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1.
M Asano  M Nishizawa  S Nagata 《Gene》1991,107(2):241-246
At least three regulatory elements GPE1, GPE2 and GPE3 (G-CSF promoter elements) controlling the gene (G-CSF) encoding granulocyte colony-stimulating factor (G-CSF) are indispensable for the constitutive expression of the G-CSF gene in human CHU-2 cells and for its lipopolysaccharide(LPS)-inducible expression in macrophages. The enhancer activities of each regulatory element were examined with or without the SV40 enhancer element placed downstream from the reporter gene. A GPE1 tetramer mediated the constitutive expression in CHU-2 cells, and the LPS-inducible expression in macrophage cell lines, while the GPE2 element was active in CHU-2 and LPS-treated macrophage cell lines only in combination with the SV40 enhancer. A GPE3 tetramer had efficient enhancer activity in CHU-2 cells but not in macrophage cell lines without the SV40 enhancer. In combination with the SV40 enhancer, GPE3 worked as an LPS-inducible enhancer element in macrophage BAM3 cells. Gel retardation assay indicated that the CHU-2 and the macrophage cells contained nuclear factors which specifically bound to each GPE sequence.  相似文献   
2.
A method for determination of the redox level of plastoquinoneA in spinach chloroplasts is described. Plastoquinone A andits reduced form plastoquinol A were extracted from chloroplastson a sample-preparation cartridge (SEP-PAK C18 Cartridge, WatersAssoc. Inc.) with a mixture of ethanol and diethyl ether ( 1: 1, vv). Extracts were separated by reversed-phase high-performanceliquid chromatography and examined with an electrochemical detectorequipped with dual electrodes. Plastoquinone A was determinedby its reductive current on one electrode, and plastoquinolA by its oxidative current on the other electrode. This method was applied to the determination of the redox potentialof plastoquinone A in chloroplasts. The midpoint potential atpH 7.8 of plastoquinone A was +20 mV with an n number of 2. (Received March 30, 1987; Accepted August 3, 1987)  相似文献   
3.
It is known that the antibody to human myelin-associated glycoprotein (MAG) reacts with a subset of human mononuclear cells (MNC) mediating a natural killer (NK) activity. The properties of the target molecule of the anti-MAG antibody, however, have not yet been elucidated. Three (GC-J4, MC-P2, and MC-P4) of five murine monoclonal antibodies (mAb) to MAG bound to human MNC. Moreover, MC-P2 and MC-P4 inhibited the binding of 125I-labeled anti-Leu-7 to MNC in a dose-dependent fashion. Conversely, anti-Leu-7 inhibited the binding of MC-P2 and MC-P4 to MNC, but did not inhibit the binding of GC-J4. Therefore, it is possible that MC-P2 and MC-P4 bind directly to or close to the Leu-7 epitope, and that GC-J4 binds to the epitope which is distinct from the Leu-7 epitope. The electrophoretic patterns of immunoprecipitates with GC-J4, MC-P2 and anti-Leu-7 from detergent lysates of surface-labeled human MNC were very similar. The target molecules of anti-Leu-7 and anti-MAG mAb have apparent m.w. of 205, 170, 150, 135, 110, 85, 65, and 55 kDa. All of the molecules precipitated by these mAb are monomeric or noncovalently associated proteins, because the electrophoretic mobilities of the proteins remained unchanged whether the samples were reduced or not. MC-P4 may have a higher affinity for the 65 kDa molecule than the other mAb, and precipitates the 58 kDa molecule as well. Therefore, the fine antigenic specificity of MC-P4 is slightly different from those of anti-Leu-7 or MC-P2. The implication of these results is that mAb, whose specificity is directed to the carbohydrate part of human MAG, reacts with the Leu-7 reactive molecules on human MNC, and that at least two epitopes detected by anti-MAG mAb coexist on the surface molecules with various apparent m.w.  相似文献   
4.
5.
The transforming activity of the human fyn protein, p59fyn, which is a kinase of the src family, was investigated by testing the effect of recombinant avian retrovirus (Fyn virus) expressing p59fyn on chickens or cultured chicken embryo fibroblast (CEF) cells. The Fyn virus did not induce transformed foci. After several passages of the virus stock on CEF cells, however, a few foci were detected in the presence of dimethyl sulfoxide. Chickens inoculated with Fyn virus at the stage of 12-day-old embryos developed fibrosarcomas 3 to 6 weeks after hatching. The viruses obtained from these foci and from one of the tumor tissues showed high transforming activity in the presence of dimethyl sulfoxide, suggesting that these viruses carry spontaneous mutations of the fyn gene. Four fyn genes from CEF DNAs infected with transforming viruses were molecularly cloned, and their products were confirmed to possess transforming activity. DNA sequence analysis of the fyn genes showed that two of the four mutants have Thr instead of Ile at position 338 in the kinase domain. The other two mutants carry deletions of 78 and 108 base pairs, respectively, which result in complete loss of region C of SH2. The overall level of proteins containing phosphotyrosine was significantly higher in transformed cells than in normal CEF cells. Our data indicate that when expressed at high levels in a retrovirus, normal p59fyn cannot cause cellular transformation, but that mutant p59fyn with either a single amino acid substitution in the kinase domain or a deletion including region C produces a transforming protein, perhaps due to enhanced tyrosine kinase activity. This is the first observation that deletion of region C can unmask the potential transforming activity of a src family kinase.  相似文献   
6.
Summary This is the first full report on the genetic linkage between Japanese Huntington's disease and the DNA markers D4S10 and D4S43/S127. With use of the HindIII, BglI, and EcoRI polymorphisms detected at D4S10, and the combination of all these polymorphisms to give composite haplotypes, nine Japanese Huntington's disease families were found to be informative. Three recombinants for D4S10 were detected in these families, giving a maximum lod score of 1.662 at a of 0.10. Similarly, when we used the MspI and PvuII polymorphisms detected by D4S43/S127, five families gave informative results. No recombinant was detected in these families, giving a maximum lod score of 3.348 at a of 0.00. These results clearly support the view that the Japanese Huntington's disease gene may be identical with the Western gene, in spite of the lower prevalence rate in Japan.  相似文献   
7.
Summary A 444leucine to proline mutation detected by a NciI polymorphism in the human glucocerebrosidase gene was studied to investigate the correlation of the three clinical phenotypes of Gaucher disease with this mutation in 11 Japanese patients with Gaucher disease (type I, 8 patients; type II, 1 patient; type III, 2 patients) and to determine the feasibility of the use of genomic probe DNA for carrier detection and prenatal diagnosis in 8 Japanese families with Gaucher disease and agreeable to family study (type I, 6 families; type III, 2 families). The homoallelic 444leucine to proline mutation was found only in patients with type I disease. Of the 8 type I patients, 5 had the homoallelic mutation and 2 had one mutant allele. One patient with type II disease did not have this mutant allele. Of the 2 type III patients, one had a single mutant allele whereas the other exhibited no mutation of this kind. These results suggest that the 444leucine to proline mutation is very common in the type I (non-neuronopathic form) disease and is not tightly associated only with neuronopathic types of Gaucher disease in Japanese patients. These findings seem to conflict with others showing that this mutation is partially responsible for the occurrence of neuronopathic Gaucher disease. Thus, the NciI polymorphism will not be useful for the diagnosis of subtypes of Gaucher disease. Carrier detection was feasible in three families with type I disease of the 8 families analyzed by the NciI polymorphism.  相似文献   
8.
Binding affinities of modified steroidal anthrasteroids, 3 beta-hydroxy-3a beta,6-dimethyl-2,3,3a,4,5,8,9,10,10a beta,11,11a beta, 11b alpha-dodecahydro-1H-cyclopenta[a]anthracene-8-one (1) and 3a beta,6-dimethyl-2,3,3a,4,5,8,9,10,10a beta,11,11a beta,11b alpha-dodecahydro-1H-cyclopenta[a]anthracene-3,8-dione (2), the steroid oxendolone and the nonsteroid AA560, for the androgen receptor (AR) of Shionogi carcinoma 115 (SC115) and their effects on the growth of SC115 were investigated in vivo and in vitro. The inhibitory effects of these compounds on testosterone 5 alpha-reductase of SC115 tissues were also measured. The relative binding affinities of these compounds were 3.17-0.03% of that of dihydrotestosterone, and their rank order was (1) greater than AA560 greater than oxendolone much greater than (2). In the presence of 10(-9) M testosterone, anthrasteroids and AA560 inhibited the growth of SC115 cells at 10(-7) M in a serum-free medium, but oxendolone did not. In the absence of testosterone, (1), (2) and oxendolone promoted cell growth at 10(-6), 10(-7) and 10(-7) M, respectively. However, AA560 nearly completely blocked cell growth at 10(-5) M. At a 2 mg daily dose for 13 days, (1) and AA560 powerfully inhibited tumor growth in castrated DS mice treated with testosterone propionate but oxendolone had almost no effect. Anthrasteroids and oxendolone showed weak but significant agonistic activity in vivo. Anthrasteroids markedly inhibited 5 alpha-reductase activity of SC115, oxendolone weakly and AA560 not at all. The remarkable antiandrogenic activities of (1) and AA560 may partially result from their higher affinities for the AR of SC115 but other yet unknown mechanisms may also contribute to these activities.  相似文献   
9.
To explore the potential use of a nucleoside analog, N4-aminocytidine, in studies of cellular biology, the mechanism of mutation induced by this compound in mouse FM3A cells in culture was studied. On treatment of cells in suspension with N4-aminocytidine, the mutation to ouabain resistance was induced. The major DNA-replicating enzyme in mammalian cells, DNA polymerase alpha, was used to investigate whether the possible cellular metabolite of N4-aminocytidine, N4-aminodeoxycytidine 5'-triphosphate (dCamTP), can be incorporated into the DNA during replication. Using [3H]dCamTP in an in vitro DNA-synthesizing system, we were able to show that this nucleotide analog can be incorporated into newly formed DNA and that it can serve as a substitute for either dCTP or dTTP. dCamTP in the absence of dCTP maintained the activated calf thymus DNA-directed polymerization of deoxynucleoside triphosphates as efficiently as in its presence. Even in the presence of dCTP, dCamTP was incorporated into the polynucleotide. When dCamTP was used as a single substrate in the poly(dA)-oligo(dT)-directed polymerase reaction, it was incorporated into the polynucleotide fraction. The extent of incorporation was 4% of that of dTTP incorporation when dTTP was used as a single substrate. Even in the presence of dTTP, dCamTP incorporation was observed. A copolymer containing N4-aminocytosine residues was shown to incorporate guanine residues opposite the N4-aminocytosines. However, we were unable to observe adenine incorporation opposite N4-aminocytosine in templates. These cell-free experiments show that an AT-to-GC transition can take place in the presence of dCamTP during DNA synthesis, strongly suggesting that the mutation induced in the FM3A cells by N4-aminocytidine is due to replicational errors.  相似文献   
10.
Summary A tumor growth inhibitory factor (TGIF) was induced in the culture supernatant from mixed culture of human peripheral blood mononuclear cells (PBMC) and a streptococcal preparation, OK-432, in vitro. The activity generated in the supernatant increased in a time-dependent fashion and first appeared 6 h after the initiation of culture, reaching its maximum around 48 h. The TGIF was cytostatic against seven of ten human tumor targets, but not against three murine tumor targets. Tumor cell growth was inhibited by a transient contact, i.e., 1 h, with TGIF. The TGIF was produced by lymphocytes but not by monocytes, because the activity was usually enhanced by elimination of plastic-adherent cells from the original PBMC fraction. The TGIF was relatively stable against heating at 56° C for 30 min, but the activity was totally destroyed after heating at 70° C for 5 min. The molecular weight of TGIF was estimated to be about 43×103 daltons by gel filtration. No interferon (IFN) activity was detected in the TGIF-positive fractions obtained by gel filtration, and the TGIF-positive fractions did not inhibit the growth of tumor necrosis factor (TNF)-sensitive mouse L929 cells. The TGIF activity was not significantly affected in neutralizing tests using specific antibodies against human IFN and TNF. The OK-432 was administered i.p. for management of cancer patients with malignant ascites. Ascites-derived mononuclear cells (ASMC) were obtained before and 3 to 5 days after OK-432 injection. The ASMC obtained after the injection produced TGIF in vitro in the absence of OK-432; the preinjection ASMC showed no such production. A positive correlation was found between TGIF-producing activity by ASMC and the effect of OK-432 injection on ascites volume. These results indicate that TGIF is induced in mononuclear cells by OK-432 not only in vitro but also in vivo and plays an important role in inhibition of tumor growth in cancer patients.  相似文献   
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