| liver regeneration in the presence of high protein and organ-containing diets. | rats, mostly young adult males, were partially hepatectomized and administered a variety of plant, yeast and animal proteins as well as raw and cooked fresh pig organs and blood, fetal pig carcass and organs, lean beef and human term placenta over a period of 10 days. each agent at 25% protein or in terms of 25--30% dry solids, was introduced into an aqueous mixture supplemented with salts, vitamins, corn oil and glucose. except for a few discrepancies, liver regeneration was stimulated by most ... | 1980 | 7216124 |
| [effect of dl-alpha-tocopherol on incorporation of selenium in "selenium-indicating" organs and on glutathione peroxidase activity in rat and rabbit erythrocytes following application of therapeutic doses of sodium selenite]. | an explanation of the functions of both vitamin e and selenium in metabolism and an account of the correlations between them is followed by reference to the results obtained by the authors of this paper from studies into the effects of dl-alpha-tocopherol on selenium levels in the m. longissimus dorsi, blood, and liver as well as on the activity of glutathione-peroxidase (ec 1.11.1.9) in erythrocytes of rabbit and rat, following application of therapeutic doses of selenium (0.5 mg/kg live weight ... | 1981 | 7224795 |
| [quaternary structure of transketolase from rat liver]. | the quaternary structure of immobilized rat liver transketolase was studied. it was shown that the individual subunits of the enzyme are active in their specific activity do not differ from the dimeric form of the enzyme. the quaternary structure stabilizes the coenzyme binding to the protein; thiamine pyrophosphate is split off from the choloenzyme only upon destruction of the quaternary structure. the hybrid dimers formed by the subunits of transketolase from rat liver and baker's yeast were o ... | 1981 | 7248378 |
| [topical anti-inflammatory activity of dexamethasone 17-valerate (author's transl)]. | the anti-inflammatory activity of dexamethasone 17-valerate ointment (dv-17, 0.12%) was investigated by topical application in mice and rats, and the effects compared with those of dexamethasone (dx, 0.12%), betamethasone 17-valerate (bv-17, 0.12%), beclomethasone 17,21-dipropionate (be, 0.025%) and hydrocortisone 17-butyrate (hc, 0.1%) which were prepared with the same ointment base. dv-17 inhibited markedly the superficial inflammation such as increased vascular permeability induced by intrade ... | 1981 | 7262708 |
| flow cytometric analysis of cellular endogenous fluorescence simultaneously with emission from exogenous fluorochromes, light scatter and absorption. | a cytofluorimeter capable of simultaneous 4-parameter analysis (i.e., endogenous fluorescence (nad(p)h), exogenous fluorescent dyes, absorption and small angle scatter) is described. analyses have been performed on isolated rat liver cells, white blood cells, bone marrow, thymus cells and yeast under different metabolic states. this allows correlations between cell function and concentration of cell substances, size, refractive indices, etc. kinetic measurements are also possible. | 1981 | 7273975 |
| salicylic acid stimulation of palmitic acid oxidation by rat skeletal muscle mitochondria. | the effects of salicylic acid on palmitic acid oxidation were studied using rat skeletal muscle mitochondria. salicylic acid, in concentrations that exerted no effect on mitochondrial coupling (0.1 mm), significantly stimulated mitochondrial palmitic acid oxidation, with maximal stimulation occurring at subsaturating concentrations of substrate. in the same preparation, salicylate had no effect on the oxidation of palmitoylcarnitine or palmitoyl-coa. salicylate appears to augment the initial ste ... | 1981 | 7295759 |
| biological activity of cannabichromene, its homologs and isomers. | cannabichromene (cbc) is one of four major cannabinoids in cannabis sativa l. and is the second most abundant cannabinoid in drug-type cannabis. cannabichromene and some of its homologs, analogs, and isomers were evaluated for antiinflammatory, antibacterial, and antifungal activity. antiinflammatory activity was evaluated by the carrageenan-induced rat paw edema and the erythrocyte membrane stabilization method. in both tests, cbc was superior to phenylbutazone. antibacterial activity of cbc an ... | 1981 | 7298870 |
| effects of dietary proteins from a variety of sources on plasma lipids and lipoproteins of rats. | five experiments were conducted to study the effect of various protein sources on fasting blood lipids and lipoproteins in the rat. plasma levels of total cholesterol, high density lipoprotein (hdl)-cholesterol and total triglyceride, as well as weight gain, food intake protein efficiency ratio and net protein utilization were measured over 28-day test periods with male sprague-dawley rats. the purified proteins studied included casein, egg albumin, lactalbumin, soy and alfalfa. crude proteins s ... | 1980 | 7365542 |
| occurrence of globulin-like migrating blood albumins, or glimbal, in pathological rat and human sera. | the presence in the serum of albumins having a globulin-like electrophoretic mobility (globulin-like migrating blood albumins or glimbal) has been determined by immunoelectrophoresis in rat and human sera. glimbal have been detected occasionally (14%) in rat sera during the acute inflammation induced by yeast injection. glimbal were, on the other hand, present in pathological human sera from patients with rheumatoid arthritis (50%), systemic lupus erythematosus (69%), and liver disease (17%). th ... | 1980 | 7388676 |
| spectral characterization of cytochrome p-450 of a strain of candida tropicalis grown on tetradecane. | several properties of the cytochrome p-450 induced in the yeast candida tropicalis by growth on tetradecane have been studied by differential visible spectroscopy on microsomes. the spectral changes typical of this cytochrome have been obtained by subtraction of an unspecific spectral change, possibly due to the presence of other hemoproteins in microsomes, from the experimental difference spectra. like the previously described cytochromes p-450 from yeast and mammalian liver, c. tropicalis cyto ... | 1980 | 7408870 |
| dietary selenium and age-related susceptibility of rat erythrocytes to oxidative damage. | the effects of age and dietary selenium on cellular susceptibility to oxidative stress were studied in rat erythrocytes. young (26 or 40 days) and mature adult (11 or 15 months) male rats were fed a torula yeast-based low selenium and low vitamin e diet supplemented with either 0, 1.0 to 2.0 ppm selenium (as sodium selenite) for 5 weeks. the rates of spontaneous hemolysis amd methemoglobin formation and levels of glutathione (gsh), glucose-6-phosphate (g6p) dehydrogenase, but not of gsh peroxida ... | 1980 | 7441374 |
| inhibition of neutral cholesteryl ester hydrolase by the glycolytic enzyme enolase. is this a secondary function of enolase? | there is an accumulation of the glycolytic enzyme enolase and of cholesteryl esters in macrophages that have been converted into "foam" cells. in this study, we questioned whether enolase could be involved in this accumulation of cholesteryl esters by inhibiting the activity of neutral cholesteryl ester hydrolases. enolase from both yeast and rabbit muscle were incubated with three different cholesteryl ester hydrolases and were shown to inhibit the hydrolysis of cholesteryl esters. inhibition w ... | 1995 | 7475993 |
| cloning of the cdna for the human atp synthase oscp subunit (atp5o) by exon trapping and mapping to chromosome 21q22.1-q22.2. | exon trapping was used to clone portions of potential genes from human chromosome 21. one trapped sequence showed striking homology with the bovine and rat atp synthase oscp (oligomycin sensitivity conferring protein) subunit. we subsequently cloned the full-length human atp synthase oscp cdna (gdb/hgmw approved name atp50) from infant brain and muscle libraries and determined its nucleotide and deduced amino acid sequence (embl/genbank accession no. x83218). the encoded polypeptide contains 213 ... | 1995 | 7490082 |
| positional cloning of the nude locus: genetic, physical, and transcription maps of the region and mutations in the mouse and rat. | mutations in the nude locus in mice and rats produce the pleiotropic phenotype of hairlessness and athymia, resulting in severely compromised immune system. to identify the causative gene, we utilized modern tools and techniques of positional cloning. specifically, spanning the region in which the nude locus resides, we constructed a genetic map of polymorphic markers, a physical map of yeast artificial chromosomes and bacteriophage p1 clones, and a transcription map of genes obtained by direct ... | 1995 | 7490093 |
| sequential coupling between copii and copi vesicle coats in endoplasmic reticulum to golgi transport. | copi and copii are vesicle coat complexes whose assembly is regulated by the arf1 and sar1 gtpases, respectively. we show that copi and copii coat complexes are recruited separately and independently to er (copii), pre-golgi (copi, copii), and golgi (copi) membranes of mammalian cells. to address their individual roles in er to golgi transport, we used stage specific in vitro transport assays to synchronize movement of cargo to and from pre-golgi intermediates, and gdp- and gtp-restricted forms ... | 1995 | 7490291 |
| role of acidic residues in the interaction of nadph-cytochrome p450 oxidoreductase with cytochrome p450 and cytochrome c. | site-directed mutagenesis of the acidic clusters 207asp-asp-asp209 and 213glu-glu-asp215 of nadph-cytochrome p450 oxidoreductase demonstrates that both cytochrome c and cytochrome p450 interact with this region; however, the sites and mechanisms of interaction of the two substrates are clearly distinct. substitutions in the first acidic cluster did not affect cytochrome c or ferricyanide reductase activity, but substitution of asparagine for aspartate at position 208 reduced cytochrome p450-depe ... | 1995 | 7499204 |
| cloning and functional analysis of the ndk1 gene encoding nucleoside-diphosphate kinase in schizosaccharomyces pombe. | we cloned the ndk1 gene encoding a subunit of nucleoside-diphosphate kinase (ndk) from schizosaccharomyces pombe, by using polymerase chain reaction. the deduced ndk1 gene product has 151 amino acid residues and is approximately 60% identical with both saccharomyces cerevisiae and mammalian ndks. the gene product exhibited ndk activity and cross-reacted with antibodies raised against rat ndk. disruption of ndk1 greatly reduced the cellular ndk activity but caused no obvious phenotype in cell gro ... | 1995 | 7499258 |
| cloning of a novel family of mammalian gtp-binding proteins (raga, ragbs, ragb1) with remote similarity to the ras-related gtpases. | cdna clones of two novel ras-related gtp-binding proteins (raga and ragb) were isolated from rat and human cdna libraries. their deduced amino acid sequences comprise four of the six known conserved gtp-binding motifs (pm1, -2, -3, g1), the remaining two (g2, g3) being strikingly different from those of the ras family, and an unusually large c-terminal domain (100 amino acids) presumably unrelated to gtp binding. raga and ragb differ by seven conservative amino acid substitutions (98% identity), ... | 1995 | 7499430 |
| gapiii, a new brain-enriched member of the gtpase-activating protein family. | ras gtpase-activating proteins (gaps) are negative regulators of ras, which controls proliferation and differentiation in many cells. ras gaps have been found in a variety of species from yeast to mammals. we describe here a newly identified mammalian gap, gapiii, which was obtained by differential screening of a rat oligodendrocyte cdna library. gapiii putatively encodes a 834 amino acid protein with a predicted molecular weight of 96 kda, which contains a consensus gap-related domain (grd). th ... | 1995 | 7500386 |
| use of a yeast expression system for the isolation and analysis of drug-resistant mutants of a mammalian phosphodiesterase. | saccharomyces cerevisiae strain pp5 has a phosphodiesterase (pde) deficiency that results in heat-shock sensitivity due to the intracellular accumulation of camp. this strain also carries the cam mutation, which confers permeability to camp and, as shown here, to other compounds. expression of rat type iv pde in these cells caused them to revert to heat-shock resistance. treatment of the transformed pp5 cells with rolipram, an antidepressant in humans and a potent inhibitor of type iv pdes, rein ... | 1993 | 7505450 |
| antipyretic and platelet antiaggregating effects of nimesulide. | nimesulide strongly inhibited ex vivo platelet aggregation in guinea-pigs after both single and repeated (once daily for 5 days) oral dosing, irrespective of the aggregating agent used (adenosine diphosphate, arachidonic acid or collagen). its potency was consistently greater than that shown by either ticlopidine or acetylsalicylic acid. in both oral and rectal administration, nimesulide proved to be more active and longer lasting than paracetamol in inhibiting fever induced in rats injected sub ... | 1993 | 7506194 |
| immunogenicity of polysaccharides conjugated to peptides containing t- and b-cell epitopes. | to develop a general model of polysaccharide-peptide vaccine, we have investigated the efficiency of linear peptides derived from protein sr, and adhesin of the i/ii protein antigen family of oral streptococci, to act as carriers for two t cell-independent polysaccharides: serogroup f polysaccharide from streptococcus mutans omz 175 (poly f) and saccharomyces cerevisiae mannan. peptide 3 (yekeptpptrtpdq) and peptide 6 (tpedptdptdpqdpss), accessible on the native sr protein as demonstrated by the ... | 1994 | 7509317 |
| the complete amino acid sequence of subunit d of rat liver mitochondrial h(+)-atp synthase. | subunit d of h(+)-atp synthase from rat liver mitochondria was isolated from the purified enzyme by reverse-phase high performance liquid chromatography. the partial amino acid sequence of the subunit was determined by automated edman degradation of the peptide fragments. the nucleotide sequence of subunit d of rat liver h(+)-atp synthase was determined from a recombinant cdna clone isolated by screening a rat hepatoma cell line h4tg cdna library with a probe dna. the sequence was composed of 58 ... | 1993 | 7509337 |
| dna sequences encoding enolase are remarkably conserved from yeast to mammals. | enolase (2-phospho-d-glycerate hydrolase, ec 4.2.1.11), particularly isoform neuron-specific enolase (nse), is primarily localized in neurons and neuroendocrine cells and is a cancer diagnostic marker for brain tumors. homology of enolase-coding dna sequences from human, dog, cow, rat, mouse, rabbit, chicken, and yeast cells was investigated using hybridization techniques, percent sequence divergence, and amino acid analysis. because enolase is a significant enzyme of the glycolytic pathway, eno ... | 1994 | 7520111 |
| reversible and irreversible effects of basic peptides on the mitochondrial cationic channel. | we have previously shown that a 13-residue basic peptide, derived from the presequence of a mitochondrial precursor, blocked the cationic channel of the outer mitochondrial membrane. the properties of the blockade suggested that the peptide could go through the pore in the presence of a sufficient driving force. in an attempt to evaluate more precisely the relevance of such an interpretation, we have examined the effect on the same channel of basic peptides from 16 to 34 residues, most of which ... | 1994 | 7521225 |
| the glucocorticoid receptor functions at multiple steps during transcription initiation by rna polymerase ii. | we have used a panel of monoclonal antibodies and a cell-free transcription assay to study the function of the tau 1 transactivation domain of the human glucocorticoid receptor. three antibodies (monoclonal antibodies 250, 275, and 286) specifically inhibited tau 1-dependent transcription, but had little or no effect on either basal transcription or the activity of an unrelated yeast transcription factor. this inhibition was not due to interference of dna binding activity, as all three antibodie ... | 1994 | 7523389 |
| phosphorylation of tau protein by casein kinase-1 converts it to an abnormal alzheimer-like state. | the microtubule-associated protein tau is abnormally hyperphosphorylated in alzheimer's disease. both proline-dependent protein kinases (pdpks) and non-pdpks are involved in this hyperphosphorylation of tau. several pdpks can phosphorylate tau in vitro and induce alzheimer-like epitopes to many phosphorylation-dependent antibodies. a similar induction has not been reported with non-pdpks. in this study we have evaluated six non-pdpks [cyclic amp-dependent (a-kinase), calcium/phospholipid-depende ... | 1995 | 7532213 |
| interaction cloning of rabin3, a novel protein that associates with the ras-like gtpase rab3a. | rab3a is a small, ras-like gtpase expressed in neuroendocrine cells, in which it is associated with secretory vesicle membranes and regulates exocytosis. using the yeast two-hybrid system, we have identified a rat brain cdna encoding a novel 50-kda protein, which we have named rabin3, that interacts with rab3a and rab3d but not with other small gtpases (rab3c, rab2, ran, or ras). several independent point mutations in the effector domain of rab3a (f51l, v55e, and g56d) which do not alter nucleot ... | 1995 | 7532276 |
| kif2 is a new microtubule-based anterograde motor that transports membranous organelles distinct from those carried by kinesin heavy chain or kif3a/b. | kinesin is known as a representative cytoskeletal motor protein that is engaged in cell division and axonal transport. in addition to the mutant assay, recent advances using the pcr cloning technique have elucidated the existence of many kinds of kinesin-related proteins in yeast, drosophila, and mice. we previously cloned five different members of kinesin superfamily proteins (kifs) in mouse brain (aizawa, h., y. sekine, r. takemura, z. zhang, m. nangaku, and n. hirokawa. 1992. j. cell biol. 11 ... | 1995 | 7535303 |
| identification of heterogeneous ribonucleoprotein a1 as a novel substrate for protein kinase c zeta. | the zeta isoform of protein kinase c (zeta pkc) has been shown to be an important step in mitogenic signal transduction. using a yeast interaction screen to search for potential novel substrates of zeta pkc, we identified the heterogeneous ribonucleoprotein a1 (hnrnpa1). this protein specifically interacts with the catalytic domain of zeta pkc but not with its regulatory region or with the full-length protein, or with a kinase-defective mutant of the zeta pkc catalytic domain. in addition, no in ... | 1995 | 7541049 |
| evidence that epithelial glycoprotein 330/megalin mediates uptake of polybasic drugs. | glycoprotein 330 (gp330) is an endocytic receptor expressed in the renal proximal tubules and some other absorptive epithelia, e.g., in the inner ear. the present study shows that the antifibrinolytic polypeptide, aprotinin, and the nephro- and ototoxic antibiotics, aminoglycosides, and polymyxin b compete for binding of 125i-urokinase-plasminogen activator inhibitor type-1 complexes to purified rabbit gp330. half maximal inhibition was measured at 4 microm for aprotinin, 50 microm for gentamici ... | 1995 | 7544804 |
| a provisional transcript map of the spinal muscular atrophy (sma) critical region. | yacs from the region containing the spinal muscular atrophy (sma) locus at 5q12 have been used as probes in a direct screening of cdna libraries to isolate 8 cdnas, mapped to different yac fragments. three clones showed complete identity to the genes for cyclin b1 (ccnb1), the p44 subunit of the transcription factor btf2 (btf2p44), and cofilin (cfl). two clones showed partial identity to the beta-glucuronidase gene (glcb) and a rat integral membrane glycoprotein gene (rninmegla). cfl turned out ... | 1995 | 7552146 |
| secretion of biologically active recombinant fibrinogen by yeast. | fibrinogen (340 kda) is a plasma protein that plays an important role in the final stages of blood clotting. human fibrinogen is a dimer with each half-molecule composed of three different polypeptides (a alpha, 67 kda; b beta, 57 kda; gamma, 47 kda). to understand the mechanism of fibrinogen chain assembly and secretion and to obtain a system capable of producing substantial amounts of fibrinogen for structure-function studies, we developed a recombinant system capable of secreting fibrinogen. ... | 1995 | 7559549 |
| assembly of voltage-gated potassium channels. conserved hydrophilic motifs determine subfamily-specific interactions between the alpha-subunits. | voltage-gated potassium (k+) channels are assembled by four identical or homologous alpha-subunits to form a tetrameric complex with a central conduction pore for potassium ions. most of the cloned genes for the alpha-subunits are classified into four subfamilies: kv1 (shaker), kv2 (shab), kv3 (shaw), and kv4 (shal). subfamily-specific assembly of heteromeric k+ channel complexes has been observed in vitro and in vivo, which contributes to the diversity of k+ currents. however, the molecular cod ... | 1995 | 7559593 |
| a proline-rich sequence unique to mek1 and mek2 is required for raf binding and regulates mek function. | mammalian mek1 and mek2 contain a proline-rich (pr) sequence that is absent both from the yeast homologs ste7 and byr1 and from a recently cloned activator of the jnk/stress-activated protein kinases, sek1/mkk4. since this pr sequence occurs in meks that are regulated by raf family enzymes but is missing from meks and seks activated independently of raf, we sought to investigate the role of this sequence in mek1 and mek2 regulation and function. deletion of the pr sequence from mek1 blocked the ... | 1995 | 7565670 |
| a role for phosphatidylinositol transfer protein in secretory vesicle formation. | vesicular traffic in eukaryotic cells is characterized by two steps of membrane rearrangement: the formation of vesicles from donor membranes and their fusion with acceptor membranes. with respect to vesicle formation, several of the cytosolic proteins implicated in budding and fission have been identified. a feature common to all these proteins is that their targets, when known, are other proteins rather than lipids. here we report, using a previously established cell-free system derived from a ... | 1995 | 7566155 |
| effects of solutes on optical properties of biological materials: models, cells, and tissues. | perturbations of scattering background for absorbance measurements by photon diffusion techniques complicate algorithms used for determining the concentration of blood and the saturation of hemoglobin in tissues. in order to better define these perturbations, we have undertaken a study of the effect of solutes, some of physiological importance, upon the scattering of three types of model systems: a lipid vessel suspension (intralipid), a cell suspension (baker's yeast), and a tissue (perfused li ... | 1995 | 7573957 |
| marked effects of alcohols and imidazoles on the cumyl hydroperoxide reaction with the wild-type cytochrome p450 1a2. | cytochrome p450 catalyzes monooxidation reactions of many organic compounds in the presence of hydroperoxides even in the absence of electron-transfer proteins and molecular oxygen. to understand the mechanism of the hydroperoxide-induced cytochrome p450 reactions, we investigated effects of ligands such as alcohols and imidazoles and 7-ethoxycoumarin, a substrate of cytochrome p450 1a2 (p450 1a2), on the cumyl hydroperoxide (chp) o-o cleavage reaction with wild-type p450 1a2. formation rates of ... | 1995 | 7574687 |
| the oncogene qin codes for a transcriptional repressor. | the retroviral oncogene qin codes for a protein that belongs to the winged helix family of transcriptional regulators. the qin protein is localized in the nucleus and binds to the same dna consensus sequence as rat brain factor 1 (bf-1). cellular qin shows greater affinity to dna than does viral qin. alone or fused to the dna-binding domain of the yeast gal4 protein, both qin proteins act as transcriptional repressors. the major transcriptional repression domain maps to the region of amino acids ... | 1995 | 7585630 |
| characterization of the progesterone 21-hydroxylase activity of canine cytochrome p450 pbd-2/p450 2b11 through reconstitution, heterologous expression, and site-directed mutagenesis. | canine hepatic cytochrome p450 pbd-2 metabolizes 2,2',4,4',5,5'-hexachlorobiphenyl and catalyzes the 21-hydroxylation of progesterone, thereby distinguishing pbd-2 as unique among 2b p450s. heterologous expression of the pbd-2 cdna, p450 2b11, in cos and yeast systems produced a protein capable of androstenedione metabolism; however, this p450 did not metabolize progesterone in a manner consistent with pbd-2. modification of pbd-2 reconstitution parameters resulted in significantly increased cat ... | 1995 | 7587957 |
| liver fructose-1,6-bisphosphatase cdna: trans-complementation of fission yeast and characterization of two human transcripts. | the sv40 early promoter is active both in mammalian cells and in the fission yeast schizosaccharomyces pombe, and is used to drive full-length cdna in polyvalent pcd-libraries. two such liver libraries, of human and rat origin, were used to trans-complement a s. pombe mutant deficient in fructose-1,6-bisphosphatase (fru-1,6-pase) activity, a key gluconeogenic enzyme restricted to liver, kidney and intestine in mammals. a rat liver fru-1,6-pase cdna was readily cloned and sequenced. complementary ... | 1995 | 7589895 |
| targeting signals and subunit interactions in coated vesicle adaptor complexes. | there are two clathrin-coated vesicle adaptor complexes in the cell, one associated with the plasma membrane and one associated with the tgn. the subunit composition of the plasma membrane adaptor complex is alpha-adaptin, beta-adaptin, ap50, and ap17; while that of the tgn adaptor complex is gamma-adaptin, beta'-adaptin, ap47, and ap19. to search for adaptor targeting signals, we have constructed chimeras between alpha-adaptin and gamma-adaptin within their nh2-terminal domains. we have identif ... | 1995 | 7593184 |
| developmental regulation of the catalytic subunit of the apolipoprotein b mrna editing enzyme (apobec-1) in human small intestine. | apolipoprotein (apo) b mrna editing is a site-specific cytidine deamination reaction responsible for the production of apob-48 in mammalian small intestine. this process is mediated by an enzyme complex that includes the catalytic subunit, apobec-1. in the present study, it is shown that the developmental regulation of apob mrna editing in fetal human small intestine is closely mirrored by accumulation of apobec-1 mrna. similar results were obtained using caco-2 cells, the data further suggestin ... | 1995 | 7595088 |
| yeast synaptobrevin homologs are modified posttranslationally by the addition of palmitate. | yeast possess two homologs of the synaptobrevin family of vesicle-associated membrane proteins that function in membrane recognition and vesicle fusion. yeast proteins snc1 and snc2 localize to secretory vesicles and are required for constitutive exocytosis. they also form a physical complex with a plasma membrane protein, sec9, which is necessary for vesicle docking and fusion to occur in vivo. formation of this molecular complex, as a prerequisite for vesicle fusion, appears to have been conse ... | 1995 | 7597066 |
| dissection of transcription factor tfiif functional domains required for initiation and elongation. | tfiif is unique among the general transcription factors because of its ability to control the activity of rna polymerase ii at both the initiation and elongation stages of transcription. mammalian tfiif, a heterodimer of approximately 30-kda (rap30) and approximately 70-kda (rap74) subunits, assists tfiib in recruiting rna polymerase ii into the preinitiation complex and activates the overall rate of rna chain elongation by suppressing transient pausing by polymerase at many sites on dna templat ... | 1995 | 7597077 |
| petunia hybrida homologues of shaggy/zeste-white 3 expressed in female and male reproductive organs. | petunia hybrida ovule-specific cdna libraries were screened for genes encoding homologues of protein kinases known to be involved in developmental processes. two cdnas, psk4 and psk6 (petunia hybrida shaggy related protein kinase), homologous to gsk-3 from rat, mds1 from yeast and to the segment polarity gene shaggy/zeste-white 3 (sgg/zw3) from drosophila were characterized in detail. southern blot analysis showed that the psk4 and psk6 genes belong to a small multigene family in p. hybrida. the ... | 1995 | 7599650 |
| the usage of oligopeptides in proteins correlates negatively with molecular weight. | we scanned the swissprot databank to study the distribution of oligopeptides in sequenced proteins. we observed that in 7839,000 amino acids in the bank, the frequency is strongly and negatively correlated with molecular weight. the correlation coefficient is -0.63 for single amino acids, -0.58 for dipeptides, -0.54 for tri- and -0.46 for tetrapeptides. in subsets of proteins of man, mouse, rat drosophila, yeast and e. coli, the correlations were very similar to those for the total database. the ... | 1995 | 7601605 |
| variable effects of maturity-onset-diabetes-of-youth (mody)-associated glucokinase mutations on substrate interactions and stability of the enzyme. | mutations in the human glucokinase (gk) gene are thought to cause maturity-onset diabetes of youth (mody) by leading to the production of enzymes with reduced catalytic activities and increased glucose km values. however, in some cases the diabetic phenotype is more severe than might be predicted from these apparent kinetic effects alone. to determine whether these mutations might also effect other characteristics of the enzyme, nine mody-associated mutants were expressed as fusion proteins with ... | 1995 | 7619052 |
| the role of inositol acylation and inositol deacylation in gpi biosynthesis in trypanosoma brucei. | the compound diisopropylfluorophosphate (dfp) selectively inhibits an inositol deacylase activity in living trypanosomes that, together with the previously described phenylmethylsulfonyl fluoride (pmsf)-sensitive inositol acyltransferase, maintains a dynamic equilibrium between the glycosylphosphatidylinositol (gpi) anchor precursor, glycolipid a [nh2(ch2)2po4-6man alpha 1-2man alpha 1-6man alpha 1-4glcn alpha 1-6myo-inositol-1-po4-sn-1,2-dimyristoylglycerol], and its inositol acylated form, gly ... | 1995 | 7621823 |
| identification of yhr068w in saccharomyces cerevisiae chromosome viii as a gene for deoxyhypusine synthase. expression and characterization of the enzyme. | deoxyhypusine synthase catalyzes the formation of deoxyhypusine, the first step in hypusine biosynthesis. amino acid sequences of five tryptic peptides from rat deoxyhypusine synthase were found to match partially the deduced amino acid sequence of the open reading frame of gene yhr068w of saccharomyces cerevisiae chromosome viii (ac:u00061). in order to determine whether the product of this gene corresponds to yeast deoxyhypusine synthase,a 1.17-kilobase pair cdna with an identical nucleotide s ... | 1995 | 7629166 |
| an abundant, trans-spliced mrna from toxocara canis infective larvae encodes a 26-kda protein with homology to phosphatidylethanolamine-binding proteins. | a full-length mrna encoding a secreted 26-kda antigen of infective larvae of the ascarid nematode parasite toxocara canis has been identified. this was characterized as a 1,082-base pair clone highly abundant (0.8-1.9%) in cdna prepared from infective stage larvae but absent from cdna from adult male worms. sequence analysis revealed an open reading frame corresponding to a hydrophilic 263-amino acid residue polypeptide with a 20-residue n-terminal signal peptide, indicating that it is secreted. ... | 1995 | 7629180 |
| mitochondrial respiration scavenges extramitochondrial superoxide anion via a nonenzymatic mechanism. | we determined that mitochondrial respiration reduced cytosolic oxidant stress in vivo and scavenged extramitochondrial superoxide anion (o2-.) in vitro. first, saccharomyces cerevisiae deficient in both the cytosolic antioxidant cupro-zinc superoxide dismutase (cu,zn-sod) and electron transport (rho0 state) grew poorly (p < 0.05) in 21% o2 compared with parent yeast and yeast deficient only in electron transport or cu,zn-sod, whereas anaerobic growth was the same (p > 0.05) in all yeast. second, ... | 1995 | 7635949 |
| molecular cloning of the human gene encoding lanosterol synthase from a liver cdna library. | lanosterol synthase [(s)-2,3-epoxysqualene mutase (cyclizing, lanosterol forming), ec 5.4.99.7] catalyzes the cyclization of (s)-2,3-oxidosqualene to lanosterol in the reaction that forms the sterol nucleus. we report herein the cloning and characterization of the human gene (osc) encoding lanosterol synthase, a predicted 83 kda protein of 732 amino acids. the deduced amino acid sequence is 36-40% identical to known yeast and plant homologues and 83% identical to rattus norvegicus lanosterol syn ... | 1995 | 7639730 |
| class iii alcohol dehydrogenase from saccharomyces cerevisiae: structural and enzymatic features differ toward the human/mammalian forms in a manner consistent with functional needs in formaldehyde detoxication. | alcohol dehydrogenase class iii (glutathione-dependent formaldehyde dehydrogenase) from saccharomyces cerevisiae was purified and analyzed structurally and enzymatically. the corresponding gene was also analyzed after cloning from a yeast genome library by screening with a probe prepared through pcr amplification. as with class iii alcohol dehydrogenase from other sources, the yeast protein was obtained in two active forms, deduced to reflect different adducts/modifications. protein analysis est ... | 1995 | 7649298 |
| cloning and nucleotide sequence of a specific dna fragment from paracoccidioides brasiliensis. | we cloned and sequenced a species-specific 110-bp dna fragment from paracoccidioides brasiliensis. the dna fragment was generated by pcr with primers complementary to the rat beta-actin gene under a low annealing temperature. comparison of the nucleotide sequence, after excluding the primers, with those in the genbank database identified approximately 60% homology with an exon of a major surface glycoprotein gene from pneumocystis carinii and a fragment of unknown function in saccharomyces cerev ... | 1995 | 7650207 |
| solubilization and identification of essential functional groups of candida albicans oxidosqualene cyclase. | the enzyme properties and location of essential functional groups of solubilized oxidosqualene cyclase of candida albicans have been studied. we show that the c. albicans enzyme is much more heat-labile compared with saccharomyces cerevisiae and rat liver cyclases, requires a histidyl residue for enzyme activity, contains an essential thiol residue either close to or in the active site and exhibits a carbocationic mechanism for catalysis, as the enzyme-bound substrate protects the enzyme from in ... | 1995 | 7650579 |
| amino acid sequence of the ribosomal protein hs23 from the halophilic haloarcula marismortui and homology studies to other ribosomal proteins. | the ribosomal protein hs23 from the 30s subunit of the extreme halophilic haloarcula marismortui, belonging to the group of archaea, was isolated either by rp-hlplc or two-dimensional polyacrylamide gel electrophoresis. the complete amino acid sequence was determined by automated n-terminal microsequencing. the protein consists of 123 residues with a corresponding molecular mass of 12,552 da as determined by electrospray mass spectroscopy; the pi is 11.04. homology studies reveal similarities to ... | 1995 | 7662106 |
| cloning and functional expression of the cdna encoding rat lanosterol 14-alpha demethylase. | lanosterol 14 alpha-demethylase (ldm) is a cytochrome p-450 enzyme in the biosynthetic pathway of cholesterol. as such, it represents a target for cholesterol-lowering drugs. rat ldm (rldm) has been purified from the livers of rats treated with cholestyramine. the purified protein was used to generate tryptic fragments which were then sequenced. the amino acid (aa) sequences were used to design oligodeoxyribonucleotide primers and a dna fragment was generated by rt-pcr to probe a phagemid librar ... | 1995 | 7665087 |
| peroxisome structure, function, and biogenesis--human patients and yeast mutants show strikingly similar defects in peroxisome biogenesis. | peroxisomes are found in almost all eukaryotic cells. two major functions of the organelle are in lipid metabolism: peroxisomes catalyze the initial steps in the biosynthesis of plasmalogens, which are phospholipids that are present in large amounts in myelin. peroxisomes also catalyze the beta-oxidation of fatty acids; this pathway is essential for the catabolism of a variety of substrates that are not oxidized by mitochondria. a third important function is in cellular respiration, involving th ... | 1995 | 7666062 |
| n-oxygenation of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine by the rat liver flavin-containing monooxygenase expressed in yeast cells. | n-oxygenation of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (mptp), a dopaminergic neurotoxin, was studied using recombinant rat liver flavin-containing monooxygenase (fmo), fmo1a1, expressed in yeast cells. the mean (+/- s.d.) kinetic parameters of mptp n-oxygenation were: km = 1.8 +/- 0.5 microm, vmax = 9.5 +/- 1.6 nmol/mg per min, and vmax/km = 4.6 +/- 0.5 ml/mg per min. n-octylamine, an activator of fmo, enhanced the mptp n-oxygenation activity by 51%, while methimazole, thiobenzamide and ... | 1995 | 7672012 |
| cloning and expression of human deoxyhypusine synthase cdna. structure-function studies with the recombinant enzyme and mutant proteins. | deoxyhypusine synthase catalyzes the first step in the post-translational formation of hypusine (n epsilon-(4-amino-2-hydroxybutyl)lysine). cdna clones encoding deoxyhypusine synthase were isolated from a human hela cell library. full-length cdna clones encoding a 369-amino acid protein (calculated molecular mass of 40,970 da) and a shorter cdna clone that would potentially encode a protein with an internal deletion of 56 amino acids (asp262-ser317) were isolated. the deduced amino acid sequence ... | 1995 | 7673224 |
| secondary structure of rnase mrp rna as predicted by phylogenetic comparison. | rnase mrp is a ribonucleoprotein endoribonuclease that has been shown to cleave mitochondrial primer rna sequences from a variety of sources. the bulk of rnase mrp activity is found in the nucleus where its function remains unknown. two different approaches have resulted in predictions of distinct secondary structures for rnase mrp rna. in order to analyze more definitively the higher-order structure of rnase mrp rna, we have conducted a phylogenetic comparison of the available rnase mrp rna seq ... | 1993 | 7678563 |
| cytotoxic and genotoxic properties of tert.-butyl-p-quinone (tbq) in an in vitro assay system with chinese hamster v79 cells and in strain d7 of saccharomyces cerevisiae. | tert.-butyl-p-quinone (tbq), a major metabolite of the phenolic antioxidant tert.-butyl-4-hydroxyanisole (bha), was examined for cytotoxic and genotoxic properties in an in vitro assay system with chinese hamster v79 cells and in diploid strain d7 of saccharomyces cerevisiae. tbq was prepared from bha by oxidative demethylation with sodium nitrite at low ph. spectroscopic analyses identified the crystalline reaction product as tbq with a purity close to 100%. cytotoxicity of tbq was determined b ... | 1993 | 7679195 |
| sap90, a rat presynaptic protein related to the product of the drosophila tumor suppressor gene dlg-a. | a novel synapse-associated protein, sap90, accumulates around the axon hillock of purkinje cells in rat cerebellum. by immuno-electron microscopy, sap90 has been localized to the presynaptic termini of basket cells forming inhibitory, gamma-aminobutyric acid (gaba)ergic synapses onto purkinje cell axon hillocks. the amino acid sequence for sap90 has been deduced from the nucleotide sequence of a series of overlapping cdna clones. sap90 is related to the gene product encoded by the drosophila tum ... | 1993 | 7680343 |
| analysis of conserved binding proteins for nuclear localization sequences. | correct targeting of nuclear proteins is mediated by nuclear localization sequences (nls) which permit specific binding to the nucleus and subsequent translocation across the nuclear envelope via the nuclear pore complex. it is proposed that nuclear import is facilitated by nls-receptors which reside in the cytoplasm and at the nuclear pore. these nls-receptors could facilitate an early step of nuclear protein import, i.e. targeting and binding of nuclear proteins at the nuclear pore. we have ge ... | 1993 | 7680661 |
| expression and localization of two low molecular weight gtp-binding proteins, rab8 and rab10, by epitope tag. | small gtp-binding proteins of the ypt/sec4/rab family have been shown to play an essential role in intracellular membrane trafficking. in mammals, rab8 and rab10 are the two small gtp-binding proteins identified so far that are closest to sec4, an essential gene product involved in post-golgi constitutive secretion in the yeast saccharomyces cerevisiae. to study the localization of rab proteins, we have expressed the cdnas with an influenza virus hemagglutinin (ha) epitope tag at the n terminus. ... | 1993 | 7688123 |
| mineral status in selenium-deficient rats compared to selenium-sufficient rats fed vitamin-free casein-based or torula yeast-based diet. | to clarify the mineral status in selenium (se)-deficient rats fed a vitamin-free casein (vfc)-based or torula yeast (ty)-based diet, 24 weanling male wistar rats were divided into 4 groups fed diets using vfc or ty as the protein source and containing se at sufficient (0.5 microgram/g, +se) or deficient (0.019 microgram/g for vfc-based and < 0.005 microgram/g for ty-based diets, -se) level for 8 wk. ty supplied a larger amount of extra minerals (na, k, ca, mg, fe, mn, zn, and cu) except se than ... | 1993 | 7688535 |
| expression in escherichia coli, purification and functional activity of recombinant human chaperonin 10. | we have recently reported the cloning of a cdna coding for a stress inducible human chaperonin 10. the protein was shown to possess 100% identity with the bovine homologue and a single amino acid replacement (glycine to serine at position 52) compared to rat chaperonin 10. here we report the heterologous expression of human chaperonin 10 in escherichia coli, its purification and its functional characterization. the recombinant protein was purified to homogeneity as judged by different analytical ... | 1995 | 7698325 |
| rbsec1a and b colocalize with syntaxin 1 and snap-25 throughout the axon, but are not in a stable complex with syntaxin. | rbsec1 is a mammalian neuronal protein homologous to the yeast sec1 gene product which is required for exocytosis. mutations in sec1 homologues in the nervous systems of c. elegans and d. melanogaster lead to defective neurotransmitter secretion. biochemical studies have shown that recombinant rbsec1 binds syntaxin 1 but not snap-25 or synaptobrevin/vamp, the two proteins which together with syntaxin 1 form the synaptic snare complex. in this study we have examined the subcellular localization o ... | 1995 | 7698978 |
| affinity-purification and identification of grpe homologues from mammalian mitochondria. | we used affinity chromatography on dnak columns to identify a mitochondrial grpe homologue from bovine, porcine and rat liver mitochondria. the 24 kda grpe homologue bound specifically to the dnak column and was not eluted with 1 m kcl but readily with 5 mm atp. sequence analysis of the bovine homologue (85 residues) revealed 42% positional identity to mitochondrial grpep from s. cerevisiae and about 30% identity to the bacterial counterparts. thus, grpe homologues from higher and lower eukaryot ... | 1995 | 7711059 |
| the protooncogene c-jun contains an unusual estrogen-inducible enhancer within the coding sequence. | estrogens have previously been shown to induce c-jun mrna levels in target cells during hormone induced proliferation, and this appears to be a primary hormonal response involving transcriptional activation. in this report we have now identified an estrogen dependent enhancer within the coding sequence of c-jun. this element has the sequence gcagannntgacc which is identical to the consensus estrogen response element ggtcannntgacc in the second half site, but varies considerably in the first half ... | 1995 | 7721748 |
| multiple promoters in rat acyl-coa synthetase gene mediate differential expression of multiple transcripts with 5'-end heterogeneity. | nucleotide sequence analysis of six independently isolated cdnas for rat acyl-coa synthetase (acs) revealed three forms of acs mrna, designated form-a, -b, and -c mrnas, which differ in their 5'-untranslated regions. form-a mrna was preferentially detected in normal and peroxisome-induced livers, whereas form-b mrna was found in peroxisome-induced livers but not in normal livers and hearts, and form-c mrna was preferentially found in normal hearts and peroxisome-induced livers. analysis of two o ... | 1995 | 7721900 |
| transcription factor genes from rat pneumocystis carinii. | genes encoding the tfiid tata-box binding protein (tbp) from two probable species of rat pneumocystis carinii (prototype and variant) were sequenced. the two p. carinii tbp gene sequences were 91% identical to each other, and 65-77% identical to tbp genes from other species. a cdna from one of the two p. carinii tbp genes was sequenced, which showed that four small introns resided in identical positions within the tbp genes from the prototype and variant rat p. carinii. conservation of the 180 a ... | 1995 | 7728137 |
| drosophila udp-glucose:glycoprotein glucosyltransferase: sequence and characterization of an enzyme that distinguishes between denatured and native proteins. | a drosophila udp-glucose:glycoprotein glucosyltransferase was isolated, cloned and characterized. its 1548 amino acid sequence begins with a signal peptide, lacks any putative transmembrane domains and terminates in a potential endoplasmic reticulum retrieval signal, hgel. the soluble, 170 kda glycoprotein occurs throughout drosophila embryos, in microsomes of highly secretory drosophila kc cells and in small amounts in cell culture media. the isolated enzyme transfers [14c]glucose from udp-[14c ... | 1995 | 7729408 |
| localization of i2-imidazoline binding sites on monoamine oxidases. | imidazoline binding sites (ibs) were proposed to be responsible for some of the pharmacological and therapeutic activities of imidazoline and related compounds and have been classified into two subtypes, i1bs and i2bs. convergent studies attribute a role in central blood pressure regulation to the i1bs. in contrast, the function of i2bs remains unknown. in the present study, by combining biochemical and molecular biology approaches, we show that 1) microsequencing of i2bs purified from rabbit ki ... | 1995 | 7730367 |
| immunotechnological trends in radioimmunotargeting: from 'magic bullet' to 'smart bomb'. | the impact of recent advances in the chemical and genetic engineering manipulations of antibodies on radioimmunotargeting is reviewed both in relation to radioimmunoscintigraphy and radioimmunotherapy. the resulting trends are: (1) the linking of parts of the mouse/rat and human antibody molecule; (2) the creation of molecules with dual antigen or multiple antigen recognition capabilities; (3) the making of smaller and smaller antigen recognition molecules; and (4) the development of molecules w ... | 1995 | 7731620 |
| the hepatitis b virus x protein targets the basic region-leucine zipper domain of creb. | the x gene product encoded by the hepatitis b virus, termed px, is a promiscuous transactivator of a variety of viral and cellular genes under the control of diverse cis-acting elements. although px does not appear to directly bind dna, px-responsive elements include the nf-kappa b, ap-1, and cre (camp response element) sites. direct protein-protein interactions occur between viral px and the cre-binding transcription factors creb and atf. here we examine the mechanism of the protein-protein int ... | 1995 | 7731990 |
| the peptide repeat domain of nucleoporin nup98 functions as a docking site in transport across the nuclear pore complex. | we report the cdna deduced primary structure of a wheat germ agglutinin-reactive nuclear pore complex (npc) protein of rat. the protein, termed nup98 (for nucleoporin of 98 kda), contains numerous glfg and fg repeats and some fxfg repeats and is thus a vertebrate member of a family of glfg nucleoporins that were previously discovered in yeast. immunoelectron microscopy showed nup98 to be asymmetrically located at the nucleoplasmic side of the npc. nup98 functions as one of several docking site n ... | 1995 | 7736573 |
| scaled-up expression of human alpha 2,6(n)sialyltransferase in saccharomyces cerevisiae. | expression of recombinant full length human alpha 2,6(n)sialyltransferase has been scaled-up in s. cerevisiae in a 150-l bioreactor yielding 47 u at a concentration of 0.31 u/l. the protein specific activity as measured in reconstituted yeast lyophilisate was 0.8 mu/mg protein. the recombinant enzyme exhibited similar michaelis constants as previously determined for the native rat enzyme. by immunoblotting the enzyme was shown to be heterogeneous by size (44-48 kd) and n-glycosylated. we conclud ... | 1995 | 7741734 |
| molecular cloning and characterization of cdna encoding the alpha subunit of the rat protein synthesis initiation factor eif-2b. | eukaryotic initiation factor 2b (eif-2b) is an essential component of the pathway of peptide-chain initiation in mammalian cells, yet little is known about its molecular structure and regulation. to investigate the structure, regulation, and interactions of the individual subunits of eif-2b, we have begun to clone, characterize, and express the corresponding cdnas. we report here the cloning and characterization of a 1510-bp cdna encoding the alpha subunit of eif-2b from a rat brain cdna library ... | 1995 | 7753796 |
| cloning and identification of arp1, an actin-related protein from pneumocystis carinii. | the complete pneumocystis carinii arp1 gene has been sequenced from two cdna clones. the gene encodes a protein 385 bp in length with an estimated size of 45,000 kd. the a + t% for the arp1 gene and a 900-bp sequence upstream of the gene were 63.7% and 70.3%, respectively. these values are consistent with a + t codon preference displayed by p. carinii and are similar to values reported for other p. carinii genes. the predicted amino acid sequence of the p. carinii arp1 protein had a similarity o ... | 1995 | 7757056 |
| kinetic characteristics of rat liver peroxisomal nafenopin-coa ligase. | in this study we have demonstrated that rat hepatic peroxisomes catalyse the formation of nafenopin-coa. the process is mediated by apparent high affinity (km 6.7 microm), low capacity (vmax 0.31 nmol/mg/min) and low affinity, high capacity isoforms. palmitic acid (ki 1.1 microm), r(-) ibuprofen (ki 7.9 microm), ciprofibrate (ki 60.2 microm) and clofibric acid (ki 86.8 microm) competitively inhibited nafenopin-coa formation catalysed by the apparent high affinity isoform. an antibody raised agai ... | 1995 | 7763316 |
| high-level expression of human lipocortin i in the fission yeast schizosaccharomyces pombe using a novel expression vector. | we have developed a novel expression system that allows the fission yeast, schizosaccharomyces pombe, to be used for the efficient overproduction of heterologous proteins. as an example of the utility of this system, human lipocortin i was expressed to 50 percent of soluble protein, and 150 mg of highly purified material was obtained from 10 grams of wet cell paste. expression of lipocortin i was driven by the human cytomegalovirus (hcmv) promoter in a vector that also contains a neomycin resist ... | 1994 | 7764687 |
| comparing nucleotide and protein sequences by linguistic methods. | nucleotide and amino acid sequences can be analyzed and compared by their oligomer compositions. such methods are fundamentally different from comparison methods based on sequence alignment. they are analogous to the linguistic analysis of human texts. the methods have a wide range of sensitivity and can identify homologous as well as functionally and taxonomically related sequences. significant sequence dissimilarity can also be identified enabling detection of foreign dna sequences in genomes, ... | 1994 | 7765062 |
| a novel ubiquitous form of munc-18 interacts with multiple syntaxins. use of the yeast two-hybrid system to study interactions between proteins involved in membrane traffic. | munc-18-1 is a 67-kda neuronal protein that binds tightly to syntaxin 1 and functions in synaptic vesicle exocytosis (hata, y., slaughter, c.a., and südhof, t.c. (1993a) nature 366, 347-351). we have now characterized a new munc-18 isoform, munc-18-2, that exhibits 63% amino acid sequence identity with munc-18-1. munc-18-2 is expressed in most tissues, whereas munc-18-1 is primarily expressed in brain. using recombinant munc-18-1 and munc-18-2 produced in cos cells, we show that both forms of mu ... | 1995 | 7768895 |
| identification of a nuclear receptor that is activated by farnesol metabolites. | nuclear hormone receptors comprise a superfamily of ligand-modulated transcription factors that mediate the transcriptional activities of steroids, retinoids, and thyroid hormones. a growing number of related proteins have been identified that possess the structural features of hormone receptors, but that lack known ligands. known as orphan receptors, these proteins represent targets for novel signaling molecules. we have isolated a mammalian orphan receptor that forms a heterodimeric complex wi ... | 1995 | 7774010 |
| carbethoxylating agents as inhibitors of aldehyde dehydrogenase. | n,o-dicarbethoxy-4-chlorobenzenesulfohydroxamate (1c) and o-carbethoxy-n-hydroxysaccharin (6), both potential carbethoxylating agents, inhibited yeast aldehyde dehydrogenase (aldh) with ic50's of 24 and 56 microm, respectively. the esterase activity of the enzyme was commensurably inhibited. aldh activity was only partially restored on incubation with mercaptoethanol (20 mm) for 1 h. on incubation with rat plasma, 1c liberated nitroxyl, a potent inhibitor of aldh. under the same conditions, nitr ... | 1995 | 7783119 |
| 2,3-oxidosqualene cyclase: from azasqualenes to new site-directed inhibitors. | 2,3-oxidosqualene cyclases (osc) are enzymes which convert 2,3-oxidosqualene (os) into polycyclic triterpenoids such as lanosterol, cycloartenol, and alpha- and beta-amyrin. our interest in the study of osc is the development of new osc inhibitors for potential use as hypocholesterolemic, antifungal, or phytotoxic drugs. in particular, we describe the biological activity and the mechanism of a series of acyclic azasqualene derivatives mimicking the c-2, c-8, and c-20 carbonium ions formed during ... | 1995 | 7791532 |
| evidence from antibody studies that the cag repeat in the huntington disease gene is expressed in the protein. | the neurodegenerative disorder huntington disease (hd) appears to be caused by an increase in the number of repeats of the trinucleotide cag located near the 5' end of the gene. the nucleotide sequences of the cdna and the gene predict that the hd protein has a molecular weight of 347,000 (3144 amino acids) and that the cag repeats encode a segment of polyglutamine beginning 17 amino acids from the amino terminus. because the cag repeat plays such a critical role in the etiology of the disease, ... | 1995 | 7795604 |
| purification of phosphatidylinositol transfer protein from brain cytosol for reconstituting g-protein-regulated phosphoinositide-specific phospholipase c-beta isozymes. | | 1994 | 7799783 |
| use of fluorescent probes to investigate the metabolic state of pneumocystis carinii mitochondria. | | 1994 | 7804275 |
| tamoxifen and estrogens as membrane antioxidants: comparison with cholesterol. | | 1994 | 7808336 |
| site-directed mutagenesis of the peripheral benzodiazepine receptor: identification of amino acids implicated in the binding site of ro5-4864. | the peripheral benzodiazepine receptor (pbr) is an 18-kda protein present in the outer mitochondrial membrane. the human pbr can be labeled with the benzodiazepine ro5-4864 and with the isoquinoline carboxamide pk11195. the two ligands compete with each other in binding experiments, with previous results suggesting overlapping but not identical binding sites. to define the regions of the receptor interacting with pk11195 and ro5-4864 and to address the question of the topology of the molecule in ... | 1994 | 7808437 |
| energy transfer assays of rat renal cortical endosomal fusion: evidence for superfusion. | the complex of components necessary to allow endosomal fusion includes both membrane-bound receptors and several soluble proteins. although these factors have been isolated from cultured cell lines, and endosomal fusion has been reconstituted in vitro for vesicular systems from yeast to synaptosomes, there is a paucity of data from mammalian systems. to investigate fusion in rat renal cortical endosomes, we began by developing a fusion assay. as the immunoglobulin and avidin-based probes almost ... | 1994 | 7810689 |
| requirement of tyrosine- and serine/threonine kinases in the transcriptional activation of the mammalian grp78/bip promoter by thapsigargin. | depletion of endoplasmic reticulum (er) ca2+ store by thapsigargin (tg) in mammalian cells induces a set of er protein genes known as the glucose-regulated proteins. recently, ire1p, a transmembrane protein postulated to have a serine/threonine kinase activity, has been identified as required for the induction of er resident proteins genes in saccharomyces cerevisiae. to investigate whether ire1p can stimulate mammalian grp transcription, a stable chinese hamster ovary cell line containing ampli ... | 1995 | 7814417 |
| ca2+ transport in saccharomyces cerevisiae. | cytosolic free ca2+ is maintained at submicromolar levels in budding yeast by the activity of ca2+ pumps and antiporters. we have recently identified the structural genes for two ca2+ pumps, pmc1 [correction of pcm1] and pmr1, which are required for ca2+ sequestration into the vacuole and secretory organelles, respectively. the function of either ca2+ pump is sufficient for yeast viability, but deletion of both genes is lethal because of elevation of cytosolic [ca2+] and activation of calcineuri ... | 1994 | 7823019 |
| distribution of the kexin family proteases in pancreatic islets: pace4c is specifically expressed in b cells of pancreatic islets. | the distribution of kexin family proteases in adult rat pancreatic islets was investigated by immunohistochemical means using a series of specific antibodies specific for pc1, pc2, pc6, furin, pace4a and a recently identified member of the kexin family, pace4c. pace4c expression was limited to b cells of the pancreatic islets. pc2 was found in a and in some d cells more than in b cells and pc1 was evident only in b cells. furin and pc6 were weakly and evenly expressed in the entire islet. pace4a ... | 1995 | 7828552 |
| p115 is a general vesicular transport factor related to the yeast endoplasmic reticulum to golgi transport factor uso1p. | a recently discovered vesicular transport factor, termed p115, is required along with n-ethylmaleimide-sensitive fusion protein (nsf) and soluble nsf attachment proteins for in vitro golgi transport. p115 is a peripheral membrane protein found predominantly on the golgi. biochemical and electron microscopic analyses indicate that p115 is an elongated homodimer with two globular "heads" and an extended "tail" reminiscent of myosin ii. we have cloned and sequenced cdnas for bovine and rat p115. th ... | 1995 | 7831323 |
| [acute toxicity of pyrrolizidine alkaloids in the "yeast test"]. | | 1994 | 7838885 |
| molecular cloning and functional expression in yeast of a human camp-specific phosphodiesterase subtype (pde iv-c). | we have recently reported increased survival of dopaminergic substantia nigra neurons by inhibition of phosphodiesterase type iv enzymes. as a first step to unravel the involvement of pde iv subtypes in this process, we isolated phosphodiesterase type iv cdnas from human substantia nigra. one isolated partial cdna clone was most homologous to the partially cloned rat and human pde iv-c isogene. distribution analysis revealed that the enzyme is expressed in various tissues but not in cells of the ... | 1995 | 7843419 |