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T Miyata

Publications and source records attributed to T Miyata.

At least 577 records · Page 32Linked to original sources
PubMed1988

Regulated expression of a gene encoding a nuclear factor, IRF-1, that specifically binds to IFN-beta gene regulatory elements.

Expression of the interferon-beta (IFN-beta) gene is induced by a variety of agents, including viruses. Evidence has been provided that a mouse nuclear factor, termed interferon regulatory factor-1 (IRF-1), specifically binds to the upstream regulatory region of the human IFN-beta gene and mediates virus-induced transcription of the gene. In this study, we describe the molecular cloning and characterization of the mouse and human cDNAs encoding IRF-1. Our results suggest that IRF-1 is also involved in the regulation of other genes such as IFN-alpha and MHC class I genes. Surprisingly, IRF-1 gene expression is dramatically induced by Newcastle disease virus in mouse L929 cells and by Concanavalin A in spleen cells. We show here that the IRF-1 gene possesses virus-inducible promoter.

Amino Acid Sequence↗
PubMed1988

Isolation of cDNA clones of human argininosuccinate lyase and corrected amino acid sequence.

In the present study, we isolated clones of human argininosuccinate lyase (ASL) cDNA from a liver cDNA library using a clone of rat ASL cDNA and analyzed human ASL cDNA nucleotide sequence. The results reveal that the sequence of human ASL cDNA published by O'Brien et al. in 1986 [Proc. Natl. Acad. Sci USA 83, 7211-7215] had one-base deletions at three independent positions in the coding regions near the COOH-terminus, which caused frame-shift variations in the amino acid sequence. Amino acid sequencing of peptides prepared from purified human liver ASL showed our predicted amino acid sequence to be correct.

Amino Acid Sequence↗
PubMed1988

Localization of the pyridoxal phosphate binding site at the COOH-terminal region of erythrocyte band 3 protein.

A human erythrocyte Band 3 peptide, affinity labeled with pyridoxal phosphate, was purified by a combination of gel permeation and reverse-phase high performance liquid chromatography. The amino acid sequence of the transmembrane peptide was determined by sequencing subfragments of the peptide obtained from lysyl endopeptidase and staphylococcal proteinase V8 digestions. When a peptide containing the COOH-terminal of human erythrocyte Band 3 was also purified and sequenced, the affinity-labeled peptide was found to be located close to the COOH-terminal of Band 3, where it could be aligned with amino acid residues 852-927 of a murine erythrocyte Band 3, deduced from a nucleotide sequence of a cDNA clone (Kopito, R. R., and Lodish, H. F. (1985) Nature 316, 234-238). The amino acid sequence of the COOH-terminal region was highly homologous to that of murine Band 3. As a result, the sequence of the COOH-terminal peptide of Band 3 was established as follows. (Formula: see text). The pyridoxal phosphate binding site was identified as Lys-18 which corresponded to Lys-869 of the deduced sequence. It appears that the COOH-terminal region of Band 3 constitutes at least a part of the active center for anion transport in human erythrocyte membranes.

Amino Acid Sequence↗
PubMed1988

The structure of brain-specific rat aldolase C mRNA and the evolution of aldolase isozyme genes.

The cDNA clones for rat aldolase C mRNA having the nearly complete length were isolated from a rat brain cDNA library and sequenced. The nucleotide sequence of pRAC2-1, a cDNA clone having the largest cDNA insert, indicates that the cDNA is composed of a 105-base-pair 5'-noncoding sequence, a 1089-base-pair coding-sequence and a 382-base-pair 3'-noncoding sequence. The amino acid sequence of aldolase C deduced from a possible open reading frame was composed of 362 residues having a relative molecular mass of 39,164 excluding the initiating methionine, one amino acid shorter than aldolases A and B. The length of aldolase c mRNA was 1750 residues, somewhat longer than that of the aldolase A and B transcripts. The aldolase C mRNA was distributed mainly in the brain, some in ascites hepatoma and fetal liver. Comparison of the amino acid sequences of rat aldolase C with those for rat aldolase A and B [Joh et al. (1985) Gene 39, 17-24; Tsutsumi et al. (1984) J. Biol. Chem. 259, 14572-14575], which have been determined previously, shows the existence of highly conserved stretches of amino acid among the three isozymic forms throughout their sequences. The extent of the homology between aldolases A and C is 81%, while those between aldolases A and B, and B and C are 70%, respectively. The analysis of amino acid substitution among aldolases A, B and C from several species suggests that the isozyme genes diverged much earlier than animal species appeared and that the aldolase C gene has evolved from the aldolase A gene after aldolase A and B genes diverged.

Amino Acid Sequence↗
PubMed1988

Molecular cloning of the cDNA of human X chromosomal gene (CCG1) which complements the temperature-sensitive G1 mutants, tsBN462 and ts13, of the BHK cell line.

The tsBN462 cell line, a temperature-sensitive (ts) mutant isolated from the hamster cell line, BHK21/13 has a ts defect in G1 progression and belongs to the same complementation group as the ts13 cell line. We cloned human cDNA which can complement both tsBN462 and ts13 mutations, from the cDNA library of the secondary ts+ transformant (K-1-1) of tsBN462 cells using, as a probe, the isolated human X chromosomal genomic DNA. The cloned DNA is 5.3 kb long and has an open reading frame of 4662 bp, encoding a protein of 178,768 daltons. The putative protein is hydrophilic with a tandem repeat of 120 amino acids in the C-terminal region. An amino acid sequence (PPKKKRRV), similar to the consensus sequence for the nuclear translocation signal, is located immediately before the tandem repeat of amino acids.

Amino Acid Sequence↗
PubMed1988

Effect of alpha 2-adrenoceptor antagonist on platelet activation during insulin-induced hypoglycaemia in type 2 (non-insulin-dependent) diabetes mellitus.

The role of epinephrine in platelet activation and the effect of an alpha 2-adrenoceptor antagonist, midaglizole, during insulin-induced hypoglycaemia in Type 2 (non-insulin-dependent) diabetes mellitus were examined. The action of midaglizole as a platelet alpha 2-antagonist was confirmed by in vitro studies using platelet-rich plasma and washed platelet suspension. Hypoglycaemia was induced by a bolus injection of short-acting insulin in 24 diabetic patients. They were divided into two groups, a control group (n = 12) and an alpha 2-group (n = 12), and midaglizole was administered orally 60 min before insulin injection in the latter. Blood glucose and plasma C-peptide levels were significantly decreased (p less than 0.005) by insulin injection in both groups. Counter-regulatory hormones, including epinephrine, and arginine vasopressin were similarly increased at the hypoglycaemic nadir compared with the levels at 0 min in both groups. Plasma beta-thromboglobulin was increased at the hypoglycaemic nadir (165.5 +/- 12.6 ng/ml) compared with the level at 0 min (121.0 +/- 11.5, p less than 0.005) in the control group, whereas no significant increase was demonstrated in the alpha 2-group. These results suggest that plasma epinephrine plays an important role in platelet activation during hypoglycaemia in Type 2 diabetes mellitus, and that the platelet activation is prevented by alpha 2-adrenoceptor antagonist.

Arginine Vasopressin↗
PubMed1988

Further evidence for H-2-unrestricted induction of minor histocompatibility antigens-specific T cell immunity in vivo.

Antigenic requirements for inducing minor histocompatibility antigens (MIHA)-specific T cell immunity for second set rejection (SSR) of a MIHA-allogeneic tumor were studied. An intravenous injection of surprisingly small numbers (10(4)-10(5] of live allogenetic spleen cells (SC) effectively primed mice for SSR of the allogeneic tumor, and this immunity was developed as early as 2-3 days after injection of the SC. In contrast, sonication-disrupted allogeneic SC, which should be readily processed by host antigen presenting cells (APC), were not active as immunogens, even at a dose 1000 times higher than the minimum effective dose of live SC. The possibility that host APC preferentially receive MIHA antigens shed by live allogeneic SC for T cell activation was ruled out. These results demonstrated that antigen processing via conventional pathways is very little involved in the mechanism of T cell activation. Under such restricted experimental conditions, the induction phase but not the effector phase of the MIHA-specific T cell immunity was shown to be H-2-unrestricted.

Animals↗
PubMed1988

Biosynthesis and localization of rat liver microsomal carboxyesterase E1.

One of the microsomal carboxyesterases, carboxyesterase E1, was purified from rat liver to homogeneity. Carboxyesterase E1 is a glycoprotein of high mannose type, and is composed of three identical subunits of 59 kDa each. It is very similar to "esterase pI 6.0" described by Menthein et al. (Arch. Biochem. Biophys. 200, 547-559 (1980)) in molecular weight, amino acid composition, and enzymic activities. Carboxyesterase E1 was found to be evenly distributed between rough and smooth microsomes. The content of the enzyme in microsomes was about 1.5% of total microsomal protein. It was exclusively located on the luminal side of microsomes, and was not detected immunologically in Golgi fractions or serum. In vitro translation of rat liver RNA by reticulocyte lysate showed that carboxyesterase E1 was synthesized preferentially on the bound ribosomes, as a precursor peptide larger than the peptide of the mature enzyme. Carboxyesterase E1 was solubilized from microsomes by treatment with low concentrations of detergents. However, it was not released from microsomes by treatment with a synthetic peptide which made the microsomal membrane permeable to soluble protein molecules. Carboxyesterase E1 is not a soluble luminal protein, and seems to be bound to the luminal surface of the membrane.

Amino Acids↗
PubMed1988

Bovine high-molecular-weight kininogen: a revision of the amino acid sequence of the light chain portion.

The amino acid sequence of the COOH-terminal light chain portion of bovine high-molecular-weight kininogen (HMWK) was reinvestigated, since some discrepancy of the amino acid sequence, which we reported previously, was found in the cDNA analysis for bovine HMWK (Kitamura, N. et al. (1983) Nature 305, 545-548). The results showed that the following positions in the light chain should be revised: Gln-23 to Glu, the sequence Asp-Asp-Asp-Trp-Ser at positions 62-66 to Ser-Asp-Asp-Asp-Trp, Asp-102 to Asn, and Gln-109 to Glu.

Amino Acid Sequence↗
PubMed1988

A new trisaccharide sugar chain linked to a serine residue in bovine blood coagulation factors VII and IX.

A new trisaccharide sugar chain was identified in bovine blood coagulation factors VII and IX. A pentapeptide isolated from factor VII contained Ser-52, which could not be identified with a gas-phase sequencer, suggesting an unknown substituent on the serine residue (Takeya, H. et al. (1988) J. Biol. Chem., in press). The same results were obtained for a pentapeptide containing Ser-53 of factor IX. Component sugar analysis revealed that the peptide contained 1 mol of glucose and 2 mol of xylose. This sugar component was also confirmed by high-resolution fast atom bombardment mass spectrometric analysis of the pentapeptide. The trisaccharide was released from the peptides by means of beta-elimination reaction and its reducing end was coupled with 2-aminopyridine. The fluorescent pyridylamino (PA-) derivative of the trisaccharide was purified by gel-filtration and reversed-phase HPLC. The sugar composition of the PA-trisaccharide was found to be 2 mol of xylose and 1 mol of PA-glucose. These results indicate the existence of a (Xyl2)Glc-Ser structure in factors VII and IX.

Amino Acids↗
PubMed1988

Blood clotting factor IX Niigata: substitution of alanine-390 by valine in the catalytic domain.

Factor IX Niigata is a mutant factor IX responsible for the moderately severe hemophilia B in a patient who has a normal level of factor IX antigen with reduced clotting activity (1-4% of normal). We reported previously that the purified mutant protein could be converted to the factor IXa beta form by factor XIa/Ca2+ at a rate similar to that in the case of normal factor IX, but the resulting mutant factor IXa beta could not activate factor X in the presence of factor VIII, Ca2+, and phospholipids (Yoshioka, A. et al. (1986) Thromb. Res. 42, 595-604). In the present study, we analyzed factor IX Niigata at the structural level to elucidate the molecular abnormality responsible for the loss of clotting activity. Amino acid sequence analysis of a peptide obtained on lysyl endopeptidase digestion, coupled with subsequent SP-V8 digestion, demonstrated that the alanine at position 390 was substituted by valine in the catalytic domain of the factor IX Niigata molecule.

Alanine↗
PubMed1988

The effect of metoclopramide on the absorption and pharmacology of chlorpromazine in the rat.

The mechanism of interaction between metoclopramide (MCP) and chlorpromazine (CPZ) has been examined in rats. MCP given intraperitoneally 30 min before orally administered CPZ significantly enhanced the cataleptic and hypothermic effects of CPZ, and also initially increased its plasma and brain concentrations. However, MCP had no effect on the plasma and brain concentrations of CPZ given as an intravenous bolus, indicating that MCP interacts with CPZ during its intestinal absorption. Furthermore, co-administration of MCP (i.p.) with CPZ (p.o.) markedly accelerated gastric emptying compared with CPZ alone, and MCP (i.v.) did not alter the uptake of CPZ by the intestinal membrane. Therefore, it is concluded that MCP causes an increase in the rate of CPZ absorption, by accelerating the gastric emptying.

Animals↗
PubMed1988

Recent gene conversion between genes encoding human red and green visual pigments.

Nucleotide sequences of the human X-linked red and green pigment genes were compared, and the number of silent substitutions per site (KSc) between these genes was analysed in comparison with the corresponding values of primate genes. Taking the retarded mutation rate of X-linked genes into consideration (Miyata et al., 1987), the red and green pigment genes were shown to have undergone gene conversion at around the time of separation of African apes and orangutan. Thus the recent gene conversion and retarded mutation rate in these X-linked genes are probably responsible for the strong sequence similarity between these genes, which is likely to facilitate the occurrence of red-green color blindness in the human population. It was also shown that the red pigment gene evolved about five times more rapidly than the green pigment gene since the latest gene conversion.

Animals↗
PubMed1988

[A method of protection on out-flow of hydroxyapatite].

Attelocollagen obtained by pepsin treatment from calf skin is very poor antigen. Attelocollagen is the most promising implantable biomaterial because of its lower antigenic property and excellent tissue compatibility. The purpose of this study is to examine that attelocollagen suppress an out-flow of hydroxyapatite. The subject were 16 patients with moderate to advanced periodontal disease who visited Meika university hospital. The clinical examination were performed immediately after the surgery, 1, 2, and 4 weeks after postsurgery. The remains of hydroxyapatite were measured by the roentgenograph and an image analyzer system. As a result, the hydroxyapatite in attelocollagen treated group was remained much more than of control group in 4 weeks (p less than 0.01). In clinical finding, wound healing of attelocollagen treated group was accomplished in 4 weeks and it did not prevent the wound healing of periodontal tissue.

Collagen↗