All issues
Volume 121 (1997)
- Issue 6 Pages 997-
- Issue 5 Pages 811-
- Issue 4 Pages 633-
- Issue 3 Pages 399-
- Issue 2 Pages 179-
- Issue 1 Pages 1-
Volume 121, Issue 5
Displaying 1-29 of 29 articles from this issue
- |<
- <
- 1
- >
- >|
-
Yoshihiro Yoneda1997 Volume 121 Issue 5 Pages 811-817
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSNuclear proteins are transported actively through nuclear pores by a selective, mediated process. The process is mediated by a nuclear localization signal (NLS), and can be divided into at least two steps, (a) targeting to the pores and (b) translocation through the pores. The first step involves the formation of a stable complex containing a nuclear protein, termed nuclear pore-targeting complex (PTAC), in the cytoplasm. The second step, translocation, requires at least two soluble factors, a small GTPase Ran and its interacting protein p10/ nuclear transport factor 2 (NTF2), along with nuclear pore complex components. These findings have been generally obtained by using the NLS of SV40 large T-antigen, and data concerning the detailed mechanism are now accumulating. Transport pathways other than for the SV40 T-antigen, for example, extracellular signal-dependent nuclear protein import pathway, have also recently been studied. Considering allthese observations, one should be able to attain an understanding of the mechanism of intracellular information transduction between cytoplasm and the nucleus.View full abstractDownload PDF (977K) -
Yuan C. Lee1997 Volume 121 Issue 5 Pages 818-825
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSFluorometric spectroscopy is a powerful tool for investigating the interaction between a carbohydrate ligand and binding proteins. The measurement is done in situ and thus circumventing the need for separation of bound ligand from the free ligand. The source of the fluorophore can be intrinsic, i. e., the tryptophan in the protein, or extrinsic (contained in the ligand). Techniques for assessing the affinity used are measurement on fluorescence intensity change, lifetime, polarization anisotropy, and energy transfer. The last technique can also be used to study conformational structures of glycopeptides. It is also useful in designing substrates for endo-type enzymes which allow continuous monitoring of the reaction.View full abstractDownload PDF (956K) -
Zui Fujimoto, Hiroshi Mizuno, Atsushi Kuno, Shigeki Yoshida, Hideyuki ...1997 Volume 121 Issue 5 Pages 826-828
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSβ-Xylanase from Streptomyces olivaceoviridis E-86 has been crystallized by the hangingdrop vapor diffusion method from 25% saturated. ammonium sulfate and 2% McIlvainebuffer, pH 5.7. The crystals diffract to at least 1.9Å resolution, and belong to space group P212121, with unit-cell dimensions of a=79.6Å, b=95.2Å, and c=140.3Å. There areprobably two xylanase molecules (MW=45K) per asymmetric unit.View full abstractDownload PDF (1693K) -
Seigo Shima, Marcel Goubeaud, Daniela Vinzenz, Rudolf K. Thauer, Ulric ...1997 Volume 121 Issue 5 Pages 829-830
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSMethyl-coenzyme M reductase isoenzyme I from the methanogenic Archaeon, Methanobac-terium thermoautotrophicum (strain Marburg), was crystallized by vapor diffusion meth-ods. Crystal form M obtained with 2-methyl-2, 4-pentanediol as the precipitantdisplayed space group P21, with unit cell parameters of a=83.2Å, b=117.4Å, c=125.1Å, and β=92.6Å, and diffracted at better than 2.8Å resolution. Crystal form P grown from polyethylene glycol 400 belonged to space group P21, and had unit cell parameters of a=83.1Å, b=120.2Å, c=123.1Å, and β=91.7Å, diffracting at least to 1.7Å resolution. Both crystal forms have one molecule per asymmetric unit and are suitable for X-ray structure analysis.View full abstractDownload PDF (1427K) -
D. Luo, M. Geng, A. A. Noujaim, R. Madiyalakan1997 Volume 121 Issue 5 Pages 831-834
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSBivalent single chain Fv (scFv) was constructed by fusing a polypeptide extension containing one or two cysteines to the COOH-terminus of an scFv antibody fragment. ThescFv protein was expressed and secreted in a recombinant Pichia pastoris system as adieter with a C-terminal disulfide bridge, as determined by Western blot analysis undernon-reducing conditions. We found that the scFv construct with one cysteine in the C-extension (scFv-1Cys) exhibited a much higher dimer/monomer ratio than the two cysteinecounterpart (scFv-2Cys). Binding activity measurements performed by means of a competitive radioimmunoassay showed that scFv-ICys exhibited specific antigen binding activity, which was almost the same as that of the parental MAb, and approximately four- andfortyfold higher than those of the control scFv monomer and scFv-2Cys.View full abstractDownload PDF (1483K) -
Hiroyuki Hanzawa, Hideyuki Haruyama, Kiyoshi Konishi, Kazuyoshi Watana ...1997 Volume 121 Issue 5 Pages 835-841
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSRat CINC/Gro is a 72 residue chemotactic factor of neutrophils, and a member of the CXC chemokine family, that includes IL-8 and MGSA/GRO. Although the three-dimensional structure of CINC/Gro had previously been determined to be that of a dimer with 200 mM NaCl, it was shown on both ultracentrifugation analysis and 1H-NMR spectral analysis that CINC/Gro exists mainly as a monomer at a physiological concentration, similar to other proteins belonging to this family. By reducing the NaCl concentration, the equilibrium could be shifted to the monomer, making it possible to observe the monomer and dimer resonances in 1H-NMR spectra. There were no significant chemical shift changes of α protons in the β sheet between the monomer and dimer, suggesting that the β sheet structure was retained in the monomer. Instead, the chemical shift changes of α protons were significant at 118 and K21, which are located in the long loop region interacting with the α helix, and V59 at the beginning of the α helix, indicating structural changes in the relative positions of the α helix and β sheet.View full abstractDownload PDF (4012K) -
Shiken Sha, Kazunobu Minakuchi, Noriko Higaki, Kenji Sato, Kozo Ohtsuk ...1997 Volume 121 Issue 5 Pages 842-848
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSWe purified and characterized glutaredoxin (thioltransferase), which catalyzes thiol/ disulfide exchange reaction, for the first time in plants. The purification procedure em-ployed an immunoabsorbent, antiglutaredoxin-Sepharose. Glutaredoxin was purified about 2, 200-fold from rice bran and it appeared to be homogeneous on SDS-PAGE. MALDI-TOF mass spectrometry revealed that the protein has a molecular mass of 11, 097. 9 Da. Rice glutaredoxin consists of 105 amino acid residues, containing the tetrapeptide-Cys-Phe-Pro (Tyr)-Cys-, which constitutes the active site of Escherichia coli and mammalian glutaredoxins. Inactivation assay also indicated that cysteine residues are responsible for enzyme activity. Kinetic analyses revealed that the enzyme did not exhibit normal Michaelis-Menten kinetics. The enzyme has an optimum pH of about 8.7 with 2-hydroxyethyl disulfide as a substrate. In addition, rice glutaredoxin has dehydroascor-bate reductase activity, like mammalian glutaredoxin.View full abstractDownload PDF (1797K) -
Masachika Irie, Kazuko Ohgi, Masanori Iwama, Machiko Koizumi, Etsuko S ...1997 Volume 121 Issue 5 Pages 849-853
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSIn order to study the reaction mechanism of RNase Rh from Rhizopus niveus, the rates of cleavage of four 2', 3'-cyclic nucleotides by mutant enzymes of RNase Rh, H46F, H109F, E105Q, and K108L were measured. H46F is virtually inactive towards cyclic nucleotides, but H109F hydrolyzed these substrates at 0.7-4.5% of the rates of the native RNase Rh. The other mutants hydrolyzed 2', 3'-cyclic nucleotides at 15-20% of the rates of the native enzyme. Relative enzymatic activities towards four cyclic nucleotides of H109F in the hydrolysis reaction (2nd step) were much higher than in the transphosphorylation reaction (the 1st step). In the presence of a 13-fold excess of uridine, H109F catalyzed the transphos-phorylation reaction of 2', 3'-cyclic AMP (A>p) to ApU. However, this reaction was not catalyzed by H46F mutant or native RNase Rh. These results showed that His46 is crucial to the hydrolysis reaction, and to the reversed reaction of the transphosphorylation reaction. We suggest that His46 in RNase Rh plays a major role in these reactions by acting as a base catalyst to activate water and the 5'-hydroxyl group of nucleosides, respectively.View full abstractDownload PDF (630K) -
Tomoaki Niimi, Kiyoshi Miki, Yasuo Kitagawa1997 Volume 121 Issue 5 Pages 854-861
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSMouse laminin αl, β1, or γ1 sequence covering truncated regions of the long arm wastransiently expressed in monkey COS1 cells. Unlike natural laminins, in which only αβγ trimers are selectively assembled and disulfide-bonded at the long arm, a large fraction of mouse chains formed disulfide-bonded homopolymers. However, a small fraction of mouse β1 (or γ1) formed hybrid β1γ1 dimers with endogenous monkey γ1 (or β1). These hybrid β1γ1 dimers formed α1β1γ1 trimer with monkey αl. Mouse αl also formed disulfide bonds with monkey 3171 dimer. Thus, a common mechanism is shared by laminin chains of different animal origins. Sequences in the E8 region at the C-terminal end of the long arm were crucial for this chain-selective assembly. When the C-terminal sequence of mouse βl long arm was extended beyond the α-loop, the hybrid trimer formation was diminished. This supported the model of altered chain arrangement around the α-loopView full abstractDownload PDF (3406K) -
Satsuki Kamisato, Yuko Uemura, Noboru Takami, Kouji Okamoto1997 Volume 121 Issue 5 Pages 862-867
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSα-Elastin with an average molecular mass of 70 kDa, an oxalic acid fragmentation product of highly purified insoluble elastin, induced the migration of macrophages, with maximum activity at 10-1 μg/ml. Relative to the positive control of 10-8 M N-formylmethionyl-leucyl-phenylalanine (fMLP), the responsiveness of macrophages to α-elastin was nearly the same. Checkerboard analysis demonstrated that the cell movement is chemotaxis and not chemokinesis. A homologous deactivation test showed the possibility of the existence of α-elastin-recognizing sites on macrophages. In connection with macrophage chemotaxis in response to α-elastin, the intracellular signaling pathway was examined. The guanosine 3', 5'-cyclic monophosphate (cGMP) level was enhanced in macrophages stimulated by α-elastin, whereas the adenosine 3', 5'-cyclic monophosphate (cAMP) level was not. Chemotaxis assaying of macrophages treated with 8-Br cGMP- and dibutyryl cAMP-loaded macrophages indicated that cGMP promotes cell movement and cAMP suppresses cell locomotion. The possible involvement of protein kinases in the α-elastin signaling pathway was explored by use of inhibitors specific for cGMP-dependent protein kinase (PKG), CAMP-dependent protein kinase (PKA), protein kinase C (PKC), and tyrosine kinase. The macrophage chemotactic response to α-elastin was inhibited by the PKG inhibitor, but not by the PKA, PKC, or tyrosine kinase inhibitor. These results suggested that the increase in the cGMP level and the activation of PKG in macrophages are involved in α-elastin- induced macrophage chemotaxis.View full abstractDownload PDF (767K) -
Takayuki Nishijyo, Akira Kawada, Takuya Kanno, Masakazu Shiraiwa, Hide ...1997 Volume 121 Issue 5 Pages 868-875
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSPeptidylarginine deiminase (PAD) is a posttranslational modification enzyme that catalyzes deimination of arginine residues of proteins in the presence of calcium ions. There are three types of PAD in rodent tissues: PAD types I, II, and III [Terakawa et al. (1991) J. Biochem. 110, 661-666] . Type III enzyme was detected only in the epidermis and in hair follicles. In this study, we have purified PAD type III from 2-day-old rat epidermis by a four-step procedure that included soybean trypsin inhibitor-affinity chromatography. The enzyme was purified about 600-fold from the crude extract and the recovery was 23%. The final preparation of the enzyme gave only a single protein band on SDS-PAGE and showed an apparent molecular weight of 76, 000. Subsequently, we cloned and sequenced the full-length cDNA encoding rat PAD type III by reverse transcription-polymerase chain reaction (RT-PCR) using degenerate oligonucleotide primers designed from the internal amino acid sequences and by the rapid amplification of the cDNA ends method. The composite cDNA sequence contained a 5' untranslated region of 42 bp, an open reading frame of 1, 995 bases that encoded 664 amino acids (Mr =75, 036), a 3' untranslated region of 1, 063 bp, and part of a poly(A)+ tail. The entire reading frame sequence of rat PAD type III showed 51% homology with that of rat PAD type II, and the C-terminal region is highly conserved between the two types. The cloned gene was expressed in Escherichia coli cells to produce PAD type III, which had not only enzymatic activity, but also immunoreactivity against specific antibodies toward PAD type II. Furthermore, the specific expression of the enzyme in the epidermis and hair follicles was confirmed by RT-PCR assays of mRNAs from several tissues.View full abstractDownload PDF (3293K) -
Ken'ichi Mihara, Osamu Hisatiomi, Yasushi Imamoto, Mikio Kataoka, Fumi ...1997 Volume 121 Issue 5 Pages 876-880
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe gene encoding photoactive yellow protein (PYP) was isolated from Ectothiorhodospira halophila, and a high-level expression system for PYP was constructed in Escherichia coli. The molecular weight and the absorption spectrum of PYP expressed in E. coli were identical with those of the native PYP isolated from E. halophila. The amino acid residues which might interact with the chromophore (Tyr42, Glu46, Thr50, Arg52, and Cys69) were mutated by site-directed mutagenesis and the absorption spectra of these mutants were exmained to study the chromophore/protein interaction in PYP. The former three substitutions (Y42F, E46Q, and T50V) Brought about no change and that of Cys69 (C69S) led to no formation of pigments. These results suggest that Tyr42, Glu46, and Thr50 strongly interact with the chromophore, while Arg52 does not contribute the color tuning of PYP.View full abstractDownload PDF (601K) -
Shigeru Kawahire, Masaki Takeuchi, Takashi Gohshi, Satoru Sasagawa, Mi ...1997 Volume 121 Issue 5 Pages 881-889
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSWe previously purified and characterized a nuclear localization signal (NLS) binding protein, NBP60, in rat liver nuclear envelopes. In this study, we cloned and sequenced the cDNA of rat NBP60, and predicted an amino acid sequence comprising 620 amino acids. The sequence revealed that NBP60 is a rat homologue of lamin B receptor (LBR), and is 79 and 63% identical in amino acids to human and chicken LBR, respectively. Using three fusion proteins containing different parts of the amino-terminal domain of human LBR, it was shown that the stretch comprising amino acids 1 to 89, which contains a Ser-Arg rich region (RS region), binds to nucleoplasmin and that the binding was inhibited by a common NLS-peptide. These results suggested that the amino-terminal domain of LBR contains an NLS-binding site. Furthermore, it was shown that the stretch comprising amino acids 1 to 53, which does not contain the RS region or the predicted DNA-binding site, binds to Xenopus laevis sperm chromatin.View full abstractDownload PDF (3718K) -
Masaki Kanazawa, Kazutoyo Terada, Seishi Kato, Masataka Mori1997 Volume 121 Issue 5 Pages 890-895
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe role of HSDJ, a human homolog of bacterial DnaJ and yeast YDJ1p/MAS5, in mitochondrial protein import was examined. Recombinant HSDJ was purified and an antibody was prepared. HSDJ mRNA was heat-induced in cultured cells. In pulse-labeling and chase experiments using COS-7 cells, the endogenous HSDJ homolog was prenylated. Transiently expressed HSDJ was also prenylated, whereas its mutant C394S in which cysteine of the “CaaX box” was mutated to serine, was not. HSDJ, but not C394S, synthe-sized in rabbit reticulocyte lysate was farnesylated. The HSDJ antibody inhibited importof ornithine transcarbamylase precursor (pOTC) into isolated mitochondria when addedprior to pOTC synthesis, but not when added prior to import assay. In transient expressionof pOTC in COS-7 cells, pOTC was synthesized and processed to the mature form with anapparent half-life of 2-3 min. Coexpression of HSDJ or C394S resulted in slight retardationof the pOTC processing. These results indicate that HSDJ is involved in an early step(s) ofprotein import into mitochondria.View full abstractDownload PDF (4671K) -
Yoshiro Kobayashi, Hidemasa Nagatake, Osamu Shimozato, Naoko Watanabe1997 Volume 121 Issue 5 Pages 896-901
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe two interleukin 1 precursors (preIL-1αla and β) with a molecular mass of 33 kDa are proteolytically processed to the mature carboxyl-terminal 17-kDa proteins. In this study we newly developed a monoclonal antibody against the precursor domain of IL-1β(ED7), of which the binding to preIL-1β was hindered by a polyclonal antibody against the mature domain of IL-1β Immunoprecipitation of limited proteolysed preIL-1β by ED7 suggested that the epitope for ED7 may not be localized at the junction between preIL-1β and mature IL-1β. We therefore examined the possibility that the pre-domain of IL-1β might interact with the mature domain by using chemical cross-linking. V8 protease yielded a mature 17. 5-kDa protein from untreated preIL-1β but not chemically cross-linked preIL-1β However, cleavage of the cross-link with 2-mercaptoethanol liberated a mature 17. 5-kDa protein from preIL-1β, suggesting that the pre-domains of IL-1β might interact with the mature domain. Similar phenomena were observed with preIL-1α Such an intermolecular interaction may inhibit or modulate the biological activity of mature IL-1s.View full abstractDownload PDF (4675K) -
Yasuo Ohnishi, Teruhiko Beppu, Sueharu Horinouchi1997 Volume 121 Issue 5 Pages 902-913
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSA serine protease (SSP) of Serratia marcescens is one of the extracellular enzymes secreted from this Gram-negative bacterium. SSP is produced as a large precursor and converted to a mature protein by cleavages removing an NH2-terminal signal sequence and a COOH-terminal pro-region. This COOH-terminal pro-region is integrated into the outer membrane and has a functional role for the export of the mature protein across the outer membrane. Southern hybridization analysis with a DNA fragment encoding the COOH-terminal pro-region as the probe showed a wide distribution of nucleotide sequences encoding SSP exporter-like proteins among Serratia species. Moreover, S. marcescens IFO 3046, from which the ssp gene had been cloned, was found to contain two ssp homologues (ssp-h1 and ssp-h2). They were cloned and their nucleotide sequences were determined. The two ssp homologues were found to exist in tandem on the genome and their amino acid sequences showed 81% identity to each other. Both of them showed 55% identity in amino acid sequence to preproSSP. In addition, both showed end-to-end similarity to the 100 kDa serotype-specific antigen (Ssa1) of Pasteurella haemolytica. Escherichia coli JM105 containing ssp-h1 gene produced a 53 kDa protein corresponding to the NH2terminal portion and a 49 kDa protein corresponding to the COOH-terminal portion, both of which were rigidly integrated in the outer membrane. Consistent with the significant similarity of the COOH-terminal portions of the homologues to that of SSP, they showed the ability to translocate the mature SSP part across the outer membrane into the medium. Furthermore, the NH2-terminal portion of the homologue was not translocated into the outer membrane without its COOH-terminal part. All of these data show that the SSP homologues are outer membrane proteins that are translocated into the outer membrane with the aid of the translocator function of their COOH-terminal part.View full abstractDownload PDF (8105K) -
Junichi Takagi, Takashi Isobe, Yoshikazu Takada, Yuji Saito1997 Volume 121 Issue 5 Pages 914-921
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSIntegrin activation and sebsequent ligand binding to it are regulated by intracellular mechanisms called inside-out signaling, which are not fully understood and are accompanied by dynamic structural changes of the integrin molecule itself. A monoclonal antibody recognizing a conformation-dependent epitope on humanβ1 integrin was produced and characterized in detail. This antibody, AG89, reacted with human integrin β1 chain regardless of the α subunit. AG89 can recognize resting state β1 integrin on the cells, but the reactivity is increased _??_2-fold upon integrin activation by activating anti-β1 antibodies and _??_3-fold by Mn2+. Furthermore, occupation of the ligand-binding pocket by a soluble ligand (RGD peptide for αvβ1 and CS-1 peptide for αvβ1) resulted in maximum binding of AG89, indicating that the epitope for AG89 is exposed during the conformational changes of β1 integrin upon activation/ligation. Epitope mapping by using interspecies chimeric β1 revealed that the epitope for AG89 lies within residues 426-587, which corresponds to the cysteine-rich repeat structure located in the middle of the β1 chain. The fact that binding of AG89 itself could activate the resting β1 integrin indicates that exposure of the AG89 epitope in the membrane-proximal stalk-like domain and “opening” of the ligand-binding pocket at the outermost domain are physically linked. We propose that the integrin “signaling” is mediated by this direct physical transduction of confor-mational information along the integrin molecule.View full abstractDownload PDF (2207K) -
Tsuyoshi Nishi, Kentaro Kubo, Masahisa Hasebe, Masatomo Maeda, Masamit ...1997 Volume 121 Issue 5 Pages 922-929
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSH+/K+-ATPase (composed of α and β subunits) and histamine H2 receptor are specifically expressed in gastric parietal cells. The GATA binding proteins (GATA-GT1 and GATA-GT2, also called GATA-6 and GATA-4, respectively) originally found in the gastric mucosa recognized a sequence motif [gastric motif, (G/C)PuPu(G/C)NGAT(A/T)PuPy] in the upstream regions of the ATPase genes [Tamura, S., Wang, X. -H., Maeda, M., and Futai, M. (1993) Proc. Natl. Acad. Sci. USA 90, 10876-10880]. These proteins activated the transcrip-tion of the reporter gene ligated downstream of the control region of the rat ATPase α or β subunit gene but had no effect on the same reporter ligated downstream of the H2 receptor gene. Deletion analyses suggested that the upstream 249 ( α gene) and 323 ( β gene) base pair sequences from the first letter of the initiation codon are sufficient for activation by the GATA proteins. Interestingly, two and three gastric motifs are located near the TATA-boxes of the α and β genes, respectively. Mutagenesis studies demonstrated that the two motifs proximal to the TATA-box sequences of the ATPase α and β subunit genes were essential for the activation. These results suggest that both the α and β subunit genes are regulated similarly by the GATA binding proteins. The expression system established in this study is a useful system for analyzing the roles of GATA proteins in transcriptional regulation of the H+K+-ATPase gene.View full abstractDownload PDF (3549K) -
Aiwu Zhou, Xueyuan Jiang, Fei Dou, Dexu Zhu, Xianxiu Xu1997 Volume 121 Issue 5 Pages 930-934
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSPlasminogen activator inhibitor 2 (PAI-2) is an important regulator of plasminogen activation, which inhibits both tissue-type plasminogen activator (tPA) and urokinase-type plasminogen activator (uPA). In this study we have developed a high-level expression system by inserting a modified PAI-2 gene downstream of the T7 promoter. The expression level of recombinant PAI-2 amounted to 55-60% of total microbial protein. By efficient renaturation and one-step purification, the recombinant protein was purified to homogene-ity. The specific activity and yieldof recombinant PAI-2 reached 33, 000 IU/mg and 10 mg per gram wet weight of Escherichia coli cells, respectively. The second-order rate constant for uPA was 2.6-2.8×106 M-1. s-1.View full abstractDownload PDF (1581K) -
Satoshi Nakagawa, Yuki Okaya, Kimio Yatsunami, Satoshi Tanaka, Hiroshi ...1997 Volume 121 Issue 5 Pages 935-940
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSPreviously, we reported the structure of human L-histidine decarboxylase gene. To identify the regions that regulate the tissue-specific expression of HDC, we constructed a fusion DNA with the 5'-flanking region from-1003 to +99 of the HDC gene and chloramphenicol acetyltransferase (CAT) gene, which was then transfected into human basophilic leukemia KU-812-F cells or human epithelial carcinoma HeLa cells. The 1102 by DNA fragment stimulated the CAT activity in KU-812-F cells, but not in HeLa cells. CAT analysis with a series of 5'- deletion constructs of the HDC-CAT gene revealed the existence of two positive and one negativeregulatory elements at -855 to -841 and -532 to -497 and -829 to -821, respectively. Sequence analysis showed a nuclear factor c-Myb binding motif, TAACTG, at position -520. Gel mobility shift analysis showed that the nuclear extract ofKU-812-F cells, but not that of HeLa cells, contains a factor which can bind to this motif. These results suggest that the 5-flanking region of the HDC gene contains multiple regulatory elements for HDC gene expression and that at least one element, including a c-Myb binding motif, is responsible for the tissue-specific expression of HDC.View full abstractDownload PDF (3267K) -
Kenji Mori, Sachiko Kii, Akihiko Tsuji, Masami Nagahama, Akiyoshi Imam ...1997 Volume 121 Issue 5 Pages 941-948
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSPACE4 is a processing protease which processes the precursor protein to the mature protein. Currently, four PACE4 isoforms have been reported [Tsuji, A. et al. (1994) Biochem. Biophys. Res. Commun. 200, 943-950] . In this study, we have cloned cDNA encoding a novel isoform, PACE4E, by screening the human brain cerebellum cDNA library and reverse transcriptase-polymerase chain reaction analysis of total RNA from human hepatoma HepG2 cells. The PACE4E cDNA encoded an amino acidsequence of 975 residues. The sequence from the amino terminus to Arg900 of PACE4E was identical to the correspond-ing sequence of PACE4A, but the carboxy terminal sequence (75 residues) was unique and contained a hydrophobic cluster (Leu952-Gly968). PACE4E cDNA was transiently transfected in COS-1 cells, and theexpressed proteins were a 112-kDa precursor form and a 105-kDa mature form. Theywere secreted into the culture medium, but their secretion was retarded compared with that of PACE4A. The expression of a mutant of PACE4E truncated up to thehydrophobic cluster from the carboxy terminus resulted in a remarkable increaseinsecretion level, suggesting that PACE4E tends to be retained intracellularly dueto interac-tion with the membrane through the hydrophobic cluster. On the contrary, thetransient expression experiment of PACE4C showed that only 68-kDa protein(precursor form) was detected in the cell and not secreted into the medium. Inaddition, coexpression experiment revealed that PACE4E was able to process the precursor form of von Willebrand factor to the mature form, but PACE4C did not process it.View full abstractDownload PDF (3606K) -
Noriko Tsujimoto, Kenji Kontani, Shin-ichi Inoue, Shin-ichi Hoshino, O ...1997 Volume 121 Issue 5 Pages 949-956
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSCD38 is a type II transmembrane glycoprotein possessing an NAD+ glycohydrolase activity in its extracellular domain. We previously reported that the ligation of CD38 by a monoclonal antibody (mAb), HB-7, induces the tyrosine phosphorylation of cellular proteins including p120c-cbl in differentiated human myeloid cell lines and that the phosphorylated p120c-cbl is capable of binding to phosphatidylinositol (PI) 3-kinase. In the present study, we found that the agonistic anti-CD38 mAb markedly potentiates superoxide generation stimulated by chemotactic formyl-Met-Leu-Phe receptors in the CD38-producing cells. HB-7 neither generated superoxide by itself nor enhanced the cell response induced by phorbol 12-myristate acetate, indicating that the potentiating action of the anti-CD38 mAb is specific for the stimulation by the GTP-binding protein (G1)-coupled membrane receptors. The potentiation by HB-7 was abolished by prior treatment of the cells with a tyrosine kinase inhibitor, pertussis toxin, or a potent PI 3-kinase inhibitor, wortmannin. 1113-7 also enhanced the product formation of PI 3-kinase in response to the chemotactic receptor stimulation, without significant changes in the receptor-stimulated accumulations of inositol-1, 4, 5-trisphosphate, arachidonate release, and intracellular Ca2+. These results indicate that the CD38-induced tyrosine phosphorylation has a cross-talk with the chemotactic receptor/G1-mediated signal transduction pathway resulting in the enhancement of superoxide generation, probably through the activation of PI 3-kinase.View full abstractDownload PDF (3823K) -
All Nejidat, Hagay Shmuely, Aharon Abeliovich1997 Volume 121 Issue 5 Pages 957-960
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSA technique for detection of the activity of hydroxylamine oxidoreductase (HAO) involving denaturing SDS-polyacrylamide gels was developed. The activity of HAO of Nitrosomonas europaea was assayed using this technique, which revealed a single active band of 140 kDa. The HAO activity of other ammonia-oxidizers was also resistant to SDS, the molecular weights being identical to that of N. europaea. N. europaea cells starved of ammonia for up to 72 h retained a considerable amount of HAO, as detected on Western blot analysis, and a significant level of its activity, as found on assaying at the end of the starvation period. Only after 4 h incubation of starved N. europaea cells with 2. 0 mM ammonia was some increase in the HAO level observed. The results indicate that HAO remains highly stable during ammonia starvation of N. europaea.View full abstractDownload PDF (3191K) -
Yin Kun Liu, Atsuko Nemoto, Yan Feng, Toshimasa Uemura1997 Volume 121 Issue 5 Pages 961-968
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe β peptide (113-125), derived from a conserved sequence of the β subunit of integrins, was synthesized to investigate its adhesive properties to matrix proteins and the effects on cell adhesion to immobilized fibronectin. In this study, weobserved that the biotinylated β peptide was able to bind efficiently to immobilized fibronectin, fibrinogen, collagen Type I and vitronectin with different degrees of affinity. It was also demonstrated that biotinylat-ed fibronectin or fibrinogen could bind to the coated β peptide. This kind of binding, which might be non-covalent linkage, was partially blocked by coincubation with the peptide GRGDS or EDTA, but not by SDGRG. Cell adhesion experiments were performed to study the effect of the β peptide. The data showed that the β peptide partially inhibitedboth fibroblast L929 and MC3T3-E1 osteoblastic cells from adhering to immobilized fibronectin in a dosage-dependent manner. In the presence of 100μM concentration of the β peptide, the inhibition rate of cell adhesion was 34% for fibroblast L929 cells and 54. 1% for MC 3T3-E1 osteoblastic cells. This research suggeststhat the β peptide might act independently as an adhesive region of the β subunitof integrins and may occupy the cell-binding site within fibronectin.View full abstractDownload PDF (4975K) -
Yutaka Yatomi, Yasuyuki Igarashi, Libo Yang, Nobuo Hisano, Ruomei Qi, ...1997 Volume 121 Issue 5 Pages 969-973
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSAlthough sphingosine 1-phosphate (Sph-1-P) is reportedly involved in diverse cellular processes and the physiological roles of this bioactive sphingolipid havebeen strongly suggested, few studies have revealed the presence of Sph-1-P in human samples, including body fluids and cells, under physiological conditions. In this study, we identified Sph-1-P as a normal constituent of human plasma andserum. The Sph-1-P levels in plasma and serum were 191 ± 79 and 484 ± 82 pmol/ml (mean ± SD, n=8), respectively. Furthermore, when Sph-1-P was measured in paired plasma and serum samples obtained from 6 healthy adults, the serum Sph-1-P/plasma Sph-1-P ratio was found to be 2.65 ± 1.26 (mean ± SD). It is most likely that the source of discharged Sph-1-P during blood clotting is platelets, because platelets abundantly store Sph-1-P compared with other blood cells, and release part of their stored Sph-1-P extracellularly upon stimulation. We also studied Sph-1-P-related metabolism in plasma. [3H] Sph was stable and not metabolized at all in plasma, but was rapidly incorporated into platelets and metabolized mainly to Sph-1-P in platelet-rich plasma. [3H] Sph-1-P was found to be unchanged in plasma, revealing that plasma does not contain the enzymes needed for Sph- 1-P degradation. In summary, platelets can convert Sph into Sph-1-P, and are storage sites for the latter in the blood. In view of the diverse biological effects of Sph-1-P, the release of Sph-1-P from activated platelets may be involved in a variety of physiological and pathophysiological processes, including throm-bosis, hemostasis, atherosclerosis and wound healing.View full abstractDownload PDF (3104K) -
Atsushi Yamamoto, Tadaoki Hara, Koji Tomoo, Toshimasa Ishida, Tomomi F ...1997 Volume 121 Issue 5 Pages 974-977
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe binding mode of CA074 [N-(L-3-trans-propylcarbamoyl-oxirane-2-carbonyl)-L-isoleucyl-L-proline], a specific irreversible inhibitor, to bovine spleen cathepsin B was elucidated by X-ray crystal structure analysis of the complex at 2.2 Å resolution (conventional R=0.185). Inconsistently with our model used for the development of CA074, the L-isoleucyl-L-proline and propylcarbamoyl moieties are located at the S' and S subsites, respectively. This unexpected binding is primarily due to (i) similar extended chain conformations (due to the same S configurations) at the oxirane C2 and C3 atoms of CA074 and (ii) the just fit formation of double hydrogen bonds between the carboxyl oxygens of L-proline and the imidazole nitrogens of His-110 and His-111 residues (these residues are missing inpapain, the tertiary structure of which was used for the design of CA074). The oxirane C3 atom possessing the P' substituent is covalently bound to the Cys-29 Sγ atom (C3-Sγ=1.79 Å) and the S configuration is maintained. The present result will provide useful information for characterizing the substrate-specificity of cathepsin B.View full abstractDownload PDF (2277K) -
Hidenori Hayashi, Masanori Hara1997 Volume 121 Issue 5 Pages 978-983
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSThe origin of the 1-alkenyl group of ethanolamine plasmalogen was investigated. Three candidates were examined for the fatty alcohol forming the 1-alkenyl group. [1-14C]Hexadecanoic acid, [1-14C]hexadecanol, or [1-14C] lignoceric acid was administered to rats treated with 0.25% clofibrate-chow for 2 weeks. At 0.5, 1, 2, 3, and 4h after administration of the radiolabeled compound, rats were killed and ethanolamine-containing phosphoglyceride (EPG)-rich fraction was isolated from the liver. The components of the 1-radyl group in EPG-rich fraction were separated and the radioactivity was determined. The radiolabel after administration of [1-14C] hexadecanoic acid or [1-14C] hexadecanol was almost wholly incorporated into diacyl-type glycerophosphoethanolamine (GPE), and was predominantly found in hexadecanoic acid fraction. Therefore, the long-chain fatty acid may be incorporated intact into the diacyl groups, and the long-chain fatty alcohol may be similarly incorporated after oxidation to the acid. In contrast, the radiolabel after the administration of [1-14C]lignoceric acid was found in the 1-alkenyl group of ethanolamine plasmalogen. After hydrolysis of the 1-alkenyl group by treatment of the plasmalogen with HCl vapor, the radiolabeled products were chiefly stearaldehyde and palmitaldehyde. The above data indicate that nascent fatty alcohol de novo synthesized from acetyl-CoA derived by peroxisomal β-oxidation is almost exclusively used as the fatty alcohol forming the 1-alkenyl group of ethanolamine plasmalogen.View full abstractDownload PDF (1847K) -
S. Ramachandiran, D. Takezawa, W. Wang, B. W. Poovaialf1997 Volume 121 Issue 5 Pages 984-990
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSA novel calcium-binding calcium/calmodulin-dependent protein kinase (CCaMK) with a catalytic domain, calmodulin-binding domain, and a neural visinin-like domain was cloned and characterized from plants [Patil et al., (1995) Proc. Natl. Acad. Sci. USA 92, 4797-4801; Takezawa et al. (1996) J. Biol. Chem. 271, 8126-8132]. The mechanisms of CCaMK activation by calcium and calcium/calmodulin were investigated using various deletion mutants. The use of deletion mutants of CCaMK lacking either one, two, or all three calcium-binding EF hands indicated that all three calcium-binding sites in the visinin-like domain were crucial for the full calcium/calmodulin-dependent kinase activity. As each calcium-binding EF hand was deleted, there was a gradual reduction in calcium/calmodu-lin-dependent kinase activity from 100 to 4%. Another mutant (amino acids 1-322) which lacks both the visinin-like domain containing three EF hands and the calmodulin-binding domain was constitutively active, indicating the presence of an autoinhibitory domain around the calmodulin-binding domain. By using various synthetic peptides and the constitutively active mutant, we have shown that CCaMK contains an autoinhibitory domain within the residues 322-340 which overlaps its calmodulin-binding domain. Kinetic studies with both ATP and the GS peptide substrate suggest that the autoinhibitory domain of CCaMK interacts only with the peptide substrate binding motif of the catalytic domain, but not with the ATP-binding motif.View full abstractDownload PDF (2926K) -
Ming-Juan Luo, Wu-Yuan Lu, Cheng-Wu Chi1997 Volume 121 Issue 5 Pages 991-995
Published: 1997
Released on J-STAGE: November 18, 2008
JOURNAL FREE ACCESSAn uncertain intron of 87 bp within the cDNA sequences of arrowhead proteinase inhibitorsA and B was clarified. By site-directed mutation with either a stop codon inside theuncertain intron or mutated codons at both its 5' and 3' ends, it was proved that there wasneither a translation intron nor a protein intron present in the cDNA sequences ofproteinase inhibitors A and B. The primary structure of inhibitor B was then reexaminedby mass spectrometry molecular weight determination and partial amino acid sequencing. A 38 residue peptide was derived by degradation of inhibitor B with lysylendopeptidase, and purified, which was not found in the previous work, and its N-terminal part was noneother than the missed 29 residue peptide encoded by the uncertain intron. The 38 residuepeptide was very hydrophobic, while the 29 residue peptide it included was even morehydrophobic. The N-terminal part of the missed peptide was also aligned within aBrCN-degraded fragment of the inhibitor. In this paper the cause of the overlooking of this29 residue peptide in the previous work and some unexpected problems which arose duringthe former sequence analysis are explained.View full abstractDownload PDF (500K)
- |<
- <
- 1
- >
- >|