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1.
2.
Osafune Tetsuaki; Mihara Sayoko; Hase Eiji; Ohkuro Isamu 《Plant & cell physiology》1972,13(2):211-227
Changes in subcellular structures during the entire vegetativecell cycle of Chlamydomonas reinhardi Dangeard in synchronousculture were followed with an electron microscope. Giant mitochondriaof various shapes were temporarily formed, probably by fusionof smaller mitochondria, in the algal cells at an intermediatestage of the growth phase of the cell cycle. Formation of giantmitochondria was accompanied by a marked decrease in the oxygen-uptakeactivity of cells. Giant mitochondria divided into smaller formsconcurrently with a re-increase in the oxygen-uptake activityof cells. Some characteristics of changes in the structuresof chloroplast, the nucleus, the endoplasmic reticula, flagellaand dictyosomes are described.
1 This work was reported in part at the 35th Annual Meetingof the Botanical Society of Japan, October 1970. (Received October 13, 1971; ) 相似文献
3.
Chromatin was prepared from the buds and cotyledons of Alaskapea seedlings. The dissociated chromosomal components in thepresence of 2 M NaCl and 5 M urea were completely fractionatedinto DNA and proteins with a Bio-Gel A50 column. The proteinswere recovered by (NH4)2SO4 and further fractionated into histonesand non-histone proteins using a Bio-Rex 70(Na+) column. Thedifference in the ratios of histones to non-histone proteinsbefore and after chromatography with the Bio-Rex 70 was lessthan 10%. The histones and non-histone proteins thus preparedshowed typical protein absorption spectra. Polyacrylamide gelelectrophoresis of histones showed that the histone compositionsin buds and cotyledon were similar, but the amount of HI histoneswas a little less in cotyledons than in buds. Unlike histones,non-histone proteins fractionated by SDS-polyacrylamide gelelectrophoresis indicated distinct differences between the twotissues. Buds had more heterogeneous non-histone proteins, atleast 13 polypeptides, than cotyledons did. On the other hand,non-histone proteins of cotyledons showed less heterogeneityand lacked proteins of high molecular weight which were foundin buds. (Received May 6, 1976; ) 相似文献
4.
Jun Iwaki Kunio Kikuchi Yoshiaki Mizuguchi Yutaka Kawahigashi Hiroshi Yoshida Eiji Uchida Toshihiro Takizawa 《PloS one》2013,8(7)
MicroRNA miR-376c was expressed in normal intrahepatic biliary epithelial cells (HIBEpiC), but was significantly suppressed in the HuCCT1 intrahepatic cholangiocarcinoma (ICC) cell line. The biological significance of the down-regulation of miR-376c in HuCCT1 cells is unknown. We hypothesized that miR-376c could function as a tumor suppressor in these cells. To test this hypothesis, we sought the targets of miR-376c, and characterized the effect of its down-regulation on HuCCT1 cells. We performed proteomic analysis of miR-376c-overexpressing HuCCT1 cells to identify candidate targets of miR-376c, and validated these targets by 3′-UTR reporter assay. Transwell migration assays were performed to study the migratory response of HuCCT1 cells to miR-376c overexpression. Furthermore, microarrays were used to identify the signaling that were potentially involved in the miR-376c-modulated migration of HuCCT1. Finally, we assessed epigenetic changes within the potential promoter region of the miR-376c gene in these cells. Proteomic analysis and subsequent validation assays showed that growth factor receptor-bound protein 2 (GRB2) was a direct target of miR-376c. The transwell migration assay revealed that miR-376c significantly reduced epidermal growth factor (EGF)-dependent cell migration in HuCCT1 cells. DNA microarray and subsequent pathway analysis showed that interleukin 1 beta and matrix metallopeptidase 9 were possible participants in EGF-dependent migration of HuCCT1 cells. Bisulfite sequencing showed higher methylation levels of CpG sites upstream of the miR-376c gene in HuCCT1 relative to HIBEpiC cells. Combined treatment with the DNA-demethylating agent 5-aza-2′-deoxycytidine and the histone deacetylase inhibitor trichostatin A significantly upregulated the expression of miR-376c in HuCCT1 cells. We revealed that epigenetic repression of miR-376c accelerated EGF-dependent cell migration through its target GRB2 in HuCCT1 cells. These findings suggest that miR-376c functions as a tumor suppressor. Since metastasis is the major cause of death in ICC, microRNA manipulation could lead to the development of novel anti-cancer therapy strategies for ICC. 相似文献
5.
Eiji Niwa En-Sheng Chen Satoshi Kanoh Teruo Nakayama 《Bioscience, biotechnology, and biochemistry》2013,77(11):3067-3071
The linearity of the stress-strain relationship for food gel is limited to a very narrow range of the strain (usually less than 0.1 as a Cauchy measure). The reason is thought due to the change in cross-sectional area of the gel upon deformation. In this report, the cross-sectional area was approximately corrected of the compressed gel on the assumption that the gel expanded uniformly without changing its volume upon compression. In cases when the initial Young’s modulus was calculated from the thus-corrected area for some food gels, the linearity was increased for a wider range of strain. 相似文献
6.
Kaeko Tozawa Eiji Arakawa Toshiyuki Chikuma Yoshihiro Oh-hashi Ryuichi Yajima Katsumichi Takeda Hiroshi Shinozaki† Takeshi Kato† 《Journal of neurochemistry》1990,55(3):745-749
Axonal transport of peptidylglycine alpha-amidating monooxygenase (PAM) activity was studied in rat sciatic nerves from 12 to 120 h after double ligations. The anterograde axonal transport increased and reached a plateau between 48 and 72 h and then decreased. The flow rate was 100 mm/day, and the molecular mass of the active entity was 70 kDa, which was determined by gel filtration. In contrast, there was no evidence for significant retrograde axonal transport. Anterograde axonal transport of immunoreactive cholecystokinin, a carboxy-terminal-amidated putative neuropeptide, was also found. These results suggest that PAM is transported by a rapid axonal flow and may play a role as a processing enzyme during transport or in the terminals of rat sciatic nerves. 相似文献
7.
Shigeru Kumano Masashi Ihira Yasuo Maeda Misako Yamauchi Eiji Matsumoto Isao Matsuda 《Ecological Research》1990,5(2):221-235
Diatom assemblages of sediments obtained from three sites on Kushiro Moor were analyzed to investigate the Holocene sedimentary
history. The results showed that: 1) The Takkobu site was originally at the bottom of the paleo-Kushiro Bay, and after-wards
the paleo-Takkobu Lagoon developed, became sealed off, and changed to a freshwater lake. The succession to peat moor probably
began about 2000 yr B.P. at the Takkobu site. 2) The Tsurui site was originally at the bottom of the paleo-Kushiro Bay, then
changed to the paleo-Kushiro Lagoon and became peat moor as a result of the first Holocene regression, which finished about
3600 yr B.P. The site then returned to a brackish lake again, probably due to the second Holocene transgression between 3600
and 3000 yr B.P., thereafter passing through brackish lake and freshwater lake stages, and eventually becaming peat moor at
about 2000 yr B.P., 3) At the Chuo site, the second paleo-Kushiro Bay developed again as a result of the second Holocene transgression,
which finished about 3000 yr B.P. Thereafter, brackish or freshwater lakes, rivers, and then peat moor developed in the central
area of Kushiro Moor. 4) The second marine diatom zone (MD2 Zone), which indicates the second Holocene transgression, complete by about 3000 yr B.P., is detected only at the Chuo site
in the central area of Kushiro Moor. 相似文献
8.
Summary Biosynthesis and processing of the protective protein for -galactosidase in normal and galactosialidosis fibroblasts were investigated using specific antiserum preparations. A 45-kd precursor was processed to a mature 30-kd protein in normal fibroblasts. The mature protective protein was not detected in any of the twelve galactosialidosis fibroblast strains examined in this study. The precursor was not detected in two cases and in the others was of heterogeneous molecular weight, i.e., normal, abnormally low, or abnormally high. These molecular abnormalities were not correlated with clinical manifestations of the patients. 相似文献
9.
10.
Eiji Kumazawa Akiko Tohgo Tsunehiko Soga Tsuneo Kusama Yasuaki Osada 《Cancer immunology, immunotherapy : CII》1992,35(5):307-314
Summary The antitumor effect of a synthetic lipid A analogue, DT-5461, was investigated using syngeneic tumor models in mice. Intravenous injection of DT-5461 into mice transplanted with solid tumors of MethA fibrosarcoma, MH134 hepatoma, MM46 mammary carcinoma, Lewis lung carcinoma (3LL), and colon adenocarcinomas 26 and 38 resulted in significant reductions in the weight of all tumors except Colon 26, with marked hemorrhagic necrosis of tumor tissues. Efficacy was almost equal to that of anEscherichia coli-type synthetic lipid A (compound 506), and also to those of some chemotherapeutics including Adriamycin, mitomycin C, fluorouracil and cisplatin. Furthermore, DT-5461 was more effective than other immunotherapeutics, including picibanil (OK-432) and lentinan. However, its antitumor effects were inferior to those of Adriamycin or OK-432 against the malignant ascites caused by intraperitoneal inoculation with MethA or with MH134 cells; life span was not prolonged by either intraperitoneal or intravenous administration. In addition, although DT-5461 showed direct inhibitory effects on the in vitro growth of MethA or MH134, these were much weaker than those of Adriamycin. These findings clearly indicated that DT-5461 with systemic administration is a highly effective antitumor agent on solid tumors, and suggest that the antitumor effect of DT-5461 with potent necrotizing activity might derive from indirect mechanisms related to the activation of host immune systems and not to the weak direct cytotoxicity. 相似文献