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T Muta

Publications and source records attributed to T Muta.

At least 73 records · Page 4Linked to original sources
PubMed1991

cDNA and amino acid sequences of bovine tissue factor.

A cDNA encoding bovine tissue factor has been isolated from a lambda gt11 bovine adrenal cDNA library. The cDNA insert was 1877 base pairs with an open reading frame of 876 base pairs that encoded a presequence of 35 amino acids and a mature tissue factor of 257 amino acids. Bovine tissue factor had three potential N-glycosylation sites, four extracellular cysteine residues, a cytoplasmic cysteine residue, and one tripeptide tryptophan-lysine-serine motif. Identities of the amino acid sequences of the mature forms between the bovine tissue factor and each of human, mouse, and rabbit tissue factors were 70.4%, 57.2%, and 74.1%, respectively.

Adrenal Glands↗
PubMed1991

Limulus factor C. An endotoxin-sensitive serine protease zymogen with a mosaic structure of complement-like, epidermal growth factor-like, and lectin-like domains.

Factor C is an endotoxin-sensitive, intracellular serine protease zymogen which initiates the coagulation cascade system in the limulus hemolymph. We have determined the entire amino acid sequence of factor C using recombinant DNA technique. The zymogen consisted of 994 amino acid residues with a calculated molecular mass of 109,648 Da. Most interestingly, factor C has five repeating units ("Sushi" domain or short consensus repeat) of about 60 amino acid residues each, which have been found in many proteins participating in the mammalian complement system. In addition to a typical serine protease domain in the carboxyl-terminal portion, characteristic segments with an epidermal growth factor-like, a lectin-like, a cysteine-rich, and a proline-rich domain were also found, revealing a unique mosaic protein structure. The serine protease domain was most analogous to human thrombin. Factor C was identified to localize in large granules in the cell, indicating that it is released from the cell by lipopolysaccharide stimulation. Furthermore, we identified a transcript possibly derived by alternative splicing of factor C mRNA, which encodes a protein sharing the amino-terminal portion of factor C. We suggest that factor C, a newly discovered type of serine protease zymogen, is a "coagulation-complement factor" which may play important roles in both hemostasis and host defense mechanisms.

Amino Acid Sequence↗
PubMed1990

Proclotting enzyme from horseshoe crab hemocytes. cDNA cloning, disulfide locations, and subcellular localization.

Proclotting enzyme is an intracellular serine protease zymogen closely associated with an endotoxin-sensitive hemolymph coagulation system in limulus. Its active form, clotting enzyme, catalyzes conversion of coagulogen to insoluble coagulin gel. We present here the cDNA and amino acid sequences, disulfide locations, and subcellular localization of proclotting enzyme. The isolated cDNA for proclotting enzyme consists of 1,501 base pairs. The open reading frame of 1,125 base pairs encodes a sequence comprising 29 amino acid residues of prepro-sequence and 346 residues of the mature protein with a molecular mass of 38,194 Da. Three potential glycosylation sites for N-linked carbohydrate chains were confirmed to be glycosylated. Moreover, the zymogen contains six O-linked carbohydrate chains in the amino-terminal light chain generated after activation. The cleavage site that accompanies activation catalyzed by trypsin-like active factor B, proved to be an Arg-Ile bond. The resulting carboxyl-terminal heavy chain is composed of a typical serine protease domain, with a sequence similar to that of human coagulation factor XIa (34.5%) or factor Xa (34.1%). The light chain has a unique disulfide-knotted domain which shows no significant homology with any other known proteins. Thus, this proclotting enzyme has a mammalian serine protease domain and a structural domain not heretofore identified in coagulation and complement factors. Immunohistochemical studies showed that the proclotting enzyme is localized in large granules of hemocytes.

Amino Acid Sequence↗
PubMed1990

Antimicrobial tachyplesin peptide precursor. cDNA cloning and cellular localization in the horseshoe crab (Tachypleus tridentatus).

The hemocytes of the horseshoe crab have been found to contain a new family of Arthropodous antibiotics, termed the "tachyplesin family." These peptides are composed of 17-18 amino acid residues with a carboxyl-terminal arginine alpha-amide. We report here the entire cDNA sequence coding for the tachyplesin precursors and their distribution in various tissues of the horseshoe crab. Sequence analysis of the cloned cDNAs revealed that the tachyplesin precursors consist of 77 amino acids with 23 residues in a presegment, and that there are two types of mRNAs corresponding to the isopeptides tachyplesins I and II. Both precursors contain a putative signal peptide, a processing peptide sequence and a carboxyl-terminal amidation signal "Gly-Lys-Arg" connected to the mature tachyplesin peptide. Moreover, an unusual acidic amino acid cluster, Asp-Glu-Asp-Glu-Asp-Asp-Asp-Glu-Glu-COOH, is present in the carboxyl-terminal portions of both precursors. These results suggest that the two types of tachyplesin precursors are first synthesized as preproproteins and are then incorporated into the intracellular organelle, accompanied by various processing events. Northern blot analysis on a total RNA from various tissues of the horseshoe crab revealed that the tachyplesin precursors are expressed mainly in hemocytes and cardiac and brain tissues. Tachyplesin was immunohistochemically localized in the smaller dense granules rather than the typical large granules present in abundance in the hemocytes.

Amino Acid Sequence↗
PubMed1990

Cysteine proteinase inhibitor in the ascitic fluid of sarcoma 180 tumor-bearing mice is a low molecular weight kininogen. Partial NH2- and COOH-terminal sequences and susceptibility to various glandular kallikreins.

It has been proposed that a cysteine proteinase inhibitor (CPI) found in the ascitic fluid of Sarcoma 180 tumor-bearing mice is a kind of kininogen (Itoh, N., Yokota, S., Takagishi, U., Hatta, A., and Okamaoto, H. (1987) Cancer Res. 47, 5560-5565). The first 40 NH2-terminal residues and 54 residues of the COOH-terminal sequence, including the bradykinin moiety of highly purified ascites CPI, were determined and compared with those of mammalian low molecular weight kininogens (LMWK). The significant identity between these amino acid sequences with those of other mammalian LMWKs suggests that ascites CPI corresponds precisely to mouse LMWK. This kininogen has a light chain composed of 43 amino acid residues, which contains a unique Met-Ala-Arg-bradykinin sequence. Hydroxyproline, which was recently identified in the bradykinin sequence of kininogen from the ascitic fluid of a cancer patient, was not found in the kinin moiety of this mouse kininogen. Among purified glandular kallikreins from human, hog, rat, and mouse, only mouse submaxillary gland kallikrein was able to release bradykinin from this kininogen. Kinetic studies using a newly synthesized fluorogenic substrate, N-t-butoxycarbonyl-Met-Ala-Arg-MCA, revealed that mouse kallikrein hydrolyzes this substrate approximately 80-fold faster than does hog kallikrein, suggesting that the unique Met-Ala-Arg-bradykinin sequence is responsible for the varied susceptibility of mouse kininogen to different kallikreins.

Amino Acid Sequence↗
PubMed1990

Tachyplesins isolated from hemocytes of Southeast Asian horseshoe crabs (Carcinoscorpius rotundicauda and Tachypleus gigas): identification of a new tachyplesin, tachyplesin III, and a processing intermediate of its precursor.

Tachyplesins and their analogs are antimicrobial peptides composed of 17 or 18 amino acid residues present abundantly in acid extracts of hemocyte debris of horseshoe crabs. We purified here tachyplesin isopeptides from hemocytes of two species of Southeast Asian horseshoe crabs, Carcinoscorpius rotundicauda and Tachypleus gigas, and determined their amino acid sequences. The major tachyplesin isolated from both species was identified, respectively, as tachyplesin I, which had previously been found in hemocytes of the Japanese horseshoe crab (Tachypleus tridentatus). The yield from both species was very high (more than 70 mg per 100 g wet weight of hemocytes), i.e., comparable with that from T. tridentatus. In addition to tachyplesin I, a new tachyplesin isopeptide, named tachyplesin III, was also isolated from T. gigas hemocytes, in which an arginine replaced the 15th lysine of tachyplesin I. The carboxyl-terminal residue of the isolated tachyplesins I and III was confirmed, respectively, to be an arginine alpha-amide by chemical analysis. Furthermore, a tachyplesin peptide derivative with a carboxyl-terminal extension of glycine-lysine was newly found in the hemocytes of C. rotundicauda. It appeared to be an intermediate derived from a tachyplesin precursor during processing to the mature form.

Amino Acid Sequence↗
PubMed1988

[Effects of analogues and drugs on arginine vasopressin receptor binding in rat renal tubular basolateral membrane].

The methods of basolateral membrane isolation from rat kidney and 3H-AVP receptor assay using this basolateral membrane preparation were established. Then, the effects of analogues and drugs on AVP-receptor binding were studied. Specific 3H-AVP binding was inhibited by LVP, dDAVP and oxytocin in that order. Among the various agonistic or antagonistic drugs to AVP (fluoride, cyclophosphamide, mechlorethamine, chlorpropamide), only chlorpropamide inhibited 3H-AVP binding to the membrane. The Kd value calculated by Scatchard analysis was 1.30 +/- 0.28 nM (n = 4, M +/- SD), and it was increased to 2.69 +/- 0.32 nM (n = 5, M +/- SD) by adding 1 mM of chlorpropamide, while Bmax was unchanged. Our data show that 1 mM chlorpropamide decreases receptor affinity for AVP, and alters AVP-receptor binding in a competitive manner.

Animals↗
PubMed1988

Tachyplesin, a class of antimicrobial peptide from the hemocytes of the horseshoe crab (Tachypleus tridentatus). Isolation and chemical structure.

A cationic peptide, designated tachyplesin, was isolated from acid extracts of horseshoe crab (Tachypleus tridentatus) hemocyte debris. It consists of 17 residues and the structure determined by Edman degradation is: (formula; see text) The carboxyl-terminal end of this peptide was identified as arginine alpha-amide, and the whole sequence including the alpha-amide was also confirmed by fast atom bombardment mass spectrometry, indicating a mass value of 2263. Tachyplesin inhibits growth of both Gram-negative and -positive bacteria at low concentrations and formed a complex with bacterial lipopolysaccharide. Tachyplesin seems likely to act as antimicrobial peptide for self-defense in the horseshoe crab against invading microorganisms.

Amino Acid Sequence↗
PubMed1988

Chromosomes and surface markers in lymph node cells from 2 patients with AILD and IBL-like T-cell lymphoma.

Chromosomes and surface markers in lymph node cells from 2 patients with angioimmunoblastic lymphadenopathy associated with dysproteinemia (AILD) or immunoblastic lymphadenopathy (IBL) and with IBL-like T-cell lymphoma, respectively, were examined before treatment. In the patient with AILD, a small clone with chromosome abnormality was found in lymph node cells although a surface marker study failed to demonstrate monoclonality. In this patient, the clinical and cytogenetic findings suggested a subtype of lymphoma with a mild clinical course and a benign histological appearance. In the patient with IBL-like T-cell lymphoma, a high percentage of metaphases showed chromosome abnormalities such as ring chromosomes. The clinical, immunological and cytogenetic findings suggested an aggressive type of lymphoma, even though the histologic appearance was similar to that of IBL.

Adult↗
PubMed1987

Primary structure of anti-lipopolysaccharide factor from American horseshoe crab, Limulus polyphemus.

The complete amino acid sequence of anti-lipopolysaccharide (LPS) factor purified from the hemocytes lysate of the American horseshoe crab, Limulus polyphemus, was determined by characterization of the NH2-terminal sequence and the peptides generated after digestion of the protein with lysyl endopeptidase, clostripain, and Staphylococcus aureus V8 protease. Upon sequencing the peptides by the automated Edman method, the following primary structure was obtained: (Sequence: in text). During the sequence analysis, two species of the protein, which differed from each other at one locus, were found and characterized. L. polyphemus anti-LPS factor was a basic protein consisting of a single polypeptide chain of 101 residues and a calculated molecular weight of 11,786 or 11,800. The hydrophobic NH2-terminal sequence and the clustering of positive charges found in the disulfide loop yielded a typical amphipathic character of this protein. Moreover, L. polyphemus anti-LPS factor showed 83% sequence identity with the Tachypleus tridentatus protein, and the sequence similar to that observed in the EF-hand structure was found to contain in the COOH terminal portions of these proteins, although its function is unknown.

Amino Acid Sequence↗
PubMed1985

Molecular and functional organization of yeast plasmid pSR1.

The nucleotide sequence of a 6251 base-pair plasmid, pSR1, harbored in an osmophilic haploid yeast, Zygosaccharomyces rouxii (formerly Saccharomyces rouxii), was determined. No homology was detected between the sequences of pSR1 and 2-micron DNA of Saccharomyces cerevisiae. pSR1 has a pair of inverted repeats consisting of completely homologous 959 base-pair sequences, which separate two unique sequences 2654 base-pairs and 1679 base-pairs long. Each inverted repeat has an ARS sequence functional in both Z. rouxii and S. cerevisiae hosts. Short direct repeats or dyad symmetries were observed in the inverted repeats similar to those found close to the replication origin of 2-micron DNA. Three open reading frames, P, S and R, each able to encode a protein of molecular weight larger than 10,000, were found. Insertional inactivation of R gave rise to a defect in the intramolecular recombination at the inverted repeats, and that of S reduced the copy number of pSR1 in the S. cerevisiae host. The maintenance stability of the plasmid was also tested in the heterogeneous S. cerevisiae host, but the results of the insertional inactivation of P, S and R were ambiguous. pSR1 and 2-micron DNA were compatible in S. cerevisiae cells, but the protein factors encoded by these plasmids did not complement each other.

Base Sequence↗
PubMed1982

Clinical, hematologic, and pathologic features of leukemic T-cell lymphoma.

Cells obtained from malignant lymph nodes and the peripheral blood of 106 patients with non-Hodgkin's lymphomas were examined for T- and B-cell characteristics. Surprisingly, 79 cases were of the T-cell type on the basis of spontaneous rosette formation with sheep erythrocytes (E-rosettes). Of the remaining cases, 15 were B-cell in nature (monoclonal S-Ig positive), seven were non T-, non B-cell and four cases were undetermined. Forty-nine (62.0%) of the T-cell malignancies were of a leukemic variety, characterized by pleomorphism in the peripheral blood cell size, and histological appearance. Most of the leukemic T-cells showed obvious lymphocytic differentiation, with condensed nuclear chromatin and scant cytoplasm, although in many of the cases, the lymphomatous infiltrate was dominated by large or pleomorphic lymphoid cells. All tumors were of a diffuse variety, and on histologic examination included a mixed type (21 cases), PDLL forms (15 cases), a large lymphoid cell type (eight cases), and WDLL forms (five cases). Although the mixed type with a pleomorphic lymphoid infiltrate was distinctive, there has been considerable variation from case to case. Clinically this unusual t-cell, leukemic variety of non-Hodgkin's lymphomas primarily involved middle-aged and elderly subjects, and was characterized by wide spread organ invasion (preferentially to the liver, spleen and skin), resistance to chemotherapy, and a poor prognosis. A mediastinal mass was not observed in all cases. The patients had a median survival of only ten months.

Adolescent↗