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1.
2.
A fibroblast-derived tumor cytotoxic factor/F-TCF (hepatocyte growth factor/HGF) has multiple functions in vitro. 总被引:2,自引:0,他引:2
N Shima Y Itagaki M Nagao H Yasuda T Morinaga K Higashio 《Cell biology international reports》1991,15(5):397-408
We previously demonstrated that a tumor cytotoxic factor(F-TCF) purified from the culture broth of human embryonic lung diploid fibroblast, IMR-90 cells was one of the human hepatocyte growth factors (hHGFs). In the present report, we demonstrate its biological functions. F-TCF showed moderate cytotoxicity on human tumor cell lines KB, BG-1, MCF-7 and Hs913 T, and strong cytotoxicity on mouse tumor cell lines Sarcoma 180, Meth A sarcoma and P388. On the contrary, F-TCF was a potent mitogen not only for adult rat hepatocytes, but also for human endothelial cells, HUVEC and human melanocytes. Moreover, F-TCF induced the differentiation of premyelocyte leukemia, HL-60 cells into morphologically granulocyte-like cells. These biological functions suggest that F-TCF is an effector molecule responsible for inflammation and repair in injured tissues including tumor and liver. 相似文献
3.
The human alpha-fetoprotein gene. Sequence organization and the 5' flanking region 总被引:12,自引:0,他引:12
M Sakai T Morinaga Y Urano K Watanabe T G Wegmann T Tamaoki 《The Journal of biological chemistry》1985,260(8):5055-5060
The human alpha-fetoprotein (AFP) gene was isolated into three overlapping clones in bacteriophage lambda vectors and its sequence organization analyzed by restriction endonuclease mapping and nucleotide sequencing. The human AFP gene is about 20 kilobase pairs long and contains 15 exons and 14 introns. The overall organization of the human AFP gene is similar to that of the mouse AFP gene, with all but two exons showing identical sizes. Nucleotide sequences at all exon/intron junctions display similarity to the consensus boundary sequence (Breathnach, R., and Chambon, P. (1981) Annu. Rev. Biochem. 50, 349-383), with the GT-AG rule applied to the splicing point. The cap site maps 44 nucleotides upstream from the translation initiation site. The "TATA box" is located 27 nucleotides upstream from the putative cap site and is flanked by sequences with dyad symmetry. The TATA box can thus be placed in the loop portion of a possible stem-loop structure formed by intrastrand base-pairing. Other characteristic nucleotide sequences in the 5' flanking region include a CCAAC pentamer, a 14-base pair (bp) enhancer-like sequence, and a 9-bp sequence homologous to the glucocorticoid responsive element. A long (90 bp) direct repeat and several alternating purine/pyrimidine sequences are also present in the 5' flanking region. A 736-bp sequence of the 5' flanking region adjacent to the cap site of the human AFP gene shows a 61% similarity with the corresponding region of the mouse AFP gene. There are two Alu family sequences and two poly(dT-dG) repeats in the human AFP gene that show different distribution patterns from those in the mouse AFP gene. 相似文献
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The fungal succession on pine cones on the floor ofPinus densiflora forest was investigated in the early decomposition process (within ca. 30% decrease in dry weight). The fungal flora was examined by both washing and surface-sterilization methods on artificially placed cones and naturally fallen cones. The decomposition rates of artificially placed cones were 0.081–0.082 yr–1. On withered cones still attached to the tree,Pestalotiopsis spp. were dominant. These fungi also occurred with higher frequencies after cones had lain on the floor and on cones in the L and FH horizons.Xylaria sp. andPhomopsis sp., which seem to colonize the interior of the tissue, occurred with higher frequencies on the cones on the tree, but their occurrence frequencies decreased after cones had lain on the forest floor. Conversely,Mortierella spp. andTrichoderma spp. newly occurred or their occurrence frequencies increased on lying cones. Of these,Trichoderma koningii increased rapidly and showed high occurrence frequencies.Thysanophora penicillioides, which prefers coniferous substrates, showed higher occurrence frequencies in the early stages of lying on the forest floor. On cones lying on the floor, the fungal flora did not significantly change during the investigation period. 相似文献
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Yoko Ino Yutaro Yamaoka Kiho Tanaka Kei Miyakawa Mayuko Nishi Yasuyoshi Hatayama Hirokazu Kimura Yayoi Kimura Akihide Ryo 《Proteomics》2023,23(11):2200334
Peptide tag systems are a robust biophysical and biochemical method that is widely used for protein detection and purification. Here, we developed a novel tag system termed “HiP4” (histidine plus four amino acids) whose epitope sequence comprises only seven amino acids (HHHDYDI) that partially overlap with the conventional 6x histidine tag (6xHis-tag). We produced a monoclonal antibody against the HiP4 tag that can be used in multiple immunoassays with high specificity and affinity. Using this system, we developed a tandem affinity purification (TAP) and mass spectrometry (TAP-MS) system for comprehensive protein interactome analysis. The integrated use of nickel bead purification followed by HiP4 tag immunoprecipitation made it possible to reduce nonspecific binding and improve selectivity, leading to the recovery of previously unrecognized proteins that interact with hepatitis B virus X (HBx) protein or TAR DNA-binding protein 43 (TARDBP or TDP-43). Our results indicate that this system may be viable as a simple and powerful tool for TAP-MS that can achieve low background and high selectivity in comprehensive protein–protein interaction analyses. 相似文献
8.
Summary Examination was made of the structure and assembly of the cortical microtubule (MT) cytoskeleton in the coenocytic green algaBoodlea coacta (Dickie) Murray et De Toni by immunofluorescence microscopy. Cortical MTs inBoodlea protoplasts are arranged randomly but some show a meridional arrangement within 6 h after protoplast formation. At 6–9 h such MTs become highly concentrated and parallel to each other in certain areas. At 12 h the concentration is uniformly high throughout the cell, indicating the completion of high density meridional arrangement of cortical MTs. Cortical MTs exhibiting a high density, meridional arrangement show characteristic disassembly by treatment with 10 M amiprophos-methyl (APM) or cold treatment (0 °C). Disassembly occurs by each MT unit at positions skipping 30–40 m in the transverse direction, and neighboring MTs subsequently disassemble to form MT groups. Each group becomes slender and then disappears completely within the following 24 h. The meridional arrangement of cortical MTs is disrupted by N-ethylmaleimide (NEM) accompanied by a remarkable reduction in density. The remaining MTs form groups at 30–40 m intervals from each other, as also occurs with drug or cold treatment, but disruption and density return to normal levels following removal of NEM. It appears that there are meridionally oriented channels, anchor-rich and anchor-poor, in the plasma membrane. The channels could be distributed alternately and anchors could be deposited in a cross-linking manner with cortical MTs to form a stable cortical MT-cytoskeleton. MTs comprising the cortical MT cytoskeleton could be oriented by meridionally oriented channels of anchors which are distributed following establishment of cell polarity.Abbreviations APM
amiprophos-methyl
- MT
microtubule
- MTOC
microtubule organizing center
- NEM
N-ethylrnaleimide 相似文献
9.
10.
Identity of a tumor cytotoxic factor from human fibroblasts and hepatocyte growth factor 总被引:20,自引:0,他引:20
K Higashio N Shima M Goto Y Itagaki M Nagao H Yasuda T Morinaga 《Biochemical and biophysical research communications》1990,170(1):397-404
Human embryonic lung diploid fibroblast, IMR-90 cells secreted a tumor cytotoxic factor. The fibroblast-derived tumor cytotoxic factor (F-TCF) has a cytotoxic activity to Sarcoma 180 and a cytostatic and degenerative activities to KB cells. F-TCF has been purified about 540,000-fold with 23.3% recovery from 75 liters of the conditioned medium containing 5% newborn calf serum. The purified F-TCF is a basic glycoprotein with isoelectric point values of 7.4 to 8.6. It was stable in the pH range from 6.0 to 9.0 and was stable at the heating temperature of 60 degrees C for 10 min, but completely inactivated by reducing it with 2-mercaptoethanol. F-TCF has molecular weight of 76 to 80 kD on SDS-PAGE under non-reducing conditions and is a heterodimer consisting of a large alpha subunit with 52 to 56 kD and a small beta subunit with 30 to 34 kD. F-TCF was identified as one of human hepatocyte growth factors by the physicochemical properties including N terminal and a few internal amino acid sequences. We have confirmed that F-TCF has an ability to dramatically stimulate DNA synthesis in adult rat hepatocytes in the low dose range of 1 to 10 ng/ml. 相似文献