine from the medium, both sequestered large excesses of putrescine in vacuoles. concomitantly in puu-1, inorganic polyphosphate increased modestly and some of the monovalent cation of the vacuole was discharged. these two factors contribute to the increased ...19911832828
a new senescence-inducing mitochondrial linear plasmid in field-isolated neurospora crassa strains from india.several field-collected strains of neurospora crassa from the vicinity or aarey, bombay, india, are prone to precocious senescence and death. analysis of one strain, aarely-1e, demonstrated that the genetic determinants for the predisposition to senescence are maternally inherited. the senescence-prone strains contain a 7-kb, linear, mitochondrial dna plasmid, maranhar, which is not present in long-lived isolates from the same geographical location. the maranhar plasmid has inverted terminal rep ...19911648454
regulation of the proton/electron stoichiometry of mitochondrial ubiquinol:cytochrome c reductase by the membrane potential.the electron transfer reaction catalysed by mitochondrial ubiquinol:cytochrome c reductase is linked to the outwards translocation of protons with an h+ e- stoichiometry of 1 under non-membrane potential condition. the effect of the electrical membrane potential on the h+/e- stoichiometry was investigated. the enzyme was isolated from neurospora crassa, reconstituted into phospholipid vesicles and electrical membrane potentials of various values were generated across the membranes by means of th ...19911847681
induction and intracellular localization of the 80-kilodalton heat-shock protein of neurospora crassa.the most abundant heat-shock protein of neurospora crassa is a multimeric glycoprotein of 80-kilodaltons (i.e., hsp80), induced strongly by hyperthermia and at a lower level by sodium arsenite, ethanol, and carbon source depletion. immunoelectron microscopy, using indirect immunogold labelling demonstrated that hsp80 was undetectable in mycelium cultured at the normal growth temperature of 28 degrees c, but it appeared rapidly following the commencement of heat-shock treatment at 48 degrees c. h ...19921299272
nucleolar dense granules in cytochalasin-treated conidia of neurospora crassa. 19921288898
accumulation of the pre-assembled membrane arm of nadh:ubiquinone oxidoreductase in mitochondria of manganese-limited grown neurospora crassa.the nadh:ubiquinone oxidoreductase (complex i) of mitochondria is constructed from two arms arranged perpendicular to each other. the peripheral arm protruding into the matrix contains the proximal section of the electron pathway, and the membrane arm with all mitochondrially encoded subunits contains the distal section of the electron pathway. when neurospora crassa is grown under manganese limitation the formation of the peripheral arm is disturbed, but the membrane arm containing the iron-sul ...19921330699
vacuolar atpase of neurospora crassa: electron microscopy, gene characterization and gene inactivation/mutation.we are using three approaches to investigate the vacuolar atpase, v-atpase, from neurospora crassa. (1) examination in the electron microscope shows the enzyme has a 'ball and stalk' structure like the f-type atpases. however, the vacuolar atpase is significantly larger, has a prominent cleft in the head sector, and has extra components associated with the stalk and membrane sectors. (2) genes encoding three of the major subunits of the vacuolar atpase and the homologous subunits of the mitochon ...19921491233
length heterogeneity in its 2 and the methylation status of ccgg and gcgc sites in the rrna genes of the genus peronosclerospora.the polymerase chain reaction (pcr) was used with primers complementary to conserved flanking sequences to amplify the internal transcribed spacer 2 (its 2) of the rdna repeat units of five peronoscleropora isolates, one each of p. sorghi, p. maydis, p. sacchari and two of p. zeae. in contrast to the situation found in most-fungi that have been examined, length heterogeneity was evident in each sample. the rdna composition of the amplified bands was confirmed by southern hybridizations using an ...19921423729
genetic organization and structural features of maranhar, a senescence-inducing linear mitochondrial plasmid of neurospora crassa.the nucleotide sequence of maranhar, a senescence-inducing linear mitochondrial plasmid of neurospora crassa, was determined. the termini of the 7-kb plasmid are 349-bp inverted repeats (tirs). each dna strand contains a long open reading frame (orf) which begins within the tir and extends toward the centre of the plasmid. orf-1 codes for a single-subunit rna polymerase that is not closely related to that encoded by another neurospora plasmid, kalilo. the orf-2 product may be a b-type dna polyme ...19921423726
truffle melanogenesis: correlation with reproductive differentiation and ascocarp ripening.the present work uses histochemical techniques to investigate the correlation between reproductive differentiation and age of truffles (tuber aestivum and tuber melanosporum) with melanin synthesis. the dopa oxidase and tyrosine hydroxylase activities of tyrosinase have been localized within the ascocarp and melanin localization was performed by the schmorl's reaction. a true tyrosinase is present in truffles, able to oxidize both l-tyrosine and l-dopa. the tyrosinase activity is on in the young ...19921363133
characterization of assembly intermediates of nadh:ubiquinone oxidoreductase (complex i) accumulated in neurospora mitochondria by gene disruption.nadh:ubiquinone oxidoreductase, the respiratory chain complex i of mitochondria, is an assembly of some 25 nuclear-encoded and 7 mitochondrially encoded subunits. the complex has an overall l-shaped structure formed by a peripheral arm and an elongated membrane arm. the peripheral arm containing one fmn and at least three iron-sulphur clusters constitutes the nadh dehydrogenase segment of the electron pathway. the membrane arm with at least one iron-sulphur cluster constitutes the ubiquinone red ...19921433284
structure of the vacuolar atpase from neurospora crassa as determined by electron microscopy.we have examined the structure of the vacuolar atpase of neurospora crassa using negatively stained preparations of vacuolar membranes and of detergent-solubilized and gradient-purified atpase complexes. we also examined the peripheral sector (v1) of the enzyme after it had been removed and purified. using different stains, vacuolar membranes displayed ball-and-stalk structures similar to those of the intact mitochondrial atpase. however, the vacuolar atpase was clearly different from the mitoch ...19921388158
sexual development genes of neurospora crassa.the filamentous fungus neurospora crassa undergoes a complex program of sexual development to form a fruiting body composed of several kinds of specialized tissue. subtractive hybridization was used to isolate genes that are expressed preferentially during this sexual phase. many such sexual development (sdv) genes were identified in a cosmid library of neurospora genomic dna. fourteen of the sdv genes were subcloned, and their expression in mutant strains and under crossing and vegetative growt ...19921356883
cytology of recessive sexual-phase mutants from wild strains of neurospora crassa.wild-collected strains of neurospora crassa harbor recessive mutations that are expressed in the sexual phase when homozygous. thirty-two representative mutants that produced barren perithecia were examined cytologically. six of these mutants failed to form asci. of the remaining 26, chromosome pairing was disturbed in 12 and meiosis was disturbed at pachytene or diplotene in 5. seven mutants showed normal meiosis i but then diverged from the normal sequence, and two showed perithecial beak abno ...19921427061
photoinduction of albino-3 gene expression in neurospora crassa conidia.the synthesis of carotenoids is induced by blue light in neurospora crassa mycelia, while in conidia (the vegetative spores) the accumulation of carotenoids also occurs in the dark. the expression of the albino-3 (al-3) gene (coding for the carotenogenic enzyme geranyl-geranyl pyrophosphate synthetase) in isolated conidia was analysed. the level of al-3 mrna was shown to be increased in light-induced wild type (wt) conidia. this light response was elicited by blue light and was under the control ...19921453275
electrophoretic profiles of mitochondrial plasmids in neurospora suggest they replicate by a rolling circle mechanism.migratory behaviour of mitochondrial plasmids from neurospora crassa mauriceville-1c and n. intermediate labelle has been studied by pulsed field gel electrophoresis (pfge). electrophoretic profiles demonstrate that long, linear molecules of a heterogeneous size are the prevailing form of plasmid dna in vivo. circular forms represent less than 8-9% of plasmid dna. single stranded dna regions are abundant and lead to electrophoretic inertia of a significant amount of plasmid dna. these profiles i ...19921387311
arginine transport in mitochondria of neurospora crassa.transport of arginine into mitochondria of neurospora crassa has been studied. arginine transport was found to be saturable (km = 6.5 mm) and to have a ph optimum of ph 7.5. mitochondrial arginine transport appeared to be facilitated transport rather than active transport because: (i) the arginine concentration within the mitochondrial matrix after transport was similar to that of the reaction medium, and (ii) uncouplers and substrates of oxidative phosphorylation did not affect the transport ra ...19921386360
the vacuolar atpase of neurospora crassa.the filamentous fungus neurospora crassa has many small vacuoles which, like mammalian lysosomes, contain hydrolytic enzymes. they also store large amounts of phosphate and basic amino acids. to generate an acidic interior and to drive the transport of small molecules, the vacuolar membranes are densely studded with a proton-pumping atpase. the vacuolar atpase is a large enzyme, composed of 8-10 subunits. these subunits are arranged into two sectors, a complex of peripheral subunits called v1 an ...19921400281
timing of synthesis and cellular localization of two conidiation-specific proteins of neurospora crassa.the process of conidiation in neurospora crassa consists of a series of distinct developmental stages culminating in the formation of multinucleate asexual spores called macroconidia. immunoblotting techniques were used to study the timing of synthesis and cellular localization of con10 and con13, the products of two genes that are expressed during conidiation but not during mycelial growth. both proteins first appear about 8 hr into conidiation; con10 disappears between 2 and 4 hr after germina ...19921386581
direct transfer of molybdopterin cofactor to aponitrate reductase from a carrier protein in chlamydomonas reinhardtii.a chlamydomonas reinhardtii molybdenum cofactor (moco)-carrier protein (cp), capable of reconstituting nitrate reductase activity with apoprotein from the neurospora crassa mutant nit-1, was subjected to experiments of diffusion through a dialysis membrane and gel filtration. cp bonded firmly moco and did not release it efficiently unless aponitrate reductase was present in the incubation mixture. stability of moco bound to cp against air and heat was very similar to that of free-moco released f ...19921644169
de novo synthesis and desaturation of fatty acids at the mitochondrial acyl-carrier protein, a subunit of nadh:ubiquinone oxidoreductase in neurospora crassa.we have cultivated the cel mutant of neurospora crassa defective in cytosolic fatty acid synthesis with [2-14c]malonate and found radioactivity covalently attached to the mitochondrial acyl-carrier protein (acp), a subunit of the respiratory chain nadh:ubiquinone oxidoreductase. we purified the acp by reverse-phase hplc: the bound acyl groups were trans-esterified to methylesters and analyzed by gas chromatography. the saturated c6 to c18 fatty acids and oleic acid were detected. de novo synthes ...19921397269
cytoplasmic location of amino acids 359-440 of the neurospora crassa plasma membrane h(+)-atpase.the topographic location of the region comprising amino acids 359-440 of the neurospora crassa plasma membrane h(+)-atpase has been elucidated using reconstituted proteoliposomes and protein chemical techniques. proteoliposomes containing h(+)-atpase molecules oriented predominantly with their cytoplasmic surface facing outward were cleaved with trypsin and the resulting digest was subjected to centrifugation on a glycerol step gradient to separate the released and liposome-bound peptides. the r ...19921386255
alternative modes of mrna processing in a 3' splice site mutant of neurospora crassa.the am8 mutant of neurospora crassa is shown to have a double base-pair change, gtg for the normal tag, at the 3' end of the second intron of the am (nadp-specific glutamate dehydrogenase, gdh) gene. the greater part of the mutant am transcript accumulates as two fragments hybridising to probes for sequences respectively upstream and downstream of the 5' end of the intron. two processed transcripts approximating to normal full length mrna were identified. in one the second intron was intact; in ...19921535288
ribosomal dna is a site of chromosome breakage in aneuploid strains of neurospora.in wild-type strains of neurospora crassa, the rdna is located at a single site in the genome called the nucleolus organizer region (nor), which forms a terminal segment on linkage group (lg) v. in the quasiterminal translocation strain t(i;v)ar190, most of the right arm of lg i moved to the distal tip of the nor, and one or a few rdna repeat units are moved to the truncated right arm of lg i. i report here that, in partial diploid strains derived from t(i;v)ar190, large terminal deletions resul ...19921385794
sequence and characterization of the met-7 gene of neurospora crassa.the proteins encoded by the met-7+ and met-3+ genes of neurospora crassa are required to form a functional cystathionine-gamma-synthase (cgs). the met-7+ gene has been cloned by complementation of a met-7 mutant. the nucleotide sequence of the complementing dna reveals the presence of a 542-amino acid open reading frame (orf). disruption of this orf abolishes complementation of the met-7 mutation.19921531800
import of cytochrome c heme lyase into mitochondria: a novel pathway into the intermembrane space.cytochrome c heme lyase (cchl) catalyses the covalent attachment of the heme group to apocytochrome c during its import into mitochondria. the enzyme is membrane-associated and is located within the intermembrane space. the precursor of cchl synthesized in vitro was efficiently translocated into isolated mitochondria from neurospora crassa. the imported cchl, like the native protein, was correctly localized to the intermembrane space, where it was membrane-bound. as with the majority of mitochon ...19921371459
binding of a synthetic targeting peptide to a mitochondrial channel protein.membrane crystals of the mitochondrial outer membrane channel vdac (porin) from neurospora crassa were incubated with a 20-amino-acid synthetic peptide corresponding to the n-terminal targeting region of subunit iv of cytochrome oxidase. the peptide caused disordering and contraction of the crystal lattice of the membrane arrays. also, new stain-excluding features were observed on the peptide-treated arrays which most likely correspond to sites at which the peptide accumulates. the stain exclusi ...19921380505
a soluble mitochondrial protein increases the voltage dependence of the mitochondrial channel, vdac.a soluble protein isolated from mitochondria has been found to modulate the voltage-dependent properties of the mitochondrial outer membrane channel, vdac. this protein, called the vdac modulator, was first found in neurospora crassa and then discovered in species from other eukaryotic kingdoms. the modulator-containing fraction (at a crude protein concentration of 20 micrograms/ml) increases the voltage dependence of vdac channels over 2-3-fold. at higher protein concentrations (50-100 microgra ...19921380504
probing the structure of the neurospora crassa plasma membrane h(+)-atpase.the structure of the neurospora crassa plasma membrane h(+)-atpase has been investigated using a variety of chemical and physiochemical techniques. the transmembrane topography of the h(+)-atpase has been elucidated by a direct, protein chemical approach. reconstituted proteoliposomes containing purified h(+)-atpase molecules oriented predominantly with their cytoplasmic surface facing outward were treated with trypsin, and the numerous peptides released were purified by hplc and subjected to am ...19921461258
nit2, the nitrogen regulatory protein of neurospora crassa, binds upstream of nia, the tomato nitrate reductase gene, in vitro.the nit-2 gene of neurospora crassa encodes a trans-acting regulatory protein that activates the expression of a number of structural genes which code for nitrogen catabolic enzymes, including nitrate reductase. the nit2 protein contains a cys2/cys2-type zinc-finger dna-binding domain that recognizes promoter regions of the neurospora nitrogen-related genes. the nit2 zinc-finger domain/beta-gal fusion protein was shown to recognize and bind in a specific manner to two upstream fragments of the n ...19921531184
light and the recovery from heat shock induce the synthesis of 38 kda mitochondrial proteins in neurospora crassa.the effect of light on the protein synthesis pattern in the mitochondria of neurospora crassa was examined by in vivo labelling with [35s]-methionine and two-dimensional gel electrophoresis. a brief 5-min illumination induced the rapid and transient synthesis of a 38-kda protein. white collar-mutants were not stimulated to synthesize this protein by light. a protein of a similar molecular weight and isoelectrical point was synthesized during recovery from heat shock.19921444714
phospholipid content of untreated and insulin treated cells of neurospora crassa (wall-less strain).phosphatidylcholine (51.2%) and phosphatidyl-ethanolamine (38.3%) are the most abundant phospholipids in the wall-less strain of neurospora crassa. insulin treatment exerted no change on the amount of phosphoinositides, although some previous results proved the existence of specific insulin receptors and specific effect of insulin on glucose metabolism in these cells. long (20 h) treatment with insulin also failed to cause biologically significant changes.19921343935
isolation of neurospora crassa a mating type mutants by repeat induced point (rip) mutation.in the filamentous fungus, neurospora crassa, mating type is regulated by a single locus with alternate alleles, termed a and a. the mating type alleles control entry into the sexual cycle, but during vegetative growth they function to elicit heterokaryon incompatibility, such that fusion of a and a hypha results in death of cells along the fusion point. previous studies have shown that the a allele consists of 5301 bp and has no similarity to the a allele; it is found as a single copy and only ...19921398049
molecular cloning of a gene (cfp) encoding the cytoplasmic filament protein p59nc and its genetic relationship to the snowflake locus of neurospora crassa.p59nc is a 59-kd polypeptide associated with 8-10-nm diameter cellular filaments in normal neurospora crassa strains. abnormally sized and shaped bundles of these structures are present in n. crassa strains carrying mutations at the locus sn (snowflake). by using molecular cloning and restriction fragment length polymorphism (rflp) segregation analysis strategies we show here that sn is not the genetic locus of p59nc. several p59nc cdnas were cloned from a n. crassa lambda gt11 library after imm ...19921352758
increase in superoxide production by heat-shocked cells of neurospora crassa, demonstrated by a fluorometric assay.1. increase in superoxide production by heat-shocked cells of neurospora crassa was demonstrated by a fluorometric assay. 2. a sensitive fluorometric assay for the estimation of superoxide anion radical--based on the liberation of 4-methylumbelliferone from 4-methyl-beta-d-umbelliferyl glucopyranoside--is described. 3. using this system the level of superoxide in the medium of heat-shocked neurospora crassa cells was found to be consistently higher, in comparison with that of non-shocked cells, ...19921327889
transformants of neurospora crassa with the nit-4 nitrogen regulatory gene: copy number, growth rate and enzyme activity.nit-4 is a pathway-specific regulatory gene which controls nitrate assimilation in neurospora crassa, and appears to mediate nitrate induction of nitrate and nitrite reductase. the nit4 protein consists of 1090 amino-acid residues and possesses a single gal4-like putative dna-binding domain plus acidic, glutamine-rich, and polyglutamine regions. several mutants with amino-acid substitutions in the putative dna-binding domain and a nit-4 deletion mutant, which encodes a truncated nit4 protein lac ...19921388109
expression of neurospora crassa laccase under the control of the copper-inducible metallothionein-promoter.laccase from the ascomycete neurospora crassa is an inducible secretory enzyme. in vegetatively growing cultures its biosynthesis is repressed but can be induced by different protein synthesis inhibitors. transformation of the n. crassa wild-type strain singapore with a fusion gene consisting of the n. crassa copper-metallothionein promoter and the laccase gene are described in this report. correct integration of the 3.6 kilobase (kb) promoter-fragment fused with the laccase gene containing a 5' ...19921388108
molecular analysis of the neurospora clock: cloning and characterization of the frequency and period-4 genes.genetic analysis of neurospora crassa has identified many mutants that affect the biological clock. in this article we review the cloning of two of these genes, frq and prd-4. both genes were isolated using a chromosome walk technique. subcloning experiments and subsequent northern analysis of frq implicate the importance of two transcripts that emanate from this locus. in preliminary data, no protein-coding region is evident in the smaller transcript; the larger transcript contains a 962-amino ...19921535290
circadian rhythms in neurospora crassa: the role of mitochondria.energy metabolism and mitochondria have been discussed with respect to their role in the circadian rhythm mechanism for some time. numerous examples of inhibitors that affect the mitochondria of plants and animals and microorganisms are known, which cause large phase shifts in the rhythms of these organisms. analogous studies on the role of mitochondria in the neurospora circadian rhythm mechanism have also been reported and summarized. this communication differs from previous studies on other o ...19921535289
a combination inversion and translocation in neurospora crassa with inviable deficiency progeny that can be rescued in heterokaryons.chromosome rearrangement in(il;ir)t(il;iiir)slm-1, has a pericentric inversion in linkage group i associated with a reciprocal translocation between i and iii. the rearrangement was identified cytologically in pairing with normal sequence chromosomes at pachynema. rearrangement breakpoints were mapped genetically in il, ir and iiir by crosses with normal sequence strains and in crosses with an inversion that partially overlaps the slm-1 inversion. when rearrangement slm-1 is crossed to parents w ...19921427036
isolation and characterization of new fluoroacetate resistant/acetate non-utilizing mutants of neurospora crassa.sixty-two mutants of the filamentous fungus neurospora crassa were isolated on the basis of resistance to the antimetabolite fluoroacetate. of these, 14 were unable to use acetate as sole carbon source (acetate non-utilizers, acu) and were the subject of further genetic and biochemical analysis. these mutants fell into four complementation groups, three of which did not complement any known acu mutants. mutants of complementation group 3 failed to complement acu-8, demonstrated similar phenotypi ...19921362582
cot-1, a gene required for hyphal elongation in neurospora crassa, encodes a protein kinase.neurospora crassa is a filamentous fungus that grows on semisolid media by forming spreading colonies. mutations at several loci prevent this spreading growth. cot-1 is a temperature sensitive mutant of n.crassa that exhibits restricted colonial growth. at temperatures above 32 degrees c colonies are compact while at lower temperatures growth is indistinguishable from that of the wild type. restricted colonial growth is due to a defect in hyphal tip elongation and a concomitant increase in hypha ...19921534751
expression of con genes along the three sporulation pathways of neurospora crassa.the filamentous fungus neurospora crassa produces three types of spores by using different developmental pathways: macroconidiation, microconidiation, and sexual spore (ascospore) formation. several genes of unknown function have been cloned by virtue of their expression during macroconidiation but not during mycelial growth (con genes). it had been postulated that expression of the con genes was specific to macroconidiation. to test this assumption, protein extracts from macroconidia, microconi ...19921534304
the basis of decreased recombination in certain outcrosses of neurospora crassa.crossing over in a multiply marked segment of linkage group i was conspicuously reduced in outcrosses between a marked laboratory strain and each of six unrelated wild-collected strains, compared with crosses between inbred laboratory strains. the marked chromosome segment was transferred intact from the inbred strain to one of the wild-collected strains by seven recurrent backcrosses, and conversely, the corresponding segment of the wild strain was transferred to the inbred background by backcr ...19921385584
use of gene replacement transformation to elucidate gene function in the qa gene cluster of neurospora crassa.gene replacement by transformation, employing selective genetic recombination techniques, has been used to delete or disrupt the qa-x, qa-y and qa-1s genes of the qa gene cluster of neurospora crassa. the growth characteristics of the strain carrying the deletion of the qa-y gene support earlier evidence that this gene encodes a quinic acid permease. the strain containing the deletion of the qa-1s gene (delta qa-1s) was examined with respect to quinic acid induction and carbon catabolite repress ...19921533844
a single amino-acid substitution in the beta-tubulin gene of neurospora confers both carbendazim resistance and diethofencarb sensitivity.two mbc-resistant mutants of neurospora crassa, f914 and f939, were sensitive to diethofencarb at a concentration of 0.1 micrograms/ml, while the wild-type strain and other mbc-resistant mutants showed resistance to diethofencarb at a concentration of 100 micrograms/ml. genetic analysis suggested that the mutations in these two strain were closely linked to the bml locus which codes for beta-tubulin. when the wild-type strain was transformed by the cloned beta-tubulin gene of the f914 strain, th ...19921388107
bioelectrorheological model of the cell. 3. viscoelastic shear deformation of the membrane.an analytical electromechanical model of a spherical cell exposed to an alternating electric field was used to calculate shear stress generated in the cellular membrane. shape deformation of neurospora crassa (slime) spheroplasts was measured. statistical analysis permitted empirical evaluation of creep of the cellular membrane within the range of infinitesimal stress. final results were discussed in terms of various rheological models.19921387010
the pho-2a mutant of neurospora crassa which is deficient in pi-repressible alkaline phosphatase (ec 3.1.3.1) is also defective in pi-repressible acid phosphatase (ec 3.1.3.2).1. the mycelial pi-repressible acid phosphatase presented p-nitrophenylphosphatase activity with negative cooperativity and michaelian behavior when synthesized by the wild-type and pho-2a mutant strains of neurospora crassa, respectively. 2. the major acid phosphatase present in cell extracts of the pho-2a mutant of n. crassa grown in low pi medium is more thermolabile (t1/2 = 4 min at 54 degrees c, ph 5.4) than that of the wild strain (stable for at least 80 min at 54 degrees c, ph 5.4). 3. th ...19921342219
effects of light on protein secretion in neurospora crassa.the relative concentrations of secreted proteins in liquid cultures of neurospora crassa differ in constant darkness compared to constant light (2500 lx). light reduces the concentrations of some polypeptides markedly and increases the concentrations of protein species of 67, 40, 18 and 13 kda. the "blind" wc-2 mutant of neurospora does not show light dependent differences in amounts of secreted proteins. one of the light-sensitive extracellular proteins is shown to be a protease of 17.5 kda.19921532303
molecular characterization of mutations of nit-4, the pathway-specific regulatory gene which controls nitrate assimilation in neurospora crassa.the nit-4 genes of three conventional neurospora crassa mutations and of the closely related species, neurospora intermedia, have been isolated by amplifying the genomic dna with the polymerase chain reaction. nucleotide sequencing has revealed that the three nit-4 mutants, alleles 15, 1214, and 2994, are the result of a missense mutation, a nonsense mutation and a frameshift mutation, respectively. the nucleotide sequence of the nit4 protein coding region of a nit-4 mutant (allele 2994) and of ...19921531376
purification of two nitrate reductases from xanthomonas maltophilia grown in aerobic cultures.xanthomonas maltophilia atcc 17666 is an obligate aerobe that accumulates nitrite when grown on nitrate. spectra of membranes from nitrate-grown cells exhibited b-type cytochrome peaks and a(615-630) indicative of d-type cytochrome but no absorption peaks corresponding to c-type cytochromes. the nitrate reductase (nr) activity was located in the membrane fraction. triton x-100-extracted reduced methyl viologen-nrs were purified on de-52, hydroxylapatite, and sephacryl s-300 columns to specific a ...199216348805
isolation and characterization of a new acetate-requiring mutant strain, ace-9, of neurospora crassa.a new acetate-requiring mutant strain of neurospora crassa, ace-9, has been isolated. the mutant gene was mapped between nuc-2 and arg-12 on the right arm of the second linkage group. the ace-9 mutant strain shows very weak activity of pyruvate dehydrogenase complex (pdhc). three strains that show no activity of pdhc had already been found, i.e., ace-2, ace-3, and ace-4. thus the ace-9 is the fourth gene that causes the deficiency in pdhc activity by a mutation. deficiency of pdhc activity in ac ...19921388033
electron transport in the cni-1 mutant of neurospora crassa.1. mitochondria from the nuclear mutant cni-1 have no optically detectable cytochrome aa3 in early log phase growth. these mitochondria have a high level of respiration that is not inhibited by cyanide but is inhibited by salicylhydroxamic acid. they also show a substantial amount of cyanide-sensitive respiration. 2. as cultures of mutant cni-1 age, flux through the hydroxamate-sensitive pathway decreases markedly while flux through the cytochrome chain remains constant. 3. growth studies with m ...1992206437
the state of copper in neurospora laccase.1. neurospora crassa laccase has been prepared from the growth medium and studied by optical absorption, circular dichroism and electron paramagnetic resonance (epr) spectroscopy. the molecular weight, the copper content and the amino acid composition have also been determined. 2. the molecular weight as determined by gel filtration in 6 m guanidine hydrochloride and by sodium dodecyl sulfate gel electrophoresis is found to be 64 000. the enzyme contains 3.8 copper ions per 64 000. 3. the visibl ...1992207349
the role of carbohydrate in the glycoenzyme invertase of neurospora crassa.data obtained concerning the carbohydrate moieties of the glycoenzyme invertase (ec 3.2.1.26, beta-d-fructofuranoside fructohydrolase) from neurospora crassa were consistent with a linkage of some carbohydrate chains by o-glycosidic bonds to serine and threonine residues; the possibility of n-glycosylamine linkage of some of the carbohydrate to the amide group of asparagine is also indicated. the invertase was remarkably stable on storage at low temperatures. oxidation of the carbohydrate residu ...1992195681
new polyenic antibiotics active against gram-positive and gram-negative bacteria. viii. construction of synthetic medium for production of mono-chloro-congeners of enacyloxins.new antibiotics enacyloxins (enxs) are a family of non-lactonic polyene antibiotics produced by frateuria sp. w-315. for the production of antibiotics, we had to employ two-step fermentations, the first is the production of spent medium of neurospora crassa and the second is the production of antibiotics by frateuria. to simplify the production of antibiotics, systematic analyses have been done on the spent medium, and factors which affect the production of antibiotics characterized. from the ab ...19921534321
small subunit ribosomal rna of blastomyces dermatitidis: sequence and phylogenetic analysis.we determined the small subunit (18s) ribosomal rna sequence of the dimorphic fungus blastomyces dermatitidis. the sequence was compared to that of fourteen other eukaryotic organisms, ten of which were higher fungi, and an evolutionary tree was constructed based on these sequences. b. dermatitidis aligned most closely with the ascomycetes neurospora crassa and podospora anserina, in agreement with previous phylogenetic analysis based on morphological criteria. phase-specific cdna clones derived ...19921564447
the dna-binding domain of the cys-3 regulatory protein of neurospora crassa is bipartite.cys-3, the major sulfur regulatory gene of neurospora crassa, encodes a regulatory protein that is capable of sequence-specific interaction with dna. the interaction is mediated by a region within the cys3 protein (the bzip region) which contains a potential dimer-forming surface, the leucine zipper, and an adjacent basic dna contact region, nh2-terminal to the leucine zipper. to investigate the bipartite nature of the bzip region, a series of cys-3 mutants obtained by oligonucleotide-directed m ...19921532511
analysis of junction sequences resulting from integration at nonhomologous loci in neurospora crassa.we have analyzed the junctions involved in two examples of ectopic integration of plasmids containing the am+ (glutamate dehydrogenase) gene into a strain of neurospora crassa bearing a complete deletion of the am locus. in one transformed strain a single copy of plasmid dna had been integrated into linkage group (lg) iii dna without the loss of chromosomal dna. in contrast, 450 bp had been lost from plasmid sequences at the site of integration. the transforming dna used was circular, so we post ...19921533845
[synthesis and antimicrobial activity of chlorobenzyl benzylidene imidazolidinedione derivatives and substituted thiazolidinediones].the synthesis of five chlorobenzyl benzylidene imidazolidinediones and four fluorobenzyl benzylidene thiazolidinediones is described. in order to investigate their antimicrobial activity they are evaluated against microorganism such as candida albicans, neurospora crassa, staphylococcus aureus, mycobacterium smegmatis and escherichia coli.19921615023
identification of a family of bacteriophage t4 genes encoding proteins similar to those present in group i introns of fungi and phage.the bacteriophage t4 sega gene lies in a genetically unmapped region between the gene beta gt (beta-glucosyltransferase) and uvsx (recombination protein) and encodes a protein of 221 amino acids. we have found that the first 100 amino acids of the sega protein are highly similar to the n termini of four other predicted t4 proteins, also of unknown function. together these five proteins, sega-e (similar to endonucleases of group i introns), contain regions of similarity to the endonuclease i-tev ...19921631169
characterization and partial purification of an insulinase from neurospora crassa.an insulin-binding metal- and thiol-dependent proteinase has been purified 1491-fold from high speed cytosolic fractions of the fungus neurospora crassa. this enzyme resembles insulin-degrading enzymes (insulinases) present in mammalian cells and in drosophila melanogaster in the following ways: (i) it degrades radiolabeled insulin with a specificity similar to that of rat muscle insulinase, as demonstrated by hplc analysis of the degradation products; (ii) it is inhibited by bacitracin, edta, 1 ...19921386721
over- and under-representation of short oligonucleotides in dna sequences.strand-symmetric relative abundance functionals for di-, tri-, and tetranucleotides are introduced and applied to sequences encompassing a broad phylogenetic range to discern tendencies and anomalies in the occurrences of these short oligonucleotides within and between genomic sequences. for dinucleotides, ta is almost universally under-represented, with the exception of vertebrate mitochondrial genomes, and cg is strongly under-represented in vertebrates and in mitochondrial genomes. the tradit ...19921741388
cloning and sequence analysis of a rapamycin-binding protein-encoding gene (rbp1) from candida albicans.rapamycin (rm) and fk506 are macrolide antifungal agents that exhibit potent immunosuppressive properties in higher eukaryotes which are mediated through interaction with specific receptor proteins (fkbps or rbps, for fk506- and rm-binding proteins, respectively). these proteins possess peptidyl-prolyl cis-trans isomerase (ppiase) activity in vitro which is inhibited by the binding of rm and fk506. we previously isolated a gene encoding an rbp from saccharomyces cerevisiae, and demonstrated that ...19921563628
characterization of the 9.5-kda ubiquinone-binding protein of nadh:ubiquinone oxidoreductase (complex i) from neurospora crassa.a small polypeptide subunit of the nadh:ubiquinone reductase (complex i) from neurospora crassa has been identified by photoaffinity labeling to participate in the binding of ubiquinone [heinrich, h., & werner, s. (1992) biochemistry (preceding paper in this issue)]. this polypeptide is further characterized by its primary structure and by an assessment of its localization within complex i. a lambda gt11 cdna expression library was screened using a specific antibody directed against this individ ...19921445879
the mating types of podospora anserina: functional analysis and sequence of the fertilization domains.the two idiomorphic alleles called mat+ and mat-, which control the mating types in podospora anserina, have been cloned. mat+ and mat- encompass 3.8 kb and 4.7 kb respectively, of unrelated dna sequences flanked by common sequences. subcloning allowed the identification and localization in each locus of the gene that controls fertilization, probably by determining the mating type. the mat+ gene, called fpr1, encodes a protein with a potential dna-binding hmg domain. the presence of this motif s ...19921534866
characterization of the ilv-2 gene from neurospora crassa encoding alpha-keto-beta-hydroxylacyl reductoisomerase.we have isolated the cdna and corresponding genomic dna for the ilv-2 locus of neurospora crassa. this gene encodes alpha-keto-beta-hydroxylacyl reductoisomerase (ilv-2), required for the synthesis of isoleucine and valine. the gene contains four introns, maps to the right arm of chromosome v, and encodes a protein of 400 amino acids (aa). alignment of the aa sequence of ilv-2 with the two other known eukaryotic sequences encoding this enzyme reveals two conserved regions.19921398116
the cell division cycle gene cdc60 encodes cytosolic leucyl-trna synthetase in saccharomyces cerevisiae.the cdc60 mutation (for cell division cycle) of the yeast, saccharomyces cerevisiae, confers arrest at the start point of the cell cycle upon shift to the restrictive temperature [bedard et al., curr. genet. 4 (1981) 205-214]. we have cloned the cdc60 gene by complementation of the temperature-sensitive phenotype. sequence analysis revealed a single open reading frame of 3270 bp and the deduced amino acid sequence showed 50.5% sequence identity to the cytosolic leucyl-trna synthetase (leurs) fro ...19921398122
characterization of the formate (for) locus, which encodes the cytosolic serine hydroxymethyltransferase of neurospora crassa.serine hydroxymethyltransferase (shmt) occupies a central position in one-carbon (c1) metabolism, catalyzing the reaction of serine and tetrahydrofolate to yield glycine and 5,10-methylenetetrahydrofolate. methylenetetrahydrofolate serves as a donor of c1 units for the synthesis of numerous compounds, including purines, thymidylate, lipids, and methionine. we provide evidence that the formate (for) locus of neurospora crassa encodes cytosolic shmt. the for+ gene was localized to a 2.8-kb bglii f ...19921532227
control of mating type heterokaryon incompatibility by the tol gene in neurospora crassa and n. tetrasperma.the mating-type of neurospora crassa (a and a) have a dual function: a and a individuals are required for sexual reproduction, but only strains of the same mating type will form a stable vegetative heterokaryon. neurospora tetrasperma, in contrast, is a naturally occurring a+a heterokaryon. it was shown previously that the mating-type genes of both species are functionally the same and are not responsible for this difference in heterokaryon incompatibility. this suggests that a separate genetic ...19921535606
[synthesis and structure of substituted bromo and nitrobenzyl benzylidene imidazolidinediones and thiazolidinediones].synthesis and physico-chemical properties of five bromobenzyl-benzylidene-imidazolidinediones and five nitrobenzyl- or benzyl-benzylidene-thiazolidinediones are described. the microbiological activity of bromobenzyl-benzylidene-imidazolidinediones against microorganisms such as candida albicans, neurospora crassa and mycobacterium smegmatis are evaluated.19921471825
neurospora crassa blue-light-inducible gene bli-7 encodes a short hydrophobic protein.blue light induces a number of physiological reactions in neurospora crassa. we have cloned and sequenced the gene bli-7, which is inducible by blue light, and both glucose and nitrogen starvation. this gene is strongly expressed at the rna-level and contributes up to 0.2% of n. crassa total rna when fully induced. the deduced amino acid sequence reveals a short (108 amino acids), hydrophobic protein which has homology to the protein sc-3, encoded by a gene of schizophyllum commune which was iso ...19921472707
sequences of 20 subunits of nadh:ubiquinone oxidoreductase from bovine heart mitochondria. application of a novel strategy for sequencing proteins using the polymerase chain reaction.nadh:ubiquinone oxidoreductase, the first enzyme in the respiratory electron transport chain of mitochondria, is a membrane-bound multi-subunit assembly, and the bovine heart enzyme is now known to contain about 40 different polypeptides. seven of them are encoded in the mitochondrial dna; the remainder are the products of nuclear genes and are imported into the organelle. the primary structures of 12 of the nuclear coded subunits have been described and those of a further 20 are described here. ...19921518044
production of the cys3 regulator, a bzip dna-binding protein, is sufficient to induce sulfur gene expression in neurospora crassa.the cys-3+ gene of neurospora crassa encodes a bzip (basic region-leucine zipper) regulatory protein that is essential for sulfur structural gene expression (e.g., ars-1+). nuclear transcription assays confirmed that cys-3+ was under sulfur-regulated transcriptional control and that cys-3+ transcription was constitutive in sulfur controller (scon)-negative regulator mutants. given these results, i have tested whether expression of cys-3+ under high-sulfur (repressing) conditions was sufficient t ...19921532230
development of a specific-locus assay in the ad-3 region of two-component heterokaryons of neurospora: a review.in recognition of the need for a more comprehensive data base for genetic risk assessment of human exposure to mutagenic agents in the environment, a model system was developed for specific-locus studies in neurospora crassa. this lower eukaryotic organism permits the utilization of microbial techniques for recovery of large numbers of specific-locus mutations at two closely linked loci as well as their subsequent genetic analysis. in particular, this assay makes possible exploratory experiments ...19921425606
the cleavable presequence is not essential for import and assembly of the phosphate carrier of mammalian mitochondria but enhances the specificity and efficiency of import.the phosphate carrier (pic) of mammalian mitochondria is synthesized with a cleavable presequence, in contrast to other members of the mitochondrial family of inner membrane carrier proteins. the precursor of pic is efficiently imported, proteolytically processed, and correctly assembled in isolated mitochondria. here we report that a presequence-deficient pic was imported with an efficiency of about 50% as compared with the authentic precursor of pic. this mature-sized pic was correctly assembl ...19921534805
cloning and sequencing of the cdna encoding tyrosinase of the japanese pond frog, rana nigromaculata.we cloned and sequenced the cdna encoding tyrosinase (tyn) of the japanese pond frog, rana nigromaculata. the 3511-bp cdna contained a 54-bp 5'-noncoding region, a 1596-bp open reading frame encoding tyn of 532 amino acids (aa), and a 1861-bp 3'-noncoding region. the aa sequence of frog tyn predicted from the cdna sequence was homologous to that of mouse and human tyns. the aa sequence including the copper-binding domain, which is likely the active center of tyn, was highly conserved among these ...19921446833
the regulatory gene nit-2 of neurospora crassa complements a nnu mutant of gibberella zeae (fusarium graminearum).the nnu mutant of gibberella zeae (=fusarium graminearum) is unable to catabolize many of the nitrogen sources utilized by its wild-type parent, and may have suffered a mutation in the major nitrogen regulatory locus. transformation of this mutant with the major nitrogen regulatory gene from neurospora crassa, nit-2, restored the wild-type phenotype, thus confirming that the nnu mutation is in the major nitrogen regulatory locus of g. zeae. our results are consistent with the premise of conserva ...19921465117
x-ray-induced specific-locus mutations in the ad-3 region of two-component heterokaryons of neurospora crassa. xi. heterozygous effects of gene/point mutations of genotype ad-3a or ad-3b.previous studies on x-ray-induced irreparable adenine-3 mutants (designated ad-3ir), induced in heterokaryon 12 of neurospora crassa, showed that they were not recessive, and that they demonstrated heterozygous effects in terms of markedly reduced linear growth rates as compared with a wild-type control (de serres, 1965, 1988). homology tests on x-ray-induced irreparable mutants showed that they map, in the main part, as a series of overlapping multilocus deletions that extend both proximally an ...19921381467
characterization of the glyoxysomal isocitrate lyase genes of aspergillus nidulans (acud) and neurospora crassa (acu-3).the nucleotide sequences of the genes encoding the acetate-inducible glyoxylate cycle enzyme isocitrate lyase from the ascomycete fungi aspergillus nidulans (acud) and neurospora crassa (acu-3) are presented. the respective a. nidulans and n. crassa genes are interrupted at identical positions by two introns and encode proteins of 538 and 543 amino acids, which have 75% identity. the predicted protein sequences do not demonstrate the c-terminal tripeptide s-k-l that has been implicated in peroxi ...19921531185
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