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1.
Induction of erythroid differentiation by cytoplast fusion in mouse erythroleukemia (Friend) cells 总被引:6,自引:0,他引:6
An intracellular activity, which is induced by dimethyl sulfoxide (DMSO) or hexamethylenebisacetamide (HMBA) and leads to erythroid differentiation in mouse Friend cells, was characterized by cell fusion between genetically marked intact cells and cytoplasts. For this, a procedure for rapid selection of cybrids was devised by sensitizing non-fused cells with oligomycin. We were able to demonstrate that cytoplasts derived from DMSO- (or HMBA)-treated cells trigger erythroid differentiation upon fusion with UV-irradiated cells. The activity in the cytoplasts remained only transiently and its induction was inhibited by biologically active phorbol esters or cycloheximide. The activity, however, was not induced in cytoplasts by directly treating them with DMSO (or HMBA). These results indicate that (1) the intracellular erythroid-inducing activity is located in cytoplasts, (2) it acts in trans and induces erythroid differentiation as a dominant factor and (3) its production requires de novo nuclear protein synthesis. The mechanisms of the induction of the intracellular activity and of how it triggers erythroid differentiation are discussed. 相似文献
2.
H Karibe K Oishi M K Uchida 《Biochemical and biophysical research communications》1991,179(1):487-494
The contribution of protein kinase C to the contraction by oxytocin of rat uterine longitudinal smooth muscle in Ca(2+)-free solution was investigated. Immunological analysis revealed that type II (beta) and III (alpha) protein kinase C subspecies were present in rat uterine smooth muscle. The pretreatment of a diacylglycerol kinase inhibitor R59022 to accumulate diacylglycerol potentiated the Ca(2+)-independent contraction. The contractile activity was diminished with the depletion of protein kinase C, when the contraction was evoked repeatedly by oxytocin during the prolonged exposure to a tumor-promoting phorbol ester 12-O-tetradecanoylphorbol 13-acetate. These results suggested the involvement of protein kinase C in oxytocin-induced contraction in Ca(2+)-free solution. 相似文献
3.
Masayoshi Takahashi Hiroshi Yokota Dai Ayusawa Michio Oishi Tetsuo Kunieda 《Biochemical genetics》1992,30(9-10):537-544
A novel restriction fragment length polymorphism (RFLP) in inbred rats was revealed by Southern blot analysis with a clone arbitrarily chosen from a rat genomic library as a probe. A clone named alpha 403 showed interstrain variations in the length of the EcoRI and HindIII fragments. The EcoRI fragments were either 0.7 or 3 kb, those of HindIII were either 4.5 or 5 kb, and three types were identified as combinations of those fragments in 20 inbred rat strains. These types segregated in backcross progeny as codominant alleles. The locus for the RFLP was thus named A403. Analysis of linkage between the RFLP locus and 13 other loci reveal that the A403 locus was closely linked to the Cs-1 locus (15 +/- 5.2%), which belongs to rat linkage group XIII. 相似文献
4.
UV Irradiation induces an activity which stimulates Simian virus 40 rescue upon cell fusion. 总被引:8,自引:5,他引:3 下载免费PDF全文
UV irradiation of African green monkey cells greatly stimulated efficiency of simian virus 40 induction from simian virus 40-transformed Syrian hamster cells after cell fusion. The maximum inducing activity was observed at 15 to 20 h after irradiation but remained only transiently. The addition of cycloheximide after UV irradiation eliminated the stimulation of the activity. 相似文献
5.
K Oishi J Imanishi T Kishida 《Comptes rendus des séances de la Société de biologie et de ses filiales》1979,173(5):1000-1003
The preparations of interferon or virus-inhibiting factor produced in L cell (L-IF) and mouse brain (MB-IF) enhanced the killing of Staphylococcus aureus (S.a.) by the mouse peritoneal macrophage. The L-IF, heat-inactivated at 80 degrees or 60 degrees for 30 min., and mock L-IF could not enhance the killing of S.a. The heterologous human and rabbit interferon preparations didn't enhance the bactericidal activity of macrophage. The L-IF didn't have any effect on the release of lysozyme from the macrophages. 相似文献
6.
Stereochemical structure recognized by the L-fucose-specific hemagglutinin produced by Streptomyces sp 总被引:1,自引:0,他引:1
A hemagglutinin has been purified 4000-fold from the culture filtrate of a strain of Streptomyces by affinity chromatography. The purified preparation was judged to be homogeneous by gel electrophoresis and its molecular weight was estimated to be about 70 000 by sodium dodecyl sulfate polyacrylamide gel electrophoresis. It may exhibit its full hemagglutinating activity in the monomer form. This hemagglutinin strongly agglutinated human blood group O erythrocytes and was inhibited by L-fucose. It was, however, distinct from the known L-fucose-specific hemagglutinins; first, the hemagglutinating activity of the purified preparation was more than 100-times stronger than that of others; second, D-mannose was a potent inhibitor of this hemagglutinin besides L-fucose but not or scarcely inhibitory to others; and third, p-nitrophenyl-beta-L-fucoside was more inhibitory to this hemagglutinin than p-nitrophenyl-alpha-L-fucoside as opposed to the case of others. 相似文献
7.
Tsukasa Mizuhara Shinya Oishi Hiroaki Ohno Kazuya Shimura Masao Matsuoka Nobutaka Fujii 《Bioorganic & medicinal chemistry》2013,21(7):2079-2087
To investigate the mechanism of action of the potent antiviral compound PD 404182, three novel photoaffinity probes equipped with a biotin or alkyne indicator were designed and synthesized based on previous structure–activity relationship studies. These probes retained the potent anti-HIV activity of the original pyrimidobenzothiazine derivatives. In photoaffinity labeling studies using HIV-1-infected H9 cells (H9IIIB), eight potential proteins were observed to bind PD 404182. 相似文献
8.
Landscape and Ecological Engineering - Japanese gardens play an important role in the conservation of bryophyte diversity. Previous studies have indicated that diverse garden landscapes and their... 相似文献
9.
Takeda N Maemura K Horie S Oishi K Imai Y Harada T Saito T Shiga T Amiya E Manabe I Ishida N Nagai R 《The Journal of biological chemistry》2007,282(45):32561-32567
Cardiovascular diseases are closely related to circadian rhythm, which is under the control of an internal biological clock mechanism. Although a biological clock exists not only in the hypothalamus but also in each peripheral tissue, the biological relevance of the peripheral clock remains to be elucidated. In this study we searched for clock-controlled genes in vascular endothelial cells using microarray technology. The expression of a total of 229 genes was up-regulated by CLOCK/BMAL2. Among the genes that we identified, we examined the thrombomodulin (TM) gene further, because TM is an integral membrane glycoprotein that is expressed primarily in vascular endothelial cells and plays a major role in the regulation of intravascular coagulation. TM mRNA and protein expression showed a clear circadian oscillation in the mouse lung and heart. Reporter analyses, gel shift assays, and chromatin immunoprecipitation analyses using the TM promoter revealed that a heterodimer of CLOCK and BMAL2 binds directly to the E-box of the TM promoter, resulting in TM promoter transactivation. Indeed, the oscillation of TM gene expression was abolished in clock mutant mice, suggesting that TM expression is regulated by the clock gene in vivo. Finally, the phase of circadian oscillation of TM mRNA expression was altered by temporal feeding restriction, suggesting TM gene expression is regulated by the peripheral clock system. In conclusion, these data suggest that the peripheral clock in vascular endothelial cells regulates TM gene expression and that the oscillation of TM expression may contribute to the circadian variation of cardiovascular events. 相似文献
10.