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H Teraoka

Publications and source records attributed to H Teraoka.

At least 73 records · Page 4Linked to original sources
PubMed1994

Purification, characterization, primary structure, crystallization and preliminary crystallographic study of a serine proteinase from Streptomyces fradiae ATCC 14544.

A proteinase having wide substrate specificity was isolated from Streptomyces fradiae ATCC 14544. This proteinase, which we propose to call SFase-2, was purified from the culture filtrate by S-Sepharose chromatography. The purified enzyme showed an apparent molecular mass of 19 kDa on SDS/PAGE. When synthetic peptides were used as substrates, SFase-2 showed broad substrate specificity. It also hydrolyzed keratin, elastin and collagen as proteinaceous substrates. It was completely inhibited by diisopropylfluorophosphate and chymostatin, but not by tosylphenylalaninechloromethane, tosyllysinechloromethane or EDTA, indicating that it can be classified as a serine proteinase. The matured protein sequence of SFase-2 was determined by a combination of amino acid sequencing and the DNA sequencing of the gene. SFase-2, consisting of 191 amino acids, is a novel proteinase. It showed 76% similarity in the amino acid sequence with Streptomyces griseus proteinase A [Johnson P. and Smillie L. B. (1974) FEBS Lett. 47, 1-6]. For insight into the three-dimensional structure of SFase-2, we obtained single crystals by the vapor diffusion method using sodium phosphate as a precipitant. These crystals belonged to the orthorhombic, space group P2(1)2(1)2(1) with cell dimensions a = 6.92 nm, b = 7.28 nm, c = 2.99 nm; one molecule was present in the asymmetric unit.

Amino Acid Sequence↗
PubMed1994

Muscle layer and regional differences in autonomic innervation and responsiveness to transmitter agents in swine myometrium.

1. To clarify possible regional and muscle layer differences in adrenergic innervation of swine myometrium, functional, biochemical and histochemical experiments were performed on longitudinal (LM) and circular (CM) muscle isolated from non-pregnant uteri of 84 gilts. 2. Transmural stimulation (TMS) in the presence of propranolol evoked tetrodotoxin-sensitive contractions in a frequency-dependent manner (2-20 Hz) in LM and CM. The cornual LM contractions were attenuated by phentolamine (1 microM) and by guanethidine (10 microM) though unaffected by atropine (1 microM). Contractions in cervical LM were diminished by atropine but not by phentolamine, and the corpus LM contractions were reduced incrementally by atropine and phentolamine when added sequentially. In CM, the TMS-induced contractions were abolished by tetrodotoxin and atropine in all three regions. 3. In response to noradrenaline (NA) and acetylcholine (ACh), LM contractile intensity was the most potent in cornua, slightly weaker in the corpus and weakest in the cervix. CM was insensitive to NA, and contractile responses elicited by ACh indicated no regional variation. 4. NA content, significantly greater in LM than in CM, was most highly concentrated in cornual LM. Nerves exhibiting glyoxylic acid-induced histofluorescence occurred in both LM and CM, though more abundantly in LM and with notable density in the cornual LM. Cholinesterase activity, distributed evenly throughout the three myometrial regions studied, was more intense in LM than in CM. 5. These results show that, in swine myometrium, innervation in cornual LM is predominantly noradrenergic, cervical LM is mostly cholinergic, and throughout the myometrium the CM layers are principally cholinergic.

Acetylcholine↗
PubMed1994

Inhibitory effects of caffeine on secretagogue-induced catecholamine secretion from adrenal chromaffin cells of the guinea-pig.

1. The inhibitory action of caffeine on catecholamine secretion induced by secretagogues was investigated in perfused adrenal glands and dispersed chromaffin cells of the guinea-pig. 2. Caffeine (10 mM) caused a reversible inhibition of catecholamine secretion evoked by acetylcholine (ACh, 50 microM), KCl (56 mM, high K+) and veratridine (100 microM) and that induced by muscarinic receptor activation in the absence of extracellular Ca2+ in perfused adrenal glands. 3. In dispersed chromaffin cells, caffeine caused a dose-dependent inhibition of the secretory responses to 100 microM ACh and veratridine. Forskolin (30 microM), dibutyryl cyclic AMP (1 mM) and 8-bromo cyclic AMP (1 mM) did not mimic the action of caffeine. 4. In the voltage-clamp, whole-cell recording mode (at a holding potential of -60 mV or -70 mV), ACh (100 microM) evoked an inward current, and depolarizing pulses elicited inward Na+, Ca2+ and outward K+ currents. All these responses were partially inhibited by caffeine (20 mM). 5. ACh rapidly increased the intracellular concentration of Ca2+ ([Ca2+]i) in fura-2-loaded cells in either the presence or the absence of external Ca2+, though its magnitude was decreased by about 50% in Ca(2+)-free conditions. Caffeine (20 mM) inhibited these ACh-induced increases in [Ca2+]i. 6. In permeabilized chromaffin cells, caffeine (20 mM) caused an inhibition of catecholamine secretion evoked by Ca2+ (10 microM). 7. These results suggest that caffeine inhibits evoked catecholamine secretion through mechanisms such as the blockade of voltage-dependent Na+ and Ca2+ currents and ACh receptor current, and reduction of the release of intracellularly stored Ca2+ and/or Ca(2+)-sensitivity of the secretory apparatus.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed1994

Release from G0/G1 arrest induced by dimethyl sulfoxide in human lymphoid cells: regulation of synthesis and activation of the p33cdk2 and p34cdc2 kinases.

Raji cells, a human Burkitt's lymphoma-derived cell line, will accumulate in a G0-like state upon prolonged (5-6 days) incubation in medium containing 1.5% dimethyl sulfoxide (DMSO). After removal of DMSO, the cells reenter the cell cycle in a synchronous manner and proliferate. After 5.5 days incubation in DMSO, S phase entry occurs at about 21-24 h after release, which is about the length of the first G1 phase of normal human lymphocytes which are stimulated in vitro to enter the cell cycle. The G0-like state of arrested cells and the sequence of events occurring after release from DMSO mimic, in most ways studied, those of normal lymphocytes. Arrested Raji cells lack many cell cycle-regulated molecules, including cyclin A, proliferating cell nuclear antigen, and the p34cdc2 kinase. They contain only hypophosphorylated p110Rb and a low level of enzymatically inactive p33cdk2 kinase. After reentering the cell cycle, a series of events occurred, including phosphorylation of p110Rb and accumulation of the cyclin A and proliferating cell nuclear antigen proteins in mid-G1 and the accumulation of the p33cdk2 and p34cdc2 proteins beginning in late G1, just prior to S-phase entry. Cyclin E levels in Raji cells appeared to be less regulated than in normal cells, with high levels of this protein being present in resting cells and throughout the entire cell cycle. The time courses of activation of the p34cdc2 and p33cdk2 kinases were similar; both became detectable at about 21 h after release and increased greatly in early S.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetyltransferases↗
PubMed1993

Expression of active human DNA ligase I in Escherichia coli cells that harbor a full-length DNA ligase I cDNA construct.

A recombinant plasmid for expression of full-length human DNA ligase I (phLig-I) was constructed in a plasmid/phage chimeric vector, pTD-T7N, which was derived from pUC118 by oligonucleotide-directed mutagenesis. The insert contained a 2757-base pair coding sequence for a whole human DNA ligase I and an extra ACC codon adjacent to the ATG initiation codon. This ACC codon was required for achieving high levels of expression of full-length DNA ligase I in Escherichia coli strain BL21. The recombinant plasmid, which was designed to exploit the T7 late promoter and the ATG initiation codon for beta-galactosidase was transfected into E. coli BL21 cells that express T7 RNA polymerase. The recombinant clone produced relatively high levels of DNA ligase I with a molecular mass of 130 kDa, as estimated by SDS-polyacrylamide gel electrophoresis. The DNA ligase was purified to near-homogeneity by the two-step column chromatographic procedure from BLphLig-I cells that had been induced with isopropyl beta-D-thiogalactoside. The specific activity, chromatographic behavior, kinetic properties, molecular mass, and antigenicity of the recombinant human DNA ligase I were indistinguishable from those of purified mammalian DNA ligase I. Metabolically labeling experiments with 32P(i) indicate that the recombinant DNA ligase I was present as an enzyme-AMP reaction intermediate, but not as a phosphoprotein, in the E. coli cells.

Amino Acid Sequence↗
PubMed1993

Structure, chromosomal localization, and expression of mouse reg genes, reg I and reg II. A novel type of reg gene, reg II, exists in the mouse genome.

We previously identified a gene, reg (i.e. regenerating gene), in the screening of a regenerating islet-derived cDNA library of rat (Terazono, K., Yamamoto, H., Takasawa, S., Shiga, K., Yonemura, Y., Tochino, Y., and Okamoto, H. (1988) J. Biol. Chem. 263, 2111-2114), and isolated a human reg cDNA and gene (Watanabe, T., Yonekura, H., Terazono, K., Yamamoto, H., and Okamoto, H. (1990) J. Biol. Chem. 265, 7432-7439); the rat and human cDNAs encode 165- and 166-amino acid proteins, respectively. Until now, it was thought that there is a single locus for Reg protein in the mammalian genome. In this study, we isolated two distinct cDNAs and genes, one of which was a mouse homologue to rat and human reg gene, the other a novel type of reg gene. We designated them reg I and reg II, respectively. The two proteins encoded by these genes share 76% amino acid sequence identity with each other. Both genes span about 3 kilobase pairs, and the genomic organization of six exons and five introns is conserved between them. Chromosomal mapping studies indicate that the reg I gene is localized on mouse chromosome 12, whereas the reg II gene is localized on chromosome 3. By Northern blot analysis, both reg I and reg II mRNAs are detected in the normal pancreas and hyperplastic islets of aurothioglucose-treated mice, but not in the normal islets. It is remarkable that in the gallbladder reg I is expressed, but reg II is not.

Amino Acid Sequence↗
PubMed1993

Receptor-binding capability of pancreatic phospholipase A2 is separable from its enzymatic activity.

Mammalian pancreatic phospholipase A2 (PLA2-I) has its specific receptor through which PLA2-I induces a variety of biological responses. In this study, a fundamental relationship between the enzymatic and the receptor-binding activities of PLA2-I was investigated. The specific binding of PLA2-I to the receptor was found to be independent of Ca2+ which is requisite for the PLA2 activity. On the basis of this observation, we designed and produced mutant PLA2-Is without Ca(2+)-binding abilities in order to demonstrate that the structural requirement for the enzymatic activity of PLA2-I is not identical with that for its receptor-binding reaction. These mutant PLA2-Is lost almost all enzymatic activity through a disturbance at the Ca(2+)-binding site, as expected, but still retained a substantial affinity to the receptor, allowing us to conclude that the receptor-binding reaction of PLA2-I is separable from its catalytic action.

Animals↗
PubMed1993

Detection of human T cell receptor cDNAs (alpha, beta, gamma and delta) by ligation of a universal adaptor to variable region.

The study of T cell receptor (TCR) genes has been hampered by their large repertoires and elusive methods for gene amplification. We have developed a new method for amplification of all human TCR genes (alpha, beta, gamma, and delta) with the ligation of a universal adaptor to the leader sequence of variable (V) regions, which permitted effective and reproducible amplification of all four types of TCR genes. cDNA sequencing of TCR-gamma, -delta, -alpha, -beta was carried out in respectively 15, 13, 28, and 26 T cell clones from human peripheral blood T cells using a newly developed universal adaptor and these methods. TCR-gamma V-II (V gamma 9) was a major population, and V-I (V gamma 2 and 3) and V-III (V gamma 10) were next major populations among TCR-gamma subfamilies, and confirmed the previous observations determined using mAbs specific to TCR-gamma. All five clones of TCR-gamma V-II and three of five clones of TCR-gamma V-I subfamilies had in-frame V-N-J junctions. In contrast, sequences from both TCR-gamma V-III (4/4 clones) and V-IV (1/1 clones) subfamilies had intron-like regions that caused out-of-frame cDNA, suggesting that most of TCR-gamma V-III and V-IV in PBL are not functional. V delta 2 was a major population and V delta 1 was a next predominant population among TCR-delta subfamilies, also confirming the previous observations determined using mAbs to TCR-delta. With regards to TCR-alpha and -beta, this new method randomly amplified TCR cDNAs. In addition, the sequences of 5' portions of three TCR-V-alpha and one TCR-V beta were extended. Two new TCR-alpha subfamilies and one new TCR-beta family were also identified. In summary, this new method will provide a scientific tool for understanding structures of the human TCR genes involved in specific immune responses.

Amino Acid Sequence↗
PubMed1993

Neurofilament deficiency in quail caused by nonsense mutation in neurofilament-L gene.

The existence of a neurofilament-deficient mutant of Japanese quail was recently documented (Yamasaki, H., C. Itakura, and M. Mizutani. 1991. Acta Neuropathol. 82:427-434), but the genetic events leading to the neurofilament deficiency have yet to be determined. Our molecular biological analyses revealed that the expression of neurofilament-L (NF-L) gene was specifically repressed in neurons of this mutant. To search for mutation(s) responsible for the shutdown of this gene expression, we cloned and sequenced the NF-L genes in the wild-type and mutant quails. It is eventually found that the NF-L gene in the mutant includes a nonsense mutation at the deduced amino acid residue 114, indicating that the mutant is incapable of producing even a trace amount of polymerization-competent NF-L protein at any situation. The identification of this nonsense mutation provides us with a solid basis on which molecular mechanisms underlying the alteration in the neuronal cytoskeletal architecture in the mutant should be interpreted.

Amino Acid Sequence↗
PubMed1993

Difference in the effectiveness of Ca2+ to evoke catecholamine secretion between adrenaline- and noradrenaline-containing cells of bovine adrenal medulla.

Differential adrenaline (Ad) and noradrenaline (NA) secretions evoked by secretagogues were investigated using digitonin-permeabilized adrenal chromaffin cells, cultured adrenal chromaffin cells, and perfused adrenal glands of the ox. In digitonin-permeabilized cells, Ca2+ (0.8-160 microM) caused a concentration-dependent increase in catecholamine secretion, which was characterized by a predominance of NA over Ad secretion. Acetylcholine (10-1,000 microM), high K+ (14-56 mM), and bradykinin (0.1-1,000 nM) all were confirmed to induce the release of more NA than Ad at all concentrations used. There was no apparent difference in the ratios of NA/Ad between Ca(2+)-induced catecholamine secretion from digitonin-permeabilized cells and those induced by secretagogues from cultured cells. Qualitatively the same result was obtained in the secretory responses to acetylcholine and high K+ in perfused adrenal glands. These results indicate that the effectiveness of Ca2+ for catecholamine secretion is higher in the secretory apparatus of NA cells than in that of Ad cells of the bovine adrenal medulla. This may be one of the reasons why the secretagogues cause a predominance of NA secretion over Ad secretion in the bovine adrenal medulla.

Adrenal Medulla↗
PubMed1993

Thymic stroma-derived T-cell inhibitory factor (TSTIF) 1. TSTIF induces inhibition of antigen-stimulated T-cell proliferation.

The present study investigates the capacity of the MRL104.8a thymic stromal cell clone to modulate T-cell growth. The culture supernatant (SN) from the MRL104.8a stromal cell monolayer was added to cultures of Th-clones with or without T-cell receptor (TCR) stimulation as provided by antigen (Ag) plus splenic antigen-presenting cells (APC). The results demonstrated that the MRL104.8a SN containing IL-7 activity induced dose-dependent proliferation of Th cells when they were not stimulated with Ag/APC. In contrast, addition of the same SN to cultures of Th cells during stimulation with Ag/APC resulted in potent dose-dependent inhibition of their proliferation. IL-7 contained in the SN was neither responsible for, nor involved in the inhibition event, because the inhibition was not observed with rIL-7 and was not neutralized by anti-IL-7 antibody. The growth inhibition of the Th clone in the presence of Ag plus APC was also induced by IL-10 or TGF-beta. However, the MRL104.8a SN-induced growth inhibition was mediated by a factor distinct from these cytokines, because (1) IL-10 cDNA was not amplified in polymerase chain reaction (PCR) products derived from MRL104.8a cells; (2) TGF-beta cDNA was detected in the PCR products, but only marginal levels of TGF-beta activity in an active form were found in the MRL104.8a SN and the SN-induced inhibition was not prevented by anti-TGF-beta antibody; and (3) addition of rIL-7 to antigen-stimulated cultures containing rTGF-beta or rIL-10 induced IL-7 mediated Th proliferation, whereas the MRL104.8a SN-induced inhibition was still observed in the presence of excess rIL-7. Moreover, this factor, designated thymic stroma-derived T-cell inhibitory factor, was found to have a m.w. of 20-25 x 10(3) and to exhibit heparin-binding property. Thus, these results indicate that the MRL104.8a thymic stromal cell clone produces a potentially novel factor that induces inhibition of antigen-stimulated T-cell proliferation.

Animals↗
PubMed1993

Arachidonic acid metabolism in cells transfected with sense and anti-sense cDNA to annexin I.

Thymic epithelial cell line TEA3A1 produce prostaglandin E2 (PGE2) and express high levels of annexin I. In order to study the relationship between the levels of annexin I expression and the arachidonic acid metabolism, TEA3A1 cells transfected with expression vector containing full length annexin I cDNA in either sense or anti-sense orientation was studied. In the anti-sense cells where the level of annexin I was reduced, the PGE2 production was significantly lower. On the other hand, PGE2 production was significantly higher in sense cells where the production of annexin I was also higher than in control cells. Our results show that increased PGE2 production in sense cells was accompanied by higher levels of PLA2 enzymatic activities. These results suggest that the production of annexin I is positively associated with the phospholipase A2 enzymatic activity and the prostaglandin production in thymic epithelial cells.

Animals↗
PubMed1993

[Investigations on the quality of well water in the Sakata-Akumi areas of Yamagata-ken].

Samples of well-waters were collected from 1988 through 1992 from 40 shallow wells (non-confined ground water), with samples taken from the well at 16 m depth from the ground surface up to the bottom of the well. Wells were located in the Sakata Akumi area of Yamagata-ken. The water quality was analyzed for 29 items and the results are as follows: 1) In the rural area on the coast of the Sea of Japan, the soil consists of sand, mud and gravel, and dry field farming with cultivation of fruit and vegetables is carried on. Concentrations of nitrate and nitrite nitrogen (NO2+3-N) in the well waters (n = 12) in this area were found to be in the range of 2.3-19 mg/l with the average of 8.2 mg/l, probably mainly derived from agriculture. On the other hand, in the rural area where the indigenous rock consists mainly of andesite and basalt and where rice crops are cultivated, the concentrations of NO2+3-N in the well water (n = 21) were found in the range of 0.15-2.9 mg/l with the average of 0.69 mg/l. 2) The concentrations of NO2+3-N were analyzed monthly for a total of 20 times between 1991 to 1992, from the Sea of Japan coastal region where the highest average of 19 mg/l from all samples was obtained. Analysis shows that a remarkable seasonal variation exists, with a range of 25-33 mg/l seen in both April and May during the two years observation, but only 14-17 mg/l in other months.(ABSTRACT TRUNCATED AT 250 WORDS)

Japan↗
PubMed1992

Role of colony-stimulating factor-1 in macrophage activation in tumor-bearing mice.

We previously reported a dramatically increased number of macrophages in tumor-bearing mice. In this study, we investigated the involvement of CSF in that phenomenon. CSF-1 responding cells as macrophages precursors increased significantly in number in the spleens of tumor-bearing mice as compared with those in normal mice. Splenic cells and sera from the tumor-bearing mice respectively expressed CSF-1 in mRNA and serum protein levels, but failed to express the other CSF (granulocyte-macrophage-CSF or IL-3). Nonadherent splenic mononuclear cells (< 0.5% macrophages) from normal mice proliferated and differentiated into mature macrophages in culture within 7 days with recombinant mouse CSF-1 (rCSF-1). Both macrophages harvested from tumor-bearing mice and those activated in vitro with rCSF-1 expressed mostly Mac-1, -2 (and -3) Ag, showed yeast phagocytosis, produced IL-1 but not IL-2 or IL-3, and displayed potent cytotoxicity against NK cell resistant Meth-A tumor cells. These macrophages also expressed lipocortin I mRNA and secreted lipocortin I protein, and suppressed mitogenic responses of splenic lymphocytes. rCSF-1-activated macrophages derived from nonadherent splenic cells expressed both CSF-1 and CSF-1 receptor (c-fms) mRNA. Administration of rCSF-1 into normal mice induced hemopoietic and immunologic alternations similar to those observed in tumor-bearing mice. These results suggest that CSF-1 is involved in the dramatic increase of macrophages in tumor-bearing mice, possibly through an autocrine or paracrine loop.

Animals↗
PubMed1992

Purification, characterization, cloning, and expression of a glutamic acid-specific protease from Bacillus licheniformis ATCC 14580.

A glutamic acid-specific protease has been purified to homogeneity from Bacillus licheniformis ATCC 14580 utilizing Phe-Leu-D-Glu-OMe-Sepharose affinity chromatography and crystallized. The molecular weight of the protease was estimated to be approximately 25,000 by SDS-polyacrylamide gel electrophoresis. This protease, which we propose to call BLase (glutamic acid-specific protease from B. licheniformis ATCC 14580), was characterized enzymatically. Using human parathyroid hormone (13-34) and p-nitroanilides of peptidyl glutamic acid and aspartic acid, we found a marked difference between BLase and V8 protease, EC 3.4.21.9, although both proteases showed higher reactivity for glutamyl bonds than for aspartyl bonds. Diisopropyl fluorophosphate and benzyloxycarbonyl Leu-Glu chloromethyl ketone completely inhibited BLase, whereas EDTA reversibly inactivated the enzyme. The findings clearly indicate that BLase can be classified as a serine protease. To elucidate the complete primary structure and precursor of BLase, its gene was cloned from the genomic DNA of B. licheniformis ATCC 14580, and the nucleotide sequence was determined. Taking the amino-terminal amino acid sequence of the purified BLase into consideration, the clones encode a mature peptide of 222 amino acids, which follows a prepropeptide of 94 residues. The recombinant BLase was expressed in Bacillus subtilis and purified to homogeneity. Its key physical and chemical characteristics were the same as those of the wild-type enzyme. BLase was confirmed to be a protease specific for glutamic acid, and the primary structure deduced from the cDNA sequence was found to be identical with that of a glutamic acid-specific endopeptidase isolated from Alcalase (Svendsen, I., and Breddam, K. (1992) Eur. J. Biochem. 204, 165-171), being different from V8 protease and the Glu-specific protease of Streptomyces griseus which consist of 268 and 188 amino acids, respectively.

Amino Acid Sequence↗
PubMed1992

A rat brain-derived neurotrophic factor-encoding gene generates multiple transcripts through alternative use of 5' exons and polyadenylation sites.

As a first step toward clarification of the transcriptional controls of the gene encoding brain-derived neurotrophic factor (BDNF), we cloned and sequenced a rat genomic DNA fragment carrying this gene. RNA blotting analysis using a probe derived from the 3'-flanking region of BDNF revealed that alternative use of 3'-polyadenylation sites generates at least two BDNF transcripts that differ in the size of the 3'-noncoding region. Furthermore, sequence analysis of the 5'-end of the BDNF cDNA revealed the presence of at least six different types of transcripts which were probably derived through alternative use of the multiple 5'-exons. Therefore, a single BDNF gene could produce multiple types of transcripts with different noncoding sequences through alternative use of both 5'-exons and 3'-transcription termination sites.

Alternative Splicing↗