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991.
Junko Mori Akiko Kawabata Huamin Tang Kenjiro Tadagaki Hiroyuki Mizuguchi Kazumichi Kuroda Yasuko Mori 《PloS one》2015,10(9)
The human herpesvirus-6 (HHV-6) infection induces cell-cycle arrest. In this study, we found that the HHV-6-encoded U14 protein induced cell-cycle arrest at G2/M phase via an association with the cellular protein EDD, a mediator of DNA-damage signal transduction. In the early phase of HHV-6 infection, U14 colocalized with EDD dots in the nucleus, and similar colocalization was also observed in cells transfected with a U14 expression vector. When the carboxyl-terminal region of U14 was deleted, no association of U14 and EDD was observed, and the percentage of cells in G2/M decreased relative to that in cells expressing wild-type U14, indicating that the C-terminal region of U14 and the U14–EDD association are critical for the cell-cycle arrest induced by U14. These results indicate that U14 is a G2/M checkpoint regulator encoded by HHV-6. 相似文献
992.
Yasuko Yoshinaka Satoko Soga Keiichi Yokoyama Yosuke Yamada Misaka Kimura 《Bioscience, biotechnology, and biochemistry》2018,82(4):677-682
AbstractThis study aimed to investigate the efficacy of home-based, light gymnastic exercise plus dietary milk fat globule membrane (MFGM) intake on physical fitness of an elderly Japanese sample in a pilot, double-blind, randomized, placebo-controlled trial. Seventy-one subjects (male, n = 13; female, n = 58) were randomly assigned into two groups: placebo (n = 35 [male, n = 6; female, n = 29]) and MFGM group (n = 36 [male, n = 7; female, n = 29]). The intervention was eight weeks. Subjects ingested either MFGM (1 g/day) or placebo tablets daily and engaged in an exercise program daily. Physical function tests were performed at baseline and after four and eight weeks. Foot tapping and open–close stepping scores significantly increased from baseline to eight weeks in the MFGM group. Study results suggest daily MFGM ingestion might further enhance the effects of light-intensity exercise in healthy elderly people. 相似文献
993.
We identified two key amino acid residues within human CD134 (hCD134) that are required for its interaction with human herpesvirus 6B (HHV-6B) and for HHV-6B entry into cells. One of the residues (K79) allows access of the HHV-6B ligand to hCD134. Murine CD134 (mCD134) functioned as an HHV-6B receptor when these two amino acid residues were replaced with homologous human residues. This study identifies both the HHV-6B receptor-ligand interaction and the species-specific determinants of hCD134 essential for HHV-6B entry. 相似文献
994.
995.
996.
Oyaizu H Tang H Ota M Takenaka N Ozono K Yamanishi K Mori Y 《Journal of virology》2012,86(16):8492-8498
Human herpesvirus 6 (HHV-6) is a T-cell-tropic betaherpesvirus. HHV-6 can be classified into two variants, HHV-6 variant A (HHV-6A) and HHV-6B, based on genetic, antigenic, and cell tropisms, although the homology of their entire genomic sequences is nearly 90%. The HHV-6A glycoprotein complex gH/gL/gQ1/gQ2 is a viral ligand that binds to the cellular receptor human CD46. Because gH has 94.3% amino acid identity between the variants, here we examined whether gH from one variant could complement its loss in the other. Recently, we successfully reconstituted HHV-6A from its cloned genome in a bacterial artificial chromosome (BAC) (rHHV-6ABAC). Using this system, we constructed HHV-6ABAC DNA containing the HHV-6B gH (BgH) gene instead of the HHV-6A gH (AgH) gene in Escherichia coli. Recombinant HHV-6ABAC expressing BgH (rHHV-6ABAC-BgH) was successfully reconstituted. In addition, a monoclonal antibody that blocks HHV-6B but not HHV-6A infection neutralized rHHV-6ABAC-BgH but not rHHV-6ABAC. These results indicate that HHV-6B gH can complement the function of HHV-6A gH in the viral infectious cycle. 相似文献
997.
The antiproliferative effects of agmatine correlate with the rate of cellular proliferation 总被引:1,自引:0,他引:1
Isome M Lortie MJ Murakami Y Parisi E Matsufuji S Satriano J 《American journal of physiology. Cell physiology》2007,293(2):C705-C711
Polyamines are small cationic molecules required for cellular proliferation. Agmatine is a biogenic amine unique in its capacity to arrest proliferation in cell lines by depleting intracellular polyamine levels. We previously demonstrated that agmatine enters mammalian cells via the polyamine transport system. As polyamine transport is positively correlated with the rate of cellular proliferation, the current study examines the antiproliferative effects of agmatine on cells with varying proliferative kinetics. Herein, we evaluate agmatine transport, intracellular accumulation, and its effects on antizyme expression and cellular proliferation in nontransformed cell lines and their transformed variants. H-ras- and Src-transformed murine NIH/3T3 cells (Ras/3T3 and Src/3T3, respectively) that were exposed to exogenous agmatine exhibit increased uptake and intracellular accumulation relative to the parental NIH/3T3 cell line. Similar increases were obtained for human primary foreskin fibroblasts relative to a human fibrosarcoma cell line, HT1080. Agmatine increases expression of antizyme, a protein that inhibits polyamine biosynthesis and transport. Ras/3T3 and Src/3T3 cells demonstrated augmented increases in antizyme protein expression relative to NIH/3T3 in response to agmatine. All transformed cell lines were significantly more sensitive to the antiproliferative effects of agmatine than nontransformed lines. These effects were attenuated in the presence of exogenous polyamines or inhibitors of polyamine transport. In conclusion, the antiproliferative effects of agmatine preferentially target transformed cell lines due to the increased agmatine uptake exhibited by cells with short cycling times. polyamines; antizyme; ornithine decarboxylase; polyamine transport 相似文献
998.
Suzuki T Semba S Sunden Y Orba Y Kobayashi S Nagashima K Kimura T Hasegawa H Sawa H 《Microbiology and immunology》2012,56(9):639-646
JC virus (JCV) belongs to the polyomavirus family of double-stranded DNA viruses and causes progressive multifocal leukoencephalopathy in humans. JCV encodes early proteins (large T antigen, small T antigen, and T' antigen) and four late proteins (agnoprotein, and three viral capsid proteins, VP1, VP2, and VP3). In the current study, a novel function for JCV agnoprotein in the morphogenesis of JC virion particles was identified. It was found that mature virions of agnoprotein-negative JCV are irregularly shaped. Sucrose gradient sedimentation and cesium chloride gradient ultracentrifugation analyses revealed that the particles of virus lacking agnoprotein assemble into irregularly sized virions, and that agnoprotein alters the efficiency of formation of VP1 virus-like particles. An in vitro binding assay and immunocytochemistry revealed that agnoprotein binds to glutathione S-transferase fusion proteins of VP1 and that some fractions of agnoprotein colocalize with VP1 in the nucleus. In addition, gel filtration analysis of formation of VP1-pentamers revealed that agnoprotein enhances formation of these pentamers by interacting with VP1. The present findings suggest that JCV agnoprotein plays a role, similar to that of SV40 agnoprotein, in facilitating virion assembly. 相似文献
999.
Yasuko Takeda 《Carbohydrate research》1979,77(1):9-23
Condensation products of isonicotino- and benzo-hydrazide, and p-bromophenylhydrazine with d-glucose, d-mannose, d-arabinose, and d-ribose, respectively, and of isonicotinohydrazide with sodium d-glucuronate, d-glucofuranurono-6,3-lactone, and d-glyceraldehyde were prepared. The structure of the compounds in solution was examined by 1H- and 13C-n.m.r. spectroscopy and optical rotation, and in solid state by i.r. spectroscopy. The study of the anomerization and ring-chain interconversion on solutions in various solvents showed that both anomerization and interconversion depend upon the sugar configuration, basicity of the hydrazine group, and proton-acceptor ability of the solvent. 相似文献
1000.
The hydrophobicity of myelinic, synaptosomal and mitochondrial surfaces in the rat brain was measured using the nonionic surfactant, C18H37O(CH2CH2O)13H. This method is based on the adsorption of the hydrophobic alkyl group of the surfactant by the hydrophobic sites on the surfaces. Each preparations was mixed with an excess of the surfactant and the surfactant remaining in the supernatants was determined spectrophotometrically by measuring the absorbance of tetrabromophenolphthalein ethylester at 690 nm. The greatest amount was adsorbed by myelin, followed by synaptosomes and mitochondria. The hydrophobicity is shown to be a reflection of the surface lipids. This method showed good reproducibility and was useful for the quantitative determination of hydrophobicity. 相似文献