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Biomedical subjects

M Noda

Publications and source records attributed to M Noda.

At least 307 records · Page 17Linked to original sources
PubMed1996

MCC, a cytoplasmic protein that blocks cell cycle progression from the G0/G1 to S phase.

The MCC gene was isolated from the human chromosome 5q21 by positional cloning and was found to be mutated in several colorectal tumors. In this study, we prepared specific antibodies and detected the MCC gene product as a cytoplasmic 100-kDa phosphoprotein in mouse NIH3T3 cells. Immunoelectron microscopic analysis showed that the MCC protein is associated with the plasma membrane and membrane organelles in mouse intestinal epithelial cells and neuronal cells. The amount of the MCC protein remained constant during the cell cycle progression of NIH3T3 cells, while its phosphorylation state changed markedly in a cell cycle-dependent manner, being weakly phosphorylated in the G0/G1 and highly phosphorylated during the G1 to S transition. Overexpression of the MCC protein blocked the serum-induced cell cycle transition from the G1 to S phase, whereas a mutant MCC, initially identified in a colorectal tumor, did not exhibit this activity. These results suggest that the MCC protein may play a role in the signaling pathway negatively regulating cell cycle progression.

3T3 Cells↗
PubMed1996

A membrane-bound heparan sulfate proteoglycan that is transiently expressed on growing axons in the rat brain.

Monoclonal antibodies were raised to membrane-bound proteoglycans derived from rat brain and three monoclonal antibodies that recognized a 200-kDa heparan sulfate proteoglycan (designated H5-PG) with a core glycoprotein of 140 kDa were obtained. The expression of H5-PG was spatially and temporally regulated in the central nervous system. In the cerebellar cortex, H5-PG was associated mainly with the actively growing parallel fibers of granule cells. The expression was abruptly down-regulated in parallel with the formation of synapses on dendrites of Purkinje cells. In the cerebral cortex, the proteoglycan was widely distributed throughout the cortex. The temporal pattern of expression was similar to that in the cerebellar cortex; the peak level of expression was observed during the period from postnatal days 0 to 20 when neuritogenesis and synaptogenesis occur most extensively in the rat cerebral cortex. H5-PG in the central nervous system disappeared prior to adulthood except in the olfactory bulb. High-level expression was recognized on the olfactory nerves and glomeruli, where the renewal of both axons and synapses is occurring constantly. The data suggest that H5-PG is a glycoconjugate on axonal surface that is involved in axonal outgrowth and/or synaptogenesis.

Animals↗
PubMed1996

Streptozotocin, an inducer of NAD+ decrease, attenuates M-potassium current inhibition by ATP, bradykinin, angiotensin II, endothelin 1 and acetylcholine in NG108-15 cells.

The M-potassium current was inhibited by bath application of 100 micron ATP, 10 nM bradykinin, 100 nM angiotensin II and 100 nM endothelin 1 as well as by 10 micron acetylcholine in an m1-muscarinic acetylcholine receptor-transformed NG108-15 cell line. The inhibition of M-current was attenuated in cells pretreated with 5 mM streptozotocin for 5-15 h and restored by simultaneous incubation with 5 mM nicotinamide. The results suggest that signal transduction from these five different receptors to M channels shares a common pathway which is susceptible to a streptozotocin-induced decrease in cellular NAD+ content.

Acetylcholine↗
PubMed1996

Transactivation activity of Maf nuclear oncoprotein is modulated by Jun, Fos and small Maf proteins.

The v-maf oncogene encodes a nuclear bZip protein which specifically recognizes relatively long palindromic sequences related to an AP-1 site. In this study, we investigated the relationship of transactivation and transformation activity of Maf. The amino-terminal two thirds of the molecule were dispensable for its DNA-binding activity but conferred its transactivation potential. Transactivation activities of a set of deletion mutants correlated well with their cell transforming abilities. However, a point mutant associated with enhanced oncogenic activity was not more effective in transactivation than the wild type, suggesting that some other function(s) of Maf is also important for its transforming ability. We also examined the effect of other bZip proteins on the transactivation activity of Maf. Three small Maf family proteins (MafK, MafF and MafG), which are missing the transactivation domain of v-Maf, competitively inhibited transactivation by Maf. Co-expression of Jun or Fos also affected the transactivation potential of Maf by forming Maf/Jun or Maf/Fos heterodimers of distinct DNA-binding specificities. In addition to these factors, we noticed the presence of a strong endogenous transactivating activity associated with a sequence related to an NF-E2 site rather than the typical AP-1 site in fibroblast cells. These results indicate that AP-1 site-like cis-regulatory elements of eukaryotic genes are regulated by multiple sets of bZip dimers with different DNA-binding and transactivation properties.

3T3 Cells↗
PubMed1996

Plasma cells composing plasmacytoma have phenotypes different from those of myeloma cells.

We describe one relapsed case of plasmacytoma of mandibular bone. The organs of relapse were liver and bone marrow. At relapse, monoclonal gammopathy (IgG-kappa) was observed without suppression of IgA and IgM. By immunostaining, the plasma cells of both the original mandibular bone and liver were positive for the same cytoplasmic immunoglobulin light chain kappa. The proliferative plasma cells in the bone marrow had the phenotype of CD38+, CD19+, and CD56- by flow cytometry and showed the presence of the rearranged IgH gene by Southern blotting. In addition, the zone of the Ig class of the patient's serum was not so sharply defined by zone electrophoresis. These results suggest that the characteristics of plasma cells of plasmacytoma are different from those of multiple myeloma.

ADP-ribosyl Cyclase↗
PubMed1996

Establishment of a novel chondrocyte-like cell line derived from transgenic mice harboring the temperature-sensitive simian virus 40 large T-antigen gene.

We established a clonal chondrocyte-like cell line (TC6, TC stands for large T immortalized chondrocyte-like cell line) derived from articular cartilage of transgenic mice harboring a temperature-sensitive simian virus 40 large T-antigen gene. TC6 cells exhibited spindle-like or polygonal morphology and grew well at 33 degrees C in alpha-minimal essential medium supplemented with 0.5% fetal bovine serum. After confluence, these cells formed nodules that were positive for staining with alcian blue. Northern blot analysis demonstrated that these cells expressed messenger RNAs (mRNA) of the genes encoding cartilage-specific proteins such as type II procollagen, link protein, and aggrecan. Furthermore, the expression of type II procollagen and link protein genes in TC6 cells was regulated by parathyroid hormone and basic fibroblast growth factor, suggesting the presence of the receptors for the hormone and cytokine. The expression of link protein mRNA in TC6 cells was regulated in a time-dependent manner and was enhanced in culture within a week and increased continuously up to 10-fold by the end of 4 weeks. Expression of mRNAs encoding type II procollagen and versican/PG-M also increased moderately during the culture period. TC6 cells expressed type I procollagen mRNA, however, its level declined along with time in culture in contrast to the enhancement of the genes encoding cartilage-specific molecules in these cells. Interestingly, alkaline phosphatase mRNA expression was barely detectable in the TC6 cells in their growing phase while it was enhanced dramatically more than 7-fold by day 14 in culture. These results indicate that the TC6 cells could serve as an excellent model for the studies on chondrocyte physiology.

Animals↗
PubMed1996

Cell surface-associated extracellular distribution of a neural proteoglycan, 6B4 proteoglycan/phosphacan, in the olfactory epithelium, olfactory nerve, and cells migrating along the olfactory nerve in chick embryos.

The immunocytochemical and immuno-electron microscopic distribution of a neural proteoglycan (PG) was investigated with a monoclonal antibody, MAb 6B4, in the olfactory epithelium, the olfactory nerve, and the cells originating the epithelium and migrating along the olfactory nerve toward the forebrain in chick embryos. The PG recognized by MAb 6B4, that is 6B4 PG, in the brain of early postnatal rats, is identical to phosphacan. In chick embryos, immunoreactivity to 6B4 PG appeared on embryonic day (ED) 3-3.5 in a thin layer beneath the olfactory epithelium. It disappeared immediately, then becoming apparent in the bundles of the olfactory nerve. The immunoreactivity in the nerve bundles gradually increased during ED 5-11. On the other hand, cell surface-associated extracellular localization of the immunoreactivity was seen in the olfactory epithelium on ED 6 and afterwards. Immunofluorescent double-labeling of 6B4 PG and gonadotropin-releasing hormone (GnRH) revealed that the cell bodies of both GnRH-containing cells and other cells migrating along the olfactory nerve were surrounded by a rim immunoreactive to the PG. Under an electron microscope, the surfaces of the cell bodies and of the neurites in the nerve bundles were surrounded by deposits immunoreactive to 6B4 PG. These results indicate that 6B4 PG in chick embryos is one type of cell surface-associated extracellular matrix molecule, and that 6B4 PG covered the surfaces of migrating cells and of elongating olfactory nerve. The cell surface-associated extracellular localization of 6B4 PG found in the nasal region, taken together with the binding properties of this PG with cell adhesion molecules shown in rat brains, suggested that 6B4 PG played a role in guiding the migration of cells along the olfactory nerve in chick embryos.

Animals↗
PubMed1996

Expression and functional characterization of the P-selectin glycoprotein ligand-1 in various cells.

We have examined the expression and function of P-selectin glycoprotein ligand-1 (PSGL-1), which is a high affinity ligand for P-selectin. Northern blot and flow cytometric analysis demonstrated that a variety of hematopoietic cells and cell lines expressed PSGL-1. However, P-selectin binding ability was dependent on the additional expression of a carbohydrate structure, sialyl Lewis x (sLex). All the peripheral lymphocytes expressed PSGL-1 and subpopulation expressed sLex. Two color analysis showed that the majority of the cells that bound P-selectin were sLex-negative I lymphocytes, and most of the sLex-positive cells were B lymphocytes that did not blind P-selectin, indicating that the carbohydrate on T lymphocytes recognized by P-selectin is not sLex, and that the sLex on B lymphocytes is not readily presented for P-selectin recognition. Transfected 293 cells detectably bound P-selectin only when the cells expressed both PSGL-1 and sLex. When cysteine 310 of PSGL-1 was mutated to alanine, P-selectin binding was markedly reduced, suggesting the importance of dimerization of PSGL-1. These findings indicate that a preferable conformation of both carbohydrate and protein structure is necessary for a functional P-selectin ligand.

B-Lymphocytes↗
PubMed1996

Inositol trisphosphate/Ca2+ as messengers of bradykinin B2 and muscarinic acetylcholine m1-m4 receptors in neuroblastoma-derived hybrid cells.

Neuroblastoma x glioma hybrid NG 108-15 and neuroblastoma x fibroblast hybrid NL308 cells possess endogenous bradykinin B2 receptors and m4 muscarinic acetylcholine receptors (mAChRs), which couple to phospholipase C and adenylate cyclase, respectively. Four genetic subtypes of mAChRs differed in their effects when stimulated in NG108-15 and NL308 cells overexpressing mAChRs. Broadly speaking, the principal effects fell into two categories: the odd-numbered receptors (m1 and m3) activated phospholipase C and increased inositol trisphosphate/Ca2+, as bradykinin did, whereas the even-numbered receptors (m2 and m4) inhibited adenylate cyclase via a pertussis toxin (PTx)-sensitive G-protein in NG108-15 cells. But all four types of NL308 cells overexpressing each m1, m2, m3 and m4 receptor activated phospholipase C, while keeping the PTx-sensitivity in m2/m4, but not in m1/m3 receptors. Coupling to ion channel effectors showed a comparable dichotomy in NG108-15 cells, while cross-activation occurred in NL308 cells.

Animals↗
PubMed1996

Design and synthesis of C-linked fucosides as inhibitors of E-selectin.

Two series of C-linked fucosides as mimetics for the tetrasaccharide sialyl Lewis X have been synthesized and tested as inhibitors of E-Selectin. The fucopeptides have been prepared from three key intermediates, including alpha-C-allyl fucose, natural and unnatural amino acids bearing hydroxyl groups and an alpha, omega-diacid moiety for the imitation of the essential three parts of SLex, i.e., the Fuc, Gal, and NeuAc. The nature and distance of the linkage of the fucose moiety to the amino acids as well as the distance between the amino acids and the terminal carboxylic acid group turned out to be crucial for the biological activity. In addition the necessity of both OH groups (4- and 6-OH) in the Gal part could be confirmed. Conformational NMR study of the most active mimetic supports the structure-activity relationship. A second series of mimetics was prepared, where Fuc and Gal moieties were purely C-linked. In the synthesis of beta-C-allyl galactose an intramolecular 1,2-hydride shift led to an interesting side product. However, the substituted glycosidic oxygens led to a substantial loss of conformational constrain, which could not be compensated and resulted in low activity.

E-Selectin↗
PubMed1996

Angiographic findings of Takayasu arteritis: new classification.

Having proposed a new classification on angiographic findings of patients with Takayasu arteritis, we evaluated the angiographic findings of 80 Japanese patients and 102 Indian patients according to this classification. Japanese patients showed a higher frequency of involvement of the ascending aorta, aortic arch and its branches than did the Indians (P < 0.01). On the other hand, the frequency of involvement of the abdominal aorta and/or renal arteries was higher in Indian patients (P < 0.01). Type III cases of the new classification which involves the thoracic descending aorta, abdominal aorta and/or renal arteries were observed in 3% of the Indian patients, but not at all in the Japanese. In conclusion, in Japanese patients, vascular lesions tend to occur primarily in the ascending aorta, aortic arch and/or its branches and extend into the abdominal aorta. On the other hand, in Indian patients, the tendency is primarily in the abdominal aorta including renal arteries and extending into the thoracic aorta.

Adolescent↗
PubMed1996

Phosphorylation of a 25 kDa protein is induced by thermostable direct hemolysin of Vibrio parahaemolyticus.

Thermostable direct hemolysin (TDH) is a possible virulence factor produced by Vibrio parahaemolyticus. Although TDH has a variety of biological activities, including hemolytic activity, the biochemical mechanism of action remains uncertain. Here we analysed biochemical events, especially phosphorylation, caused by TDH in erythrocytes, and found that TDH caused significant phosphorylations of proteins on erythrocyte membrane. Phosphorylation of proteins was studies using [gamma-32P] ATP and SDS-PAGE. A number of protein kinase inhibitors were tested, to determine which types of kinases were involved in the phosphorylation events. TDH induced the phosphorylation of two proteins on membranes of human erythrocyte that are sensitive to TDH. The estimated molecular weight of these proteins was 25 and 22.5 kDa. Interestingly, the 22.5 kDa, but not the 25 kDa protein, was phosphorylated on the membrane of TDH-insensitive (resistant) horse erythrocytes. Moreover, a mutant TDH (R7), which retained binding ability but lost hemolytic activity, also phosphorylated only the 22.5 kDa protein on human erythrocyte membranes. Among the protein kinase inhibitors used the protein kinase C inhibitors, (staurosporine and calphostin C) showed marked inhibition of phosphorylation of 25kDa protein. In addition to phosphorylation, these protein kinase C inhibitors suppressed hemolysis by TDH. These results indicate that the phosphorylation of the 25 kDa protein seems to be essential for the hemolysis by TDH after it binds to erythrocyte membranes.

Bacterial Toxins↗
PubMed1996

Oligoclonal accumulation of T cells in peripheral blood from patients with idiopathic thrombocytopenic purpura.

To determine whether clonal T cells accumulate in idiopathic thrombocytopenic purpura (ITP), we performed single-strand conformation polymorphism (SSCP) analysis to detect T-cell receptor (TCR) beta-chain usage of peripheral T cells. We detected significantly more oligoclonal T cells (15.5 +/- 8.9 bands representative for clonal T-cell expansions) in peripheral blood from ITP patients than from healthy donors (2.8 +/- 2.6 bands). Frequently used V beta genes in these accumulated T cells in ITP were V beta 3, 6, 10, 13.1 and 14. To determine whether these bands were derived from clonal T cells, presumably in a preactivated state, we established some T-cell clones (expressing CD4 and TCR V beta 6. 13.1. or 14) by nonspecific stimulation from patients peripheral mononuclear cells, and examined their clonotypes. Clonal identities for three out of seven clones tested were confirmed using SSCP analyses to compare the migration of their beta-chain complementarity determining region 3 (CDR3) cDNAs, expanded by polymerase chain reaction (PCR) with those from peripheral blood. Therefore, distinctive T-cell clones accumulated in the periphery in ITP and they may be related to the autoimmune-mediated destruction of platelets.

Adult↗
PubMed1996

Long-term alcohol intake enhances ADP-ribosylation of the multifunctional enzyme, phosphoglucomutase, in rat liver.

Adenosine diphosphate (ADP)-ribosylation is a posttranslational protein modification that, in turn, alters several regulatory proteins in mammalian cells. We demonstrated that long-term alcohol intake enhanced the ADP-ribosylation of a 58-kd protein in rat liver plasma membranes. To assess the biological significance of this phenomenon, we partially purified the 58-kd acceptor protein from solubilized rat liver homogenates by two sequential preparative high-pressure liquid chromatographies. Microsequencing revealed that it was phosphoglucomutase (PGM) (EC 5,4,2,2). This enzyme underwent negligible auto ADP-ribosylation, but the ADP-ribosylation was remarkably increased by adding rat liver plasma membranes. The extent of the increase was greater in alcohol-fed rats than in pair-fed controls, suggesting enhanced enzyme activities toward ADP-ribosylation of PGM after chronic alcohol consumption. Several important enzymes are ADP-ribosylated, after which their activities are modified. The results of this study showed that PGM is a novel substrate for ADP-ribosylation in the liver and that the ADP-ribosylation is increased after chronic alcohol consumption. In view of the variety of roles of PGM in the liver (carbohydrate metabolism and Ca2+ homeostasis), specific roles of this modification in terms of the effects of alcohol on hepatocytes may deserve further investigation.

Adenosine Diphosphate Ribose↗
PubMed1996

BMP-4 mediates interacting signals between the neural tube and skin along the dorsal midline.

BACKGROUND: The neural tube and its overlying tissues (skin and mesenchyme) interact along the dorsal midline during early development. This has been previously demonstrated experimentally in chicken embryos by the fact that the dorsal neural tube transplanted ectopically induced expression of Msx 2 in the adjacent tissues. It is important to identify the molecules responsible for these interactions. RESULTS: We observed that BMP-4, a member of the TGFbeta-family, is expressed in the dorsal neural tube in a pattern closely correlated with that of Msx 2. In order to investigate whether BMP-4 mediates the signal between the neural tube and the skin/mesenchyme, BMP-4 was ectopically administered in ovo either by implantation of the recombinant protein or transplantation of COS cells producing BMP-4. Both manipulations resulted in ectopic induction of Msx 2 expression in the adjacent skin/mesenchyme. In addition, the activity of BMP-4 in inducing Msx 2 was counteracted by the floor plate. CONCLUSION: These data suggest that BMP-4 positively mediates the signals from the neural tube to the adjacent tissues and that this signal may be an essential step for the establishment of the dorsal midline structures.

Bone Morphogenetic Protein 4↗
PubMed1996

Effects of long-term alcohol intake on ADP ribosylation in rat liver plasma membranes.

Mono-ADP-ribosylation, In which the ADP-ribosyl moiety is transferred from NAD to an acceptor protein, is one of the important posttranslational modifications of cellular proteins. Because mounting evidence suggests significant biological roles of this reaction in transmembrane signal transduction and other cell metabolic reactions, we assessed how long-term alcohol intake alters toxin catalyzed- and endogenous mono-ADP-ribosylation in the liver of a rat model. We first found that thiol-preactivated cholera toxin-catalyzed ADP-ribosylation of the alpha-subunit of the stimulatory GTP-binding protein was enhanced after long-term alcohol intake. Unexpectedly, but interestingly, this enhancement was not accompanied by a concomitant increase of cholera toxin-catalyzed stimulation of the adenylate cyclase activity. We also found that long-term alcohol intake remarkably enhanced endogenous mono-ADP-ribosylation of a 58 kDa protein in plasma membranes. Thus, long-term alcohol intake stimulated endogenous, as well as, toxin-catalyzed mono-ADP-ribosylations. Characterization of the 58 kDa protein may uncover pathophysiological roles of this interesting phenomenon in alcohol-induced liver damage.

ADP Ribose Transferases↗
PubMed1996

[Isolation and analysis of amino acid sequence of V3 region of HIV-1 from patients with HIV-infection in Hiroshima].

Isolation of HIV-1 was tried in PBMCs separated from 27 blood samples which were sent to Hiroshima Prefectural Institute for Health & Environment Science for anti-HIV antibody-test. 18 samples were positive for HIV-isolation (4 samples were Rapid/High type, 12 samples were Slow/Low type and 2 samples were intermediate). Compared with clinical stages of patients, samples from patients in CDC-II were 64% (14/22) positive and those in CDC-IV were 100% (3/ 3) positive in HIV-isolation. Improvement of the methods is to be required to isolate HIV from the samples of patient in the latent phase. Removal of CD8 positive cells from PBMCs of patients did not affect the efficiency of HIV-isolation by our methods. Three parts in amino acid sequence of V3 region in proviruses were different between Rapid/High type isolated and Slow/Low type isolates. The difference of amino acid may be related to the different phenotypes of the two viruses.

Amino Acid Sequence↗