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sequence analysis of mitochondrial dna from podospora anserina. pervasiveness of a class i intron in three separate genes.a 48 kb region of the 95 kb mitochondrial genome of podospora anserina has been mapped and sequenced (1 kb = 10(3) base-pairs). the dna sequence of the genes for nd2, 3, 4, atpase 6 and urfc are presented here. as in neurospora crassa, the nd2 and 3 genes consist of a unit separated by one taa stop codon. nd3, 4 and atpase 6 are interrupted by class i introns. all three introns are remarkably similar in the c-domain of their secondary structure, sufficient enough to designate them as new subgrou ...19882975708
molecular organisation of the quinic acid utilization (qut) gene cluster in aspergillus nidulans.the functional integrity of the qutb gene (encoding quinate dehydrogenase) has been confirmed by transformation of a qutb mutant strain. the dna sequence of the contiguous genes qutd (quinate permease), qutb and qutg (function unknown) has been determined and analysed, together with that of qute (catabolic 3-dehydroquinase). the qutb sequence shows significant homology with the shikimate dehydrogenase function of the complex arom locus of aspergillus nidulans, and with the qa-3 quinate dehydroge ...19882976880
the amino acid sequence of ribonuclease n1, a guanine-specific ribonuclease from the fungus neurospora crassa.the complete amino acid sequence of ribonuclease n1 (rnase n1), a guanine-specific ribonuclease from a fungus, neurospora crassa, was determined by conventional protein sequencing, using peptide fragments obtained by tryptic digestion of cyanogen bromide-treated rnase n1 and by staphylococcus aureus v8 protease digestion of heat-denatured rnase n1. the results showed that the protein is composed of a single polypeptide chain of 104 amino acid residues cross-linked by two disulfide bonds and has ...19882977130
chemical synthesis and expression of copper metallothionein gene of neurospora crassa.the gene coding for the neurospora crassa copper metallothionein (mt) was synthesized and inserted in the lacz' gene of puc18 plasmid to give the same translational reading frame as the latter gene. the mt-beta-galactosidase fused gene was expressed in escherichia coli to produce a fused protein in which the amino and carboxy termini of mt are linked to the beta-galactosidase through methionine residues. an mt derivative containing an extra homoserine residue at the carboxy terminus was prepared ...19882977386
high-performance liquid chromatography of siderophores from fungi.a reversed-phase hplc separation of iron(iii) chelates of 16 representative fungal siderophores including ferrichromes, coprogens and triacetylfusarinine c was established in order to investigate siderophore production of fungi. for comparison purposes, the widely used bacterial siderophore ferrioxamine b was included. culture filtrates of the fungi penicillium resticulosum, fusarium dimerum, aspergillus fumigatus and neurospora crassa were quantitatively analyzed for the presence of known and u ...19882978959
assembly of functional proton-translocating atpase complex in yeast mitochondria with cytoplasmically synthesized subunit 8, a polypeptide normally encoded within the organelle.a mitochondrial gene from saccharomyces cerevisiae encoding a hydrophobic membrane protein, subunit 8 of the f0/f1-type mitochondrial atpase complex, has been functionally replaced by an artificial nuclear gene specifying an imported version of this protein. the experiments reported here utilized a multicopy expression vector (plf1) that replicates in the nucleus of yeast cells and that carries an inserted dna segment, specifying a precursor protein (n9/y8) consisting of subunit 8 fused to an n- ...19882895470
reprogrammed expression of subunit 9 of the mitochondrial atpase complex of saccharomyces cerevisiae. expression in vitro from a chemically synthesized gene and import into isolated mitochondria.a synthetic gene has been designed and constructed by total chemical synthesis as a first step in the functional relocation from the mitochondrion to the nucleus of a gene encoding subunit 9 of the yeast mitochondrial atpase complex. this gene (nap9) incorporates codons frequently used in nuclear genes of saccharomyces cerevisiae and additionally includes a series of unique restriction enzyme cleavage sites to facilitate future systematic manipulations of the gene and its protein product. follow ...19882895707
studies on the import into mitochondria of yeast atp synthase subunits 8 and 9 encoded by artificial nuclear genes.direct fusions have been constructed between each of subunits 8 and 9 from mitochondrial atpase of saccharomyces cerevisiae, proteins normally encoded inside mitochondria, and the cleavable n-terminal transit peptide from the nuclearly encoded precursor to subunit 9 of neurospora crassa mitochondrial atpase. the subunit 8 construct was imported efficiently into isolated yeast mitochondria and was processed at or very near the fusion point. when expressed in vivo from its artificial nuclear gene, ...19882900779
biosynthesis of the plasma membrane h+-atpase of neurospora crassa.the plasma membrane h+-atpase of neurospora is a 100-kda integral membrane protein which appears, on the basis of hydropathy analysis of its amino acid sequence, to span the lipid bilayer at least eight times. to investigate the assembly and processing of the atpase, a full-length cdna has been constructed for use in in vitro transcription and translation experiments. comparison of three different forms of the atpase (nascent protein, nascent protein cotranslationally inserted into membranes, an ...19882902084
effects of mammalian insulin on metabolism, growth, and morphology of a wall-less strain of neurospora crassa.addition of mammalian insulin to a nutritionally rich, chemically defined culture medium affects neurospora crassa "slime" (wall-less) cells, as indicated by enhancement of growth, extension of viability at the stationary phase of growth, alteration of morphology, and stimulation of glucose oxidation. bovine, porcine, and recombinant human insulin had similar effects on growth and morphology, while proinsulin, reduced insulin, and several other proteins were inactive. insulin added in the presen ...19882962851
stimulation by mammalian insulin of glycogen metabolism in a wall-less strain of neurospora crassa.addition of bovine insulin to cells of the wall-less variant fgsc4761 of neurospora crassa ("slime") produced several significant effects on glycogen metabolism. 1) intracellular levels of the glycogen precursor udp-glucose decreased 17-18% (p less than 0.01) within 30 min of insulin addition. 2) cells grown with insulin possessed 40% more glycogen than did control cells. 3) the incorporation of 14c-labeled glucose into glycogen increased 41% after 30-min treatment with 100 nm bovine insulin (p ...19882962852
neurospora tryptophan synthase. characterization of the pyridoxal phosphate binding site.tryptophan synthase, which catalyzes the final step of tryptophan biosynthesis, is a multifunctional protein that requires pyridoxal phosphate for two of its three distinct enzyme activities. tryptophan synthase from neurospora crassa, a homodimer of two 75-kda subunits, was shown to bind 1 mol of pyridoxal phosphate/mol of subunit with a calculated dissociation constant for pyridoxal phosphate of 1.1 microm. the spectral properties of the holoenzyme, apoenzyme, and reconstituted holoenzyme were ...19882966157
damage-resistant dna synthesis in eukaryotes.the molecular basis of sensitivity of ionizing radiation and other damaging agents is not clearly defined in eukaryotes. while a large number of mutants have been described only a few have been demonstrated to have a defect in the repair of damage to dna. an interesting characteristic of a sub-group of these mutants, in different species extending throughout the phylogenetic scale, is the presence of damage-resistant dna synthesis. this phenomenon is observed in cells from individuals with the g ...19882966294
effect of the homokaryotic state of the uvs-2 allele in neurospora crassa on formaldehyde-induced killing and ad-3 mutation.formaldehyde was tested for its killing and mutagenic activities in the ad-3 forward-mutation test in neurospora crassa. the test was conducted in 3 two-component heterokaryons (dikaryons) of n. crassa in order to determine the effect of the uvs-2 allele, which causes a defect in nucleotide excision repair, on formaldehyde-induced killing and the induction of ad-3 mutants. these dikaryons were homokaryotic for uvs-2+ (h-12), homokaryotic for usv-2 (h-59), and heterokaryotic for uvs-2 (h-71). for ...19882966296
expression of heat shock genes of neurospora crassa: effect of hyperthermia and other stresses on mrna levels.neurospora crassa mycelium was heat shocked for intervals varying from 15-180 min. heat shock mrna was monitored by hybridization of northern blots with the drosophila hsp-70 gene probe and an inducible member of the yeast hsp-70 gene family, yg100. a 2.7 kilobase (kb) transcript, with homology to these two probes, was detected in cultures shocked for 15 min; its levels increased up to 60-90 min and declined thereafter. sodium arsenite, too, induced the synthesis of this transcript. an additiona ...19882967081
evolutionary relationships among copper proteins containing coupled binuclear copper sites.the amino acid sequences of different copper proteins containing coupled binuclear copper centers are compared. hemocyanins from arthropods and molluscs and tyrosinases from three different species were found to share a highly homologous region in the c-terminal parts. this region contains three invariant histidines previously identified as ligands to cu(b) in panulirus interruptus hemocyanin by x-ray crystallography (gaykema et al., nature 309, 23-29 (1984]. in contrast, the ligand environment ...19883136463
dnas of the two mating-type alleles of neurospora crassa are highly dissimilar.the mating-type alleles a and a of neurospora crassa control mating in the sexual cycle and function in establishing heterokaryon incompatibility in the vegetative cycle. the a and a alleles were cloned, and they were shown to encode both the sexual functions and vegetative incompatibility. the mating-type clones contain nonhomologous dna segments that are flanked by common dna sequences. neurospora crassa and all heterothallic and pseudohomothallic neurospora species contain a single copy of on ...19882840740
organization of the ribosomal rna genes of schizophyllum commune.the 18, 5.8, 25 and 5s ribosomal rna (rrna) cistrons have been mapped on the ribosomal dna (rdna) unit repeat of schizophyllum commune strain 4-40. these genes are spatially ordered in the sequence given. the presence of a large primary precursor rrna which is processed to form the mature 18, 5.8 and 25s rrnas has been demonstrated. we have mapped the site of transcriptional initiation for this rrna primary precursor. the sequence surrounding this site has been determined and shown to be highly ...19882841031
informational parameters and randomness of mitochondrial dna.the informational content of genomes of nuclear and mitochondrial origin is examined. by using the parameters of shannon's information theory the language of mitochondrial dna is shown to be more similar to the language of bacterial dna than to that of nuclear dna in more evolutionarily advanced animals. moreover, using the parameters of kolmogorov's theory on randomness, genes of different organisms (neurospora crassa and saccharomyces cerevisiae) coding for the same protein (subunit 9 of atpas ...19882842512
the isolation of demolybdo xanthine oxidase from bovine milk.it was deduced many years ago from indirect evidence that demolybdo xanthine oxidase is present in normal bovine milk. this has now been confirmed by isolation of this enzyme form by a method based on the folate-gel affinity-chromatography procedure described nishino & tsushima [(1986) j. biol. chem. 261, 11242-11246]. enzymic and spectroscopic properties of demolybdo xanthine oxidase, which retains flavin and iron-sulphur centres, are generally in accordance with expectations. like the normal e ...19882850803
dna sequence and organization of the mitochondrial nd1 gene from podospora anserina: analysis of alternate splice sites.earlier, we reported that the nd1 mitochondrial gene of podospora anserina is mosaic, containing at least three class i introns. we have now completed the sequence of the nd1 gene and have determined that it contains four class i introns of 1,820, 2,631, 2,256 and 2,597 bp with the entire gene complex containing 10,505 bp, only 1,101 of which are exon sequences. introns 1 and 3 appear to be related in that their open reading frames (orfs) exhibit extensive amino acid sequence similarity and like ...19883197134
the gene for rat uncoupling protein: complete sequence, structure of primary transcript and evolutionary relationship between exons.the complete nucleotide sequence of rat uncoupling protein gene has been determined. 4.5 kb of the 5'-flanking region have also been sequenced. the site of transcription start as well as 3'-end extremities were identified. transcription unit spans 8.4 kb and contains 6 exons and 5 introns. uncoupling protein as well as related mitochondrial carriers such as adp/atp carrier and phosphate carrier has a triplicated structure and each repeat of uncoupling protein corresponds to 2 exons. two gene dup ...19883202878
microorganisms associated with mouldiness of dried yam chips and their prevention.the broad objective of this study was to isolate and identify the microorganisms causing mouldiness of stored yam chips and to look for ways of preventing the problem. microorganisms isolated included aspergillus flavus, a. glaucus, a. nidulans, a. niger, a. ochraceous, a. tamarii, a. candidus, penicillium oxalicum, trichoderma longibrachyatum, rhizopus nigricans, cylindrocarpon radicicola, neurospora crassa, botryodiplodia theobromae, bacillus subtilis, bacillus cereus, erwinia carotovora and s ...19883231261
sequencing and overexpression of the escherichia coli aroe gene encoding shikimate dehydrogenase.the escherichia coli aroe gene encoding shikimate dehydrogenase was sequenced. the deduced amino acid sequence was confirmed by n-terminal amino acid sequencing and amino acid analysis of the overproduced protein. the complete polypeptide chain has 272 amino acid residues and has a calculated mr of 29,380. e. coli shikimate dehydrogenase is homologous to the shikimate dehydrogenase domain of the fungal arom multifunctional enzymes and to the catabolic quinate dehydrogenase of neurospora crassa.19883277621
purification and properties of escherichia coli dimethyl sulfoxide reductase, an iron-sulfur molybdoenzyme with broad substrate specificity.dimethyl sulfoxide reductase, a terminal electron transfer enzyme, was purified from anaerobically grown escherichia coli harboring a plasmid which codes for dimethyl sulfoxide reductase. the enzyme was purified to greater than 90% homogeneity from cell envelopes by a three-step purification procedure involving extraction with the detergent triton x-100, chromatofocusing, and deae ion-exchange chromatography. the purified enzyme was composed of three subunits with molecular weights of 82,600, 23 ...19883280546
purification and properties of the major nuclease from mitochondria of saccharomyces cerevisiae.the vast majority of nuclease activity in yeast mitochondria is due to a single polypeptide with an apparent molecular weight of 38,000. the enzyme is located in the mitochondrial inner membrane and requires non-ionic detergents for solubilization and activity. a combination of heparin-agarose and cibacron blue-agarose chromatography was employed to purify the nuclease to approximately 90% homogeneity. the purified enzyme shows multiple activities: 1) rnase activity on single-stranded, but not d ...19883286639
the yeast aminopeptidase y.a metal-dependent aminopeptidase (ec 3.4.11.-), designated apase y, has been purified to homogeneity by conventional methods. the enzyme is composed of a single polypeptide chain with molecular mass of 102 kilodaltons, estimated by sodium dodecyl sulphate - polyacrylamide gel electrophoresis, with a blocked n-terminal amino acid. it possesses neither endopeptidase nor carboxypeptidase activity and is strongly inhibited by metal-chelating agents, zn2+, and the protein inhibitor from neurospora cr ...19883042113
genetic regulation of the quinic acid utilization (qut) gene cluster in aspergillus nidulans.a large number of quinic acid non-utilizing qut mutants of aspergillus nidulans deficient in the induction of all three quinic acid specific enzymes have been analysed. one class the qutd mutants, are all recessive and are non-inducible at ph 6.5 due to inferred deficiency in a quinate ion permease. two regulatory genes have been identified. the quta gene encodes an activator protein since most quta mutants are recessive and non-inducible although a few fully dominant mutants have been found. th ...19883049934
promoter recognition by escherichia coli rna polymerase. influence of dna structure in the spacer separating the -10 and -35 regions.escherichia coli rna polymerase contacts promoter dna at two regions (the -10 and -35 regions) which are separated by a segment of spacer dna. previously we showed that base substitutions in the spacer dna can affect promoter strength both in vitro and in vivo; these results were interpreted to reflect altered structural properties of the substituted dnas. here we provide experimental support for this interpretation. the pattern of cleavage of the promoters with neurospora crassa endonuclease an ...19883050126
molecular cloning, identification and transcriptional analysis of genes involved in acetate utilization in neurospora crassa.four neurospora crassa genomic clones have been selected as hybridizing much more strongly to labelled mrna isolated from acetate-grown mycelium than to mrna from sucrose-grown mycelium. hybridization of restriction fragments with acetate-specific mrna or cdna has been used to delimit the transcribed region(s) of each clone. the transcription of all four clones is strongly induced by transfer of growing mycelium from sucrose to acetate as sole carbon source. in wild-type mycelium, mrnas correspo ...19883054423
mitotic gene conversion, reciprocal recombination and gene replacement at the bena, beta-tubulin, locus of aspergillus nidulans.we have developed a procedure for determining the rates of mitotic recombination of an interrupted duplication created by integration of transforming plasmid sequences at the bena, beta-tubulin, locus of aspergillus nidulans. transformation of a strain carrying a benomyl-resistant bena allele with plasmid aipgm4, which carries the wild-type bena allele and the pyr4 (orotidine-5'-phosphate decarboxylase) gene of neurospora crassa, creates an interrupted duplication with plasmid sequences flanked ...19883054484
sequence organization and putative regulatory elements in the 5s rrna genes of two higher plants (vigna radiata and matthiola incana).the tandemly arranged and clustered highly repeated 5s rrna genes are investigated for two plants belonging to different higher plant families: matthiola incana (brassicaceae, dilleniidae, rosidae; 3600 5s rrna genes/n) shows a homogeneous repeat size of 510 bp, whereas vigna radiata (mung bean, former phaseolus aureus, fabaceae, rosidae; approx. 4300 5s rrna genes) has a repeat size of 215 bp. the mung-bean 5s rrna coding region starts 5' with agg and ends with cct; matthiola starts with ggg an ...19883371663
primary structure of cucumber (cucumis sativus) ascorbate oxidase deduced from cdna sequence: homology with blue copper proteins and tissue-specific expression.cdna clones for ascorbate oxidase were isolated from a cdna library made from cucumber (cucumis sativus) fruit mrna. the library was screened with synthetic oligonucleotides that encode the nh2-terminal sequence of this enzyme. nucleotide sequence analysis of the cloned cdna inserts revealed a 1761-base-pair open reading frame that encoded an nh2-terminal signal peptide of 33 amino acids and a mature enzyme of 554 amino acids (mr, 62,258). the amino acid sequence deduced from nucleotide sequence ...19892919172
transformation in fungi.transformation with exogenous deoxyribonucleic acid (dna) now appears to be possible with all fungal species, or at least all that can be grown in culture. this field of research is at present dominated by saccharomyces cerevisiae and two filamentous members of the class ascomycetes, aspergillus nidulans and neurospora crassa, with substantial contributions also from fission yeast (schizosaccharomyces pombe) and another filamentous member of the class ascomycetes, podospora anserina. however, tr ...19892651864
two proteins encoded at the chla locus constitute the converting factor of escherichia coli chla1.molybdopterin (mpt) is not produced by the escherichia coli mutants chla1, chlm, or chln or by the neurospora crassa mutant nit-1. extracts of e. coli chla1 contain an activity, the converting factor, which is functionally defined by its ability to convert a low-molecular-weight precursor present in crude extracts of n. crassa nit-1 into molybdopterin in vitro. in this study, it has been shown that the converting factor consists of two associative proteins (10 and 25 kilodaltons [kda]) which can ...19892656653
acyl carrier protein is present in the mitochondria of plants and eucaryotic micro-organisms.proteins antigenically similar to the acyl carrier protein (acp) found in the mitochondria of neurospora crassa were detected by immunoblotting and radioimmunoassay techniques in mitochondria isolated from yeast, potatoes, and pea leaves. these mitochondrial proteins were similar to neurospora acp both in their electrophoretic mobility and in their unusual decrease in mobility upon reduction. authentic acp(s) show this type of change upon conversion of the acylated to the unacylated form. purifi ...19892680483
yeast cyclophilin: isolation and characterization of the protein, cdna and gene.cyclophilin (cph) has been isolated from the yeast saccharomyces cerevisiae, purified to homogeneity and partially sequenced. oligodeoxyribonucleotides deduced from this sequence were used to isolate the corresponding cdna and gene. an open reading frame coding for a 162-amino acid (aa) protein with a calculated mr of 17,392, was deduced from the nucleotide sequence. comparison between yeast and human cph shows a very high overall sequence conservation (65% aa homology). the binding of yeast cph ...19892687115
improved transformation efficiency of aspergillus niger using the homologous niad gene for nitrate reductase.aspergillus niger transformation frequencies of up to 1,176 transformants per micrograms dna were achieved using the plasmid vector psta10 containing the a. niger nitrate reductase structural gene. analysis of genomic endonuclease cleaved dna from nitrate utilising transformants by dna hybridisation, showed that most integration events are as a result of homologous recombination. the niad transformation system was used successfully for the introduction of the unselected escherichia coli fusion g ...19892791035
molecular characterization of trp1, a gene coding for tryptophan synthetase in the basidiomycete coprinus cinereus.we utilized a cloned gene (trp5) encoding tryptophan synthetase (tsase) from saccharomyces cerevisiae to identify and clone the corresponding gene (trp1) from the basidiomycete coprinus cinereus. the primary nucleotide (nt) sequence of this gene was determined and compared to sequences from other filamentous fungi, as well as to other genes coding for tsase. a transformation assay was used to demonstrate that 321 nt, which do not include caat or tataaa elements and precede the translation initia ...19892806911
inhibition by aluminum hydroxide of the voltage-dependent closure of the mitochondrial channel, vdac.micromolar quantities of aluminum have been found (dill et al. (1987) j. membrane biol. 99, 187-196) to reduce the voltage dependence of the mitochondrial outer membrane channel, vdac, from neurospora crassa. in the present study, various metallic and organic ions were tested for possible aluminum-like effect, and only the trivalent metals exhibited a similar ability to reduce the channels voltage dependence. however, trivalency alone was not sufficient because lanthanum (iii) had no effect. qua ...19892469483
pneumocystis carinii: sequence from ribosomal rna implies a close relationship with fungi.pneumocystis carinii is the etiologic agent of a lethal pneumonia which occurs in patients with the acquired immune deficiency syndrome (aids) and other immunocompromised hosts. the basic biochemical and genetic characteristics of p. carinii are poorly understood and its taxonomic classification as a protozoan is uncertain. to address the taxonomic question, a method was developed for the extraction of total rna from p. carinii. denaturing agarose gel electrophoresis showed the two ribosomal rna ...19892470612
pneumocystis carinii: taxing taxonomy.the detailed taxonomy of pneumocystis carinii has not been decided. most experts agree that it is either a fungus or a protozoan. in favor of a fungal designation are the recent reports that 16s and 18s rrna sequences of p. carinii have greater homology to saccharomyces cerevisiae and neurospora crassa than to selected protozoa. other studies show that sequences of the 18s and 26s rrna, microtubular ultrastructure, membrane fusion potential and dna content per cell resemble protozoa more than fu ...19892477272
characterization of the mitochondrial porin from drosophila melanogaster.mitochondrial porin was isolated from the fruit fly drosophila melanogaster at different developmental stages, starting from whole mitochondria. the porin from adults' mitochondria was fully characterized. the protein had a molecular mass of 31 kda as judged from sodium dodecylsulfate electrophoretograms. it was very resistive against digestion with v8 proteinase of staphylococcus aureus and a larger number of fragments were only obtained after digestion with papain. drosophila porin showed litt ...19892480813
dna sequence and secondary structures of the large subunit rrna coding regions and its two class i introns of mitochondrial dna from podospora anserina.dna sequence analysis has shown that the gene coding for the mitochondrial (mt) large subunit ribosomal rna (rrna) from podospora anserina is interrupted by two class i introns. the coding region for the large subunit rrna itself is 3715 bp and the two introns are 1544 (r1) and 2404 (r2) bp in length. secondary structure models for the large subunit rrna were constructed and compared with the equivalent structure from escherichia coli 23s rrna. the two structures were remarkably similar despite ...19892494353
genetic transformation system for the aflatoxin-producing fungus aspergillus flavus.a heterologous transformation system was developed for aspergillus flavus with efficiencies greater than 20 stable transformants per micrograms of dna. protoplasts of uracil-requiring strains of the fungus were transformed with plasmid and cosmid vectors containing the pyr-4 gene of neurospora crassa. transformants were selected for their ability to grow and sporulate on medium lacking uracil. vector dna appeared to integrate randomly into the genome of a. flavus with a tendency for multiple, ta ...19892495764
[properties of 2,5-diamino-4-oxy-6-ribosylaminopyrimidine-5'- phosphate reductase, a enzyme of the second stage of flavinogenesis in pichia guilliermondii yeasts].2,5-diamino-4-oxy-6-ribosylaminopyrimidine-5'-phosphate reductase has been isolated from cells of pichia guilliermondii and subjected to 20-fold purification by treating extracts with streptomycin sulphate, frationating proteins (nh4)2so4 at 45-75% of saturation and chromatography on blue sepharose cl-6b. the use of gel filtration through sephadex g-150 and chromatography on deae-cellulose proved to be less effective for the enzyme purification. it has been established that it is 2,5-diamino-4-o ...19892511652
a mitochondrial protein from neurospora crassa detected both on ribosomes and in membrane fractions. analysis of the gene, the message, and the protein.we have isolated clones representing at least three nuclear genes for mitochondrial ribosomal proteins from neurospora crassa by screening a lambda gt11 cdna library with an antiserum against a mixture of these proteins. the cdna and genomic dna sequence for one of these genes, mrp-3, was determined. the mrp3 protein was purified by immune-affinity chromatography, using a monoclonal antibody probe, and subjected to amino acid sequence analysis to identify the mature amino terminus and a prospect ...19892521217
nucleotide sequence of the neurospora crassa trp-3 gene encoding tryptophan synthetase and comparison of the trp-3 polypeptide with its homologs in saccharomyces cerevisiae and escherichia coli.the complete nucleotide sequence of the neurospora crassa trp-3 gene-encoding tryptophan synthetase has been determined; we present an analysis of its structure. a comparison of the deduced amino acid sequence of the trp-3 polypeptide with its homologs in saccharomyces cerevisiae (encoded by the trp5 gene) and escherichia coli (encoded by the trpa and trpb genes) shows that the a and b domains (amino acid segments homologous to the trpa and trpb polypeptides, respectively) of the n. crassa and y ...19892521855
molybdenum cofactor biosynthesis in humans. identification of two complementation groups of cofactor-deficient patients and preliminary characterization of a diffusible molybdopterin precursor.molybdenum cofactor deficiency is a devastating disease with affected patients displaying the symptoms of a combined deficiency of sulfite oxidase and xanthine dehydrogenase. because of the extreme lability of the isolated, functional molybdenum cofactor, direct cofactor replacement therapy is not feasible, and a search for stable biosynthetic intermediates was undertaken. from studies of cocultured fibroblasts from affected individuals, two complementation groups were identified. coculture of g ...19892522104
x-ray-induced specific locus mutations in the ad-3 region of two-component heterokaryons of neurospora crassa. iii. genetic fine structure analysis of the ad-3 and immediately adjacent genetic regions by means of complementation tests.genetic fine structure analysis of the ad-3 and immediately adjacent genetic regions was made by means of complementation tests on all possible pairwise combinations of 50 x-ray-induced irreparable adenine-3 mutants (designated ad-3ir). all mutants were induced in either heterokaryon 11 or heterokaryon 12 of neurospora crassa, 2-component heterokaryons heterozygous for mutants at the 3 closely linked loci ad-3a and ad-3b and nic-2 (nicotinamide-requiring) located about 5.0 map units distal to ad ...19892522164
assembly kinetics and identification of precursor proteins of complex i from neurospora crassa.complex i from neurospora crassa was fractionated using chaotropic agents and various chromatographic techniques. several subunits were isolated. polyclonal antibodies directed against the holocomplex or individual subunits were raised in rabbits, and employed to analyse the composition and assembly of this respiratory chain enzyme in vivo. n. crassa cells were pulse-labelled with radioactive amino acids. the time course of incorporation of radioactivity into complex-i polypeptides was studied b ...19892523803
a family of mitochondrial proteins involved in bioenergetics and biogenesis.the respiratory chain complexes of mitochondria consist of many different subunits, of which only a few partake directly in electron transport. the functions of the subunits that do not contain prosthetic groups are largely unknown. the cytochrome reductase complex of neurospora crassa, for examine, consists of nine different subunits, of which the peripheral membrane proteins i and ii (ref.3) that are located on the matrix side of the mitochondrial inner membrane are the largest subunits devoid ...19892524007
purification and characterisation of nad-glutamate dehydrogenase from aspergillus nidulans.nad-glutamate dehydrogenase has been purified from mycelia of a. nidulans. the enzyme comprises subunits of 110 kda. it is located in the cytosol. it is completely denatured by 1.0 m guanidine hydrochloride, and is not renatured by subsequent dilution. isophthalate is a strong competitive inhibitor and the enzyme is also inhibited by thiol reagents. the properties of the enzyme were compared to those from other fungi in terms of size, sensitivity to inhibitors, intracellular distribution and mod ...19892524418
recombination and replication of plasmid-like derivatives of a short section of the mitochondrial chromosome of neurospora crassa.the 21-kbp mitochondrial chromosome of the stp-ruv strain of neurospora crassa undergoes regional amplification yielding plasmid-like supercoiled circles varying in size from subunit length to very high multimers. a comparison of the base sequence of the five plasmids studied, with the region of the chromosome from which they were derived, indicated that the amplified chromosomal segments were determined by a recombination-excision process near or within two structurally distinctive regions. one ...19892524421
cys-3, the positive-acting sulfur regulatory gene of neurospora crassa, encodes a protein with a putative leucine zipper dna-binding element.the sulfur-regulatory circuit of neurospora crassa consists of a set of unlinked structural genes which encode sulfur-catabolic enzymes and two major regulatory genes which govern their expression. the positive-acting cys-3 regulatory gene is required to turn on the expression of the sulfur-related enzymes, whereas the other regulatory gene, scon, acts in a negative fashion to repress the synthesis of the same set of enzymes. expression of the cys-3 regulatory gene was found to be controlled by ...19892524646
molecular cloning of a neurospora crassa carotenoid biosynthetic gene (albino-3) regulated by blue light and the products of the white collar genes.the albino-3 (al-3) gene of neurospora crassa, which probably encodes the carotenoid biosynthetic enzyme geranylgeranyl pyrophosphate synthetase, was cloned. the n. crassa triple mutant al-3 qa-2 aro-9 was transformed to qa-2+ with mixtures of plasmids bearing n. crassa dna inserts, and the transformants were screened for the al-3+ phenotype. one al-3+ qa-2+ transformant (al3-1) was examined in detail and shown to contain intact vector sequences integrated into the n. crassa genome. the vector a ...19892524647
photoaffinity labelling of mitochondrial nadh: ubiquinone reductase with pethidine analogues.1. chemically reactive derivatives of pethidine analogues--novel potent inhibitors of the mitochondrial nadh: ubiquinone reductase (complex i)--were synthesized. 2. dose-response curves of these components revealed that the photoactivatable aryl azido derivative has retained most of the inhibitory activity displayed by the parent substance. after introduction of a radioactive iodine isotope into the molecule, it was used as a probe for the localization of the inhibitor binding polypeptides withi ...19892525381
transformation of neurospora crassa by an integrative transforming plasmid is not enhanced by ribosomal dna sequences.two integrative transforming plasmids of neurospora crassa that differed only by the presence of almost all of a ribosomal dna repeat unit on one plasmid were constructed. the plasmids were used to test the target concentration hypothesis which states that the transformation frequency is proportional to the number of genomic copies of a homologous sequence located on the transforming plasmid. since there are approx. 200 copies of the rdna sequences in the genome, the target concentration hypothe ...19892525404
an optimized procedure for sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of hydrophobic peptides from an integral membrane protein.a procedure for successful analysis of the hydrophobic tryptic peptides of the neurospora crassa plasma membrane h+-atpase by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page) is described. the features of this procedure that are essential for the best results include (i) treatment of the hydrophobic peptide samples with neat trifluoroacetic acid, (ii) dissolution and disaggregation of the hydrophobic peptide samples with sds at 0 degrees c, (iii) sds-page of the hydrophobic p ...19892525882
development of an in vitro transcription system for neurospora crassa mitochondrial dna and identification of transcription initiation sites.we have developed an in vitro transcription system for neurospora crassa mitochondrial dna (mtdna) and used it to identify transcription initiation sites at the 5' ends of the genes encoding the mitochondrial small and large rrna and cytochrome b (cob). the in vitro transcription start sites correspond to previously mapped 5' ends of major in vivo transcripts of these genes. sequences around the three transcription initiation sites define a 15-nucleotide consensus sequence, 5'-ttagara(t/g)g(t/g) ...19892528684
a unique low frequency raman band associated with metal binding to metallothionein.we find that the low frequency raman spectrum of zn(ii) metallothionein has a single prominent band at 138 cm-1 which is absent from the raman spectrum of the metal-free protein. this feature is also found for cd(ii) binding to both of the independent metallothionein domains and the metallothionein from neurospora crassa. tco(iii) coordination to metallothionein results in a similar raman band which is also found for the complex (ph4as)[reo(sch2ch2s)2]. by comparing these results to literature d ...19892528950
translocation arrest by reversible folding of a precursor protein imported into mitochondria. a means to quantitate translocation contact sites.passage of precursor proteins through translocation contact sites of mitochondria was investigated by studying the import of a fusion protein consisting of the nh2-terminal 167 amino acids of yeast cytochrome b2 precursor and the complete mouse dihydrofolate reductase. isolated mitochondria of neurospora crassa readily imported the fusion protein. in the presence of methotrexate import was halted and a stable intermediate spanning both mitochondrial membranes at translocation contact sites accum ...19892529262
x-ray-induced specific-locus mutations in the ad-3 region of two-component heterokaryons of neurospora crassa. iv. irreparable mutants of genotype ad-3a and ad-3b result from multilocus deletion and an unexpectedly high frequency of multiple-locus mutations.the induction of specific-locus mutations in the ad-3 region of neurospora crassa after x-irradiation was studied in a two-component heterokaryon to determine: (1) the ratio of reparable ad-3 mutants (presumed gene/point mutations, designated ad-3r) to irreparable ad-3 mutants (presumed multilocus deletions, designated ad-3ir), and (2) the induction kinetics of each class (webber and de serres, 1965). more extensive genetic tests made subsequently (de serres, 1989a) on the 832 x-ray-induced spec ...19892529438
oxidation of neurospora crassa nadp-specific glutamate dehydrogenase by activated oxygen species.the glutamine synthetase and the nadp-specific glutamate dehydrogenase activities of neurospora crassa were lost in a culture without carbon source only when in the presence of air. glutamine synthetase was previously reported to be liable to in vitro and in vivo inactivation by activated oxygen species. here we report that nadp-specific glutamate dehydrogenase was remarkably stable in the presence of activated oxygen species but was rendered susceptible to oxidative inactivation when chelated i ...19892530208
stereoselective arginine binding is a phylogenetically conserved property of group i self-splicing rnas.we have examined the reaction of gtp with rna polymerase transcripts containing the self-splicing rna precursors from the neurospora crassa cob1 intron, and from introns in the suny, nrdb and td genes of bacteriophage t4. in each case, we find a low km for gtp (between 0.8 and 11 microm), accompanied by competitive inhibition of the gtp reaction by l-arginine, as was found for the previously examined tetrahymena nuclear pre-rrna intron. trials with the 20 standard amino acids show that inhibitio ...19892531082
molecular cloning and expression in saccharomyces cerevisiae and neurospora crassa of the invertase gene from neurospora crassa.a plasmid (named pcn2) carrying a 7.6 kb bamhi dna insert was isolated from a neurospora crassa genomic library raised in the yeast vector yrp7. saccharomyces cerevisiae suco and n. crassa inv strains transformed with pnc2 were able to grow on sucrose-based media and expressed invertase activity. saccharomyces cerevisiae suco (pnc2) expressed a product which immunoreacted with antibody raised against purified invertase from wild type n. crassa, although s. cerevisiae suc+ did not. the cloned dna ...19892531138
sensitivity to cyclosporin a is mediated by cyclophilin in neurospora crassa and saccharomyces cerevisiae.cyclosporin a, a cyclic fungal undecapeptide produced by tolypocladium inflatum, is a potent immunosuppressive drug originally isolated as an antifungal antibiotic. cyclosporin a (csa) is widely used in humans to prevent rejection of transplanted organs such as kidney, heart, bone marrow and liver. the biochemical basis of csa action is not known: its primary cellular target has been suggested to be calmodulin, the prolactin receptor or cyclophilin, a csa-binding protein originally isolated from ...19892531848
regulation of the nuclear genes encoding the cytoplasmic and mitochondrial leucyl-trna synthetases of neurospora crassa.we show that the nuclear genes for the cytoplasmic and mitochondrial leucyl-trna synthetase (leurs) of neurospora crassa are distinct in their encoded proteins, codon usage, mrna levels, and regulation. the 4.2-kilobase-pair region representing the structural gene for cytoplasmic leurs and flanking regions has been sequenced. the positions of the 5' and 3' ends of mrna and of a single 62-base-pair intron have been mapped. the methionine-initiated open reading frame encoded a protein of 1,123 ami ...19892532300
bialaphos resistance as a dominant selectable marker in neurospora crassa.conidia of neurospora crassa are sensitive to the herbicide bialaphos at concentrations of 160 mg/l in westergaard's or fries' minimal media. plasmid pja4 was constructed by inserting a truncated bar gene from streptomyces hygroscopicus fused to the his-3 promoter from n. crassa into puc19. the bar gene in plasmid pja4 confers resistance to bialaphos when transformants are selected on a medium containing bialaphos. the bar gene can be used as an additional dominant selectable marker for transfor ...19892532965
evidence for three differentially regulated catalase genes in neurospora crassa: effects of oxidative stress, heat shock, and development.genetic and biochemical studies demonstrated that neurospora crassa possesses three catalases encoded by three separate structural genes. the specific activities of the three enzymes varied in response to superoxide-mediated stress, heat shock, and development. the three loci, which we designated cat-1, cat-2, and cat-3, map to the right arms of chromosomes iii, vii, and iii, respectively. the cat-1-encoded enzyme (designated cat-1; estimated molecular weight, 315,000; pi 5.2) was the predominan ...19892540152
cytochrome oxidase subunit v gene of neurospora crassa: dna sequences, chromosomal mapping, and evidence that the cya-4 locus specifies the structural gene for subunit v.the sequences of cdna and genomic dna clones for neurospora cytochrome oxidase subunit v show that the protein is synthesized as a 171-amino-acid precursor containing a 27-amino-acid n-terminal extension. the subunit v protein sequence is 34% identical to that of saccharomyces cerevisiae subunit v; these proteins, as well as the corresponding bovine subunit, subunit iv, contain a single hydrophobic domain which most likely spans the inner mitochondrial membrane. the neurospora crassa subunit v g ...19892540423
amino acid sequence of the alpha and beta subunits of methanosarcina barkeri atpase deduced from cloned genes. similarity to subunits of eukaryotic vacuolar and f0f1-atpases.the atpa and atpb genes coding for the alpha and beta subunits, respectively, of membrane atpase were cloned from a methanogen methanosarcina barkeri, and the amino acid sequences of the two subunits were deduced from the nucleotide sequences. the methanogenic alpha (578 amino acid residues) and beta (459 amino acid residues) subunits were highly homologous to the large and small subunits, respectively, of vacuolar h+-atpases; 52% of the residues of the methanogenic alpha subunit were identical ...19892544575
nucleotide sequence and regulation of expression of the aspergillus nidulans gdha gene encoding nadp dependent glutamate dehydrogenase.the nucleotide sequence of the aspergillus nidulans gdha gene encoding nadp linked glutamate dehydrogenase has been determined and northern blot analysis used to study the regulation of expression of this gene. the gdha gene is 1485 nucleotides long and, by comparison with the corresponding neurospora crassa am gene, has two putative introns of 53 nucleotides and a protein encoding region of 1380 nucleotides that codes for an inferred protein of 49.63 kda which shows regions of homology with glu ...19892550758
reconstitution of a light-stimulated adenylate cyclase from retina and neurospora crassa preparations. characterization of the heterologous systems using normal and degenerative retinas.adenylate cyclase catalytic subunits from neurospora crassa membranes may interact with regulatory factors from membranes of bovine retinal rod outer segments (pretreated with n-ethylmaleimide), reconstituting a heterologous system which, in the presence of light, is catalytically active in assay mixtures containing mgatp. maximal activation was observed at 550 nm. transducin-depleted retinal membranes were not capable of reconstituting the heterologous light-stimulated adenylate cyclase system. ...19892553402
[identification of human porins. ii. characterization and primary structure of a 31-lda porin from human b lymphocytes (porin 31hl)].we characterize and describe for the first time the primary structure of a human porin with the molecular mass of 31 kda derived from the plasmalemm of b-lymphocytes (porin 31hl). porin 31hl is shown to be a basic, channel forming membrane protein. the protein chain is composed of 282 amino acids with a relative molecular mass of 30641 da without derivatisation. it is not a glycoprotein. the n-terminus is acetylated. altogether the amino-acid sequence shows 56% hydrophilic or charged amino acids ...19892559745
cloning and analysis of the neurospora crassa gene for cytochrome c heme lyase.the cyt-2-1 mutant of neurospora crassa is deficient in cytochromes aa3 and c and in cytochrome c heme lyase activity (mitchell, m.b., mitchell, h.k., and tissieres, a. (1953) proc. natl. acad. sci. u.s.a. 39, 606-613; nargang, f.e., drygas, m.e., kwong, p.l., nicholson, d.w., and neupert, w. (1988) j. biol. chem. 263, 9388-9394). by rescue of the slow growth character of the cyt-2-1 mutant, we have cloned the cyt-2+ gene from a n. crassa genomic library using sib selection. analysis of the dna ...19892572587
transformation by integration in podospora anserina. iii. replacement of a chromosome segment by a two-step process.we have developed in podospora anserina a two-step procedure for dna sequence replacement through transformation which might be applicable to other filamentous fungi. targeting of transforming dnas to their homologous locus is achieved provided a cosmid vector is used. southern blot analysis of genomic dnas from a set of transformants is presented. the data confirm that cosmids integrate into the chromosome through mostly homologous recombination which leads to a duplicated sequence separated by ...19892575706
a nuclear mutant of neurospora crassa lacking subunit 1 of cytochrome c oxidase. 1989210181
immunochemical analysis shows that an atp/adp-translocator is associated with the inner-envelope membranes of amyloplasts from acer pseudoplatanus l.pure preparations of intact amyloplasts and chloroplasts, free from mitochondrial contamination, were isolated from cultured cells of the white-wild and green-mutant lines of sycamore (acer pseudoplatanus l.), respectively. a specific rabbit antiserum against yeast mitochondrial cytochrome c(1) only cross-reacted with mitochondrial membranes from the white-wild sycamore cells. the outer and inner envelope-membranes of the two plastid-types were isolated and subsequently analyzed by sodium dodecy ...198916666656
preparation of neurospora crassa chromosomes from a cell wall-less strain. 19892532324
secretion of an mr 60000 protein by benomyl-treated cells of neurospora crassa.in the presence of the microtubule inhibitor benomyl at micron concentrations, cells of neurospora crassa wild type strain st. lawrence 74a were found to secrete high amounts of an mr 60 000 protein into the culture medium (about 35 micrograms/ml after a 12 h treatment). the secretion also occurred after treatment with the other antitubulin drugs carbendazim (mbc), nocodazole, thiabendazole, and griseofulvin. this secretion is apparently induced by the specific action of benomyl on n. crassa bet ...19892534075
nuclear gene for mitochondrial leucyl-trna synthetase of neurospora crassa: isolation, sequence, chromosomal mapping, and evidence that the leu-5 locus specifies structural information.we have isolated and characterized the nuclear gene for the mitochondrial leucyl-trna synthetase (leurs) of neurospora crassa and have established that a defect in this structural gene is responsible for the leu-5 phenotype. we have purified mitochondrial leurs protein, determined its n-terminal sequence, and used this sequence information to identify and isolate a full-length genomic dna clone. the 3.7-kilobase-pair region representing the structural gene and flanking regions has been sequenced ...19892574823
isolation and characterization of a laccase-derepressed mutant of neurospora crassa.laccase from the ascomycete neurospora crassa is an inducible secretory enzyme. production of this enzyme is repressed in vegetative cultures but can be induced by treatment with low concentrations of cycloheximide. isolation and characterization of a derepressed mutant, the lah-1 mutant, that is capable of producing laccase in vegetative cultures without induction by cycloheximide are described. the lah-1 mutation is mapped between nit-2 and leu-3 on linkage group i, and it behaved as a recessi ...19892553675
classical and molecular genetic analyses of his-3 mutants of neurospora crassa. ii. southern blot analyses and molecular mechanisms of mutagenicity.previous studies (overton et al., mutation res., 1989) on specific revertibility of 81 his-3 mutants have shown a correlation between complementation pattern and presumed genetic alteration similar to that shown by ad-3b mutants. in the present study, restriction enzyme analyses were used to further characterize the genetic alterations in individual his-3 mutants. the restriction fragment banding patterns of the majority of mutants were identical with that shown by wild-type 74-or23-1a and were ...19892530448
isolation and characterization of the tyrosinase gene from neurospora crassa.a precursor form of neurospora crassa tyrosinase has been identified by western transfer from crude protein extracts and by immunoprecipitation of in vitro translated tyrosinase mrna. the molecular weight of protyrosinase (75,000) exceeds that of mature tyrosinase (46,000) by about 50%. in order to deduce the primary structure and the nature of the extension, the tyrosinase gene was cloned. poly(a) rna isolated from tyrosinase-induced cultures of n. crassa was used as a template for cdna synthes ...19892529259
evidence for an essential histidine residue in the neurospora crassa plasma membrane h+-atpase.the neurospora crassa plasma membrane h+-atpase is rapidly inactivated in the presence of diethyl pyrocarbonate (dep). the reaction is pseudo-first-order showing time- and concentration-dependent inactivation with a second-order rate constant of 385-420 m-1.min-1 at ph 6.9 and 25 degrees c. the difference spectrum of the native and modified enzyme has a maximum near 240 nm, characteristic of n-carbethoxyhistidine. no change in the absorbance of the inhibited atpase at 278 nm or in the number of ...19892528992
an ethidium bromide induced mutant of neurospora crassa defective in mitochondrial dna.slow growing mutants of neurospora crassa were obtained by ethidium bromide treatment of the wild type strain. a particular mutant er-3 showed stopper phenotype accompanied by deficient cytochrome spectra. the mutant showed an altered restriction pattern of the mtdna which indicated a deletion of 25,000 bp. the phenotype of the ethidium bromide induced mutant er-3 seem to be related to the loss of several essential genes due to a deletion in its mtdna.19892534062
molecular and classical genetic analyses of his-3 mutants of neurospora crassa. i. tests for allelic complementation and specific revertibility.a collection of 81 his-3 mutants of neurospora crassa was analyzed in assays for allelic complementation and specific revertibility. in these studies, the linearity of the complementation map of the his-3 cistron (webber, 1965) was confirmed and mutants were classified as complementing with non-polarized or polarized complementation patterns, or non-complementing. in the assays for spontaneous or induced revertibility, 89% (71/80) of the mutants reverted either spontaneously or after treatment w ...19892529437
a cycloheximide-inducible gene of neurospora crassa belongs to the cytochrome p-450 superfamily. 19892529480
the vacuolar atpase of neurospora crassa contains an f1-like structure.we have explored the structure and subunit composition of the vacuolar atpase of neurospora crassa by investigating the effects of nitrate. inhibition of enzyme activity by nitrate was correlated with dissociation of a complex of peripheral polypeptides from the integral membrane part of the enzyme. surprisingly, this nitrate-induced release of subunits occurred only when nucleotides such as adp, atp, or itp were present. atpase inhibitors that have been proposed to act at the active site preven ...19892527854
calcium activates an electrogenic proton pump in neurospora plasma membrane.calcium ionophoresis into coenocytic cells of neurospora crassa activates the plasma membrane proton pump as measured by current-voltage analysis. this is direct evidence that intracellular calcium regulates the activity of a key transport enzyme found in higher plants and fungi.198916666998
isolation of a gene that down-regulates nitrate assimilation and influences another regulatory gene in the same system.glutamine is the preferred source of nitrogen of neurospora crassa. in its presence and that of the gene product of ms5 (nmr-1), the fungus represses the assimilation of less preferred forms of nitrogen, such as nitrate. in the absence of glutamine and the presence of the product of gene nit-2, less preferred forms of nitrogen are assimilated as long as a specific pathway for their assimilation is induced. we report here the isolation, from a cosmid bank, of a gene that complements ms5 and can a ...19892528690
molecular cloning and regulatory analysis of the arylsulfatase structural gene of neurospora crassa.the ars-1+ gene of neurospora crassa encodes the enzyme arylsulfatase. ars-1+ is in a group of highly regulated sulfur-related structural genes that are expressed under conditions of sulfur limitation and are under coordinate control of the cys-3+ and scon+ regulatory genes. the ars-1+ gene was cloned by chromosome walking from the qa gene cluster, using a lambda library. cotransformation of an n. crassa ars-1 mutant with the isolated lambda clones and the benomyl resistance gene, followed by as ...19892528685
epistasis, photoreactivation and mutagen sensitivity of dna repair mutants upr-1 and mus-26 in neurospora crassa.double mutants were constructed combining mus-26, formerly designated uvs-(sa3b), with other uv-sensitive mutants. tests of sensitivity of these double mutants to uv and to chemical mutagens revealed that mus-26 and upr-1 belong to the same epistatic group. the uv dose-response curve of mus-26 showed a characteristic plateau in the range of 100-200 j/m2. the same characteristic was also shown in the dose-response curves of upr-1 and the double mutant, upr-1 mus-26. photoreactivation of uv damage ...19892528064
mutations in nuclear gene cyt-4 of neurospora crassa result in pleiotropic defects in processing and splicing of mitochondrial rnas.the nuclear cyt-4 mutants of neurospora crassa have been shown previously to be defective in splicing the group i intron in the mitochondrial large rrna gene and in 3' end synthesis of the mitochondrial large rrna. here, northern hybridization experiments show that the cyt-4-1 mutant has alterations in a number of mitochondrial rna processing pathways, including those for cob, coi, coii and atpase 6 mrnas, as well as mitochondrial trnas. defects in these pathways include inhibition of 5' and 3' ...19892478417
ubiquitin expression in neurospora crassa: cloning and sequencing of a polyubiquitin gene.we have cloned and sequenced a polyubiquitin gene from neurospora crassa that is organized in a four repeat-tandem array. the first repeat contains a small intron and the last is fused to an extra glutamine codon. in northern blots, two rna species of 1.3 kb and 0.7 kb hybridize to the isolated clone. the larger ubiquitin (ubi) transcript accumulates after partial inhibition of protein synthesis with cycloheximide, and the smaller one preferentially accumulates in conidia after germination. unex ...19892549509
premeiotic change of nucleolus organizer size in neurospora.we have investigated the heritability of nucleolus organizer region (nor) size in neurospora crassa. by pulsed-field gel electrophoresis, we followed in genetic crosses the size of the normal or "terminal" nors and the size of a small interstitial nor. tetrad analysis revealed that changes in nor size occur frequently in the sexual phase. moreover, most size changes occurred in the period between fertilization and meiosis, although some changes occurred during and after meiosis. unexpectedly, in ...19892527181
inositol trisphosphate induces calcium release from neurospora crassa vacuoles.inositol 1,4,5-trisphosphate is known to release calcium ions from intracellular stores thought to be parts of endoplasmic reticulum in animal cells. in neurospora crassa, however, inositol 1,4,5-trisphosphate acts on vacuoles stimulating a calcium efflux with a km of 5.28 microm. the calcium release is inhibited effectively by dantrolene. these results were obtained by applying two independent methods, measuring calcium binding to fura-2 and loading vacuoles with 45ca.19892527035
deoxyribonucleoside triphosphate pools in mutagen sensitive mutants of neurospora crassa.deoxyribonucleoside triphosphate (dntp) levels were measured in wild type neurospora and nine mutagen-sensitive mutants, at nine different genes. eight of these mutants are sensitive to hydroxyurea and histidine and show chromosomal instability, a phenotype which could result from altered levels of dntps. two patterns were seen. five of the mutants had altered ratios of dntps, with relatively high levels of datp and dgtp and low levels of dctp, but changes in the dttp/dctp ratio did not correlat ...19892527032
studies on the active site of the neurospora crassa plasma membrane h+-atpase with periodate-oxidized nucleotides.the neurospora crassa plasma membrane h+-atpase is inactivated by the periodate-oxidized nucleotides, oatp, oadp, and oamp, with oamp the most effective. inhibition of the atpase is essentially irreversible, because sephadex g-50 column chromatography of the oamp-treated atpase does not result in a reversal of the inhibition. inhibition of the atpase by oamp is protected against by the h+-atpase substrate atp, the product adp, and the competitive inhibitors tnp (2',3'-o-(2,4,6-trinitrocyclohexad ...19892545685
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