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231.
Acylated anthocyanins from red radish (Raphanus sativus L.) 总被引:5,自引:0,他引:5
Twelve acylated anthocyanins were isolated from the red radish (Raphanus sativus L.) and their structures were determined by spectroscopic analyses. Six of these were identified as pelargonidin 3-O-[6-O-(E)-feruloyl-2-O-beta-D-glucopyranosyl]-(1-->2)-beta-D-glucopyranoside]-5-O-(beta-D-glucopyranoside), pelargonidin 3-O-[6-O-(E)-caffeoyl-2-O-(6-(E)-feruloyl-beta-D-glucopyranosyl)-(1-->2)-beta-D-glucopyranoside]-5-O-(beta-D-glucopyranoside), pelargonidin 3-O-[6-O-(E)-p-coumaroyl-2-O-(6-(E)-caffeoyl-beta-D-glucopyranosyl)-(1-->2)-beta-D-glucopyranoside]-5-O-(beta-D-glucopyranoside), pelargonidin 3-O-[6-O-(E)-feruloyl-2-O-(6-(E)-caffeoyl-beta-D-glucopyranosyl)-(1-->2)-beta-D-glucopyranoside]-5-O-(beta-D-glucopyranoside), pelargonidin 3-O-[6-O-(E)-p-coumaroyl-2-O-(6-(E)-feruloyl-beta-D-glucopyranosyl)-(1-->2)-beta-D-glucopyranoside]-5-O-(beta-D-glucopyranoside), and pelargonidin 3-O-[6-O-(E)-feruloyl-2-O-(2-(E)-feruloyl-beta-D-glucopyranosyl)-(1-->2)-beta-D-glucopyranoside]-5-O-(beta-D-glucopyranoside). 相似文献
232.
Tsuji AB Sudo H Sugyo A Otsuki M Miyagishi M Taira K Imai T Harada YN 《Biochemical and biophysical research communications》2005,333(4):1370-1377
Radiotherapy can cause unacceptable levels of damage to normal tissues in some cancer patients. To understand the molecular mechanisms underlying radiation-induced physiological responses, and to be able to predict the radiation susceptibility of normal tissues in individual patients, it is important to identify a comprehensive set of genes responsible for radiation susceptibility. We have developed a simple and rapid 96-well screening protocol using cell proliferation assays and RNA interference to identify genes associated with radiation susceptibility. We evaluated the performance of alamarBlue-, BrdU-, and sulforhodamine B-based cell proliferation assays using the 96-well format. Each proliferation assay detected the known radiation susceptibility gene, PRKDC. In a trial screen using 28 shRNA vectors, another known gene, CDKN1A, and one new radiation susceptibility gene, ATP5G3, were identified. Our results indicate that this method may be useful for large-scale screens designed to identify novel radiation susceptibility genes. 相似文献
233.
Arai R Ito K Wakiyama M Matsumoto E Sakamoto A Etou Y Otsuki M Inoue M Hayashizaki Y Miyagishi M Taira K Shirouzu M Yokoyama S 《Journal of biochemistry》2004,136(4):421-425
Yeast Fis1p participates in mitochondrial fission, together with Dnm1p and Mdv1p. Recently, human Fis1 (hFis1) was reported to be involved in mitochondrial fission, together with Drp1. We established stable transformants with an hFis1 siRNA expression vector. In the stable hFis1 knockdown cells, hFis1 expression was suppressed to approximately 10%, and mitochondrial fission, induced by cisplatin treatment, was delayed. In addition, mouse Fis1 (mFis1) expression promoted mitochondrial fission and cell death in the hFis1 knockdown cells, suggesting that mFis1 complements the function of hFis1. These hFis1 siRNA expression vectors may be useful for studying the molecular function of mammalian Fis1. 相似文献
234.
Ito T Goto H Yamamoto E Tanaka H Takeuchi M Kuwayama M Kawaoka Y Otsuki K 《Journal of virology》2001,75(9):4439-4443
Highly virulent avian influenza viruses can arise from avirulent strains maintained in poultry, but evidence to support their generation from viruses in wild birds is lacking. The most likely mechanism for the acquisition of virulence by benign avian viruses is the introduction of mutations by error-prone RNA polymerase, followed by the selection of virulent viruses. To investigate whether this mechanism could apply to wild waterfowl, we studied an avirulent wild-swan virus that replicates poorly in chickens. After 24 consecutive passages by air sac inoculation, followed by five passages in chicken brain, the avirulent virus became highly pathogenic in chickens, producing a 100% mortality rate. Sequence analysis at the hemmaglutinin cleavage site of the original isolate revealed a typical avirulence type of sequence, R-E-T-R, which progressed incrementally to a typical virulence type of sequence, R-R-K-K-R, during repeated passages in chickens. These results demonstrate that avirulent viruses maintained in wild waterfowl in nature and bearing the consensus avirulence type sequence R-E-T-R have the potential to become highly pathogenic while circulating in chickens. 相似文献
235.
The effects of adding Cu-Zn superoxide dismutase (Cu-Zn SOD) to culture medium of the murine fibroblast cell line, L-929, pretreated with UV-B (312 nm, 480 mJ/cm(2)) have been investigated. Cell injury was monitored by the release of lactate dehydrogenase (LDH) into the medium, and cell death by the trypan blue exclusion test. UV-B radiation induced cell death by apoptosis, as demonstrated by DNA fragmentation. Over the range 0.1-0.3 microm Cu-Zn SOD, a significant dose-dependent protection against cell death was obtained of the UV-B exposed cells. Cell death correlated with the amount of LDH released into the medium, and Cu-Zn SOD treatment inhibited this. Heat-denatured Cu-Zn SOD did not affect either cell viability or the release of LDH from the cells. Endogenous Cu-Zn SOD activity, monitored by chemiluminescence, decreased by 20% in UV-B-irradiated cells; the addition of 0.3 microm exogenous Cu-Zn SOD to the medium did not affect intracellular Cu-Zn SOD activity. These results establish that Cu-Zn SOD added to extracellular medium can protect cells against injury caused by UV-B exposure. 相似文献
236.
Otsuki Tetsuji; Ota Toshio; Nishikawa Tetsuo; Hayashi Koji; Suzuki Yutaka; Yamamoto Jun-ichi; Wakamatsu Ai; Kimura Kouichi; Sakamoto Katsuhiko; Hatano Naoto; Kawai Yuri; Ishii Shizuko; Saito Kaoru; Kojima Shin-ichi; Sugiyama Tomoyasu; Ono Tetsuyoshi; Okano Kazunori; Yoshikawa Yoko; Aotsuka Satoshi; Sasaki Naokazu; Hattori Atsushi; Okumura Koji; Nagai Keiichi; Sugano Sumio; Isogai Takao 《DNA research》2005,12(2):117-126
We have developed an in silico method of selection of humanfull-length cDNAs encoding secretion or membrane proteins fromoligo-capped cDNA libraries. Fullness rates were increased toabout 80% by combination of the oligo-capping method and ATGpr,software for prediction of translation start point and the codingpotential. Then, using 5'-end single-pass sequences, cDNAs havingthe signal sequence were selected by PSORT (signal sequencetrap). We also applied secretion or membrane protein-relatedkeyword trap based on the result of BLAST search againstthe SWISS-PROT database for the cDNAs which could not be selectedby PSORT. Using the above procedures, 789 cDNAs were primarilyselected and subjected to full-length sequencing, and 334 ofthese cDNAs were finally selected as novel. Most of the cDNAs(295 cDNAs: 88.3%) were predicted to encode secretion or membraneproteins. In particular, 165(80.5%) of the 205 cDNAs selectedby PSORT were predicted to have signal sequences, while 70 (54.2%)of the 129 cDNAs selected by keyword trap preservedthe secretion or membrane protein-related keywords. Many importantcDNAs were obtained, including transporters, receptors, andligands, involved in significant cellular functions. Thus, anefficient method of selecting secretion or membrane protein-encodingcDNAs was developed by combining the above four procedures. 相似文献
237.
Ayumi Katayama Tomonori Kume Hikaru Komatsu Taku M. Saitoh Mizue Ohashi Michiko Nakagawa Masakazu Suzuki Kyoichi Otsuki Tomo’omi Kumagai 《Journal of plant research》2013,126(4):505-515
To clarify characteristics of carbon (C) allocation in a Bornean tropical rainforest without dry seasons, gross primary production (GPP) and C allocation, i.e., above-ground net primary production (ANPP), aboveground plant respiration (APR), and total below-ground carbon flux (TBCF) for the forest were examined and compared with those from Amazonian tropical rainforests with dry seasons. GPP (30.61 MgC ha?1 year?1, eddy covariance measurements; 34.40 MgC ha?1 year?1, biometric measurements) was comparable to those for Amazonian rainforests. ANPP (6.76 MgC ha?1 year?1) was comparable to, and APR (8.01 MgC ha?1 year?1) was slightly lower than, their respective values for Amazonian rainforests, even though aboveground biomass was greater at our site. TBCF (19.63 MgC ha?1 year?1) was higher than those for Amazonian forests. The comparable ANPP and higher TBCF were unexpected, since higher water availability would suggest less fine root competition for water, giving higher ANPP and lower TBCF to GPP. Low nutrient availability may explain the comparable ANPP and higher TBCF. These data show that there are variations in C allocation patterns among mature tropical rainforests, and the variations cannot be explained solely by differences in soil water availability. 相似文献
238.
Satsuki Otsuki Shinichi Nishimura Hisae Takabatake Kozue Nakajima Yasuaki Takasu Toru Yagura Yuki Sakai Akira Hattori Hideaki Kakeya 《Bioorganic & medicinal chemistry letters》2013,23(6):1608-1611
Irreversible modification is one of the most promising strategies to identify cellular receptors of bioactive small molecules. Here we report that receptor proteins can be chemically tagged using a 5-sulfonyl tetrazole probe. 5-Sulfonyl tetrazole easily accepted nucleophilic attack of thiol groups, while 5-sulfinyl tetrazole did not. These functional groups were introduced into probe molecules of a natural product. Cyclosporine A, an immunosuppressant produced by a microbe, was derivatized to possess 5-sulfonyl tetrazole and a tag group, which enabled chemical tagging of cyclophilin A, the cellular receptor of cyclosporine A. Cyclosporine A derivative possessing 5-sulfinyl tetrazole could not tag cyclophilin A. This technique will allow efficient identification of cellular receptors of bioactive small molecules. 相似文献
239.
Naoyoshi Kumakura Hiroka Otsuki Masayuki Tsuzuki Atsushi Takeda Yuichiro Watanabe 《PloS one》2013,8(11)
The RNA exosome is a multi-subunit complex that is responsible for 3ʹ to 5ʹ degradation and processing of cellular RNA. Rrp44/Dis3 is the catalytic center of the exosome in yeast and humans. However, the role of Rrp44/Dis3 homologs in plants is still unidentified. Here, we show that Arabidopsis AtRRP44A is the functional homolog of Rrp44/Dis3, is essential for plant viability and is required for RNA processing and degradation. We characterized AtRRP44A and AtRRP44B/SOV, two predicted Arabidopsis Rrp44/Dis3 homologs. AtRRP44A could functionally replace S. cerevisiae Rrp44/Dis3, but AtRRP44B/SOV could not. rrp44a knock-down mutants showed typical phenotypes of exosome function deficiency, 5.8S rRNA 3ʹ extension and rRNA maturation by-product over-accumulation, but rrp44b mutants did not. Conversely, AtRRP44B/SOV mutants showed elevated levels of a selected mRNA, on which rrp44a did not have detectable effects. Although T-DNA insertion mutants of AtRRP44B/SOV had no obvious phenotype, those of AtRRP44A showed defects in female gametophyte development and early embryogenesis. These results indicate that AtRRP44A and AtRRP44B/SOV have independent roles for RNA turnover in plants. 相似文献
240.
Sugawara J Komine H Hayashi K Yoshizawa M Otsuki T Shimojo N Miyauchi T Yokoi T Maeda S Tanaka H 《American journal of physiology. Heart and circulatory physiology》2007,293(3):H1466-H1472
Endurance training improves endothelium-dependent vasodilation, yet it does not increase basal blood flow in the legs. We determined the effects of a 3-mo aerobic exercise intervention on basal leg blood flow and alpha-adrenergic vasoconstriction and nitric oxide (NO) release in seven apparently healthy middle-aged and older adults (60 +/- 3 yr). Basal femoral artery blood flow (via Doppler ultrasound) (pretraining: 354 +/- 29; posttraining: 335 +/- 34 ml/min) and vascular conductance did not change significantly with the exercise training. Before the exercise intervention, femoral artery blood flow increased 32 +/- 16% with systemic alpha-adrenergic blockade (with phentolamine) (P < 0.05), and the addition of nitric oxide synthase (NOS) inhibition using N(G)-monomethyl-L-arginine (L-NMMA) did not affect femoral artery blood flow. After training was completed, femoral artery blood flow increased 47 +/- 7% with alpha-adrenergic blockade (P < 0.01) and then decreased 18 +/- 7% with the subsequent administration of L-NMMA (P < 0.05). Leg vascular conductance showed a greater alpha-adrenergic blockade-induced vasodilation (+1.7 +/- 0.5 to +3.0 +/- 0.5 units, P < 0.05) as well as NOS inhibition-induced vasoconstriction (-0.8 +/- 0.4 to -2.7 +/- 0.7 units, P < 0.05) after the exercise intervention. Resting plasma norepinephrine concentration significantly increased after the training. These results suggest that regular aerobic exercise training enhances NO bioavailability in middle-aged and older adults and that basal limb blood flow does not change with exercise training because of the contrasting influences of sympathetic nervous system activity and endothelium-derived vasodilation on the vasculature. 相似文献