巻号一覧
111 巻, 2 号
選択された号の論文の23件中1～23を表示しています
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Hideaki Tsuge, Hideo Ago, Masana Noma, Katsutoshi Nitta, Shintaro Suga ...1992 年 111 巻 2 号 p. 141-143
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーThe crystal structure of a calcium binding equine lysozyme has been determined at 2.5 Å resolution by means of molecular replacement. The energy minimized equine lysozyme as the starting model, was refined with the molecular dynamics program, X-PLOR, and the R factor of the current model was found to be 24% without any water molecules. The conformation of the calcium binding loop is similar to that of α-lactalbumin. The profiles of backbone atomic displacements throughout the lysozyme and α-lactalbumin super-families are comparable as well as their homologous tertiary structures.抄録全体を表示PDF形式でダウンロード (522K) -
Koichi Nishigaki, Misa Tsubota, Toshihisa Miura, Yasuhiro Chonan, Yuzu ...1992 年 111 巻 2 号 p. 144-150
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーA method to convert the conventional denaturing gradient gel electrophoresis into a highly reproducible experimental system was developed. It was based on the following experimental findings; (i) dyes, which are small molecules, do not exhibit mobility changes attributed to their conformational change while nucleic acids do; and (ii) most of the mobility shifts caused by experimental fluctuations could be cancelled by normalizing the mobility of a sample with respect to the corresponding one of a dye. The method involves co-migration of internal reference dyes with samples(nucleic acids), and computer-aided data processing, allowing us to obtain the relative mobility of nucleic acids with respect to a dye throughout the denaturing gradient. The overall pattern of the relative mobilities thus obtained, named the normalized mobility profile (NMP), corresponded well to conformational changes of a macromolecule induced by denaturing effects. This method provides us with objective data without using internal macromolecular references, which not only guarantees the precision but also extends the range of application of the denaturing gradient method.抄録全体を表示PDF形式でダウンロード (1288K) -
Koichi Nishigaki, Toshihisa Miura, Misa Tsubota, Akihiko Sutoh, Norihi ...1992 年 111 巻 2 号 p. 151-156
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーPrecise denaturing gradient gel electrophoresis was effectively applied to various kinds of oligo- and polynucleotides. The analyses on oligonucleotides revealed that every oligonucleotide has its own characteristic normalized mobility profile (NMP), which can be used to identify, characterize and classify the molecules. The precise system also enabled us to obtain unequivocally the mobility transitions corresponding to the melting of hairpin structures of oligonucleotides, single-stranded (ss) DNAs, and RNAs. Another application to co-migration and separate migration experiments demonstrated that there were significant binding interactions between two species of ss molecules of similar mobility, even when they have little complementarity with each other. When the precise temperature gradient gel electrophoresis was applied to double-stranded DNAs, it could be confirmed with high reliability that the mobility transitions observed correspond to cooperative meltings and strand dissociations. Through these experiments, μm, a parameter defined as a mobility transition point, was shown to be effective to deal with those phenomena quantitatively.抄録全体を表示PDF形式でダウンロード (961K) -
Yoshiko Okamoto, Katsutoshi Kuno, Terushige Motohiro, Norio Nishi, Eik ...1992 年 111 巻 2 号 p. 157-161
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーStriped bonito protamine, sardaine, was isolated from the sperm of striped bonito (Sarda orientalis) by extraction with sulfuric acid followed by ion-exchange chromatography. The preparation gave a single band upon polyacrylamide gel electrophoresis. Sardaine consists of 34 amino acid residues, and its sequence is: Pro-Arg-Arg-Arg-Arg-Arg-Ser (Ala)-Ser-Arg-Pro-Val-Arg-Arg-Arg-Arg-Arg-Tyr-Arg-Arg-Ser-Thr-Ala-Ala-Arg-Arg-Arg-Arg-Arg-Val-Val-Arg-Arg-Arg-Arg. At position 7, serine (sardaine Z1) is partially replaced by alanine (sardaine Z2). The ion spray mass spectrum shows that sardaines Z1 and Z2 have molecular masses of 4, 612.49 and 4, 596.09 Da, respectively. The sequence of sardaine Z1 is 100% identical with that of thynnine Z2 from tuna fish (both fish belong to Scombridae, Perciformes).抄録全体を表示PDF形式でダウンロード (1043K) -
Tetsuro Yamashita, Masao Kawakita1992 年 111 巻 2 号 p. 162-167
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーBovine renal brush-border membranes were solubilized by 1.6% sodium cholate. Na+/H+-antiporter was recovered in the supernatant after centrifugation at 160, 000×g for 1h and was successfully reconstituted into proteoliposomes by a cholate-dialysis procedure. The reconstituted Na+/H+-antiporter showed a pH-gradient dependent and amiloridesensitive 22Na+ uptake very similar to that of brush-border membrane vesicles. Factors affecting the efficiency of reconstitution as well as the stability of the solubilized antiporter at various temperatures were studied. Sodium cholate-solubilized brush-border membrane proteins were fractionated by Sephacryl S-400 and DEAE-Toyopearl chromatography, and fractions containing reconstitutively active Na+/H+-antiporter were identified. A 110 kDa peptide cross-reactive with a polyclonal antibody against a C-terminal peptide (22-amino acid residues) of human Na+/H+-antiporter was consistently found on the immunoblot of the active fractions. A closely similar peptide was also detected in human placental membranes by this antibody. These results strongly suggest that the 110 kDa protein is responsible for Na+/H+-antiporter activity.抄録全体を表示PDF形式でダウンロード (970K) -
Ellis L. Kline, Shu-Jen Chiang, David Lattora, Wenren Chaung1992 年 111 巻 2 号 p. 168-174
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーWe have constructed a soybean genomic DNA library in Escherichia coli K12 strain KC13 using plasmid pPV33, which consists of a promoter-less tetracycline resistance (Tcr) gene. A recombinant clone, KC13 (pAU-SB1)+, was obtained by selecting for resistance to tetracycline in the presence of indole-3-acetic acid (IAA). Restriction enzyme cleavage and Southern hybridization analysis revealed that the pAU-SB1 plasmid has a 250 bp soybean DNA insert fused with the Tcr gene. In the presence of a selected group of auxins, induction of the Tcr phenotype and mRNA synthesis of the Tcr gene are observed only in KC13(pAU-SB1)+ cultures. On the other hand, induction of the Tcr phenotype and mRNA synthesis of the Tcr gene are absent in cells harboring the cloning vector pPV33 or a recombinant plasmid containing the 250 bp insert in the reverse orientation, pAU-SB1ro. This demonstrated a need for the insertion of the 250 bp soybean DNA and the specificity of its orientation in response to IAA induction. The start point of mRNA transcription in response to IAA, IBA, IPA, 2, 4, 5-T, and α-NAP is at base pair -96 or -95 upstream of the translational start site of the Tcr gene and base pair -98 with 2, 4-D.抄録全体を表示PDF形式でダウンロード (1799K) -
Makoto Murakami, Ichiro Kudo, Masato Umeda, Atsushi Matsuzawa, Mayuko ...1992 年 111 巻 2 号 p. 175-181
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーPhospholipase A2 activity in lysates of mast cells such as rat mastocytoma RBL-2H3 cells and mouse bone marrow-derived IL-3-dependent mast cells (BMMC) was measured using phosphatidylcholine (PC), phosphatidylethanolamine (PE), or phosphatidylserine (PS) as a substrate. Both types of cells exhibited phospholipase A2 activity with a similar pH profile; the optimum pH observed with PS as a substrate was 5.5-7.4, whereas that with PE or PC was 8.0-9.0. PE and PC bearing an arachidonate at the sn-2 position were cleaved more efficiently by PE, PC-hydrolyzing phospholipase A2 than phospholipids with a linoleate. A monoclonal antibody raised against rabbit platelet 85-kDa cytosolic phospholipase A2 absorbed the PE, PC-hydrolyzing activity. PS-hydrolyzing activity was purified from RBL-2H3 cells and BMMC by sequential heparin-Sepharose, butyl-Toyopearl, and reverse-phase HPLC. On reverse-phase HPLC, the PS-hydrolyzing activity of RBL cells was separated into two peaks, A and B. The peak B activity was inhibited by the anti-rat 14-kDa group II phospholipase A2 antibody, while the peak A activity was not. The partially purified peak A activity hydrolyzed PS about 10-fold more efficiently than PE at optimum pH of 5.5-7.4. No appreciable hydrolysis was observed with PC or phosphatidylinositol (PI). Thus, mast cells may express at least three distinct phospholipases A2; 14-kDa group II phospholipase A2, 85-kDa cytosolic arachidonate preferential phospholipase A2, and a novel phospholipase A2 that shows high substrate specificity for PS.抄録全体を表示PDF形式でダウンロード (1174K) -
Hiroshi Yamashita, Hiroshi Nakatani, Ben'ichiro Tonomura1992 年 111 巻 2 号 p. 182-185
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーInhibition of porcine pancreatic α-amylase (1, 4-α-D-glucan glucanohydrase) [EC 3. 2. 1. 1] with maltotriitol (G3OH) and 4-phenylimidazole was investigated by using maltohexaitol (G6OH) and p-nitrophenyl-α-D-maltoside (G2PNP) as substrates. When G6OH was the substrate, both G3OH and 4-phenylimidazole behaved as competitive inhibitors. On the other hand, when G2PNP was the substrate, G3OH behaved as a competitive inhibitor, whereas 4-phenylimidazole behaved as a non-competitive inhibitor. Further inhibition study in the presence of both G3OH and 4-phenylimidazole, with G6OH as the substrate, showed that the two inhibitors compete with each other for the active site of the enzyme. Based on a consideration of the productive (reactive) binding modes of G2PNP and G6OH, and a nonproductive (nonreactive) binding mode of G2PNP, it is suggested that the binding sites of the two inhibitors may be partially overlapping around the catalytic site of the enzyme and that the rest of the binding site of each inhibitor lies along the substrate binding cleft of the enzyme.抄録全体を表示PDF形式でダウンロード (408K) -
Akira Yoshida, Masami Takahashi, Toshiaki Imagawa, Munekazu Shigekawa, ...1992 年 111 巻 2 号 p. 186-190
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーWe studied β-adrenergic agonist-stimulated phosphorylation of the ryanodine receptor in rat cardiac myocytes. The ryanodine receptor solubilized from myocytes and immunoprecipitated by a monoclonal antibody against canine cardiac ryanodine receptor was phosphorylated by the catalytic subunit of cAMP-dependent protein kinase (PKA). Incubation of saponin-permeabilized myocytes with [ γ-32P]ATP also induced ryanodine receptor phosphorylation, which was enhanced significantly in the presence of isoproterenol. This stimulating action of isoproterenol was suppressed by the β-adrenergic antagonist, propranolol. On the other hand, exogenously added cAMP caused a much larger stimulation of phosphorylation of the ryanodine receptor in permeabilized myocytes. The β-agonistinduced phosphorylation of the ryanodine receptor was also observed in intact myocytes from the newborn rat heart. These results suggest that the ryanodine receptor is phosphorylated by PKA during β-adrenergic stimulation of cardiac myocytes.抄録全体を表示PDF形式でダウンロード (1224K) -
Akira Abe, Jin-ichi Inokuchi, Masayuki Jimbo, Hiroshi Shimeno, Atsuo N ...1992 年 111 巻 2 号 p. 191-196
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーAn inhibitor of glucosylceramide (G1cCer) synthase, 1-phenyl-2-decanoylamino-3-morpholino-1-propanol (PDMP), has been reported to deplete cells and mice of their glucosphingolipids. This inhibitor has proved useful for the elucidation of the many functions of this lipid family [reviewed by Radin, N. S. & Inokuchi, J. (1991) Trends Glycosci. Glycotechnol. 3, 200-213]. In the present study, we have synthesized homologs of PDMP having different acyl chains (C6-C18) and compared their effectiveness for the inhibition of GlcCer synthase in vitro and their inhibition of G1cCer, protein, and DNA synthesis in cultured MDCK (Madin-Darby canine kidney) cells. Using MDCK homogenates and mouse brain and liver microsomes, we found that the C6 compound was relatively inactive and that the longer chain compounds did not differ much in inhibitory power. However, the use of intact MDCK cells showed that the longer chain homologs were much more effective in inhibiting GlcCer synthesis, cell growth, and incorporation of [3H]thymidine. Tests with two radioactive homologs showed that the inhibitor with a longer acyl chain was taken up much more effectively by MDCK cells and that this difference explains the much greater effectiveness of this homolog in intact cells. The inhibitors were effective when solubilized either with a nonionic detergent or with bovine serum albumin. The extent of decrease in DNA synthesis was not directly proportional to the decrease in cellular glucosylceramide, possibly because only a low level of the glycolipid is needed for DNA synthesis.抄録全体を表示PDF形式でダウンロード (808K) -
Takahiro Fujino, Tokuo Yamamoto1992 年 111 巻 2 号 p. 197-203
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーComplementary DNA clones encoding a protein highly homologous to the previously characterized long-chain acyl-CoA synthetase (LACS) in liver were isolated from rat brain cDNA libraries. This protein consists of 697 amino acids and has 64.7% identity with the rat liver LACS sequence. The brain protein and the liver LACS share essentially the same domain structure, having two regions similar to those of click beetle luciferase and a long discrete gap flanking the similar domains. A significant sequence similarity was found between the brain protein and malaria octapeptide-repeat antigen, suggesting a functional similarity. COS cells transfected with the cDNA for the brain protein expressed LACS activity with slightly different fatty acid specificity from that of the liver LACS. This new LACS is expressed predominantly in brain and, to a much lesser extent, in heart and adrenal. The 2.9- and 6.3-kb mRNAs coding for the brain enzyme are coregulated with the development of brain, suggesting the physiological importance of the enzyme in fatty acid metabolism in brain.抄録全体を表示PDF形式でダウンロード (3174K) -
Yukihiro Isoda, Yasuomi Shimizu, Akimitsu Hashimoto, Hiroshi Fujiwara, ...1992 年 111 巻 2 号 p. 204-209
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーMichaelis constants (Kms) and molecular activities (kos) of phenyl, p-nitrophenyl and p-methylphenyl α-maltoside for taka-amylase A catalyzed hydrolyses were determined in H2O and in D2O at pH or pD 5.3 and at 25°C. Production of α-maltose in the hydrolysis was confirmed by 1H NMR. Neither substituent nor solvent deuterium isotope effects on Kms for phenyl, p-nitrophenyl and p-methylphenyl α-maltosides were detected. On the other hand, substituent effects on kos of these compounds were evident, but the isotope effects on kos were not marked, so that protonation of the substrate in the catalytic reaction might not be rate-limiting. The result indicates that nucleophilic attack of a carboxylate anion of the enzyme upon the protonated substrate is the rate-limiting step in the hydrolysis proceeding through the nucleophilic double displacement mechanism, which involves a covalently bonded glycosyl intermediate. The molecular orbitals of phenyl α-D-glucosides as model compounds of phenyl α-maltosides were calculated by the AM1 method. From the results, it was concluded that the lowering of the lowest unoccupied molecular orbital (LUMO) energy levels and the increase of distribution of LUMO on the anomeric carbon, C-1, of the compounds are caused by protonation at the glycosidic oxygen from the protonated carboxyl group of the enzyme. This causes acceleration of the hydrolysis of a substrate by the enzyme.抄録全体を表示PDF形式でダウンロード (643K) -
Hiroko Nishimura, Seiji Inoue, Kiyoshi Ikeda, Keizo Teshima, Yuji Same ...1992 年 111 巻 2 号 p. 210-218
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーEffects of Ca2+ on the kinetic parameters for the hydrolysis of mixed micelles of 1, 2-dipalmitoyl-sn-glycero-3-phosphorylcholine (diC16PC) with Triton X-100, catalyzed by a cobra (Naja ndja atra) (Group I) and a Habu (Trimeresurus flavoviridis) (Group II) PLA2s, were studied and compared with the results reported for other Group I and II enzymes. The substrate bindings to Group I enzymes were independent of the Ca2+ binding, whereas the substrate bindings to Group II enzymes were facilitated more than 10 times by the Cal2+ binding to the enzymes. The result for Group II enzymes, but not Group I enzymes, seemed compatible with the hypothesis for interpreting the catalytic mechanism that an intermediate complex should be stabilized by the coordination of the bound Ca2+ with the phosphoryl group and the carbonyl oxygen atom of the ester bond at the sn-2 position of the bound substrate molecule [ Verheij et al. (1980) Biochemistry 19, 743-750 and (1981) Rev. Physiol. Biochem. Pharmacol. 91, 91-203]. The pH dependence of the kinetic parameters for the hydrolysis of the mixed micellar diC16PC, catalyzed by the cobra (N. naja atra) (Group I) and Habu (T. flavoviridis) (Group II) PLA2s, was also studied. The pK values of the catalytic group, His 48, and Tyr 52 for N. naja atra PLA2, shifted from 7.25 to 7.70 and from 10.30 to 10.85, respectively, and the corresponding values for T. flavoviridis PLA2 shifted from 5.80 to 6.95 and from 10.10 to 10.76, respectively, on binding of the micellar substrates to the enzymes. On the other hand, no participation of these ionizable groups was observed for the bindings of monodispersed substrates [Teshima et al. (1985) J. Biochem. 98, 1509-1517 and Teshima et al. (1989) J. Biochem. 105, 1044-1051 ]. Consequently, it was concluded that the increases in the pK values of His 48 and Tyr 52 on binding of micellar substrates to PLA2s were a property common to both types of enzymes (Groups I and II).抄録全体を表示PDF形式でダウンロード (909K) -
Masaki Nakamura, Masayuki Yamagishi, Fuminori Yoshizaki, Yasutomo Sugi ...1992 年 111 巻 2 号 p. 219-224
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーThe green alga Pediastrum boryanum synthesizes alternatively two photosynthetic electron carrier proteins, plastocyanin and cytochrome c-553, depending on the copper concentration of the medium. We studied the levels at which the syntheses of the two proteins are regulated. Plastocyanin and cytochrome c-553 were purified from P. boryanum NIES-301 cells, having apparent molecular weights of 14, 600 and about 12, 000, respectively. Western blotting with antisera raised against these proteins showed accumulation of (apo) plastocyanin and (apo) cytochrome c-553 in the cells grown with (2μM) and without added CuSO4, respectively, but no accumulation of the precursor proteins in both cultures. The translatable mRNAs for the two proteins were examined by in vitro translation with total RNA and wheat germ extract followed by immunoprecipitation and SDS-PAGE. The 21-kDa polypeptide (preapoplastocyanin) was detected with anti-plastocyanin serum in copper-sufficient cells; the 23-kDa polypeptide (preapocytochrome c-553) with anti-cytochrome c-553 serum in copper-deficient cells. The translatable mRNA for preapoplastocyanin appeared in 1h and (apo) plastocyanin in 2-3h after the addition of 2μM CuSO4 to the copper-deficient culture. The translatable mRNA for preapocytochrome c-553 disappeared within 4-5h, while (apo) cytochrome c-553 disappeared more slowly. It is concluded that the syntheses of plastocyanin and cytochrome c-553 are regulated by copper at the pre-translational (i.e., transcriptional or post-transcriptional) level in P. boryanum NIES-301.抄録全体を表示PDF形式でダウンロード (4610K) -
Takayuki Jikibara, Kaoru Takegawa, Shojiro Iwahara1992 年 111 巻 2 号 p. 225-229
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーAn acidic heteropolysaccharide preparation derived from the mycelium of Fusarium sp. M7-1 was fractionated into two fractions, precipitable and nonprecipitable, by treatment with cetyltrimethylammonium bromide (Cetavlon). These two fractions were further purified to apparent homogeneity on ultracentrifugation by treatment with charcoal and gel filtration chromatographies. Two glycoproteins, precipitable GP I and nonprecipitable GP II, were obtained. The molecular weighs of GP I and GP II were estimated to be about 8.8×104 and 3.7×104, respectively, on gel filtration chromatography. Both GP I and GP II contained a high proportion of serine and threonine. Treatment of GP I and GP II with alkaline solution resulted in an increase in absorbance at 240nm. Alkaline borohydride treatment markedly decreased the number of seryl and threonyl residues and resulted in an increase in alanine and the formation of 2-aminobutyric acid. It also resulted in release of low and high molecular weight carbohydrate chains. From these results, we conclude that both GP I and GP II are glycoproteins with carbohydrate chains attached to the protein moiety through O-glycosidic linkages to the hydroxyl group of serine and/or threonine.抄録全体を表示PDF形式でダウンロード (1403K) -
Takayuki Jikibara, Keiko Tada, Kaoru Takegawa, Shojiro Iwahara1992 年 111 巻 2 号 p. 230-235
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーThe primary structures of the O-glycosidically linked oligosaccharides isolated from glycoproteins GP I and GP II of Fusarium sp. M7-1 were established. The oligosaccharides released by alkaline borohydride treatment from the glycoproteins were purified by Bio-Gel P-4 and HPLC. This approach resulted in one monosaccharide and seven oligosaccharides. Their primary structures were resolved mainly by NMR spectrometry in combination with methylation mass spectrometry and fast atom bombardment mass spectrometry. The following structures have been determined.抄録全体を表示PDF形式でダウンロード (566K) -
Takayuki Jikibara, Kaoru Takegawa, Shojiro Iwahara1992 年 111 巻 2 号 p. 236-243
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーTwo O-glycosidically linked acidic polysaccharides, AP I and AP II, were released, respectively, from glycoproteins GP I and GP II of Fusarium sp. M7-1 by alkaline borohydride treatment and purified by gel filtration chromatography. They were found to be apparently homogeneous on gel filtration chromatography and analytical ultracentrifugation. Their molecular weights were estimated to be 8.2×104 and 3.1×104, respectively. The various oligosaccharide fragments obtained from AP I and AP II by acetolysis and partial acid hydrolysis were purified by gel filtration chromatography and HPLC. Their primary structures were resolved mainly by NMR spectrometry in combination with methylation mass spectrometry. Analyses of the acetolysis and partial acid hydrolysis products and the 1H-NMR spectrum of AP I and AP II showed that they are analogues. Thus, we propose that the main parts of the acidic polysaccharides have the following structures.
*X, unidentified oligosaccharide chains. The numbers on the left and the numbers in parentheses outside the brackets indicate the approximate number of side chains of AP I and AP II, respectively, the saccharide sequences of which are not specified.抄録全体を表示PDF形式でダウンロード (1879K) -
Munekiyo Kaneko, Yoichi Sakata, Michio Matsuda, Jun Mimuro1992 年 111 巻 2 号 p. 244-248
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーWe have shown that plasminogen activator inhibitor-1 (PAI-1) inhibits the fibrin binding of both the single chain and two chain forms of tissue-type plasminogen activator (tPA) through two different mechanisms. PAI-1 inhibits the finger domain-dependent fibrin binding of diisopropylfluorophosphate- inactivated single chain tPA and the kringle-2 domain-dependent fibrin binding of diisopropylfluorophosphate-inactivated two chain tPA. In accordance with the data, preformed complexes of single chain tPA/PAI-1 and of two chain tPA/PAI-1 lost the fibrin binding abilities mediated by the finger and kringle-2 domains, respectively. These effects of PAI-1 appear to be mediated by steric hindrance of the fibrin binding sites after PAI-1 binding to adjacent regions in the functional domains of tPA. We thus propose a model in which a PAI-1 binding site resides in the finger domain of a single chain, and plays a role in the reversible association of single chain tPA and PAI-1. Conformational changes may take place during the conversion of single chain tPA to two chain tPA, resulting in burying of the original PAI-1 binding site and exposure of an alternate PAI-1 binding site on the surface of the kringle-2 domain.抄録全体を表示PDF形式でダウンロード (599K) -
Yoshiki Habu, Surin Peyachoknagul, Katsuhiro Umemoto, Yoichi Sakata, T ...1992 年 111 巻 2 号 p. 249-258
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーWe analyzed the structure and the expression of Kunitz chymotrypsin inhibitor (WCI) genes in winged bean. WCI was encoded by a multigene family which comprised at least seven members. From their primary structures, four genes (WCI-2, WCI-3a, WCI-3b, and WCI-x) were expected to be functional ones and the other three (WCI-P1, WCI-P2, and WCI-P3) to be pseudogenes. The nucleotide sequences of the WCI-3a and WCI-3b genes were nearly identical, and they encoded the WCI-3 protein, the major chymotrypsin inhibitor in seeds. The WCI-2 gene also encoded the chymotrypsin inhibitor found in seeds and the WCI-x gene was expected to encode an unidentified chymotrypsin inhibitor. WCI messenger RNA and protein accumulated mainly in developing seeds and tuberous roots, small amounts of WCI mRNA being present in stems and pericarps. In seeds, transient accumulation of WCI mRNA was observed during the seed maturation period. These results suggest that the expression of WCI genes is regulated organ-specifically and developmentally in winged bean.抄録全体を表示PDF形式でダウンロード (5751K) -
Jiro Seki, Xiaohui Wang, Akemi Ota, Yasuhiko Suzuki, Nobuo Sakato, Haj ...1992 年 111 巻 2 号 p. 259-264
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーThree epitope peptides of hen egg-white lysozyme (HEL) were tested for ability to induce antibodies reactive with native HEL. Each peptide was coupled to bovine γ-globulin (BγG) and 4 rabbits were immunized with each peptide-BγG conjugate in complete Freund's adjuvant. The mean association constants (Kos) of HEL-reactive antibodies (HEL-R-Abs) from each immunizing group to [3H]acetyl HEL or to [3H]acetyl-peptide were measured in solution by a double antibody method. Only peptide loop I•II (sequences 57-107 containing Cys64-Cys80 and Cys76-Cys94) induced high-affinity antibodies to HEL (Ko=2.5×106-2.3×107M-1) among the three epitope peptides tested. The association constants of antipeptide loop I•II to [3H] acetyl peptide loop I•II were always one to two orders of magnitude higher than those to HEL. In addition, 50 to 80% of the anti-peptide loop I•II antibodies were reactive with native HEL. The specificity of anti-peptide loop I•II was directed to a conformational feature of the peptide rather than to native HEL and reactivity of the antibody to HEL was interpreted as a kind of cross-reaction. The HEL-R-Abs from anti-Ploop I•II antisera also manifested neutralizing activities against the enzymic activity of HEL when Micrococcus luteus was used as the substrate.抄録全体を表示PDF形式でダウンロード (811K) -
Retinoic Acid-Specific Induction of a Protein Kinase C Isoform during Differentiation of HL-60 CellsYasuharu Tanaka, Koichiro Yoshihara, Motokatsu Tsuyuki, Asako Itaya-Hi ...1992 年 111 巻 2 号 p. 265-271
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーHuman promyelocytic leukemia cells (HL-60) were treated with several differentiation inducers, then the changes in the activity of cytosolic protein kinase C (PKC) isoforms were examined by hydroxylapatite chromatography and the species of the isoforms were determined immunologically. In three undifferentiated HL-60 cell lines examined, PKC α and β isoforms were present, but PKC γ isoform was not detected. When the cells were induced by dimethylsulfoxide, dibutyryl cAMP, or nicotinamide to differentiate into granulocytes, these two PKC isoforms each increased to about 2- to 3-fold. When retinoic acid was used as the inducer, in addition to PKC α and β, a third PKC isoform appeared. This isoform was clearly distinct from rat PKC α, β, andγ, immunologically. This isoform showed a distinctly lower Ca2+-requirement (3μM) than that of PKC α or β (100μM) and was more dependent on cardiolipin and phosphatidylethanolamine, compared with PKC α, β, and γ. These results suggest that while the increases in the activities of PKC α and β isoforms are common in the differentiation program initiated by several inducers, including retinoic acid, the emergence of an unclassified PKC isoform is a retinoic acid-specific process.抄録全体を表示PDF形式でダウンロード (896K) -
Noriaki Shimizu, Mitsue Ohta, Chie Fujiwara, Junji Sagara, Naoko Mochi ...1992 年 111 巻 2 号 p. 272-277
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーETR103 cDNA was cloned as an immediate early gene in the course of macrophagic differentiation of HL-60 cells stimulated by TPA (12-O-tetradecanoylphorbol-13-acetate). The induction by TPA was immediate-early (within 30min) and transient. This gene was not induced by vitamin D3 or by retinoic acid, which stimulates differentiation of HL-60 cells to the monocytic or granulocytic lineage, respectively. The ETR103 mRNA was induced by TPA in lymphoid or myeloid leukemia cell lines of several maturation stages. The induction by TPA seems to proceed by a protein kinase C-mediated mechanism, on the basis of the results obtained by using protein kinase C inhibitor (H-7), protein kinase C activator (diC8), and an activator of protein kinase A (dibutyryl cAMP). Okadaic acid, an inhibitor of protein phosphatases, also induced the ETR103 mRNA expression. The nucleotide sequence of the ETR103 cDNA reveals that ETR103 encodes a human zinc fingercontaining transcription factor identical to Egr-1 and 225, which is homologous to mouse Egr-1, Zif/268, Krox-24, and TIS8, or to rat NGFI-A.抄録全体を表示PDF形式でダウンロード (3071K) -
Eiki Kominami, Junji Ezaki, Daisaku Muno, Kazumi Ishido, Takashi Ueno, ...1992 年 111 巻 2 号 p. 278-282
発行日: 1992年
公開日: 2008/11/18
ジャーナル フリーImmunochemical studies demonstrated the specific accumulation of subunit c of mitochondrial ATP synthase in the brain homogenates of late infantile and juvenile forms of Batten's disease. It is not stored in the infantile form. Storage of subunit α of mitochondrial ATP synthase and cytochrome c oxidase subunit IV, an inner membrane protein of mitochondria was not detected in the brains. There was also no difference in the levels of cathepsin B between the two forms of Batten's disease and controls. In cultured skin fibroblasts subunit c accumulates in the late infantile form, whereas it does not in other lysosomal storage diseases. Crude mitochondrial lysosomal preparations of control fibroblasts were separated into high-density fractions rich in a lysosomal marker and low-density fractions rich in a mitochondrial marker on Percoll density gradients. Subunit c was mostly recovered in low-density mitochondrial fractions, but in cells from the late infantile disease a part of subunit c was recovered in the high-density lysosomal fractions. Immunolocalization studies demonstrated a dot-like staining of storage materials for subunit c in the cells from late infantile patients and the staining pattern of subunit c is similar to that of a lysosomal membrane marker, lgp120. Immunostaining failed to detect subunit c in control cells. These results indicate a specific accumulation of subunit c in lysosomes, and suggest that the two forms of Batten's disease are caused by a specific failure in the degradation of subunit c.抄録全体を表示PDF形式でダウンロード (4401K)
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