| acetylglutamate synthase from neurospora crassa: structure and regulation of expression. | a dna clone which complemented an arg-14 mutation of neurospora crassa was isolated by sib selection from a cosmid library (pmocosx). southern and restriction-fragment-length polymorphism (rflp) analysis confirmed that the cloned dna contained the arg-14 gene. the arg-14 gene was identified as the structural gene for acetylglutamate synthase by immunodepletion of enzyme activity with antibodies prepared against an arg-14 fusion protein and by the thermal instability of acetylglutamate synthase i ... | 1996 | 8939437 |
| loss of growth polarity and mislocalization of septa in a neurospora mutant altered in the regulatory subunit of camp-dependent protein kinase. | in filamentous fungi, growth polarity (i.e. hyphal extension) and formation of septa require polarized deposition of new cell wall material. to explore this process, we analyzed a conditional neurospora crassa mutant, mcb, which showed a complete loss of growth polarity when incubated at the restrictive temperature. cloning and dna sequence analysis of the mcb gene revealed that it encodes a regulatory subunit of camp-dependent protein kinase (pka). unexpectedly, the mcb mutant still formed sept ... | 1996 | 8918454 |
| secondary and tertiary structure changes of reconstituted p-glycoprotein. a fourier transform attenuated total reflection infrared spectroscopy analysis. | the structure of purified p-glycoprotein functionally reconstituted into liposomes was investigated by attenuated total reflection fourier transform infrared spectroscopy. a quantitative evaluation of the secondary structure and a kinetic of 2h/h exchange of the p-glycoprotein were performed both in the presence and in the absence of mgatp, mgatp-verapamil, and mgadp. this approach was previously shown to be a useful tool to detect tertiary structure changes resulting from the interaction betwee ... | 1996 | 8798727 |
| intracellular phosphate--water oxygen exchange measured by mass spectrometry. | to study, in vivo, potential p(i)-water oxygen exchange catalyzed by each of two high-affinity p(i) symporters of neurospora crassa, we have developed methods for the purification of p(i) from whole-cell extracts and the subsequent derivatization of p(i) for analysis by gc-ms. we have also modified a published procedure for the preparation of 18o-p(i). however, the high background rate of transport-independent oxygen exchange, determined by monitoring the appearance of 18o-p(i) in cells incubate ... | 1996 | 8921158 |
| escape from het-6 incompatibility in neurospora crassa partial diploids involves preferential deletion within the ectopic segment. | self-incompatible het-6or/het-6pa partial diploids of neurospora crassa were selected from a cross involving the translocation strain, t(iil-->iiir)ar18, and a normal sequence strain. about 25% of the partial diploids exhibited a marked increase in growth rate after 2 weeks, indicating that "escape" from het-6 incompatibility had occurred. near isogenic tester strains with different alleles (het-6or and het-6pa) were constructed and used to determine that 80 of 96 escape strains tested were het- ... | 1996 | 8889517 |
| mild rip-an alternative method for in vivo mutagenesis of the albino-3 gene in neurospora crassa. | we have used a biological phenomenon that occurs in neurospora crassa, termed repeat-induced point mutation (rip), to create partially functional mutant alleles of the albino-3 (al-3) gene encoding geranylgeranyl pyrophosphate synthase, an enzyme involved in the biosynthesis of carotenoids and diverse prenylated compounds. a total of 70 rip-induced al-3 mutants were identified by their pale albino phenotype, resulting from inactivation of carotenoid bio-synthesis. nucleotide sequence analysis of ... | 1996 | 8879235 |
| bli-4, a gene that is rapidly induced by blue light, encodes a novel mitochondrial, short-chain alcohol dehydrogenase-like protein in neurospora crassa. | blue light plays an important role in developmental control throughout nature. the bli-4 gene of neurospora crassa, together with bli-3, al-1 and al-2, is rapidly inducible by blue light. induction leads to a ninety-fold increase in transcription rate over the dark control level, and the gene therefore appears to be of prime importance in the blue-light induction pathway of n. crassa. we describe the sequencing and analysis of bli-4 and the 38 kda protein it encodes. we show that the protein is ... | 1996 | 8842141 |
| translocation of neurospora crassa transcription factor nuc-1 into the nucleus is induced by phosphorus limitation. | nuc-1, a basic helix-loop-helix zipper protein, activates the expression of several genes involved in phosphorus acquisition in neurospora crassa. in the present study we investigated whether posttranscriptional mechanisms control the activity of nuc-1. the nuc-1 level was higher (up to fivefold) in wild-type cells grown at low external phosphate concentration and in mutant strains expressing the phosphorus acquisition genes constitutively than in a wild-type strain grown at high external phosph ... | 1996 | 8953266 |
| light-induced phase shifting of the circadian conidiation rhythm is inhibited by calmodulin antagonists in neurospora crassa. | the effects of calmodulin antagonists and inhibitors of protein kinases and phosphatases on light-induced phase shifting were investigated in neurospora crassa. calmodulin antagonists, namely, trifluoperazine, chlorpromazine, and w-7, almost completely inhibited the light-induced phase shifting without having any effect on the circadian clock itself. chlorpromazine was less effective in inhibiting the light-induced phase shifting than trifluoperazine. w-5, a dechlorinated analogue of w-7, failed ... | 1996 | 8872595 |
| downstream 28s gene sequences on the rna template affect the choice of primer and the accuracy of initiation by the r2 reverse transcriptase. | r2 non-long terminal repeat retrotransposable elements insert at a unique site in the 28s rrna genes of insects. the protein encoded by the single open reading frame of r2 is capable of conducting the initial steps of its integration in vitro. the protein nicks the noncoding strand of the 28s target dna (the strand which serves as a template for rna synthesis) and uses the 3' hydroxyl group exposed by this nick to prime reverse transcription of the r2 rna template. this target-primed reverse tra ... | 1996 | 8756630 |
| disruption of the nuclear gene encoding the 20.8-kda subunit of nadh: ubiquinone reductase of neurospora mitochondria. | the nuclear gene coding for the 20.8-kda subunit of the membrane arm of respiratory chain nadh: ubiquinone reductase (complex i) from neurospora crassa, nuo-20.8, was localized on linkage group i of the fungal genome. a genomic dna fragment containing this gene was cloned and a duplication was created in a strain of n. crassa by transformation. to generate rip (repeat-induced point) mutations in the duplicated sequence, the transformant was crossed with another strain carrying an auxotrophic mar ... | 1996 | 8804391 |
| evidences for adenine nucleotide binding in the subunits of neurospora mitochondrial processing peptidase. | the mitochondrial processing peptidase (mpp) of neurospora crassa consists of two subunits termed alpha-and beta-mpp. here we present spectroscopic and chromatographic studies indicative of adenine nucleotide binding in the two mpp subunits. adp was identified as the cofactor of alpha-mpp and atp as the cofactor of beta-mpp. the nucleotides are not covalently bound and exert strong control on the conformational and functional properties of the subunits. the adp cofactor of alpha-mpp seems to be ... | 1996 | 8806742 |
| catalytic mechanism of mitochondrial processing peptidase: fluorescence studies. | processing of nuclear-encoded precursor proteins by mitochondrial processing peptidase (mpp) is an essential step for their sorting and function in mitochondria. we report spectroscopic studies on the catalytic mechanism of neurospora crassa mpp. it is a complex enzyme consisting of two different subunits termed alpha-and beta-mpp. following changes in the protein intrinsic fluorescence we register and characterize a complex formation between (i) the alpha- and the beta-subunit of mpp, (ii) the ... | 1996 | 8806741 |
| analysis of the cyt-18 protein binding site at the junction of stacked helices in a group i intron rna by quantitative binding assays and in vitro selection. | the neurospora crassa mitochondrial tyrosyl-trna synthetase (cyt-18 protein) functions in splicing group i introns by promoting the formation of the catalytically active structure of the intron rna. previous studies showed that cyt-18 binds with high affinity to the p4-p6 domain of the catalytic core and that there is some additional contribution to binding from the p3-p9 domain. here, quantitative binding assays with deletion derivatives of the n. crassa mitochondrial large rrna intron showed t ... | 1996 | 8760500 |
| the g alpha i homologue gna-1 controls multiple differentiation pathways in neurospora crassa. | heterotrimeric g proteins are components of principal signaling pathways in eukaryotes. in higher organisms, alpha subunits of g proteins have been divided into four families, gi, gs, gq, and g12. we previously identified a g alpha i homologue gna-1 in the filamentous fungus neurospora crassa. now we report that deletion of gna-1 leads to multiple phenotypes during the vegetative and sexual cycles in n. crassa. on solid medium, delta gna-1 strains have a slower rate of hyphal apical extension th ... | 1996 | 8856670 |
| the product of the het-c heterokaryon incompatibility gene of neurospora crassa has characteristics of a glycine-rich cell wall protein. | filamentous fungi are capable of hyphal fusion, but heterokaryon formation between different isolates is controlled by specific loci termed het loci. heterokaryotic cells formed between strains of different het genotype are rapidly destroyed or strongly inhibited in their growth. in neurospora crassa, at least 11 loci, including the mating type locus, affect the capacity to form a heterokaryon between different isolates. in this report, we describe the molecular characterization of the vegetativ ... | 1996 | 8844148 |
| circular dichroism studies of the mitochondrial channel, vdac, from neurospora crassa. | the protein that forms the voltage-gated channel vdac (or mitochondrial porin) has been purified from neurospora crassa. at room temperature and ph 7, the circular dichoism (cd) spectrum of vdac suspended in octyl beta-glucoside is similar to those of bacterial porins, consistent with a high beta-sheet content. when vdac is reconstituted into phospholipid liposomes at ph 7, a similar cd spectrum is obtained and the liposomes are rendered permeable to sucrose. heating vdac in octyl beta-glucoside ... | 1996 | 8842216 |
| indications for the occurrence of nitric oxide synthases in fungi and plants and the involvement in photoconidiation of neurospora crassa. | indications for the occurrence of nitric oxide synthases in dictyostelium, neurospora, phycomyces and the leguminous plant mucuna hassjoo as well as a physiological role of nitric oxide in neurospora crassa are demonstrated. an exogenous nitic oxide donor, sodium nitroprusside, inhibited light-stimulated conidiation in n. crassa. specific inhibitors of nitric oxide synthase, like the arginine derivatives ng -nitro-l-arginine (l-na) and ng-nitro-l-arginine-methyl ester (l-name), enhanced conidiat ... | 1996 | 8760579 |
| role of the n- and c-termini of porin in import into the outer membrane of neurospora mitochondria. | the signals for targeting and assembly of porin, a protein of the mitochondrial outer membrane, have not been clearly defined. targeting information has been hypothesized to be contained in the n-terminus, which may form an amphipathic alpha-helix, and in the c-terminal portion of the protein. here, the role of the extreme n- and c-termini of porin from neurospora crassa in its import into the mitochondrial outer membrane was investigated. deletion mutants were constructed which lacked the n-ter ... | 1996 | 8706833 |
| meiotic transvection in fungi. | the neurospora crassa asm-1+ (ascospore maturation 1) gene encodes an abundant nucleus-localized protein required for formation of female structures and for ascospore maturation. deletion mutants of asm-1+ are "ascus-dominant," i.e., when crossed to wild type, neither asm-1+ nor asm-1 delta spores mature. to explain this behavior, we considered three models: an effect of reduced dosage of the gene product, failure of internuclear communication, and failure of transvection (regulation dependent o ... | 1996 | 8689677 |
| isolation and characterization of a copper containing protein from blue cell walls of neurospora crassa. | culturing neurospora crassa in presence of toxic amounts of copper (0.63 mm) resulted in blue coloured mycelia and cell walls. significant amounts (approximately 45%) of total mycelial copper were associated with cell wall isolates under conditions of copper toxicity. hence, such blue cell walls were analysed to identify specific ligands involved in copper binding. while decuprification of the blue cell walls with 8-hydroxy quinoline (8 hq) did not alter their copper binding abilities, similar t ... | 1996 | 8979504 |
| purification and characterization of cytochrome c oxidase from the insect trypanosomatid crithidia fasciculata. | cytochrome c oxidase was purified from the mitochondrial lysate of the insect trypanosomatid crithidia fasciculata with the aid of a methyl hydrophobic interaction column in a rapid one-step procedure. the purified complex displayed all characteristics expected from a eukaryotic cytochrome c oxidase: the presence of cua in electron paramagnetic resonance analysis, a characteristic 605 nm peak in reduced-minus-oxidized optical spectroscopy, and the capacity to efficiently oxidize homologous, but ... | 1996 | 8844671 |
| mutants with altered sensitivity to a calmodulin antagonist affect the circadian clock in neurospora crassa. | two newly isolated mutant strains of neurospora crassa, cpz-1 and cpz-2, were hypersensitive to chlorpromazine with respect to mycelial growth but responded differently to the drug with respect to the circadian conidiation rhythm. in the wild type, chlorpromazine caused shortening of the period length of the conidiation rhythm. pulse treatment with the drug shifted the phase and inhibited light-induced phase shifting in neurospora. by contrast to the wild type, the cpz-2 strain was resistant to ... | 1996 | 8807291 |
| isolation and analysis of the arg-13 gene of neurospora crassa. | mutations in arg-13 result in slow growth in minimal medium and can suppress mutations in carbamyl phosphate synthase-aspartate carbamyl transferase within the pyrimidine pathway; the exact biochemical function of the gene product is unknown. to understand the role of arg-13 in arginine metabolism, cosmids rescuing growth in arg-13 mutants were cloned and mapped to the position of arg-13 on lg ir. northern analysis showed the arg-13 message to contain approximately 2100 nt, although a 1.4-kb gen ... | 1996 | 8807290 |
| transgene silencing of the al-1 gene in vegetative cells of neurospora is mediated by a cytoplasmic effector and does not depend on dna-dna interactions or dna methylation. | the molecular mechanisms involved in transgene-induced gene silencing ('quelling') in neurospora crassa were investigated using the carotenoid biosynthetic gene albino-1 (al-1) as a visual marker. deletion derivatives of the al-1 gene showed that a transgene must contain at least approximately 132 bp of sequences homologous to the transcribed region of the native gene in order to induce quelling. transgenes containing only al-1 promoter sequences do not cause quelling. specific sequences are not ... | 1996 | 8670816 |
| molecular cloning of the acr-2 gene which controls acriflavine sensitivity in neurospora crassa. | the acr-2 gene of neurospora crassa was cloned by complementation of the wild-type strain by dna from an acriflavine-resistant strain, acr-2. the transcript of the acr-2 gene is 2.3 kb long and contains two leader open reading frames (orfs) that precede the acr-2 coding region and, if translated, they would generate sequences of 23 and 43 amino acid residues, respectively. the predicted acr-2 protein contains 595 amino acids that include a putative zn(ii)cys6 binuclear domain that is followed by ... | 1996 | 8679704 |
| physical and genetic map of the mitochondrial genome of cryphonectria parasitica ep155. | in the chestnut-blight fungus, cryphonectria parasitica, a cytoplasmically transmissible (infectious) form of hypovirulence is associated with mitochondrial dna (mtdna) mutations that cause respiratory deficiencies. to facilitate the characterization of such mutations, a restriction map including the probable location of 13 genes was constructed for a relatively well-characterized virulent strain of the fungus, ep155. the physical map is based on the order of all fragments generated by cleavage ... | 1996 | 8662207 |
| genetic interactions among cytoplasmic dynein, dynactin, and nuclear distribution mutants of neurospora crassa. | cytoplasmic dynein is a multisubunit, microtubule-associated, mechanochemical enzyme that has been identified as a retrograde transporter of various membranous organelles. dynactin, an additional multisubunit complex, is required for efficient dynein-mediated transport of vesicles in vitro. recently, we showed that three genes defined by a group of phenotypically identical mutants of the filamentous fungus neurospora crassa encode proteins that are apparent subunits of either cytoplasmic dynein ... | 1996 | 8643479 |
| a reverse transcriptase activity in potato mitochondria. | a reverse transcriptase activity has been detected in potato mitochondria using special rnas as templates: a bacterial rna coding for neomycin phosphotransferase (neo pa rna) and a neurospora crassa mitochondrial rna (184 nt rna). surprisingly, no exogenous primer addition was required. these rna templates share a primary and secondary structure similar to the t psi cg loop of trnas that could constitute the recognition site for the enzyme. reverse transcriptase activity was inhibited by ddttp, ... | 1996 | 8756599 |
| p150glued, the largest subunit of the dynactin complex, is nonessential in neurospora but required for nuclear distribution. | dynactin is a multisubunit complex that is required for cytoplasmic dynein, a minus-end-directed, microtubule-associated motor, to efficiently transport vesicles along microtubules in vitro. p150glued, the largest subunit of dynactin, has been identified in vertebrates and drosophila and recently has been shown to interact with cytoplasmic dynein intermediate chains in vitro. the mechanism by which dynactin facilitates cytoplasmic dynein-dependent vesicle transport is unknown. we have devised a ... | 1996 | 8744947 |
| cloning and sequence of the ascobolus immersus s-adenosyl-l-methionine synthetase-encoding gene. | the structural gene encoding s-adenosyl-l-methionine synthetase (sam-s) in the fungus ascobolus immersus has been cloned and sequenced. it contains a 1179-bp orf, interrupted by three introns, encoding a 393-amino-acid protein (42 978 da) that is 90% homologous to the sam-s of the filamentous fungus neurospora crassa, indicating that these fungi are closely related species. | 1996 | 8621082 |
| hyphal development in neurospora crassa: involvement of a two-component histidine kinase. | two-component signal transduction systems are most often found in prokaryotic organisms where they are responsible for mediating the cellular responses to many environmental stimuli. these systems are composed of an autophosphorylating histidine kinase and a response regulator. we have found evidence for the existence of two-component histidine kinases in the eukaryotic filamentous fungus neurospora crassa based on screening with degenerate primers to conserved regions of these signaling protein ... | 1996 | 8622950 |
| purification, kinetic characterization and involvement of tryptophan residue at the nadph binding site of xylose reductase from neurospora crassa. | xylose reductase (xr) from neurospora crassa was purified to homogeneity and was found to be specific to nadph (nicotinamide adenine dinucleotide phosphate). the purified enzyme showed m(r) of 60 and 29 kda by gel filtration and sds-page indicating the presence of two subunits. the kinetic mechanism of xylose reductase is 'iso-ordered bi bi'. inactivation of xr by n-bromosuccinimide (nbs) was found to be biphasic with second-order rate constants of 2.5 x 10(2) and 80 m-1s-1 for the fast (kf) and ... | 1996 | 8620033 |
| a tyrosyl-trna synthetase protein induces tertiary folding of the group i intron catalytic core. | the neurospora crassa mitochondrial tyrosyl-trna synthetase (cyt-18 protein) functions in splicing group i introns. we have used chemical-structure mapping and footprinting to investigate the interaction of the cyt-18 protein with the n. crassa mitochondrial large subunit ribosomal rna (mt lsu) and nd1 introns, which are not detectably self-splicing in vitro. our results show that both these non-self-splicing introns form most of the short range pairings of the conserved group i intron secondary ... | 1996 | 8648621 |
| structural investigation of a cell-wall galactomannan from neurospora crassa and n. sitophila. | | 1996 | 8901273 |
| eth-1, the neurospora crassa locus encoding s-adenosylmethionine synthetase: molecular cloning, sequence analysis and in vivo overexpression. | intense biochemical and genetic research on the eth-1r mutant of neurospora crassa suggested that this locus might encode s-adenosylmethionine synthetase (s-adomet synthetase). we have used protoplast transformation and phenotypic rescue of a thermosensitive phenotype associated with the eth-1r mutation to clone the locus. nucleotide sequence analysis demonstrated that it encodes s-adomet synthetase. homology analyses of prokaryotic, fungal and higher eukaryotic s-adomet synthetase polypeptide s ... | 1996 | 8849888 |
| nutritional and growth control of ribosomal protein mrna and rrna in neurospora crassa. | the effects of changing growth rates on the levels of 40s pre-rrna and two r-protein mrnas were examined to gain insight into the coordinate transcriptional regulation of ribosomal genes in the ascomycete fungus neurospora crassa. growth rates were varied either by altering carbon nutritional conditions, or by subjecting the isolates to inositol-limiting conditions. during carbon up- or down-shifts, r-protein mrna levels were stoichiometrically coordinated. changes in 40s pre-rrna levels paralle ... | 1996 | 8600464 |
| isolation of the vma-6 gene encoding a 41 kda subunit of the neurospora crassa vacuolar atpase, and an adjoining gene encoding a ribosome-associated protein. | the vma-6 gene, encoding a membrane-associated subunit of the vacuolar h+-atpase from neurospora crassa, was cloned and sequenced. the gene contains three small introns and encodes a protein of 41 005 da. when compared with homologous polypeptides from other species, the n. crassa protein contains a unique glycine-rich region. three conserved cysteine residues, previously unrecognized, have been identified. an unrelated gene encoding a protein of 31 701 da was found 2.1 kb downstream of vma-6. t ... | 1996 | 8611592 |
| developmental and photoregulation of three neurospora crassa carotenogenic genes during conidiation induced by desiccation. | neurospora crassa asexual sporulation (conidiation) is induced by different cues including desiccating aerial environments. three of the genes that are expressed during this developmental pathway are the albino (al) genes, which encode carotenoid biosynthetic enzymes. if conidiation is induced by nutrient deprivation in liquid culture, two overlapping al-3 mrnas, al-3 (m) and al-3 (c), are expressed (arpaia et al., 1995, dev. biol. 170, 620-635). here we quantitate accumulation of each of the fo ... | 1997 | 9126619 |
| repeat-induced gene silencing: common mechanisms in plants and fungi. | one of the most surprising observations made in plant science in recent years is the inactivation of transgenes triggered by interactions between dna repeats. in plants, we can differentiate between transcriptional silencing, most likely reflecting a regulation at the dna level, and post-transcriptional silencing that affects steady state rna levels. in the filamentous fungi ascobolus immersus and neurospora crassa, we find two premeiotic silencing processes that are also based on the interactio ... | 1996 | 8868065 |
| activator-independent gene expression in neurospora crassa. | a transgenic position effect that causes activator-independent gene expression has been described previously for three neurospora crassa phosphate-repressible genes. we report analogous findings for two additional positively regulated genes, qa-2+ and ars-1+, indicating that such position effects are not limited to genes involved in phosphorus metabolism. in addition, we have characterized a number of mutants that display activator-independent gene expression. each of these mutants contains a ch ... | 1996 | 8852841 |
| properties of a polynucleotide synthesized by strain 74a of neurospora crassa. | a polynucleotide (or a fragment of rna) was purified to apparent homogeneity by hplc from mycelium of the wild strain 74a of the mould neurospora crassa, after growth on sucrose and in the presence of saturating amounts of inorganic phosphate (pi) for 72 hr at 30 degrees. the m(r) was ca 20,000 as determined by hplc at ph 6.8. polynucleotide synthesis ranged from 4.0 to 6.5 micrograms polynucleotide per mg dry mycelium in mycelium of the wild strain 74a and the various phosphorus regulatory and ... | 1996 | 8821430 |
| bioelectrorheological model of the cell. vi. experimental verification of the rheological model of cytoplasmic membrane. | the susceptibility of the neurospora crassa (slime) cellular membrane to electroporation and electrodestruction in an alternating electric field was further investigated. the results were analyzed according to the dynamic rheological model of the cytoplasmic membrane. based on an analytical description of membrane susceptibility to electroporation, the rheological parameters of the foregoing process in n. crassa cellular membrane were found: they closely resemble those previously determined for ... | 1996 | 8789120 |
| mapping translocation breakpoints by orthogonal field agarose-gel electrophoresis. | orthogonal field agarose-gel electrophoresis (ofage) of chromosomes from translocation-bearing and normal neurospora crassa strains was utilized, first, to recover cosmids from a translocated region, and second, to map translocation breakpoints. surprisingly, the right breakpoints in two independently derived, interstitial translocations, t(ii-->iii) ar18 and t(ii-->vi)p2869, are within about 5.6 kbp of each other suggesting that this region of linkage group (lg) ii may be fragile or otherwise s ... | 1996 | 8595678 |
| distinct cis-acting elements mediate clock, light, and developmental regulation of the neurospora crassa eas (ccg-2) gene. | the neurospora crassa eas (ccg-2) gene, which encodes a fungal hydrophobin, is transcriptionally regulated by the circadian clock. in addition, eas (ccg-2) is positively regulated by light and transcripts accumulate during asexual development. to sort out the basis of this complex regulation, deletion analyses of the eas (ccg-2) promoter were carried out to localize the cis-acting elements mediating clock, light, and developmental control. the primary sequence determinants of a positive activati ... | 1996 | 8552078 |
| the molecular nature of mutations in the mt a-1 gene of the neurospora crassa a idiomorph and their relation to mating-type function. | the 293-amino acid mt a-1 orf of the a mating-type idiomorph of neurospora crassa is multifunctional. it confers a mating identity and is responsible for heterokaryon incompatibility. the goal of this study was to dissect the functional regions of mt a-1. new mutants of mt a-1 selected for loss of the incompatibility function were obtained. one new mutant, a(m)99, was partially fertile as a maternal parent. this is the first time that fertility and incompatibility functions have been separated f ... | 1996 | 8569681 |
| effects of temperature shifts on the activities of neurospora crassa glycogen synthase, glycogen phosphorylase and trehalose-6-phosphate synthase. | conidiospore germlings of neurospora crassa submitted to a heat shock at 45 degrees c accumulate trehalose and degrade glycogen. the opposite occurs upon reincubation at a physiologic temperature (30 degrees c). these observations suggest a temperature-dependent mechanism for the preferential synthesis of one or the other sugar reserve. here we show that concomitant with these shifts of temperature, occurred reversible changes in the activities of glycogen synthase and phosphorylase. glycogen sy ... | 1996 | 8549797 |
| short communication: purification and properties of acid phosphatase (ec 3.1.3.2) secreted by strain 74a of the mould neurospora crassa. | both pi-repressible acid phosphatases, iib (mycelial) and iic (extracellular), synthesized by neurospora crassa and purified to apparent homogeneity by 7.5% page, are monomers, are inhibited by 2 mm zncl2 and are non-specifically stimulated by salts. however, the iic form is activated by p-nitrophenylphosphate (in a negative co-operativity effect with a k 0.5 of 2.5 mm) whereas form iib shows michaelis kinetics, with a k m of 0.5 mm. thus, since both enzymatic forms may be expressed by the same ... | 1996 | 24415104 |
| crystallization and preliminary crystallographic analysis of 3-carboxy-cis,cis-muconate lactonizing enzyme from neurospora crassa. | crystals of 3-carboxy-cis,cis-muconate lactonizing enzyme (cmle; e.c. 5.5.1.5) from neurospora crassa that diffract to high resolution have been obtained. the crystals belong to the orthorhombic space group p2(1)2(1)2(1) with unit-cell dimensions a = 92.1, b = 159.7, c = 236.6 a (at 103 k) and diffract at most to 2 a resolution. the asymmetric unit of the crystals appears to contain two tetrameric cmle molecules making up a total of 328 kda per asymmetric unit. both cross-linking with glutaralde ... | 1996 | 15299752 |
| repeat-induced point mutations of hsp80 gene of neurospora crassa: methylation of duplicated dna sequences in the vegetative state. | the process of repeat-induced point mutations (rip) was used to disrupt the gene encoding the 80-kda heat-inducible protein of neurospora crassa. germinated conidia of the wild-type recipient strain were electrotransformed with a plasmid containing a 7-kb fragment harbouring the complete hsp80 gene sequence. some of the transformants with a duplication of hsp80 gene sequence showed extensive methylation of these sequences even in vegetatively growing cells. the presence of an extra gene copy in ... | 1996 | 9035689 |
| disruption of the nad(+)-specific glutamate dehydrogenase gene of neurospora crassa by means of the rip (repeat-induced point mutations) process. | the structural gene for the catabolite-repressed, substrate-induced nad(+)-specific glutamate dehydrogenase (gdh-1) of neurospora crassa was disrupted using the process of repeat-induced point mutation (rip). plasmids containing incomplete copies of the gene, along with selectable markers, were introduced into germinated conidia by electroporation. the sexual progeny of a transformant containing an ectopically integrated copy of a plasmid, harbouring the 5' flanking region and a part of the codi ... | 1996 | 9035688 |
| cloning and analysis of the alternative oxidase gene of neurospora crassa. | mitochondria of neurospora crassa contain a cyanide-resistant alternative respiratory pathway in addition to the cytochrome pathway. the alternative oxidase is present only when electron flow through the cytochrome chain is restricted. both genomic and cdna copies for the alternative oxidase gene have been isolated and analyzed. the sequence of the predicted protein is homologous to that of other species. the mrna for the alternative oxidase is scarce in wild-type cultures grown under normal con ... | 1996 | 8770590 |
| a uv-induced mutation in neurospora that affects translational regulation in response to arginine. | the neurospora crassa arg-2 gene encodes the small subunit of arginine-specific carbamoyl phosphate synthetase. the levels of arg-2 mrna and mrna translation are negatively regulated by arginine. an upstream open reading frame (uorf) in the transcript's 5' region has been implicated in arginine-specific control. an arg-2-hph fusion gene encoding hygromycin phosphotransferase conferred arginine-regulated resistance to hygromycin when introduced into n. crassa. we used an arg-2-hph strain to selec ... | 1996 | 8770589 |
| conidial alkaline phosphatase from neurospora crassa. | an alkaline phosphatase was purified from conidia of a neurospora crassa wild type strain. the m(r) of the purified native enzyme was estimated as ca 145,000 and 110,000 by gel filtration, in the presence and absence of magnesium ions, respectively. a single polypeptide band of m(r) 36,000 was detected by sds-page, suggesting that the native enzyme was a tetramer of apparently identical subunits. conidial alkaline phosphatase was an acidic protein (pl = 4.0 +/- 0.1), with 40% carbohydrate conten ... | 1996 | 8588877 |
| effects of temperature shifts on the metabolism of trehalose in neurospora crassa wild type and a trehalase-deficient (tre) mutant. evidence against the participation of periplasmic trehalase in the catabolism of intracellular trehalose. | the effects of temperature shifts on the metabolism of trehalose in neurospora crassa were studied in conidiospore germlings of a wild type strain, and of a mutant (tre), deficient in the activity of periplasmic trehalase. when the temperature of the medium was raised from 30 degrees c to 45 degrees c both strains accumulated trehalose, either in media supplemented with glucose or with glycerol as carbon sources. the profiles of glycolysis metabolites suggested that at 45 degrees c glycolysis wa ... | 1995 | 8541310 |
| mutations affecting the biosynthesis of s-adenosylmethionine cause reduction of dna methylation in neurospora crassa. | a temperature-sensitive methionine auxotroph of neurospora crassa was found in a collection of conditional mutants and shown to be deficient in dna methylation when grown under semipermissive conditions. the defective gene was identified as met-3, which encodes cystathionine-gamma-synthase. we explored the possibility that the methylation defect results from deficiency of s-adenosylmethionine (sam), the presumptive methyl group donor. methionine starvation of mutants from each of nine complement ... | 1995 | 8532524 |
| sequence repeat-induced disruption of the major heat-inducible hsp70 gene of neurospora crassa. | the process of repeat-induced point mutation (rip) was used to disrupt hsps-1, the gene encoding the major heat-inducible member of the hsp70 family of neurospora crassa. a plasmid dna, containing an incomplete copy of hsps-1 and the selectable marker qa-2+, was introduced into germinated conidia. the sexual progeny of transformants with ectopically integrated hsps-1 dna was examined for rip by southern-blot analysis of mboi- and sau3a-digested genomic dna. progeny strains, showing rip, were tes ... | 1995 | 8595654 |
| a suppressor mutation which suppresses adenylyl cyclase mutations in neurospora crassa. | a spontaneous suppressor mutant, hah, which suppressed the colonial growth of adenylyl cyclase mutants (cr-1) was isolated. the morphology of cr-1 hah was filamentous, but slightly different from that of wild type on solid medium. the hah strain formed many high aerial hyphae, but did not form any conidia. the expression levels of an adenylyl cyclase gene, nac, in both hah and cr-1 hah were much higher than those in wild type or in cr-1. the level of camp in cr-1 was very low but returned to clo ... | 1995 | 8574907 |
| osmotic effects on the polyamine pathway of neurospora crassa. | in bacteria, mammals, and certain plants, the induction of the polyamine synthetic enzyme, ornithine decarboxylase (odc), and the accumulation of its product, putrescine, follows osmotic manipulations of cells. in at least some of these cases, this response is indispensable for survival. we wished to determine whether the polyamine pathway of neurospora crassa was regulated in response to hyper- or hypoosmotic conditions. unlike odc of most other classes of organisms, the n. crassa enzyme and th ... | 1995 | 8574906 |
| cytogenetics of an intrachromosomal transposition in neurospora. | knowledge of intrachromosomal transpositions has until now been primarily cytological and has been limited to drosophila and to humans, in both of which segmental shifts can be recognized by altered banding patterns. there has been little genetic information. in this study, we describe the genetic and cytogenetic properties of a transposition in neurospora crassa. in tp(ir-->il)t54m94, a 20 map unit segment of linkage group i has been excised from its normal position and inserted near the centro ... | 1995 | 8565702 |
| regulation of the expression of three housekeeping genes encoding subunits of the neurospora crassa vacuolar atpase. | the vacuolar atpase is a complex enzyme and is encoded by at least nine genes, which appear to be scattered throughout the genome. we have examined the vma-1 vma-2, and vma-3 genes, which encode subunits present in multiple copies within the neurospora crassa vacuolar atpase. we wished to see if the expression of these genes is coordinately regulated and if these genes contain similar promoter elements. a region was sequenced of approximately 1 kb located upstream of the protein coding region fo ... | 1995 | 7500957 |
| purification of a heteromeric ccaat binding protein from neurospora crassa. | expression of the neurospora crassa am (nadp-specific glutamate dehydrogenase) gene is controlled by two upstream enhancer-like elements designated ursam alpha and ursam beta. ursam alpha is localized between - 1.3 and - 1.4 kb with respect to the major transcriptional start site. deletion of a 90 bp sequence containing this element resulted in the loss of approximately 50% of normal glutamate dehydrogenase expression. gel mobility shift analysis indicated that a nuclear protein from neurospora ... | 1995 | 7500955 |
| the neurospora organelle motor: a distant relative of conventional kinesin with unconventional properties. | the "conventional" kinesins comprise a conserved family of molecular motors for organelle transport that have been identified in various animal species. organelle motors from other phyla have not yet been analyzed at the molecular level. here we report the identification, biochemical and immunological characterization, and molecular cloning of a cytoplasmic motor in a "lower" eukaryote, the ascomycete fungus neurospora crassa. this motor, termed nkin (for neurospora kinesin), exhibits several un ... | 1995 | 8589459 |
| alterations in growth rate associated with a normally persisting circadian rhythm during spaceflight. | biological clocks time many physiological parameters with periodicities close to 24 h; those which persist in the absence of environmental cues are circadian. an earlier shuttle experiment (sts-9) examined circadian pacemaker function and growth rate of neurospora crassa and demonstrated damped rhythm amplitudes, increased variability in period lengths and altered growth rates. | 1995 | 8588798 |
| chromosome rearrangements that involve the nucleolus organizer region in neurospora. | in approximately 3% of neurospora crassa rearrangements, part of a chromosome arm becomes attached to the nucleolus organizer region (nor) at one end of chromosome 2 (linkage group v). investigations with one inversion and nine translocations of this type are reported here. they appear genetically to be nonreciprocal and terminal. when a rearrangement is heterozygous, about one-third of viable progeny are segmental aneuploids with the translocated segment present in two copies, one in normal pos ... | 1995 | 8582636 |
| binding affinity and functional significance of nit2 and nit4 binding sites in the promoter of the highly regulated nit-3 gene, which encodes nitrate reductase in neurospora crassa. | in the filamentous fungus neurospora crassa, both the global-acting regulatory protein nit2 and the pathway-specific regulatory protein nit4 are required to turn on the expression of the nit-3 gene, which encodes nitrate reductase, the first enzyme in the nitrate assimilatory pathway. three nit2 binding sites and two nit4 binding sites have been identified in the 1.3-kb nit-3 promoter region via mobility shift and footprinting experiments with nit2-beta-galactosidase and nit4-beta-gactosidase fu ... | 1995 | 7592372 |
| quantitative and qualitative aspects of spontaneous specific-locus mutation in the ad-3 region of heterokaryon 12 of neurospora crassa. | the data from forward-mutation experiments to obtain specific-locus mutations at 2 closely linked loci in the adenine-3 (ad-3) region of heterokaryon 12 (h-12) of neurospora crassa have been tabulated to determine the frequency of spontaneous ad-3 mutations and to determine the percentages resulting from each of the 2 major genotypic classes: gene/point mutations and multilocus deletion mutations. gene/point mutations at the ad-3b locus (ad-3br) have been characterized to determine the percentag ... | 1995 | 7500991 |
| inactivation of a single-2a phosphoprotein phosphatase is lethal in neurospora crassa. | a pcr approach, employing the use of degenerate oligonucleotide mixtures, was used to isolate pph-1, a type-2a protein phosphatase (catalytic subunit)-encoding gene, from neurospora crassa. the isolated single copy gene is 1327 nucleotides in length, contains four putative introns and encodes a 310 amino-acid polypeptide. pph-1 is located between pdx-1 and col-4 on the right arm of n.crassa linkage group iv. pph-1 transcript levels are highest during the first hours of conidial germination. fail ... | 1995 | 8575020 |
| dna methylation associated with repeat-induced point mutation in neurospora crassa. | repeat-induced point mutation (rip) is a process that efficiently detects dna duplications prior to meiosis in neurospora crassa and peppers them with g:c to a:t mutations. cytosine methylation is typically associated with sequences affected by rip, and methylated cytosines are not limited to cpg dinucleotides. we generated and characterized a collection of methylated and unmethylated amrip alleles to investigate the connection(s) between dna methylation and mutations by rip. alleles of am harbo ... | 1995 | 7565710 |
| cytochrome c oxidase in neurospora crassa contains myristic acid covalently linked to subunit 1. | radiolabel from [3h]myristic acid was incorporated by neurospora crassa into the core catalytic subunit 1 of cytochrome c oxidase (ec 1.9.3.1), as indicated by immunoprecipitation. this modification of the subunit, which was specific for myristic acid, represents an uncommon type of myristoylation through an amide linkage at an internal lysine, rather than an n-terminal glycine. the [3h]myristate, which was chemically recovered from the radiolabeled subunit peptide, modified an invariant lys-324 ... | 1995 | 7567996 |
| purification of neurospora crassa alkaline phosphatase without dnase activity for use in molecular biology. | alkaline phosphatase, excreted by neurospora crassa preg (c) and purified to apparent homogeneity by 7.5% page, did not show dnaase activity and removed the terminal 5'-phosphate group from plasmid bluescript m13(+) linearized with ecori. the preg (c) strain may therefore replace other sources of alkaline phosphatase for use in dephosphorylating linearized plasmidial dna in cloning experiments. | 1995 | 24414902 |
| crystallization and preliminary x-ray analysis of the nadp-specific glutamate dehydrogenase from neurospora crassa. | the nadp-linked glutamate dehydrogenase from neurospora crassa has been crystallized by the hanging-drop method of vapour diffusion in the presence of 0.1 m glutamate. the crystals are trigonal and are in space group p3(1)21 with unit-cell dimensions of a = b = 196.6, c = 102.0 a and with a trimer in the asymmetric unit. a full structure determination of this enzyme will lead to an understanding of the molecular basis of inter-allelic complementation observed with hybrid hexamers of naturally oc ... | 1995 | 15299820 |
| species-specific and mating type-specific dna regions adjacent to mating type idiomorphs in the genus neurospora. | mating type idiomorphs control mating and subsequent sexual development in neurospora crassa and were previously shown to be well conserved in other neurospora species. the centromere-proximal flanks of the a and a idiomorphs, but not the distal flanks from representative heterothallic, pseudohomothallic, and homothallic neurospora species contain apparent species-specific and/or mating type-specific sequences adjacent to the well-conserved idiomorphs. the variable flank is bordered by regions t ... | 1995 | 8536961 |
| mechanism of pyrithione-induced membrane depolarization in neurospora crassa. | pyrithione is a general inhibitor of membrane transport in fungi and is widely used in antidandruff shampoos as an antifungal agent. an electrophysiological approach has been used to determine the mode of action of pyrithione on the plasma membrane of the model ascomycete, neurospora crassa. at ph 5.8, pyrithione induces a dramatic dose-dependent electrical depolarization of the membrane which is complete within 4 min, amounts to 110 mv at saturating pyrithione concentrations, and is half maxima ... | 1995 | 7574648 |
| three-to-one segregation from reciprocal translocation quadrivalents in neurospora and its bearing on the interpretation of spore-abortion patterns in unordered asci. | in neurospora, viable ascospores become black (b) when mature, whereas ascospores that are deficient for a chromosome segment are inviable and usually fail to blacken. the presence of a chromosome rearrangement can be recognized and the type of rearrangement can usually be inferred by visual inspection of asci. when a cross is heterozygous for a reciprocal translocation, asci with eight black ascospores (8b:0w) and asci with eight abortive unpigmented ("white" (w)) ascospores (0b:8w) are theoret ... | 1995 | 7672602 |
| characterization of the promoter region of a cell-adhesion protein gene derived from the basidiomycete lentinus edodes. | an analysis of the 2 kb nucleotide sequence including the 5'-flanking region of a cell-adhesion protein-encoding gene (mfba) isolated from the basidiomycete lentinus edodes revealed that the promoter region contains a tata box, a gc box, a caat box, a ct-rich sequence element, a tata box, two ct-rich sequences, and a caat box, in the order, from upstream to downstream. three major and three alternative transcriptional initiation sites were located 127, 129 and 131 nucleotides and 96, 193 and 197 ... | 1995 | 7649440 |
| light and development regulate the expression of the albino-3 gene in neurospora crassa. | the albino-3 gene of neurospora crassa codes for geranylgeranyl pyrophosphate synthase, an enzyme involved in the biosynthesis of carotenoids. the albino-3 locus encodes two overlapping transcription units that give rise to two mrnas of 2.2 kb (al-3(c)) and 1>6 kb (al-3(m)), with the promoter of the latter residing in the transcribed region of the former. the 1.6-kb transcript was transiently expressed in the mycelium after light induction, while the 2.2-kb mrna appeared in conidiating cultures ... | 1995 | 7649389 |
| fourier transform infrared spectroscopy study of the secondary structure of the reconstituted neurospora crassa plasma membrane h(+)-atpase and of its membrane-associated proteolytic peptides. | we reconstituted purified plasma membrane h(+)-atpase from neurospora crassa into soybean phospholipid vesicles (lipid/atpase ratio of 5:1 w/w). the proteoliposomes contained an active atpase, oriented inside-out. they were subjected to proteolysis by using pronase, proteinase k, trypsin, and carboxypeptidase y. fourier transform infrared attenuated total reflection spectroscopy indicates that the amount of protein remaining after hydrolysis and elimination of the extramembrane domain of atpase ... | 1995 | 7629067 |
| a chimeric light-regulated amino acid transport system allows the isolation of blue light regulator (blr) mutants of neurospora crassa. | we have developed a system for the isolation of neurospora crassa mutants that shows altered responses to blue light. to this end we have used the light-regulated promoter of the albino-3 gene fused to the neutral amino acid permease gene mtr. the product of the mtr gene is required for the uptake of neutral aliphatic and aromatic amino acids, as well as toxic analogs such as p-flurophenylalanine or 4-methyltryptophan. mtr trp-2-carrying cells were transformed with the al-3 promoter-mtr wild-typ ... | 1995 | 7604041 |
| the chromosomal region which includes the recombinator cog in neurospora crassa is highly polymorphic. | the st lawrence st74-or23-iva and lindegren y8743 strains of neurospora crassa have a different provenance from wild collections and dissimilar cog alleles; that in lindegren, cogla (previously designated cog+), is a more efficient recombinator than cogs74a and cogea (previously cog), the alleles in st lawrence and emerson a respectively. restriction fragment length polymorphisms (rflps) and sequence polymorphisms (sps) were used to map the difference between cogla and cogs74a to a region that e ... | 1995 | 8590467 |
| analysis of the iron-sulfur clusters within the complex i (nadh:ubiquinone oxidoreductase) isolated from potato tuber mitochondria. | the mitochondrial complex i (nadh:ubiquinone oxidoreductase) isolated from potato (solanum tuberosum) has been investigated for the presence of iron-sulfur clusters. epr spectroscopic analysis detected signals arising from clusters n1, n2, n3 and n4. quantitation of the content of iron and sulfur within the isolated complex i showed the preparation to contain 22.6 mol acid-labile sulfide and 30.4 mol iron/mol complex i. the iron-sulfur cluster composition of the plant complex i appears to be sim ... | 1995 | 7601133 |
| a fungal actin-related protein involved in nuclear migration. | the ro-4 mutant of the filamentous fungus neurospora crassa forms distinctive colonies in which hyphae grow into rope-like aggregates. this unusual morphology coincides with a defect in hyphal nuclear migration. the ro-4 gene was cloned from a cosmid library by complementation of the closely linked pab-2 gene. the deduced 380 amino acid protein is most similar to the vertebrate actin-related protein/centractin. the ro4 protein is not essential for cell viability, and new strains created by induc ... | 1995 | 7603438 |
| redox imbalance at the start of each morphogenetic step of neurospora crassa conidiation. | the conidiation process of neurospora crassa is characterized by three morphogenetic steps: hyphal adhesion, aerial hyphal formation, and production of conidia. total protein oxidation and specific enzyme oxidation coincided with an increased oxygen-dependent chemiluminescence and indicated the occurrence of a hyperoxidant state at the onset of all three morphogenetic steps. oxidation of nad(p)h and excretion of glutathione disulfide was detected at the start of hyphae adhesion. here we show tha ... | 1995 | 7786037 |
| solubilization of neurospora crassa rodlet proteins and identification of the predominant protein as the proteolytically processed eas (ccg-2) gene product. | proteins from conidial rodlet preparations of neurospora crassa were solubilized in trifluoroacetic acid. sodium dodecyl sulfate-polyacrylamide gel electrophoresis of solubilized rodlets revealed a predominant protein of approximately 7 kda. this protein was absent from preparations of n. crassa cultures carrying the eas mutation. the protein was purified by reverse-phase high-performance liquid chromatography and the n-terminal amino acid sequence of the purified protein was found to be identic ... | 1995 | 7614378 |
| resistance to azole drugs in neurospora crassa. | neurospora crassa was susceptible to azole drugs: ketoconazole (mic 1 microgram/ml), fluconazole (mic 5 micrograms/ml), and sch39304 (mic 5 micrograms/ml). mutants of n. crassa resistant to ketoconazole were selected and genetically characterized. the seven characterized resistance mutations represented at least four genetic loci. some mutants, but not all, were also resistant to fluconazole and to sch39304. | 1995 | 7614377 |
| [analysis of light signal transmission through the phosphorylation of proteins in neurospora crassa]. | | 1995 | 7610259 |
| translocation of apocytochrome c across the outer membrane of mitochondria. | apocytochrome c follows a unique pathway into mitochondria. import does not require the general protein translocation machinery, protease-sensitive components of the outer membrane, or a membrane potential across the inner membrane. we investigated the membrane binding and translocation steps of the import reaction using purified outer membrane vesicles (omv) from neurospora crassa mitochondria. omv specifically bound, but did not import apocytochrome c. if, however, specific antibodies were enc ... | 1995 | 7759479 |
| reconstitution of the neurospora crassa plasma membrane h(+)-adenosine triphosphatase. | the purified h(+)-atpase of the neurospora crassa plasma membrane has been reconstituted by a gel filtration method into lipidic vesicles using sodium deoxycholate as the detergent. reconstitution was performed for lipid/atpase ratios ranging from 1000:1 to 5:1 (w/w). whatever the lipid/atpase ratio, the atpase molecules completely associate with the lipid vesicles. the atpase specific activity is identical for all proteoliposomes regardless of the lipid/atpase ratio, but the h+ transport decrea ... | 1995 | 7794959 |
| developmental and photoregulation of al-1 and al-2, structural genes for two enzymes essential for carotenoid biosynthesis in neurospora. | the levels of al-1 and al-2 transcripts change dramatically in response to light and development during the formation of neurospora crassa asexual spores (conidia). al-1 and al-2 mrnas accumulate throughout conidiation irrespective of lighting conditions initially at low levels. as conidiation proceeds, two increases in albino message accumulation are observed. this developmentally induced photoindependent message accumulation was not observed in neurospora mutants blocked at relevant stages of ... | 1995 | 7750660 |
| 2-d structure of the neurospora crassa plasma membrane atpase as determined by electron cryomicroscopy. | large, well-ordered 2-d crystals of the dodecylmaltoside complex of the neurospora crassa plasma membrane h(+)-atpase grow rapidly on the surface of a polyethylene glycol-containing mixture similar to that originally developed for growing 3-d crystals of this integral membrane transport protein. negative stain electron microscopy of the crystals shows that many are single layers. cryoelectron microscopy of unstained specimens indicates that the crystals have a p6 layer group with unit cell dimen ... | 1995 | 7743992 |
| cyclophilin 20 is involved in mitochondrial protein folding in cooperation with molecular chaperones hsp70 and hsp60. | we studied the role of mitochondrial cyclophilin 20 (cyp20), a peptidyl-prolyl cis-trans isomerase, in preprotein translocation across the mitochondrial membranes and protein folding inside the organelle. the inhibitory drug cyclosporin a did not impair membrane translocation of preproteins, but it delayed the folding of an imported protein in wild-type mitochondria. similarly, neurospora crassa mitochondria lacking cyp20 efficiently imported preproteins into the matrix, but folding of an import ... | 1995 | 7739545 |
| light induction of the clock-controlled gene ccg-1 is not transduced through the circadian clock in neurospora crassa. | ambient light and the circadian clock have been shown to be capable of acting either independently or in an interrelated fashion to regulate the expression of conidiation in the ascomycete fungus neurospora crassa. recently several molecular correlates of the circadian clock have been identified in the form of the morning-specific clock-controlled genes ccg-1 and ccg-2. in this paper we report studies on the regulation of ccg-1, an abundantly expressed gene displaying complex regulation. consist ... | 1995 | 7753024 |
| the sulfur controller-2 negative regulatory gene of neurospora crassa encodes a protein with beta-transducin repeats. | the sulfur regulatory system of neurospora crassa is composed of a set of structural genes involved in sulfur catabolism controlled by a genetically defined set of trans-acting regulatory genes. these sulfur regulatory genes include cys-3+, which encodes a basic region-leucine zipper transcriptional activator, and the negative regulatory gene scon-2+. we report here that the scon-2+ gene encodes a polypeptide of 650 amino acids belonging to the expanding beta-transducin family of eukaryotic regu ... | 1995 | 7724564 |
| guest: a 98 bp inverted repeat transposable element in neurospora crassa. | the region immediately 3' of histidine-3 has been cloned and sequenced from two laboratory strains of the ascomycete fungus neurospora crassa; st lawrence 74a and lindegren, which have different derivations from wild collections. amongst the differences distinguishing these sequences are insertions ranging in size from 20 to 101 bp present only in st lawrence. the largest of these is flanked by a 3 bp direct repeat, has terminal inverted repeats (tir) and shares features with several known trans ... | 1995 | 7715596 |
| some property of the nucleus determines the competence of neurospora crassa for transformation. | in neurospora, transformation of spheroplasts is quite efficient and usually occurs with the transforming dna integrated at ectopic sites in the chromosome. however, only a small fraction of the spheroplasts is actually competent for transformation. to distinguish whether the limitation to competence is at the level of the plasma membrane or at the level of the nucleus, we performed experiments in which heterocaryotic spheroplasts were required to integrate two different plasmids in one transfor ... | 1995 | 7789759 |
| cloning, nucleotide sequence, and expression of tef-1, the gene encoding translation elongation factor 1 alpha (ef-1 alpha) of neurospora crassa. | the tef-1 gene encoding translation elongation factor 1 alpha was cloned from the ascomycete fungus neurospora crassa. the sequences of genomic dna and cdna clones showed that the tef-1 gene contained one orf of 1380 bp length that is interrupted by three short introns. the deduced polypeptide contained 460 amino acid residues, and the sequence had a high similarity with those of ef-1 alpha polypeptides from other species. the level of tef-1 mrna was low in conidia but high in growing cells. whe ... | 1995 | 7605676 |
| 'sheltered disruption' of neurospora crassa mom22, an essential component of the mitochondrial protein import complex. | mom22 is a component of the protein import complex of the mitochondrial outer membrane of neurospora crassa. using the newly developed procedure of 'sheltered disruption', we created a heterokaryotic strain harboring two nuclei, one with a null allele of the mom-22 gene and the other with a wild-type allele. homokaryons bearing the mom-22 disruption could not be isolated, suggesting that mom-22 is an essential gene. the mutant nucleus can be forced to predominate in the heterokaryon through the ... | 1995 | 7720701 |
| close correlation between heat shock response and cytotoxicity in neurospora crassa treated with aliphatic alcohols and phenols. | in neurospora crassa the aliphatic alcohols methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, isobutanol, ethylene glycol, glycerol, and allyl alcohol and the phenolic compounds phenol, hydroquinone, resorcinol, pyrogallol, phloroglucinol, sodium salicylate, and acetylsalicylic acid were analyzed with respect to their capacities to induce heat shock proteins (hsp) and to inhibit protein synthesis. both the alcohols and phenols showed the greatest levels of hsp induction at concent ... | 1995 | 16534981 |
| inactivation of genes encoding subunits of the peripheral and membrane arms of neurospora mitochondrial complex i and effects on enzyme assembly. | we have isolated and characterized the nuclear genes encoding the 12.3-kd subunit of the membrane arm and the 29.9-kd subunit of the peripheral arm of complex i from neurospora crassa. the former gene was known to be located in linkage group i and the latter is now assigned to linkage group iv of the fungal genome. the genes were separately transformed into different n. crassa strains and transformants with duplicated dna sequences were isolated. selected transformants were then mated with other ... | 1995 | 7768434 |
| genetic nomenclature guide. neurospora crassa. | | 1995 | 7660461 |