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M Shiraiwa

Publications and source records attributed to M Shiraiwa.

At least 19 recordsLinked to original sources
PubMed2006

Molecular cloning and characterization of a novel salt-inducible gene encoding an acidic isoform of PR-5 protein in soybean (Glycine max [L.] Merr.).

We identified a novel salt-inducible soybean gene encoding an acidic-isoform of pathogenesis-related protein group 5 (PR-5 protein). The soybean PR-5-homologous gene, designated as Glycine max osmotin-like protein, acidic isoform (GmOLPa)), encodes a putative polypeptide having an N-terminal signal peptide. The mature GmOLPa protein without the signal peptide has a calculated molecular mass of 21.5 kDa and a pI value of 4.4, and was distinguishable from a known PR-5-homologous gene of soybean (namely P21 protein) through examination of the structural features. A comparison with two intracellular salt-inducible PR-5 proteins, tobacco osmotin and tomato NP24, revealed that GmOLPa did not have a C-terminal extension sequence functioning as a vacuole-targeting motif. The GmOLPa gene was transcribed constitutively in the soybean root and was induced almost exclusively in the root during 24 h of high-salt stress (300 mM NaCl). Interestingly, GmOLPa gene expression in the stem and leaf, not observed until 24 h, was markedly induced at 48 and 72 h after commencement of the high-salt stress. Abscisic acid (ABA) and dehydration also induced expression of the GmOLPa gene in the root; additionally, dehydration slightly induced expression in the stem and leaf. In fact, the 5'-upstream sequence of the GmOLPa gene contained several putative cis-elements known to be involved in responsiveness to ABA and dehydration, e.g. ABA-responsive element (ABRE), MYB/MYC, and low temperature-responsive element (LTRE). These results suggested that GmOLPa may function as a protective PR-5 protein in the extracellular space of the soybean root in response to high-salt stress and dehydration.

Amino Acid Sequence↗
PubMed2000

Human peptidylarginine deiminase type III: molecular cloning and nucleotide sequence of the cDNA, properties of the recombinant enzyme, and immunohistochemical localization in human skin.

Peptidylarginine deiminase catalyzes the post-translational modification of proteins through the conversion of arginine to citrulline in the presence of calcium ions. In rodents, peptidylarginine deiminase has been classified into four isoforms, types I, II, III, and IV, which are distinct in their molecular weights, substrate specificities, and tissue localization. Of these isoforms, only type III was detected in epidermis and hair follicles. Although the role of this enzyme in these tissues is not yet clear, indirect data have shown that several structural proteins such as filaggrin, trichohyalin, and keratin are substrates for peptidylarginine deiminase. In this study, we cloned the full-length cDNA of human peptidylarginine deiminase type III (3142 bp) from cultured human keratinocytes by reverse transcription-polymerase chain reaction and by rapid amplification of cDNA ends methods. This cDNA contained a 1995 bp open reading frame encoding 664 amino acids (Mr = 74 770). To explore the physicochemical and enzymatic properties of human peptidylarginine deiminase type III, we constructed a plasmid for producing a recombinant human peptidylarginine deiminase type III in bacteria. The enzymatic characteristics of the recombinant enzyme were very similar to those of the rodent peptidylarginine deiminase type III. The recombinant enzyme showed the catalytic activities toward structural proteins of epidermis and hair follicle, filaggrin and trichohyalin, in which the deiminations maxima of about 60% and 13% arginine residues were observed in filaggrin and trichohyalin, respectively. An immunohistochemical study of human scalp skin with a monospecific anti-peptidyl-arginine deiminase type III antibody revealed that the type III enzyme was localized to the inner root sheath and outer root sheath of hair follicles. Peptidylarginine deiminase type III in the inner root sheath was notable between supramatrix and keratogenous zone and was scarcely detected in cornified hair zone. The enzyme was also expressed in the cuticle layer of hair. On the other hand, expression of the enzyme in the epidermis was very low. These data imply that human peptidylarginine deiminase type III is the predominant isoform in hair follicles and may function as a modulator of hair structural proteins, including trichohyalin during hair and hair follicle formation.

Amino Acid Sequence↗
PubMed2000

Inflammatory pseudotumor of the spleen: a case report.

We report on an inflammatory pseudotumor of the spleen. A 72-year-old woman visited our hospital complaining of nausea. Physical examination and laboratory investigations were unremarkable. Ultrasonography, computed tomography, magnetic resonance imaging and angiography showed a hypovascular splenic mass measuring about 5 cm in diameter with a calcification in the center of the lesion. Splenectomy was performed. The removed spleen, weighing 145 g, contained a tan-white, circumscribed mass, measuring 6.2 x 5.5 x 5.3 cm. Histologically, the splenic mass was composed of an admixture of inflammatory cellular elements, predominantly plasma cells and lymphocytes with hyalinization, fibrosis, lymph follicles and multinuclear giant cells, suggestive of a inflammatory pseudotumor. The patient is currently alive and asymptomatic, 24 months after surgery. Inflammatory pseudotumors of the spleen are extremely rare and only 39 cases have been reported in the medical literature.

Aged↗
PubMed1999

Molecular cloning of cDNAs of mouse peptidylarginine deiminase type I, type III and type IV, and the expression pattern of type I in mouse.

Peptidylarginine deiminases (PADs), a group of post-translational enzymes, catalyze the conversion of protein-bound arginine residues to citrulline residues in a calcium ion-dependent manner and are widely distributed in various organs of vertebrates. Although the existence of four isoforms of PAD (types I, II, III, and IV) is reported in rodents, the relative functions of the isoforms with respect to their colocation in the tissues have yet to be explored. In this study, we cloned the full-length cDNA encoding mouse PAD type I by screening a uterine cDNA library and using the RACE method. This cDNA consists of an open reading frame of 1989 bases encoding 662 amino acids (73,823 Da), a 5'-untranslated region of 127 bases and a 3'-untranslated region of 1639 bases. Comparative reverse transcription-PCR and Northern-blot analyses detected PAD type I mRNA only in the epidermis and uterus. Administration of estrogen to adult ovariectomized mice increased the content of PAD type I mRNA in the uterus, providing evidence that its expression is under the control of the sex steroid hormone. We also cloned the full-length cDNAs of mouse PAD type III and type IV by the reverse transcription-PCR and RACE methods. The primary structure of PAD type III contains 664 amino acids (75,098 Da) deduced from the coding region of 1995 bases, and the primary structure of PAD type IV consists of 666 amino acids (74,475 Da) deduced from the coding region of 2001 bases. Comparison of the deduced amino acid sequences of all four isoforms of PAD showed about 50% identity with each other, the 3' regions being highly homologous compared with the 5' regions.

Amino Acid Sequence↗
PubMed1998

Cloning of cDNA encoding a novel isoform (type IV) of peptidylarginine deiminase from rat epidermis.

We isolated a new clone that showed structural similarities with the rat peptidylarginine deiminase (PAD) types II and III. The full-length cDNA sequence of this novel PAD comprised 1998 bp encoding a sequence for 666 amino acid residues (Mr 74467), a 3'-non-coding region of 115 bp and a 5'-non-coding region of 16 bp. The derived amino acid sequence of the PAD showed 51.1 and 54.0% identities with the sequences of types II and III, respectively. Semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) assays of mRNAs from several tissues of rat indicated that the PAD message is highly expressed in the pancreas, spleen, and ovary and, less strongly expressed in the liver, lung, stomach, kidney, uterus, and dermis, and weakly expressed in the brain, heart and epidermis. Since this expression pattern was quite different from those of the previously reported PAD types I, II, and III, we designated this novel PAD as type IV.

Amino Acid Sequence↗
PubMed1998

Studies on agents with vasodilator and beta-blocking activities. V. Synthesis and pharmacological activity of the optical isomers of TZC-5665.

Synthesis of the four optical isomers of TZC-5665 (1), a candidate for the treatment of congestive heart failure, was achieved by the reaction of chiral diaminopyridazinone (2) with chiral glycidyl ether. (3). The hypotensive and beta-blocking activities of 1 and its optical isomers were examined when given intravenously into anesthetized rats. Furthermore these compounds were evaluated for inhibitory activity on cAMP phosphodiesterase III. Among the four optical isomers, Ra,Sb-one (1c) possessed the essential activities of TZC-5665 (1).

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1997

Stimulation of human keratinocyte growth by alginate oligosaccharides, a possible co-factor for epidermal growth factor in cell culture.

Oligosaccharides, involved in regulation of plant developmental and defensive processes, were tested to determine their ability to enhance proliferation of human keratinocytes. A mixture of alginate oligosaccharides remarkably stimulated keratinocyte growth and [3H]thymidine uptake in the presence of epidermal growth factor (EGF). The activity was comparable to bovine pituitary extract, a common complement in keratinocyte culture, and additive on BPE-induced stimulation. The most effective oligosaccharide in the mixture was identified and its chemical structure was determined. These findings demonstrate a novel activity of alginate oligosaccharide(s) in keratinocyte growth and suggest a possible co-factor for EGF-dependent stimulation in medium for keratinocytes.

Alginates↗
PubMed1997

Isolation and molecular cloning of epidermal- and hair follicle-specific peptidylarginine deiminase (type III) from rat.

Peptidylarginine deiminase (PAD) is a post-translational 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.

Amino Acid Sequence↗
PubMed1995

Expression of mouse uterine peptidylarginine deiminase in Escherichia coli: construction of expression plasmid and properties of the recombinant enzyme.

To study the structure/function relationships of peptidylarginine deiminase (PAD), we constructed an Escherichia coli expression plasmid for mouse uterine PAD. First, segments of a cDNA encoding murine PAD were subcloned into a single plasmid, and the resulting plasmid, pKSPAD1, was inserted into an expression vector, pKK223-3, at the EcoRI and HindIII restriction sites. Since no detectable amount or activity of the PAD was produced by E. coli carrying that plasmid, the 5'-untranslated sequence of the cDNA was replaced with several synthetic DNAs. One of the constructed plasmids, pKKPAD4, which had a unique DNA linker containing a pair of Shine-Dalgarno sequences and a short preceding cistron inserted into the adjacent 5'-region of the coding region, produced a large quantity of mouse PAD as an unfused protein in E. coli. The purified recombinant PAD was indistinguishable from the native enzyme with respect to some structural properties, such as molecular mass, amino- and carboxyl-terminal sequences, and circular dichroism spectra. However, the alpha-amino group of the amino-terminal methionine residue of the recombinant PAD was not acetylated as was that of the native enzyme. Comparison of the recombinant PAD with the natural enzyme did not indicate significant differences in their sensitivity to activation by Ca2+ and in their substrate specificity toward arginine derivatives. The rates of modification of soybean trypsin inhibitor (Kunitz) were also similar for the recombinant and native PADs. These results indicate that the recombinant PAD has biological activities identical to those of the native enzyme and that the N alpha-acetyl group in the native PAD does not appear to have any particular role in the enzyme's catalytic function.

Amino Acid Sequence↗
PubMed1995

Mouse uterus peptidylarginine deiminase is expressed in decidual cells during pregnancy.

Peptidylarginine deiminase is localized in the cytosol of the luminal and glandular epithelia of the nonpregnant murine uterus and its expression is regulated by sex hormones [Takahara et al., [1989]: J Biol Chem 264, 13361-13368; Takahara et al. [1992]: J Biol Chem 267,520-525]. Here, we demonstrate that changes occur in the enzyme level in the mouse uterus during pregnancy and parturition. After a rapid decrease in enzymatic activity from day 1 to day 5 of pregnancy, the activity sharply increased during the middle stage of pregnancy (day 8 to day 10) and then gradually decreased during late pregnancy. Expression of the enzyme occurred only in the decidual cells that had differentiated from endometrial stroma cells surrounding the implantation site. The immunochemical properties of the enzyme expressed in the decidualized cells was indistinguishable from those in the uterine epithelia. These results suggest that peptidylarginine deiminase has important roles in decidual cells and not just in the epithelia of the nonpregnant uterus. Moreover, the level of enzyme activity increased slightly just before parturition (day 17), and then decreased during the 12 h period after parturition. The tissue localization of the enzyme expressed around the time of parturition changed from decidua to the luminal and glandular epithelia. Semiquantitative analyses of the enzyme mRNA content in the pregnant uteri showed a remarkable increase from day 7 leading to the onset of the enzyme synthesis in the decidual cells. After reaching the maximal level at day 12, small peaks in the mRNA level were observed at two times during late pregnancy. Since these serial changes in the mRNA level did not correlate with changes in sex hormones, the expression of decidual peptidylarginine deiminase seemed to be controlled by factors other than sex hormones.

Animals↗
PubMed1995

Existence and differential changes of peptidylarginine deiminase type II in mouse yolk-sac erythroid cells.

Peptidylarginine deiminase (PAD) catalyzes the conversion of arginyl residues in proteins to citrullyl residues in the presence of Ca2+. Recently, we obtained a monoclonal antibody, EH7, which reacted only with mouse PAD type II. Here, we describe immunohistochemical findings on the cellular localization of PAD type II in mouse fetus by using the monoclonal antibody. PAD type II is expressed in yolk-sac erythroid cells and the level of the enzyme in these cells decreases as the cells differentiate.

Animals↗
PubMed1995

Aggregated form of dextransucrases from Leuconostoc mesenteroides NRRL B-512F and its constitutive mutant.

Purified dextransucrases [EC 2.4.1.5], DSW-D and DSW-G, from Leuconostoc mesenteroides B-512F were obtained from affinity chromatography with DEAE-Sephadex A-50 by elution with clinical dextran and guanidine-HCl, respectively. DSM-G was purified from the B-512F mutant strain SH 3002, which produces dextransucrase constitutively. Although the sugar contents of the purified enzymes were different, their molecular masses by SDS-PAGE were all 170 kDa. DSW-D and DSW-G were highly aggregated and the all the activities were eluted at the void volume (V0) on Sepharose 6B, while the DSM-G was eluted at 1.2 x V0 volume. On rechromatography, DSM-G was separated into three peaks corresponding to the aggregated form, monomeric form, and partially digested form, respectively. The aggregation of Leuconostoc dextransucrase was looser than that of streptococcal glucosyltransferases, but the structures of these enzymes had high homology with each other.

Amino Acid Sequence↗
PubMed1994

Production and epitope specificity of monoclonal antibody against mouse peptidylarginine deiminase type II.

Peptidylarginine deiminase catalyzes the conversion of arginyl residues in proteins to citrullyl residues in the presence of Ca2+. We described the preparation of monoclonal antibody (subclass type IgG1) specific to mouse peptidylarginine deiminase type II. The antibody had no effect on the enzyme activity and its specific epitope was localized in the eight-residue segment at the amino-terminal portion of the enzyme.

Amino Acid Sequence↗
PubMed1993

An active-site peptide containing the second essential carboxyl group of dextransucrase from Leuconostoc mesenteroides by chemical modifications.

The treatment of Leuconostoc mesenteroides B-512F dextransucrase with 10 mM 1-ethyl-3-[3-(dimethylamino)propyl]carbodiimide (EDC) and glycine ethyl ester (GEE) inactivated the enzyme almost completely within 24 min where the modification of one carboxyl group/mol of the enzyme by EDC was attained. Though 30 mM diethyl pyrocarbonate (DEP) also inactivated the enzyme, about 35% of the activity remained during a 36-min incubation. When 10 mol of imidazole residues/mol of the enzyme was modified by DEP, 50% of the activity was still retained. The addition of the substrate sucrose greatly retarded the enzyme inactivation by EDC. However, the addition of dextran slightly protected the inactivation of the glucosyl-transferring activity and accelerated the inactivation of the sucrose-cleaving activity. In the case of DEP, the addition of sucrose or dextran gave no influence on the inactivation of the enzyme. Therefore, the carboxyl group seemed to play a more important role in the substrate binding and in the catalytic activity of the dextransucrase than the imidazolium group. Differential labeling of Leuconostoc dextransucrase by EDC was conducted in the presence of a sucrose analog, sucrose monocaprate. The fluorescent probe N-(1-naphthyl)ethylenediamine (EDAN) was used as the nucleophile instead of GEE. A fluorescent labeled peptide was isolated from a trypsin digest of the EDC-EDAN modified enzyme. The amino acid sequence of the isolated peptide was Leu-Gln-Glu-Asp-Asn-Ser-Asn-Val-Val-Val-Glu-Ala.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1991

Composition and structure of "group B saponin" in soybean seed.

The composition of "group B saponin" in soybean seed was analyzed by HPLC, and six kinds of "group B saponin," named Ba, Bb, Bb', Bc, Bd and Be according to elution order from HPLC, were detected. Of these saponins, Ba, Bb, Bb' and Bc were identified with soyasaponin V, I, III and II, respectively. Bd and Be were novel saponins possessing soyasapogenol E as the aglycone and the same sugar chain as Ba and Bb, respectively. These saponins were very unstable in the isolated state and had a tendency to form Ba and Bb, respectively. From these results, Bd and Be are presumed to be the precursors of Ba and Bb in soybean seed.

Chromatography, High Pressure Liquid↗
PubMedDate not supplied

Cervical carcinoma: efficacy of thin-section oblique axial T2-weighted images for evaluating parametrial invasion.

BACKGROUND: To investigate the efficacy of thin-section oblique axial T2-weighted images in the assessment of parametrial invasion by cervical carcinoma. METHODS: One hundred parametria of 50 patients with cervical carcinoma were evaluated with pathologic correlation. We compared the sensitivity, specificity, and diagnostic accuracy in the assessment of parametrial invasion by cervical carcinoma between axial T2-weighted images and thin-section oblique axial T2-weighted images. RESULTS: Thin-section oblique axial T2-weighted images provided accurate cross sections of the cervix with excellent detail and detected parametrial invasion more accurately than did axial T2-weighted images showing cross sections of the trunk. Although the sensitivity, specificity, and accuracy for parametrial invasion were 46.4%, 91.7%, and 79.0%, respectively, on axial T2-weighted images, the corresponding values were 67.9%, 97. 2%, and 89.0%, respectively, on thin-section oblique axial T2-weighted images. There were statistically significant differences in the sensitivity (p = 0.014), specificity (p = 0.046), and accuracy (p = 0.002) in detecting parametrial invasion between these two types of images. CONCLUSIONS: Thin-section oblique axial T2-weighted images are useful for the assessment of parametrial invasion by cervical carcinoma.

Adenocarcinoma↗