| evaluation of the sa locus in human hypertension. | the sa gene is expressed at 10-fold greater levels in the kidney of the spontaneously hypertensive rat compared with the normotensive wistar-kyoto rat. the gene is linked to blood pressure levels in a number of crosses involving the spontaneously hypertensive rat and other strains of genetically hypertensive rats. to assess its role in human hypertension, a human sa cdna was cloned from a liver library. the cdna was 1513 bp in length and exhibited a high identity with the published rat sa cdna s ... | 1995 | 7843754 |
| mitochondrial atp-dependent protease from rat liver and yeast. | | 1994 | 7845220 |
| mepyramine, a histamine h1 receptor antagonist, inhibits the metabolic activity of rat and human p450 2d forms. | the interaction of antihistaminics, including mepyramine, with rat hepatic cytochrome p450s (p450s) was investigated. we first investigated mepyramine binding to eight forms of rat hepatic p450s. mepyramine bound specifically to p450 2d1, which suggests that it inhibits p450 2d activity. histamine h1 receptor antagonists (mepyramine, diphenhydramine, chlorpheniramine and triprolidine) inhibited the lidocaine 3-hydroxylation activity catalyzed by p450 2d1 but did not inhibit the testosterone hydr ... | 1995 | 7853212 |
| genetic dissection of thyroid hormone receptor beta: identification of mutations that separate hormone binding and transcriptional activation. | the thyroid hormone receptors (tr) are members of the nuclear receptor family of ligand-mediated transcription factors. the large region of tr that lies c-terminal to its dna-binding domain subserves functions of ligand binding, dimerization, and transactivation. little is known regarding the structural or functional determinants of these processes. we have utilized genetic screening in the yeast saccharomyces cerevisiae to identify residues involved in these functions. random mutations of the r ... | 1995 | 7862143 |
| the ligand-binding domains of the thyroid hormone/retinoid receptor gene subfamily function in vivo to mediate heterodimerization, gene silencing, and transactivation. | the ligand-binding domains (lbds) of the thyroid/retinoid receptor gene subfamily contain a series of heptad motifs important for dimeric interactions. this subfamily includes thyroid hormone receptors (t3rs), all-trans retinoic acid (ra) receptors (rars), 9-cis ra receptors (rars and retinoid x receptors [rxrs]), the 1,25-dihydroxyvitamin d3 receptor (vdr), and the receptors that modulate the peroxisomal beta-oxidation pathway (ppars). these receptors bind to their dna response elements in vitr ... | 1995 | 7862171 |
| amino acid sequence of rat kidney glutathione synthetase. | glutathione (gsh) synthetase [gamma-l-glutamyl-l-cysteine:glycine ligase (adp-forming), ec 6.3.2.3], an enzyme present in almost all cells, catalyzes the atp-dependent synthesis of gsh from gamma-l-glutamyl-l-cysteine and glycine. highly purified preparations of the enzyme have been obtained from rat kidney and several lower forms. the rat kidney enzyme (m(r), 118,000), which contains approximately 2% carbohydrate, is composed of two apparently identical subunits. the cdna encoding rat kidney gs ... | 1995 | 7862666 |
| inhibitors of pig kidney trehalase. | trehazolin, a new trehalase inhibitor isolated from the culture broth of micromonospora, was reported to be a highly specific inhibitor for porcine and silk worm trehalases with ic50 values of 5.5 x 10(-9) and 3.7 x 10(-9) m, respectively (o. ando, h. satake, k. itoi, a. sato, m. nakajima, s. takashi, h. haruyama, y. ohkuma, t. kinoshita, and r. enokita (1991) j. antibiot. 44, 1165-1168). we also found that trehazolin is a very powerful and quite specific inhibitor against purified pig kidney tr ... | 1995 | 7864639 |
| the functional expression of a rat cdna encoding oscp in the yeast saccharomyces cerevisiae. | the oligomycin sensitivity conferring protein (oscp) of saccharomyces cerevisiae is a component of the stalk fa sector of the mitochondrial f1fo-atp synthase complex (mtatpase). the subunits comprising this sector have been implicated in the coupling of proton flux through the membrane fo sector to atp synthesis on the catalytic f1 sector. we tested whether the yeast subunit encoded by the atp5 gene could be functionally replaced by a mammalian homologue, rat oscp. the yeast and rat oscp protein ... | 1995 | 7864899 |
| nucleotide binding by the synapse associated protein sap90. | the rat synapse associated protein sap90 is a member of a superfamily of potential guanylate kinases localized at cell-cell contact sites. this superfamily includes the synapse associated protein sap97, a close relative of sap90, the drosophila tumor suppressor gene product dlg-ap, the mammalian zonula occludens proteins zo-1 and zo-2 and the erythrocyte protein p55. here we show that sap90 specifically binds gmp in the micromolar range while binding to atp, gdp and adp is at a much lower affini ... | 1995 | 7867790 |
| antinociceptive and antipyretic effects of alkaloids extracted from the stem bark of hunteria zeylanica. | effects of crude alkaloids extracted from the stem bark of hunteria zeylanica gard. (h. zeylanica) on nociceptive responses, capillary permeability, yeast-induced hyperthermia, pentobarbital-induced sleep, and spontaneous motor activity were investigated. oral administration of 50 mg/kg h. zeylanica alkaloid extract significantly decreased the number of writhings induced by intraperitoneal acetic acid. the extract at 100-200 mg/kg significantly increased nociceptive threshold of the inflamed but ... | 1994 | 7874056 |
| reconstituted nuclei depleted of a vertebrate glfg nuclear pore protein, p97, import but are defective in nuclear growth and replication. | xenopus egg extracts provide a powerful system for in vitro reconstitution of nuclei and analysis of nuclear transport. such cell-free extracts contain three major n-acetylglucosaminylated proteins: p200, p97, and p60. both p200 and p60 have been found to be components of the nuclear pore. here, the role of p97 has been investigated. xenopus p97 was isolated and antisera were raised and affinity purified. immunolocalization experiments indicate that p97 is present in a punctate pattern on the nu ... | 1995 | 7876300 |
| recombinant rat cbf-c, the third subunit of cbf/nfy, allows formation of a protein-dna complex with cbf-a and cbf-b and with yeast hap2 and hap3. | the ccaat binding factor cbf is a heteromeric transcription factor, which binds to functional ccaat motifs in many eukaryotic promoters. cdnas for the a and b subunits of cbf (cbf-a and cbf-b) and for their yeast homologues hap3 and hap2 have been previously isolated, but the purified recombinant cbf-a and cbf-b together are unable to bind to ccaat motifs in dna. here we report the isolation of a cdna coding for rat cbf-c, demonstrate that recombinant cbf-c is required together with cbf-a and cb ... | 1995 | 7878029 |
| production, purification and characterization of recombinant yeast processing alpha 1,2-mannosidase. | the saccharomyces cerevisiae processing alpha 1,2-mannosidase, which trims man9glcnac to man8glcnac, has a lumenally oriented catalytic domain and an n-terminal transmembrane domain. to obtain sufficient protein to study the structure and mechanism of action of this enzyme, the sequence encoding the catalytic domain was inserted downstream of the alpha-factor promoter and signal peptide in a high-copy vector for expression in s. cerevisiae as a secreted protein. using oligosaccharide substrate ( ... | 1994 | 7881184 |
| cloning and functional characterization of a mammalian zinc transporter that confers resistance to zinc. | a cdna encoding a zinc transporter (znt-1) was isolated from a rat kidney cdna expression library by complementation of a mutated, zinc-sensitive bhk cell line. this cdna was used to isolate the homologous mouse znt-1 gene. the proteins predicted for these transporters contain six membrane-spanning domains, a large intracellular loop and a c-terminal tail. znt-1 is homologous to zinc and cobalt resistance genes of yeast. immunocytochemistry with an antibody to a myc epitope added to the c-termin ... | 1995 | 7882967 |
| chemical reagents as potential impurities of pharmaceutical products: investigations on their genotoxic activity. | the genotoxic activity of chemical reagents and intermediates as potential impurities of final pharmaceutical products have been investigated by the afi mutagenesis study group. a number of compounds employed in the synthesis of beta-lactam (12), quinolone (6), antiviral (3), and other drugs (11) were analyzed. the information reported in this article was mainly obtained experimentally in our laboratories. in addition, attempts were made to obtain reference data; however, these were available fo ... | 1994 | 7884648 |
| human alpha-tocopherol transfer protein: cdna cloning, expression and chromosomal localization. | alpha-tocopherol transfer protein (alpha ttp), which specifically binds this vitamin and enhances its transfer between separate membranes, was previously isolated from rat liver cytosol. in the current study we demonstrated the presence of alpha ttp in human liver by isolating its cdna from a human liver cdna library. the cdna for human alpha ttp predicts 278 amino acids with a calculated molecular mass of 31,749, and the sequence exhibits 94% similarity with rat alpha ttp at the amino acid leve ... | 1995 | 7887897 |
| molecular cloning and expression, in both cos-1 cells and s. cerevisiae, of a human cytosolic type-iva, cyclic amp specific phosphodiesterase (hpde-iva-h6.1). | screening a human t lymphocyte cdna library with a phosphodiesterase (pde) specific probe resulted in the isolation of two overlapping cdna clones, h2.2 and h6.1, that encode a type iv, rolipram inhibited camp-specific pde. clones h2.2 and h6.1 were 1015 bp and 2288 bp in length, respectively, and overlapped for 984 bp with only one nucleotide difference. the h6.1 cdna was extended at the 5'-end by 1304 bp, with respect to h2.2, and encoded an incomplete orf (lacking an initiation codon) of 668 ... | 1994 | 7888306 |
| cloning and characterisation of multiple acetyl-coa carboxylase transcripts in ovine adipose tissue. | a full-length ovine acetyl-coa carboxylase-encoding cdna (acc) has been cloned from adipose tissue and completely sequenced. the open reading frame of 7041 nucleotides (nt) is highly homologous to the previously cloned human, rat, chicken, yeast and algal acc (85, 89, 82, 54 and 54% identity, respectively). transcript heterogeneity was found in the 5' and 3' untranslated regions (utr) resulting in acc transcripts in the range of 9.0 kb to 9.4 kb. heterogeneity at the 5' end was generated by the ... | 1995 | 7890176 |
| golgi localization in yeast is mediated by the membrane anchor region of rat liver sialyltransferase. | to investigate the function of the membrane anchor region of a mammalian glycosyltransferase in yeast we constructed a fusion gene that encodes the 34 amino-terminal residues of rat liver beta-galactoside alpha-2,6-sialyl-transferase (ec 2.4.99.1) (st) fused to the mature form of yeast invertase. transformants of saccharomyces cerevisiae expressing the fusion gene produced an intracellular heterogeneously n-glycosylated fusion protein of intermediate molecular weight between the core and fully e ... | 1995 | 7890665 |
| cloning and identification of amino acid residues of human phospholipase c delta 1 essential for catalysis. | in vitro single point mutagenesis, inositol phospholipid hydrolysis, and substrate protection experiments were used to identify catalytic residues of human phosphatidylinositide-specific phospholipase c delta 1 (plc delta 1) isolated from a human aorta cdna library. invariant amino acid residues containing a functional side chain in the highly conserved x region were changed by in vitro mutagenesis. most of the mutant enzymes were still able to hydrolyze inositol phospholipid with activity rangi ... | 1995 | 7890667 |
| cloning, expression, and characterization of cdnas encoding arabidopsis thaliana squalene synthase. | we have isolated and characterized two overlapping cdna clones for arabidopsis thaliana squalene synthase. their nucleotide sequences contained an open reading frame for a 410-amino acid polypeptide (calculated molecular mass, 47 kda). the deduced amino acid sequence of the arabidopsis polypeptide was significantly homologous (42-44% identical) to the sequences of known squalene synthases of several species, from yeast to man, but it was much less homologous to that of tomato phytoene synthase. ... | 1995 | 7892265 |
| control of de novo purine biosynthesis genes in ureide-producing legumes: induction of glutamine phosphoribosylpyrophosphate amidotransferase gene and characterization of its cdna from soybean and vigna. | soybean (glycine max) and mothbean (vigna aconitifolia) cdna clones encoding glutamine phosphoribosylpyrophosphate amidotransferase (prat), the first enzyme of the de novo purine biosynthesis pathway, have been isolated from nodule cdna libraries. the amino acid sequence deduced from soybean clone showed > 85% homology to the prat sequence of mothbean and 33-47% homology to those of bacteria, yeast, chicken, rat and human. the soybean clone encodes a protein with an n-terminal sequence resemblin ... | 1995 | 7894513 |
| distribution and regulation of the candidate prohormone processing enzymes spc2 and spc3 in adult rat brain. | a number of candidate mammalian prohormone processing enzymes related to the yeast kex2 endoprotease have been cloned and demonstrated to cleave several prohormone precursors at single, pairs and tetra basic amino acid processing sites. we have mapped the distribution of the mrnas encoding two of these endoproteases in adult rat brain. spc3 message levels showed a more restricted distribution and generally lower levels than spc2 transcripts. the highest levels of spc2 mrna were found in the pyra ... | 1994 | 7898639 |
| studies on wheat acetyl coa carboxylase and the cloning of a partial cdna. | wheat germ acetyl coa carboxylase (accase) was purified by liquid chromatography and electroelution. during purification bovine serum albumin (bsa) was used to coat amicon membranes used to concentrate partially pure accase. despite further sds-page/electroelution and microbore hplc steps bsa remained associated. this presented serious protein sequencing artefacts which may reflect the affinity of bsa for fatty acids bound to accase. to avoid these artefacts the enzyme was digested in gel with e ... | 1994 | 7906561 |
| characteristics of the gene that encodes acetyl-coa carboxylase in the diatom cyclotella cryptica. | efforts are currently under way in several laboratories to develop renewable fuels from biological sources. our group conducts research involving the production of lipid-derived "biodiesel" fuel from microscopic algae. lipid accumulation in algae typically occurs during periods of environmental stress, including growth under nutrient-deficient conditions. biochemical studies have suggested that acetyl-coa carboxylase (accase), a biotin-containing enzyme that catalyzes an early step in fatty acid ... | 1994 | 7912057 |
| developmental and hormonal regulation of the xenopus liver-type arginase gene. | liver-type l-arginase is a major urea-cycle enzyme which is strongly induced during amphibian metamorphosis, but little is known about the molecular mechanisms underlying this induction. as a first step towards elucidating the possible mechanisms, we have isolated a cdna clone for l-arginase from an adult xenopus laevis liver cdna library. sequence comparison of xenopus liver-type l-arginase cdna shows a strong conservation at the amino acid level with those of human, rat and yeast. using a xeno ... | 1993 | 7916684 |
| primary structure and expression of a human ctp:phosphocholine cytidylyltransferase. | human ctp:phosphocholine cytidylyltransferase (ct) cdnas were isolated by pcr amplification of a human erythroleukemic k562 cell library. initially two degenerate oligonucleotide primers derived from the sequence of the rat liver ct cdna were used to amplify a centrally located 230 bp fragment. subsequently overlapping 5' and 3' fragments were amplified, each using one human ct primer and one vector-specific primer. two cdnas encoding the entire translated domain were also amplified. the human c ... | 1994 | 7918629 |
| heat shock response in the liver: expression and regulation of the hsp70 gene family and early response genes after in vivo hyperthermia. | heat shock response in cultured cells has been studied extensively; however few data are available on heat shock response in an intact organ of a living animal. in this study we analyzed the kinetics of expression of the heat shock protein 70 gene family (heat shock protein 70, heat shock cognate protein 73 and glucose-regulated protein 78) in the liver of the thermally stressed rat. new synthesis of heat shock protein 70 and heat shock cognate protein 73 was shown in liver slices pulse labeled ... | 1994 | 7927240 |
| l-type voltage-sensitive calcium channel activation stimulates gene expression by a serum response factor-dependent pathway. | a mechanism by which calcium-induced signals are transduced to the nucleus to activate transcription of the c-fos proto-oncogene has been characterized. the serum response element (sre), a region of the c-fos gene which controls growth factor-induced transcription, is now shown to mediate c-fos transcription in response to activation of l-type voltage-sensitive calcium channels. calcium-dependent transcriptional activation through the sre is mediated by the serum response factor (srf). membrane ... | 1994 | 7929249 |
| delta 9 acyl-lipid desaturases of cyanobacteria. molecular cloning and substrate specificities in terms of fatty acids, sn-positions, and polar head groups. | in cyanobacteria, the biosynthesis of unsaturated fatty acids is initiated by delta 9 acyl-lipid desaturase which introduces the first double bond at the delta 9 position of a saturated fatty acid that has been esterified to a glycerolipid. we have cloned genes, designated desc, for delta 9 acyl-lipid desaturases from two cyanobacteria, namely anabaena variabilis and synechocystis sp. pcc 6803. these desaturases, when expressed in escherichia coli, desaturated stearic acid to yield oleic acid at ... | 1994 | 7929259 |
| expression of a cdna for rat liver carnitine palmitoyltransferase i in yeast establishes that catalytic activity and malonyl-coa sensitivity reside in a single polypeptide. | a cdna encoding full-length carnitine palmitoyltransferase i (cpt i) from rat liver was expressed in saccharomyces cerevisiae, a system devoid of endogenous cpt activity. the recombinant enzyme was of the expected size (as deduced from immunoblots), membrane-bound, and detergent-labile. it was also potently inhibited by malonyl-coa, with an i50 value (concentration causing 50% inhibition) of approximately 5 microm, similar to that of the native enzyme in rat liver mitochondria. a truncated varia ... | 1994 | 7929364 |
| localization of sed5, a putative vesicle targeting molecule, to the cis-golgi network involves both its transmembrane and cytoplasmic domains. | the yeast sed5 protein, which is required for vesicular transport between er and golgi complex, is a membrane protein of the syntaxin family. these proteins are thought to provide the specific targets that are recognized by transport vesicles. we have investigated the mechanism by which sed5 protein is itself localized. expression of epitope-tagged versions of the yeast, drosophila and rat sed5 homologues in cos cells results in a perinuclear distribution; immuno-em reveals that the majority of ... | 1994 | 7929581 |
| the 80 kda cytosolic protein that binds the c-terminal part of rat acyl-coa oxidase is not a peroxisomal import receptor but a prolyl-endopeptidase. | in an attempt to identify putative peroxisomal import receptors, we investigated the cross-linking of a radioiodinated peptide consisting of the 13 last amino acids of acyl-coa oxidase and comprising the carboxy-terminal skl-peroxisomal targeting motive, to proteins present in different subcellular fractions from rat liver. the radiolabeled peptide could be cross-linked to an 80 kda protein present in the cytosol but not to proteins present in other subcellular fractions including highly purifie ... | 1994 | 7947927 |
| activation of alkylthioacrylic acids in subcellular fractions of rat tissues: a new spectrophotometric method for assay of acyl-coa synthetase. | alkylthioacrylic acids are activated by the long-chain acyl-coa synthetase in mitochondria and microsomes from rat liver, heart and kidney. the activation of a corresponding dicarboxylic acid was also demonstrated. the highest rate of activation was found in liver microsomes. the activation rate of the long-chain alkylthioacrylic acids is about one third of that of corresponding normal long-chain saturated fatty acids. the short-chain (methyl-, butyl-) thioacrylic acids showed no detectable acti ... | 1994 | 7948012 |
| signal transduction. switching off map kinases. | protein phosphatases have recently been identified that inactivate map kinases and turn off intracellular signalling pathways. their regulation may determine the response of cells to stimuli that signal via map kinases. | 1994 | 7953546 |
| cloning and sequencing of cdnas encoding the actin cross-linking protein transgelin defines a new family of actin-associated proteins. | we have used degenerate oligonucleotides, derived from the amino acid sequence of transgelin peptides [shapland et al., 1993: j. cell biol. 121:1065-1073], to isolate and sequence overlapping cdna clones encoding this actin gelling protein. primers with 5' restriction enzyme sites directed against the n and c terminal amino acids present in these clones were then used to amplify and clone the entire transgelin coding region from reverse transcribed rat small intestine cdna (rt-pcr). these studie ... | 1994 | 7954852 |
| characterization of a cytotoxic factor produced by rat bladder cancer cell line: its identity to tnf alpha. | clone c19 derived from a rat bladder cancer cell line bc31ad constitutively released cytotoxic factor rcf. the serum-free c19-conditioned medium was partially purified by deae-sephacel, sephacryl s-200 and monoq-fplc chromatographies to the specific activity of 6.4 x 10(6) u/mg protein (lm assay). rcf was a 17-kda protein with pi 4.6-5.0. anti-rcf serum neutralized the cytotoxic activity of rat and mouse, but not human, tumor necrosis factor-alpha (tnf alpha) as well as rcf. the partial amino ac ... | 1994 | 7959900 |
| comparison of human cap and cap2, homologs of the yeast adenylyl cyclase-associated proteins. | we previously reported the identification of human cap, a protein that is related to the saccharomyces cerevisiae and schizosaccharomyces pombe adenylyl cyclase-associated cap proteins. the two yeast cap proteins have similar functions: the n-terminal domains are required for the normal function of adenylyl cyclase, while loss of the c-terminal domains result in morphological and nutritional defects that are unrelated to the camp pathways. we have amplified and cloned cdnas from a human glioblas ... | 1994 | 7962207 |
| the srp54 gtpase is essential for protein export in the fission yeast schizosaccharomyces pombe. | signal recognition particle (srp) is a cytoplasmic ribonucleoprotein required for targeting a subset of presecretory proteins to the endoplasmic reticulum (er) membrane. here we report the results of a series of experiments to define the function of the schizosaccharomyces pombe homolog of the 54-kda subunit of mammalian srp. one-step gene disruption reveals that the srp54 protein, like srp rna, is essential for viability in s. pombe. precursor to the secretory protein acid phosphatase accumulat ... | 1994 | 7969124 |
| herbicide-resistant tobacco plants expressing the fused enzyme between rat cytochrome p4501a1 (cyp1a1) and yeast nadph-cytochrome p450 oxidoreductase. | transgenic tobacco (nicotiana tabacum cv xanthi) plants expressing a genetically engineered fused enzyme between rat cytochrome p4501a1 (cyp1a1) and yeast nadph-cytochrome p450 oxidoreductase were produced. the expression plasmid pgfc2 for the fused enzyme was constructed by insertion of the corresponding cdna into the expression vector png01 under the control of the cauliflower mosaic virus 35s promoter and nopaline synthase gene terminator. the fused enzyme cdna was integrated into tobacco gen ... | 1994 | 7972515 |
| heterologous expression of gamma e-crystallin produces protein with an aberrant tertiary structure. | expression of complete rat gamma e-crystallin cdna in saccheromyces cerevisiae and in escherichia coli at 25 degrees c produced soluble proteins similar to rat gamma e-crystallin but with an altered tertiary structure as judged by tryptophan fluorescence. expression of rat gamma e-crystallin cdna in e. coli at 37 degrees c produced insoluble inclusion bodies. refolding of denatured rat gamma e-crystallin from these inclusion bodies produced a protein similar to rat gamma e-crystallin but with al ... | 1994 | 7979386 |
| comparison of the effects of ca2+, adenine nucleotides and ph on the kinetic properties of mitochondrial nad(+)-isocitrate dehydrogenase and oxoglutarate dehydrogenase from the yeast saccharomyces cerevisiae and rat heart. | the regulatory properties of nad(+)-isocitrate dehydrogenase and oxoglutarate dehydrogenase in extracts of yeast and rat heart mitochondria were studied under identical conditions. yeast nad(+)-isocitrate dehydrogenase exhibits a low k0.5 for isocitrate and is activated by amp and adp, but is insensitive to atp and ca2+. in contrast, the rat heart nad(+)-isocitrate dehydrogenase was insensitive to amp, but was activated by adp and by ca2+ in the presence of adp or atp. both yeast and rat heart o ... | 1994 | 7980405 |
| identification of novel glutathione conjugates of disulfiram and diethyldithiocarbamate in rat bile by liquid chromatography-tandem mass spectrometry. evidence for metabolic activation of disulfiram in vivo. | recent studies have shown that the inhibitory effects of disulfiram and diethyldithiocarbamate (ddtc) (to which disulfiram is rapidly reduced in vivo) on the liver mitochondrial low-km form of aldehyde dehydrogenase (aldh) may be mediated by a reactive metabolite(s) of these compounds. in order to investigate the nature of such electrophilic intermediates in vivo, the present study was carried out with the goal of detecting and identifying their respective glutathione (gsh) conjugates in the bil ... | 1994 | 7981417 |
| activation of the eck receptor protein tyrosine kinase stimulates phosphatidylinositol 3-kinase activity. | the eph/eck subfamily of receptor protein tyrosine kinases is currently the largest subfamily of receptor protein tyrosine kinases with a dozen members (van der geer, p., hunter, t., and lindberg, r. a. (1994) annu. rev. cell biol. 10, 251-337). using the cytoplasmic domain of eck as bait in a yeast two-hybrid screen of mouse embryonic and t-cell cdna libraries, it was discovered that the p85 subunit of phosphatidylinositol 3-kinase bound eck. further, using glutathione s-transferase fusion prot ... | 1994 | 7982920 |
| purification to homogeneity of udp-glucose:glycoprotein glucosyltransferase from schizosaccharomyces pombe and apparent absence of the enzyme fro saccharomyces cerevisiae. | the udp-glc:glycoprotein glucosyltransferase was purified to homogeneity from the fission yeast schizosaccharomyces pombe. the enzyme has been recently suggested to be involved in the mechanism by which unfolded, partially folded, or misfolded glycoproteins are retained in the endoplasmic reticulum. the pure yeast glucosyltransferase formed protein-linked glc1-man9glcnac2,glc1man8glcnac2, and glc1man7glcnac2 when incubated with udp-glc and denatured thyroglobulin. the same compounds were formed ... | 1994 | 7982990 |
| the molecular evolution of g protein-coupled receptors: focus on 5-hydroxytryptamine receptors. | phylogenetic comparisons between homologous proteins can provide information on the rates of molecular evolution of the proteins. g protein-coupled receptors are a "superfamily" of proteins which exist in species ranging from yeast to man. based on an analysis of the percentage of amino acid homology between various species, the rate of molecular evolution of g protein-coupled receptors can be estimated at approx 1% per 10 million years. based on this assumption, the primordial 5-ht receptor mus ... | 1994 | 7984268 |
| the peroxisomal targeting signal of 3-oxoacyl-coa thiolase from saccharomyces cerevisiae. | all peroxisomal 3-oxoacyl-coa thiolases identified so far do not contain the previously identified tripeptide peroxisomal targeting signal at their carboxy-termini. for the two rat thiolases it was shown that their peroxisomal targeting signals are localized within the amino-terminal region of the proteins and are cleaved upon import. this report demonstrates that the n-terminal region of the peroxisomal 3-oxoacyl-coa thiolase from saccharomyces cerevisiae is essential for its peroxisomal target ... | 1994 | 7985420 |
| molecular cloning and functional expression of a cdna for mouse squalene synthase. | using a probe obtained by pcr amplification, a full-length cdna encoding squalene synthase was isolated from a mouse liver cdna library. its nucleotide sequence had an open reading frame fro a 416 amino acid polypeptide (calculated molecular mass, 48 kda). in vitro transcription of the cdna followed by in vitro translation produced a protein of the expected size. the deduced amino acid sequence was 93%, 88% and 46% identical to those of the rat, human and budding yeast squalene synthases, respec ... | 1995 | 7999794 |
| the yeast and mammalian ras pathways control transcription of heat shock genes independently of heat shock transcription factor. | yeast strains in which the ras-cyclic amp (camp) pathway is constitutively active are sensitive to heat shock, whereas mutants in which the activity of this pathway is low are hyperresistant to heat shock. to determine the molecular basis for these differences, we examined the transcriptional induction of heat shock genes in various yeast strains. activation of heat shock genes was attenuated in the strains in which the ras-camp pathway is constitutively active. in contrast, in a strain deficien ... | 1994 | 8007989 |
| cloning and expression of a human pro(tea)some beta-subunit cdna: a homologue of the yeast pre4-subunit essential for peptidylglutamyl-peptide hydrolase activity. | the cdna encoding a human prosome beta-subunit (hsbpros26) was isolated from a lymphoma library using the cdna of the xenopus homologue as a probe. the cdna contains an open reading frame encoding a protein of 233 amino acids and a calculated molecular weight of 25,909. comparison with interspecies homologues of hsbpros26 from xenopus (xlb), rat (rn3) and yeast (pre4) reveals a high degree of identity between the beta-subunits except for the n-terminal end, which is probably cleaved post-transla ... | 1994 | 8013624 |
| chemical and physiological effects of candida albicans toxin on tissues. | the prevalence of immunologically suppressed patients, including those infected with the aids virus, with cancer, and those having had transplant surgery to name a few, has provided an avenue for the rapid proliferation among these patients of the virulent yeast candida albicans. previous studies have determined that a potent toxin is produced by c. albicans which may cause extensive tissue damage. the extent of the tissue damage has never been determined, neither has the mechanism been explaine ... | 1994 | 8020249 |
| protein substitution in chloroplast ribosome evolution. a eukaryotic cytosolic protein has replaced its organelle homologue (l23) in spinach. | the chloroplast translational system differs from the eubacterial ones in containing several ribosomal proteins (rps) that have no apparent homologues in eubacteria, and in having their rp genes distributed in two cellular genome compartments. the genes maintained in the organelle genome encode mainly ribosome assembly proteins. the discovery in spinach and related plants (caryophyllidae) of a disrupted chloroplast gene encoding the ribosome assembly protein l23 raised speculations about the tra ... | 1994 | 8021938 |
| pharmacological profile of a new pyrrolizine derivative inhibiting the enzymes cyclo-oxygenase and 5-lipoxygenase. | 2,2-dimethyl-6-(4-chlorophenyl)-7-phenyl, 2,3-dihydro-1h-pyrrolizine-5-yl)-acetic acid (ml 3000) is a dual inhibitor of the enzymes cyclo-oxygenase and 5-lipoxygenase in bovine and human thrombocytes and granulocytes. in animal experiments the compound has antiphlogistic, analgesic, antipyretic, antiasthmatic and antiaggregative activity at a dosage that causes no gastrointestinal damage. | 1994 | 8024637 |
| the primary structure of rat ribosomal protein s23. | the amino acid sequence of the rat 40s ribosomal subunit protein s23 was deduced from the sequence of nucleotides in a recombinant cdna. ribosomal protein s23 has 142 amino acids, the nh2-terminal methionine is removed after translation of the mrna, and a molecular weight of 15,666. hybridization of the cdna to digests of nuclear dna suggests that there are 6 to 13 copies of the s23 gene. the mrna for the protein is about 650 nucleotides in length. rat s23 is identical to a human ribosomal prote ... | 1994 | 8037726 |
| effect of tumour progression on the androgenic regulation of the androgen receptor, trpm-2 and ypt1 genes in the shionogi carcinoma. | progression of an androgen-dependent tumour to an androgen-independent state is characterized by the loss of apoptotic potential, a property of cells which have differentiated under the influence of androgens. in an attempt to relate progression to mechanisms of apoptotic failure, we compared the relative levels of expression of androgen receptor and trpm-2 (clusterin) genes in androgen-dependent and -independent tumours derived from the shionogi carcinoma. the amount of 10 kb androgen receptor ... | 1994 | 8049130 |
| high affinity of ergopeptides for cytochromes p450 3a. importance of their peptide moiety for p450 recognition and hydroxylation of bromocriptine. | the interaction between rat and human liver cytochromes p450 with a series of lysergic acid derivatives and ergopeptide alkaloids was studied by difference visible spectroscopy. ergopeptides, like bromocriptine, ergocryptine and dihydroergotamine, strongly interacted with rat liver microsomes with the appearance of a difference spectrum which is characteristic of their binding to a protein site close to the heme. the intensity of this spectrum was clearly dependent on the amounts of p450s 3a in ... | 1994 | 8055971 |
| functional studies of e7 proteins from different hpv types. | we have performed comparative studies on the e7 proteins from malignant and non-malignant human papillomavirus types hpv 1, 6, 11, 16, 18, 33). gst/e7 fusion proteins from all these hpv types associate with rb1, p107 and the cyclin a/cdk2 complex. as has been shown for rb1, the association with p107 and cyclin a was weaker for the 'low risk' hpv6 and 11 e7 proteins as compared to 'high risk' hpv16, 18 and 33 e7 proteins. in contrast the e7 protein of the benign type hpv1 bound rb1, p107 and cycl ... | 1994 | 8058327 |
| cloning and sequence analysis of the rat augmenter of liver regeneration (alr) gene: expression of biologically active recombinant alr and demonstration of tissue distribution. | a full-length cdna clone encoding a purified augmenter of liver regeneration (alr) factor prepared from the cytosol of weanling rat livers was isolated. the 1.2-kb cdna included a 299-bp 5' untranslated region, a 375-bp coding region, and a 550-bp 3' untranslated region. it encoded a protein consisting of 125 amino acids. the molecular weight of alr calculated from the cdna was 15,081, which is consistent with the size estimated by sds/page under reducing conditions. the molecular weight of the ... | 1994 | 8058770 |
| a regulatory system for use in gene transfer. | we recently have demonstrated that a c-terminal deletion mutant of the human progesterone receptor (hprb891) fails to bind to progesterone but can bind ru 486 (mifepristone) and other progesterone antagonists. most significantly, this mutant receptor activates transcription of a reporter gene containing the progesterone response element in the presence of these antagonists. taking advantage of this finding and the modular nature of functional domains of steroid receptors, we constructed a chimer ... | 1994 | 8058776 |
| a single arabidopsis gf14 isoform possesses biochemical characteristics of diverse 14-3-3 homologues. | arabidopsis cdna clones of gf14 proteins originally were isolated on the basis of their association with the g-box dna/protein complex by a monoclonal antibody screening approach. gf14 proteins are homologous to the 14-3-3 family of mammalian proteins. here we demonstrate that recombinant gf14 omega, one member of the arabidopsis gf14 protein family, is a dimeric protein that possesses many of the attributes of diverse mammalian 14-3-3 homologues. gf14 omega activates rat brain tryptophan hydrox ... | 1994 | 8061318 |
| differential production of tnf by kupffer cells after phagocytosis of e. coli and c. albicans. | tumor necrosis factor (tnf) of hepatic origin is thought to play a pivotal role early in the genesis of the septic shock syndrome, regardless of microbial etiology. to determine if production of tnf by kupffer cells varies with microbial taxonomic class, we measured tnf secretory responses in primary cultures of rat kupffer cells to numerically equivalent gram-negative bacterial or fungal phagocytic challenges. after a 30-min exposure to media, latex beads, soluble escherichia coli lipopolysacch ... | 1994 | 8074222 |
| microtubular protein in its polymerized or nonpolymerized states differentially modulates in vitro and intracellular fluxes catalyzed by enzymes of carbon metabolism. | the fluxes through hk/g6pdh and pk/ldh coupled-enzymatic reactions were quantified in the presence of physiological concentrations (1-15 microm) of polymerized or non-polymerized microtubular protein (mtp) from rat brain and in a permeabilized yeast cell system. in vitro enzymatic fluxes were increased by either polymerized or nonpolymerized brain mtp mainly in the lower range of mtp concentration. at fixed mtp concentrations in the flux stimulatory range of hk/g6pdh (1 mg/ml mtp) or pk/ldh (0.4 ... | 1994 | 8083293 |
| homology between a human protein and a protein of the green garden pea. | in screening a rat mucosa cdna subtraction library, a clone that exhibited a remarkable degree of homology with a previously described cdna from the green garden pea, designated the 26g pea turgor protein, was found. a partial cdna sequence from rat and a complete cdna sequence from human were obtained. the deduced human protein had a molecular weight of 55,285 and was designated antiquitin because of its remarkable level of conservation through evolution. human antiquitin was 60% homologous to ... | 1994 | 8088832 |
| dna polymerase delta is required for base excision repair of dna methylation damage in saccharomyces cerevisiae. | we present evidence that dna polymerase delta of saccharomyces cerevisiae, an enzyme that is essential for viability and chromosomal replication, is also required for base excision repair of exogenous dna methylation damage. the large catalytic subunit of dna polymerase delta is encoded by the cdc2(pol3) gene. we find that the mutant allele cdc2-2 confers sensitivity to killing by methyl methanesulfonate (mms) but allows wild-type levels of uv survival. mms survival of haploid cdc2-2 strains is ... | 1994 | 8090767 |
| characterization of cathepsin b specificity by site-directed mutagenesis. importance of glu245 in the s2-p2 specificity for arginine and its role in transition state stabilization. | the ph dependence of cathepsin b-catalyzed hydrolyzes is very complex. at least seven dissociable groups are involved in the binding and hydrolysis of 7-amido-4-methyl coumarin and p-nitroaniline (pna)-based substrates containing a p1 arg and either a phe or arg at the p2 position. by site-directed mutagenesis we show that a previous suggestion, that arg202 is one of the groups which influences the ph dependence of cathepsin b-catalyzed hydrolysis of the z-arg-arg-pna substrate, is not valid. ho ... | 1993 | 8093241 |
| the cytochrome p450 1a2 active site: topology and perturbations caused by glutamic acid-318 and threonine-319 mutations. | phenyldiazene reacts with rat liver cyp1a2 expressed in saccharomyces cerevisiae to give a phenyl-iron complex that rearranges to a mixture (nb:na:nc:nd = 12:54:14:20, subscript indicates pyrrole ring) of n-phenyl-ppix (ppix = protoporphyrin) regioisomers. the same isomer pattern is obtained in each instance when the purified or microsomal enzyme reacts with phenyldiazene, indicating that the active site topology is not altered by removal of the protein from the membrane. reaction of the enzyme ... | 1993 | 8095402 |
| isolation and characterization of aap1. a gene encoding an alanine/arginine aminopeptidase in yeast. | the yeast aap1 gene, encoding a putative amino-peptidase, was isolated based on its ability to suppress the temperature-sensitive growth on nonfermentable carbon sources of spr5, a stationary phase regulatory mutant. aap1 was physically mapped to chromosome viii between put2 and cup1. sequence analysis of the aap1 gene showed a 1581-nucleotide open reading frame capable of encoding a 59-kilodalton protein. the protein encoded by this open reading frame exhibits approximately 40% sequence identit ... | 1993 | 8100228 |
| cloning and characterization of the gene that encodes acetyl-coenzyme a carboxylase in the alga cyclotella cryptica. | the gene that encodes acetyl-coenzyme a carboxylase (accase; ec 6.4.1.2) in the eukaryotic alga cyclotella cryptica has been isolated and cloned, representing the first time that a full-length gene for this enzyme has been isolated from a photosynthetic organism. the gene contains a 447-base pair intron that is located near the putative translation initiation codon and a 73-base pair intron that is located slightly upstream from the region that encodes the biotin binding site of the enzyme. the ... | 1993 | 8103514 |
| two genes for de novo purine nucleotide synthesis on human chromosome 4 are closely linked and divergently transcribed. | a cdna encoding human glutamine phosphoribosylpyrophosphate amidotransferase for step one in de novo purine nucleotide synthesis was cloned, sequenced, and expressed in chinese hamster ovary cells to yield functional enzyme. enzyme function was dependent upon removal of an 11-amino-acid propeptide. a mutant enzyme having three propeptide amino acid replacements was not processed and was not active. the human genes gpat, encoding the amidotransferase, and airc, encoding a bifunctional enzyme for ... | 1994 | 8106516 |
| a brain serine/threonine protein kinase activated by cdc42 and rac1. | a new brain serine/threonine protein kinase may be a target for the p21ras-related proteins cdc42 and rac1. the kinase sequence is related to that of the yeast protein ste20, implicated in pheromone-response pathways. the kinase complexes specifically with activated (gtp-bound) p21, inhibiting p21 gtpase activity and leading to kinase autophosphorylation and activation. autophosphorylated kinase has a decreased affinity for cdc42/rac, freeing the p21 for further stimulatory activities or downreg ... | 1994 | 8107774 |
| n-sec1: a neural-specific syntaxin-binding protein. | we have identified n-sec1, a rat brain homolog of the yeast sec1p protein that participates in the constitutive secretory pathway between the golgi apparatus and the plasma membrane. the rat brain cdna is predicted to encode a 68-kda protein with 65% amino acid identity to drosophila rop, 59% identity to caenorhabditis elegans unc-18, and 27% identity to saccharomyces cerevisiae sec1p. by rna blot analysis, n-sec1 mrna expression is neural-specific. an anti-peptide antiserum directed against the ... | 1994 | 8108429 |
| two novel deduced serine/threonine protein kinases from saccharomyces cerevisiae. | we have cloned genes for two closely related protein kinase (pk) homologues from saccharomyces cerevisiae. sequence alignment of the kinase domain with previously characterized pk reveals the highest degree of similarity with second messenger-regulated kinases. rck1 encodes a 58-kda protein, and is weakly expressed. rck2 encodes a 65-kda protein, and transcripts from this gene are readily detected. rck1 has been mapped to the l arm of chromosome vii, and rck2 to chromosome xii. disruption of the ... | 1994 | 8112585 |
| the influence of beta subunit structure on the stability of na+/k(+)-atpase complexes and interaction with k+. | heterologous expression of the beta subunit of h+/k(+)-atpase (hk beta) with alpha subunits of na+/k(+)-atpase (nk alpha) in yeast leads to the formation of ouabain binding complexes, indicating assembly of the two subunits into active ion pumps (eakle, k. a., kim, k. s., kabalin, m. a., and farley, r. a. (1992) proc. natl. acad. sci. u. s. a. 89, 2834-2838). complexes of nk alpha and hk beta are less sensitive to inhibition of ouabain binding by k+, suggesting that hk beta lowers the affinity o ... | 1994 | 8120007 |
| cloning of a rat cdna encoding dihydroxypolyprenylbenzoate methyltransferase by functional complementation of a saccharomyces cerevisiae mutant deficient in ubiquinone biosynthesis. | 3,4-dihydroxy-5-hexaprenylbenzoate methyltransferase (dhhb-mtase) is the product of the coq3 gene in saccharomyces cerevisiae and catalyses the fourth step in the biosynthesis of ubiquinone (coenzyme q) from p-hydroxybenzoic acid. a full-length cdna encoding a mammalian homologue of dhhb-mtase was isolated from a newly constructed rat testis cdna library by functional complementation of a coq3 deletion mutant of s. cerevisiae. the complementing clone contained a 1.1-kb poly(a)(+)-tailed insert w ... | 1994 | 8125303 |
| a gene homologous to that encoding udp galactose-4-epimerase is inducible by xylose in the yeast pachysolen tannophilus. | using dna sequencing, we have identified a fragment of genomic dna from pachysolen tannophilus that is homologous to the gal10 gene in yeasts and gale gene in bacteria, both encoding the udp galactose-4-epimerase (ec 5.1.3.2). this gene (designated ptgal10) is equally efficiently inducible by d-galactose (a hexose) and d-xylose (a pentose). the encoded protein shows the highest similarity to the homologous kluyveromyces lactis protein. this includes the n-terminal domain that is not present in h ... | 1994 | 8125329 |
| mutagenesis of the amino targeting signal of saccharomyces cerevisiae 3-ketoacyl-coa thiolase reveals conserved amino acids required for import into peroxisomes in vivo. | saccharomyces cerevisiae peroxisomal 3-ketoacyl-coa thiolase is a soluble matrix protein that does not end in a consensus peroxisomal targeting signal-1. the amino terminus of s. cerevisiae peroxisomal thiolase is conserved in 6 of 11 residues with the amino terminus of rat thiolase b, shown to act as a peroxisomal targeting signal-2 (swinkels, b.w., gould, s.j., bodnar, a.g., rachubinski, r.a., and subramani, s. (1991) embo j. 10, 3255-3262). unlike mammalian peroxisomal thiolases, there is no ... | 1994 | 8125978 |
| differential accumulation of a protein kinase homolog in trypanosoma brucei. | using degenerate oligonucleotide primers derived from conserved regions in the catalytic domains of protein kinases, we have identified transcripts of the protein kinase families in trypanosoma brucei by the polymerase chain reaction technique. from the cdnas synthesized from poly(a)+ rna purified from the bloodstream form of the pathogen, we have obtained seven distinct partial cdna sequences. deduced amino acid sequences of these seven clones contain conserved regions characteristic of catalyt ... | 1994 | 8126084 |
| a rat brain sec1 homologue related to rop and unc18 interacts with syntaxin. | sec1 is a hydrophilic protein that plays an essential role in exocytosis from the yeast saccharomyces cerevisiae. two high copy suppressors of mutations in the sec1 gene, sso1 and sso2, were recently identified that encode proteins of the syntaxin family. syntaxin (a t-snare), together with snap-25 and synaptobrevin/vamp (a t- and a v-snare, respectively), is thought to form the core of the docking-fusion complex in synaptic vesicle exocytosis. proteins that exhibit similarity to sec1 were ident ... | 1994 | 8134339 |
| a novel heparin-binding protein, hbp15, is identified as mammalian ribosomal protein l22. | a 15kda-protein (hbp15) was purified from mouse submandibular gland and bovine brain by virtue of its heparin-binding property. the amino acid sequences of mouse and bovine hbp15 showed a high degree of homology to a sea urchin protein encoded by gene called "development specific protein 217." using reverse transcription-polymerase chain reaction methods, cdna clones for hbp15 were isolated from submandibular gland mrna of mouse, human and pig, and sequenced. database search of hbp15 showed that ... | 1994 | 8135813 |
| chromosomal assignment of the human sa gene to 16p13.11 and demonstration of its expression in the kidney. | the sa gene is a novel gene of yet unknown function recently implicated in blood pressure regulation in rodent models of genetic hypertension. in this study we have located the human homologue of the sa gene to chromosome 16p13.11, by a combination of fluorescence in-situ hybridization and analysis of somatic cell hybrids carrying different segments of chromosome 16. this should facilitate investigation of its role in the genetic tendency to hypertension in humans. increased expression of the ge ... | 1994 | 8135833 |
| human, mouse, and rat calnexin cdna cloning: identification of potential calcium binding motifs and gene localization to human chromosome 5. | calnexin is a 90-kda integral membrane protein of the endoplasmic reticulum (er). calnexin binds ca2+ and may function as a chaperone in the transition of proteins from the er to the outer cellular membrane. we have purified human calnexin in association with the human interferon-gamma receptor and cloned calnexin cdna from placenta. fragments of calnexin have been prepared as glutathione s-transferase fusion proteins and analyzed for their abilities to bind 45ca2+ and ruthenium red. a subdomain ... | 1994 | 8136357 |
| pharmacokinetics and distribution of selenium in blood and organs of rats. | the dynamics of selenium concentration changes in blood, organs and tissues of rats after a single intragastric administration of selenium yeast and sodium selenite was determined. the course of selenium concentration changes in blood was described, the pharmacokinetic parameters were estimated according to the trivalent equation of dicompartment model and the selenium content in liver, kidneys, small intestine, spleen, heart, brain, stomach, testicles and prostate was determined 48 h after the ... | 1994 | 8140130 |
| inactivation of glyceraldehyde-3-phosphate dehydrogenase with sh-reagents and its relationship to the protein quaternary structure. | inactivation of mung bean glyceraldehyde-3-phosphate dehydrogenase (gpdh) with excess iodoacetate or n-ethylmaleimide exhibits pseudo-first order kinetics at ph 7.3 and 8.6 in the absence and presence of nad+, suggesting that all the reactive sh groups (four per tetrameric gpdh molecule) have equivalent reactivity towards these reagents. this is similar to the d2-symmetry conformation proposed on the basis of thermal inactivation data [malhotra and srinivasan, arch. biochem. biophys. 236, 775-78 ... | 1993 | 8144169 |
| sequencing and functional analysis of a 32,560 bp segment on the left arm of yeast chromosome ii. identification of 26 open reading frames, including the kip1 and sec17 genes. | we report here the dna sequence of a segment (alpha 1006.13: yblo5) of chromosome ii of saccharomyces cerevisiae, extending over 32.5 kb. the segment contains 26 open reading frames (orfs) from yblo501 to yblo526. ybl0505 corresponds to the sec17 gene and ybl0521 to the kip1 gene. ybl0516 contains an intron, ybl0513 shows homology with the rat protein phosphatase and ybl0526 contains a zinc-finger motif. disruption of 14 genes by insertion of a ura3 cassette has been performed and these mutants ... | 1993 | 8154187 |
| cdc25a is a novel phosphatase functioning early in the cell cycle. | the cdc25+ tyrosine phosphatase is a key mitotic inducer of the fission yeast schizosaccharomyces pombe, controlling the timing of the initiation of mitosis. mammals contain at least three cdc25+ homologues called cdc25a, cdc25b and cdc25c. in this study we investigate the biological function of cdc25a. although very potent in rescuing the s.pombe cdc25 mutant, cdc25a is less structurally related to the s.pombe enzyme. northern and western blotting detection reveals that unlike cdc25b, cdc25c an ... | 1994 | 8156993 |
| cloning and characterization of an evolutionarily divergent dna-binding subunit of mammalian tfiiic. | transcription factor iiic (tfiiic) is required for the assembly of a preinitiation complex on 5s rna, trna, and adenovirus va rna genes and contains two separable components, tfiiic1 and tfiiic2. tfiiic2 binds to the 3' end of the internal control region of the vai rna gene and contains five polypeptides ranging in size from 63 to 220 kda; the largest of these directly contacts dna. here we describe the cloning of cdnas encoding all (rat) or part (human) of the 220-kda subunit (tfiiic alpha). su ... | 1994 | 8164661 |
| functional properties of non-muscle tropomyosin isoforms. | tropomyosins are a family of actin filament binding proteins. they have been identified in many organisms, including yeast, nematodes, drosophila, birds and mammals. in metazoans, different forms of tropomyosin are characteristic of specific cell types. most non-muscle cells, such as fibroblasts, express five to eight isoforms of tropomyosins. the various isoforms exhibit distinct biochemical properties that appear to be required for specific cellular functions. | 1994 | 8167032 |
| a sequence related to a dna recognition element is essential for the inhibition by nucleotides of proton transport through the mitochondrial uncoupling protein. | the uncoupling protein (ucp) is uniquely expressed in brown adipose tissue, which is a thermogenic organ of mammals. the ucp uncouples mitochondrial respiration from atp production by introducing a proton conducting pathway through the mitochondrial inner membrane. the activity of the ucp is regulated: nucleotide binding to the ucp inhibits proton conductance whereas free fatty acids increase it. the similarities between the ucp, the adp/atp carrier and the dna recognition element found in the d ... | 1994 | 8168495 |
| the significance of denaturant titrations of protein stability: a comparison of rat and baker's yeast cytochrome c and their site-directed asparagine-52-to-isoleucine mutants. | the residue asparagine-52 of rat cytochrome c and baker's yeast iso-1-cytochrome c was mutated to isoleucine by site-directed mutagenesis, and the unfolding of the wild-type and mutant proteins in urea or guanidinium chloride solutions was studied. whereas the yeast mutant cytochrome unfolded in 4-7 m urea with a rate constant (k) of 1.7 x 10(-2) s-1, the rat mutant protein unfolded with k = 5.0 x 10(-2) s-1, followed by a slow partial refolding with k = 5.0 x 10(-4) s-1. denaturant titrations i ... | 1994 | 8172593 |
| the endogenous cyclic amp antagonist, cyclic pip: its ubiquity, hormone-stimulated synthesis and identification as prostaglandylinositol cyclic phosphate. | this report shows that the cyclic amp antagonist cyclic pip is present in all organs and tissues of the rat so far examined: brain, heart, lung, intestine, kidney, liver, spleen, skeletal muscle and fat. the synthesis of cyclic pip is stimulated by insulin or noradrenaline (alpha-adrenergic action) in a dose-dependent fashion. increasing cyclic pip synthesis with increasing insulin concentrations matches the insulin receptor binding curves. cyclic pip levels in blood serum remain low after hormo ... | 1993 | 8180414 |
| sequence of rat mitochondrial glycerol-3-phosphate dehydrogenase cdna. evidence for ef-hand calcium-binding domains. | the fad-dependent, mitochondrial glycerol-3-phosphate dehydrogenase (ec 1.1.99.5) is an essential component of the glycerol phosphate shuttle and is abundant in the pancreatic insulin cell, skeletal muscle, and brain. although dna clones for this enzyme and its homologues have been isolated from bacteria and yeast, it has never been cloned from a higher eukaryote. we have cloned and sequenced cdnas encoding the rat mitochondrial glycerol-3-phosphate dehydrogenase. the longest cdna (2337 base pai ... | 1994 | 8182039 |
| rna- and single-stranded dna-binding (ssb) proteins expressed during drosophila melanogaster oogenesis: a homolog of bacterial and eukaryotic mitochondrial ssbs. | little is known about the identity and involvement of single-stranded (ss) dna-binding (ssb) and rna-binding proteins in developmental processes that occur during oogenesis in drosophila melanogaster (dm). here, we describe a molecular approach designed to identify such proteins by virtue of their ssdna-binding activity. we have constructed a directional ovarian cdna library and conducted expression cloning screens which identified five unique cdnas that encode proteins capable of binding ssdna. ... | 1994 | 8206370 |
| rheb, a growth factor- and synaptic activity-regulated gene, encodes a novel ras-related protein. | neuronal activity results in long term cellular changes that underlie normal brain development and synaptic plasticity. to examine the molecular basis of activity-dependent plasticity, we have used differential cloning techniques to identify genes that are rapidly induced in brain neurons by synaptic activity. here we describe an inducible novel member of the ras family of small gtp-binding proteins we have termed rheb. rheb mrna is rapidly and transiently induced in hippocampal granule cells by ... | 1994 | 8206940 |
| peroxisomal proliferators inhibit acyl coa synthetase and stimulate protein kinase c in vivo. | the mechanism by which hypolipidemic drugs and industrial plasticizers cause hepatic tumors in rodents remains unknown. it is known, however, that protein kinase c is elevated during hepatic cell turnover, and sustained cellular replication is correlated with an increased incidence of hepatic tumors. therefore, several peroxisomal proliferators varying in their tumorigenic potency in chronic feeding studies were examined for their ability to increase protein kinase c activity. intragastric admin ... | 1994 | 8209376 |
| antioxidant defenses of baker's yeast against free radicals and lipid peroxides in rat brain. | we examined through the electron spin resonance spectrometry/spin trapping technique the antioxidant activity of baker's yeast saccharomyces cerevisiae which is known to have both enzymatic and nonenzymatic antioxidants. the components in baker's yeast were separated by differential filtration/centrifugation using centrifuge-type filter tubes, yielding four nonenzymatic thermostable fractions of varied molecular weights which scavenged 85-95% of 1,1-diphenyl-2-picrylhydrazyl in organic solution, ... | 1993 | 8215398 |
| cloning and functional expression of a schistosoma japonicum cdna homologous to the enolase gene family. | a cdna encoding the complete open reading frame of schistosoma japonicum enolase has been cloned. the 1494bp cdna (c30) was isolated from a s. japonicum cdna expression library immunoscreened with hyperimmune rabbit sera raised against soluble adult s. japonicum proteins. the orf encodes a protein of 434 amino acids exhibiting 72% identity to human, murine, and rat enolases, and 62% identity to saccharomyces cerevisiae enolase. the inferred molecular mass of the protein is 47,251 daltons, simila ... | 1993 | 8216251 |
| the primary structure of two proteins from the large ribosomal subunit of rice. | we isolated two rice cdnas which encode an open reading frame of 389 amino acids. their deduced amino acid sequence corresponded to the ribosomal protein (r-protein). a comparison of amino acid sequence shows that the deduced amino acid sequence of one cdna is homologous to arabidopsis, yeast and the rat r-protein l3. another encoded products with a high degree of homology to the rat r-protein l7a and yeast r-protein l4. | 1993 | 8218398 |
| dcp gene of escherichia coli: cloning, sequencing, transcript mapping, and characterization of the gene product. | dipeptidyl carboxypeptidase is a c-terminal exopeptidase of escherichia coli. we have isolated the respective gene, dcp, from a low-copy-number plasmid library by its ability to complement a dcp mutation preventing the utilization of the unique substrate n-benzoyl-l-glycyl-l-histidyl-l-leucine. sequence analysis of a 2.9-kb dna fragment revealed an open reading frame of 2,043 nucleotides which was assigned to the dcp gene by n-terminal amino acid sequencing and electrophoretic molecular mass det ... | 1993 | 8226676 |
| molecular cloning and cellular localization of a bip homologue in trypanosoma brucei. divergent er retention signals in a lower eukaryote. | using the polymerase chain reaction with degenerate primers, three new members of the hsp70 gene family of trypanosoma brucei have been identified. a genomic clone of one of these, ga, has been fully sequenced and the corresponding gene product has been characterized using antibody to recombinant ga fusion protein. ga is the trypanosomal homologue of bip, an endoplasmic reticulum resident hsp70 gene family member, based on four lines of evidence: (1) ga protein has 64% deduced amino acid identit ... | 1993 | 8227199 |
| bay x1005, a new inhibitor of leukotriene synthesis: in vivo inflammation pharmacology and pharmacokinetics. | (r)-2-[4-(quinolin-2-yl-methoxy)phenyl]-2-cyclopentyl acetic acid) (bay x1005) is an orally active inhibitor of the synthesis of the leukotrienes b4 and c4 in selected animal models that effectively reduces the vascular phenomena of inflammation, i.e., edema formation and leukocyte immigration. the arachidonic acid-induced mouse ear inflammation test allowed the evaluation of the antiedematous effects of bay x1005 after topical (ed50, 18 micrograms/ear) and oral (ed50, 48.7 mg/kg) administration ... | 1993 | 8229782 |