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M Noda

Publications and source records attributed to M Noda.

At least 541 records · Page 30Linked to original sources
PubMed1988

GTP-binding proteins and adenylate cyclase activity in v-Ki-ras transformed NIH/3T3 fibroblast cells.

To identify the role of ras oncogene and p21 in the coupling mechanism of GTP-binding proteins to adenylate cyclase, we used v-Ki-ras transformed NIH/3T3 fibroblast cells. In the previous study, we investigated that NaF, cholera toxin and forskolin remarkably enhanced the adenylate cyclase activity in transformed cells compared to normal NIH/3T3 cells. In the present study, adenylate cyclase was more enhanced by GTP gamma S in transformed cells than in normal cells. It was considered that p21 plays enhancing role in coupling of GTP-binding proteins to adenylate cyclase. Further, as measured by the degree of [32P] ADP-ribosylation of GTP-binding proteins by cholera toxin and pertussis toxin respectively, the amount of Gs (46 kDa) was almost equal in both cells, while the amount of Gi (41 kDa) in transformant was about one third of that in normal cells. This difference seems to be reflected in either the biological situations or the quantities of Gi. Our data suggest that v-Ki-ras transformation resulted in the decrease of Gi protein so that the inhibitory regulation on adenylate cyclase relatively becomes low and then stimulatory influence of Gs seems to be enhanced.

Adenosine Diphosphate Ribose↗
PubMed1988

Functional expression of cloned cDNA encoding sodium channel III.

mRNA synthesized by transcription in vitro of the cloned cDNA encoding rat brain sodium channel III directs the formation of a functional sodium channel in Xenopus oocytes. The tissue distribution of the mRNAs encoding sodium channels I, II and III has been studied by blot hybridization analysis with specific probes.

Animals↗
PubMed1988

Stimulation of choleragen enzymatic activities by GTP and two soluble proteins purified from bovine brain.

Choleragen (cholera toxin) activates adenylate cyclase by catalyzing ADP-ribosylation of Gs alpha, the stimulatory guanine nucleotide-binding protein. It was recently found (Tsai, S.-C., Noda, M., Adamik, R., Moss, J., and Vaughan, M. (1987) Proc. Natl. Acad. Sci. U. S. A. 84, 5139-5142) that a bovine brain membrane protein known as ADP-ribosylation factor or ARF, which enhances ADP-ribosylation of Gs alpha, also increases the GTP-dependent NAD:arginine and NAD:protein ADP-ribosyltransferase, NAD glycohydrolase, and auto-ADP-ribosylation activities of choleragen. We report here the purification and characterization of two soluble proteins from bovine brain that similarly enhance the Gs alpha-dependent and independent ADP-ribose transfer reactions catalyzed by toxin. Like membrane ARF, both soluble factors are 19-kDA proteins dependent on GTP or GTP analogues for activity. Maximal ARF effects were observed at a molar ratio of less than 2:1, ARF/toxin A subunit. Dimyristoyl phosphatidylcholine was necessary for optimal ADP-ribosylation of Gs alpha but inhibited auto-ADP-ribosylation of the choleragen A1 subunit and NAD:agmatine ADP-ribosyltransferase activity. It appears that the soluble factors directly activate choleragen in a GTP-dependent fashion. The relationships of the ARF proteins to the ras oncogene products and to the family of guanine nucleotide-binding regulatory proteins that includes Gs alpha remains to be determined.

ADP Ribose Transferases↗
PubMed1988

Diversity of the osteoblastic phenotype.

Studies of bone cells in culture have raised two salient questions: are the findings representative of the in vivo situation and can the conflicting data from different cell models be reconciled? Review of the literature indicates that all osteoblastic cells, defined by their origin or by their ability to produce mineralized matrix, have a few common properties: production of type I collagen; increased alkaline phosphatase activity; and parathyroid hormone-stimulated adenylate cyclase. Other features, such as osteocalcin and prostaglandin E production and the response to prostaglandin E, are selectively expressed by certain cell types. Pilot studies on mRNA levels of 'bone proteins' in developing calvaria suggest that such differences may reflect stages in osteoblastic differentiation. Immortalization of calvaria-derived cells using a SV40 large T antigen vector, which may freeze the cells in their particular state of differentiation (as proposed for leukaemia cells), yields phenotypes consistent with that hypothesis. Immortal cell lines may thus help to characterize osteoblastic differentiation. The diversity of osteoblast responses in culture to hormones and growth factors could be due to these phenotype differences but could also represent a subspecialization of differentiated cells. In addition, in the organism regulatory agents act in concert on a heterogeneous interactive cell population. Nonetheless cell cultures can be useful in screening for and predicting in vivo responses, as was shown by the 1,25-(OH)2D3 stimulation of osteocalcin, and for studying the molecular mechanisms of regulatory effects. Cell lines are also convenient for the production of specific proteins and cDNA libraries, and for the expression of specific genes.

Animals↗
PubMed1988

Genome types of adenovirus types 19 and 37 isolated from patients with conjunctivitis in Hiroshima City.

A total of 74 strains out of 33 strains of adenovirus type 19 (Ad19) plus 103 strains of type 37 (Ad37) isolated from patients with conjunctivitis at two ophthalmology clinics in Hiroshima City during the period March 1983 to December 1986 were analyzed by eight DNA restriction endonucleases in comparison with their prototype strains. All 27 Ad19 isolates examined displayed identical DNA cleavage patterns with all enzymes used (HindIII, KpnI, PstI, XhoI, BamHI, SacI, EcoRI, and SmaI), but their cleavage patterns were different from those of the prototype except with HindIII. The genome type of these isolates was tentatively named Ad19a. Forty-seven Ad37 isolates examined were divided into three genome types. They were tentatively named Ad37p, Ad37a, and Ad37b: 16 isolates (Ad37p) displayed DNA cleavage patterns identical with those of the prototype with all eight enzymes described above. Thirty isolates (Ad37a) showed the same patterns as the prototype except with EcoRI. One isolate (Ad37b) showed the same patterns as the prototype except with SmaI. The most frequently isolated genome type during the period studied was Ad37a, but the change of the predominant genome type in yearly incidences was observed.

Adenoviridae Infections↗
PubMed1988

Physicochemical properties of transmissible gastroenteritis virus hemagglutinin.

Transmissible gastroenteritis virus was readily adsorbed onto chicken erythrocytes at 4 degrees C. The hemagglutinin thus adsorbed could be eluted from the erythrocytes by incubating in phosphate buffered saline at 37 degrees C. The receptor on chicken erythrocytes for the hemagglutinin was inactivated by neuraminidase and potassium periodate, but not by trypsin, 2-mercaptoethanol and formalin. The hemagglutinin was inactivated by trypsin, papain, pepsin, alpha-amylase, phospholipase C, neuraminidase, formalin, 2-mercaptoethanol, potassium periodate, ethyl ether, chloroform, Tween-80 and beta-propiolactone, but not by sodium deoxycholate and trichlorotrifluoroethane, suggesting that the active component of the hemagglutinin involved glycoproteins. The hemagglutinin was stable at 37 degrees C or lower temperatures but not at 60 degrees C or higher temperatures. The hemagglutinin activity was resistant to ultraviolet irradiation, while the infectivity was very susceptible. The hemagglutinin and the infectivity were readily sedimented by ultracentrifugation at 45,000 x g for 60 minutes. In rate zonal centrifugation of the hemagglutinin preparation on a sucrose density gradient, the hemagglutinin activity showed a sharp peak at 1.19 g/ml coinciding with the peak of infectivity. The activity in the peak fraction seemed to be structurally associated with virus particles.

Chemical Phenomena↗
PubMed1988

Toxicological analysis of thiamylal in biological materials by gas chromatography/mass spectrometry.

A reliable and sensitive method to analyze thiamylal in biological materials was developed, using gas chromatography/mass spectrometry (GC/MS). A quantitative determination was made by use of mass fragmentography with the lower detection limit of 0.01 microgram/g. Thiopental was used as the internal standard. Distribution of the drug in the blood and body tissues of rats was examined. The method was then used to detect thiamylal in tissues from an autopsied patient and concentration of this drug in the body materials was evaluated, from medico-legal aspects.

Adipose Tissue↗
PubMed1988

Structure and expression of rat osteosarcoma (ROS 17/2.8) alkaline phosphatase: product of a single copy gene.

Alkaline phosphatase [ALP; orthophosphoric-monoester phosphohydrolase (alkaline optimum), EC 3.1.3.1] is a ubiquitous enzyme of unknown function expressed at high levels in cells of mineralizing tissues. To study the structure, function, and expression of ALP, a full-length cDNA of rat ALP (2415 bases) was isolated from a ROS 17/2.8 osteosarcoma cell lambda gt10 cDNA library. The predicted amino acid sequence spans 524 residues and includes an N-terminal signal peptide of 17 amino acids, the phosphohydrolase active site, a rather hydrophilic backbone with five potential N-glycosylation sites, and a short hydrophobic C-terminal sequence. ALP negative CHO cells transfected with an expression vector containing the ALP coding sequences express ALP. The rat bone, liver, and kidney ALP shows remarkable 90% homology with the corresponding human enzyme, the most divergent region being the C-terminal hydrophobic domain through which the enzyme may be anchored to the plasma membrane. The rat ALP also shows 50% homology with the human placental and intestinal ALP and 25% homology with the Escherichia coli ALP. The amino acids involved in catalysis show nearly complete homology among all known ALP sequences, suggesting that these enzymes evolved from a common ancestral gene. The rat ALP cDNA pRAP 54, used as a hybridization probe in RNA blot analysis of several tissues that express ALP, revealed the presence of an ALP mRNA of approximately equal to 2500 bases. Furthermore, hybridization patterns derived from Southern blot analysis of rat chromosomal DNA offered molecular evidence that the ALP expressed in ROS 17/2.8 osteosarcoma and various rat tissues, excluding the intestine, is the product of the same single copy gene.

Alkaline Phosphatase↗
PubMed1988

Influence of sex on age at onset of schizophrenia.

The age at onset of schizophrenia was investigated in 2,417 inpatients (1,433 males and 984 females) meeting the DSM-III criteria for schizophrenia. About 80% of the patients became schizophrenic before the age of 30. The mean age at onset of the male patients was slightly earlier than that of the female patients. There was a higher cumulative percentage of the male patients who became affected at each age quinquennium. More men than women became schizophrenic before the age of 30.

Adult↗
PubMed1988

Comparison of postreceptor effects of 1-34 human hypercalcemia factor and 1-34 human parathyroid hormone in rat osteosarcoma cells.

A tumor-derived factor believed to cause hypercalcemia by acting on the parathyroid hormone (PTH) receptor was recently purified, cloned, and found to have NH2-terminal sequence homology with PTH. The 1-34 region of this protein was synthesized, evaluated for its postreceptor effects on the ROS 17/2.8 cell line, and its properties were compared to 1-34 PTH. Both 1-34 human humoral hypercalcemia factor (HCF) and 1-34 PTH stimulated adenylate cyclase with an effective concentration (EC)50 of approximately 1 nM. The extent of stimulation by both peptides was equally enhanced by dexamethasone. They both had a pronounced inhibitory effect on growth in the presence of dexamethasone, with an EC50 of approximately 0.1 nM, reduced alkaline phosphatase (AP) activity by approximately 70% in the absence of dexamethasone and by approximately 80% in the presence of dexamethasone with an EC50 of 0.03 nM, and when present at a concentration of 10 nM, reduced AP mRNA levels (estimated by Northern analysis) by approximately 80% in the presence or absence of dexamethasone. Thus, in addition to similar dose-response curves for adenylate cyclase stimulation, both HCF and PTH produced identical postreceptor effects in ROS 17/2.8 cells. These effects of HCF are probably mediated by the interaction of the tumor-derived factor with the PTH receptor.

Animals↗