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971.
Okumura-Noji K Sasai K Zhan R Kawaguchi H Maruyama H Tada T Takahashi H Okazaki M Miida T Sakuma N Kimura G Ohta N Yokoyama S 《Biochemical and biophysical research communications》2001,281(2):305-310
It was investigated whether proteasome activity was implicated in susceptibility of human vascular smooth muscle cells (VSMCs) to Fas-mediated death. Human fetal aorta smooth muscle cells were treated with agonistic anti-Fas antibody (CH11) and proteasome inhibitors (MG115 or MG132) and then cell death was determined by morphology, viability, and DNA fragmentation. The present study reports that: (a) crosslinking of Fas receptor with anti-Fas antibody in the presence of proteasome inhibitor-induced death and DNA degradation in human VSMCs that were blocked by caspases inhibitor z-DEVD.fmk; (b) cotreatment with anti-Fas antibody and proteasome inhibitor activated caspase-3; (c) proteasome inhibitors did not influence expression of procaspase-8, procaspase-3, c-FLIP, and Bcl-2; and (d) proteasome inhibitors up-regulated Fas and FADD. The data indicate that proteasome activity is important in survival of VSMCs and provide the first evidence that proteasome is involved in Fas signal transduction. The present study proposes novel mechanism(s) by which VSMCs become susceptible to FasL. 相似文献
972.
Serotonin and dopamine are involved in the attachment and metamorphosis of cypris larvae of barnacles. Aromatic L-amino acid decarboxylase (AADC) gene, the product of which catalyzes the synthesis of serotonin and dopamine from L-5-hydroxytryptophan and L-3,4-dihydroxyphenylalanine, respectively, was characterized. A DNA clone containing part of an AADC sequence was obtained from the genomic DNA library of the barnacle, Balanus amphitrite. This clone had four putative exons consisting of 226 amino acids with an identity of 63.2% and a similarity of 92.1% with human AADC. Northern blot analysis showed that AADC mRNA was expressed at all stages of barnacles: naupliar larvae, cypris larvae and adult barnacles. Two inducers of larval attachment and metamorphosis; that is, serotonin and extract of adult barnacles, obviously increased the expression of AADC mRNA at an early cypris larval stage. These results suggest that intracellular biosynthesis of serotonin, or dopamine, or both is at least partly involved in the control of the attachment and metamorphosis of cypris larvae. 相似文献
973.
Lipase-catalyzed optical resolution of (+/-)-epoxy-beta-cyclogeraniol (1), a key synthetic intermediate for epoxy-beta-ionylideneacetic acid, was achieved in high enantiomeric purity. Transesterification with vinyl acetate by using lipase P (Nagase) made enriched (-)-1, while hydrolysis of the corresponding acetate by using lipase P (Amano) afforded (+)-1 with a high E value (E = 1600). 相似文献
974.
Hiroyuki Mitono Hiroshi Endoh Kazunobu Okazaki Takashi Ichinose Shizue Masuki Akira Takamata Hiroshi Nose 《Journal of applied physiology》2005,99(3):902-908
We examined the hypothesis that elevation of the body core temperature threshold for forearm skin vasodilation (TH(FVC)) with increased exercise intensity is partially caused by concomitantly increased plasma osmolality (P(osmol)). Eight young male subjects, wearing a body suit perfused with warm water to maintain the mean skin temperature at 34 +/- 1 degree C (ranges), performed 20-min cycle-ergometer exercise at 30% peak aerobic power (VO2(peak)) under isoosmotic conditions (C), and at 65% VO2(peak) under isoosmotic (H(EX)I(OS)) and hypoosmotic (H(EX)L(OS)) conditions. In H(EX)L(OS), hypoosmolality was attained by hypotonic saline infusion with DDAVP, a V2 agonist, before exercise. P(osmol) (mosmol/kg H2O) increased after the start of exercise in both H(EX) trials (P < 0.01) but not in C. The average P(osmol) at 5 and 10 min in H(EX)I(OS) was higher than in C (P < 0.01), whereas that in H(EX)L(OS) was lower than in H(EX)I(OS) (P < 0.01). The change in TH(FVC) was proportional to that in P(osmol) in every subject for three trials. The change in TH(FVC) per unit change in P(osmol) (deltaTH(FVC)/deltaP(osmol), degrees C x mosmol(-1) x kg H2O(-1)) was 0.064 +/- 0.012 when exercise intensity increased from C to H(EX)I(OS), similar to 0.086 +/- 0.020 when P(osmol) decreased from H(EX)I(OS) to H(EX)L(OS) (P > 0.1). Moreover, there were no significant differences in plasma volume, heart rate, mean arterial pressure, and plasma lactate concentration around TH(FVC) between H(EX)I(OS) and H(EX)L(OS) (P > 0.1). Thus the increase in TH(FVC) due to increased exercise intensity was at least partially explained by the concomitantly increased P(osmol). 相似文献
975.
Synthesis of Lanostane‐Type Triterpenoid N‐Glycosides and Their Cytotoxicity against Human Cancer Cell Lines
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Motohiko Ukiya Teppei Hayakawa Kouta Okazaki Maiko Hikawa Hiroyuki Akazawa Wei Li Kazuo Koike Makoto Fukatsu 《化学与生物多样性》2018,15(7)
Seventeen lanostane‐type triterpenoid derivatives ( 2 – 18 ), including 11N‐glycosides ( 8 – 18 ), were synthesized from the natural triterpenoid, lanosterol ( 1 ), and were evaluated for their cytotoxicity against the human cancer cell lines, HL‐60, A549, and MKN45, as well as the normal human lung cells, WI‐38. Among them, N‐β‐d ‐2‐acetamido‐2‐deoxyglucoside ( 10 ) showed cytotoxicity against HL‐60, A549, MKN45, and WI‐38 cells (IC50 0.0078 – 2.8 μm ). However, N‐β‐d ‐galactoside ( 12 ) showed cytotoxicity against HL‐60 and MKN45 cells (IC50 0.0021 – 4.0 μm ), but not the normal WI‐38 cells. Furthermore, Western blot analysis suggested that 12 induces apoptosis by activation of caspases‐3, 8, and 9. These results will be useful for the synthesis of other tetracyclic triterpenoids or steroid N‐glycosides to increase their cytotoxicity and apoptosis‐inducing activities. 相似文献
976.
Honoka Okazaki Yuka Ohori Masaya Komoto Young-Ho Lee Yuji Goto Naoya Tochio Chiaki Nishimura 《FEBS letters》2013
Alpha-synuclein is analyzed in physiological conditions by CLEANEX-PM methodology, in which the amide-proton exchange can be monitored at millisecond scale. The relationship between kex and [OH]− is confirmed as a linear correlation with slope 1, indicating EX2 regime. There are significant residual structures at the N- and C-terminal regions. The structure at the C-terminal region is more stable than that of the N-terminal region. The middle part including NAC region is not completely protected. The data acquired at various pH and mixing time conditions followed by linear fitting give accurate information about residual structures. 相似文献
977.
978.
Takao Arimori Noriko Kawamoto Shoko Shinya Nobuo Okazaki Masami Nakazawa Kazutaka Miyatake Tamo Fukamizo Mitsuhiro Ueda Taro Tamada 《The Journal of biological chemistry》2013,288(26):18696-18706
Chitinase C from Ralstonia sp. A-471 (Ra-ChiC) has a catalytic domain sequence similar to goose-type (G-type) lysozymes and, unlike other chitinases, belongs to glycohydrolase (GH) family 23. Using NMR spectroscopy, however, Ra-ChiC was found to interact only with the chitin dimer but not with the peptidoglycan fragment. Here we report the crystal structures of wild-type, E141Q, and E162Q of the catalytic domain of Ra-ChiC with or without chitin oligosaccharides. Ra-ChiC has a substrate-binding site including a tunnel-shaped cavity, which determines the substrate specificity. Mutation analyses based on this structural information indicated that a highly conserved Glu-141 acts as a catalytic acid, and that Asp-226 located at the roof of the tunnel activates a water molecule as a catalytic base. The unique arrangement of the catalytic residues makes a clear contrast to the other GH23 members and also to inverting GH19 chitinases. 相似文献
979.
Hiroya Tomita Motoki Shimizu Md. Asad-ud Doullah Ryo Fujimoto Keiichi Okazaki 《Molecular breeding : new strategies in plant improvement》2013,32(4):889-900
Throughout the world, clubroot disease is one of the most damaging diseases affecting Brassica oleracea. To develop marker-assisted selection (MAS) that could assist the incorporation of durable clubroot resistance (CR) into cultivars, previous genetic analyses have identified several CR quantitative trait loci (CR–QTL). However, the independent and cumulative effects of each CR locus against various isolates have rarely been tested. Previously, we identified one major CR–QTL and four minor CR–QTL in the F2 plants from broccoli doubled haploid (DH) line × cabbage DH line of B. oleracea. In the present study, to clarify their effectiveness for controlling disease involving various isolates, inoculation testing was conducted in genotypes with various combinations of the CR genes, which were selected using the DNA markers closely associated with each CR–QTL. In exploring the overall disease incidence, it was apparent that a single involvement of the major CR gene located in the PbBo(Anju)1 locus, or accumulation of CR genes in the minor CR–QTL, is not enough to confer sufficient resistance. One major CR gene in the QTL PbBo(Anju)1 locus plus two to three minor CR genes conferred moderate resistance. The genotype in which all of the CR genes locating in the five QTL including PbBo(Anju)1 were accumulated showed the highest resistance, and it was broadly resistant against six isolates. Accumulation of several CR genes by MAS is necessary to conduct CR breeding in B. oleracea. Our developed DNA markers can be used efficiently to make selections of required loci for the acquisition of resistance, and use of these markers will be a powerful tool for CR breeding in B. oleracea. 相似文献
980.
Ayako Masuda Hidekata Yasuoka Takashi Satoh Yuka Okazaki Yukie Yamaguchi Masataka Kuwana 《Arthritis research & therapy》2013,15(4):R74