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961.
Asako Kaise Kiminori Ohta Shinya Fujii Akifumi Oda Tokuhito Goto Yasuyuki Endo 《Bioorganic & medicinal chemistry》2018,26(13):3805-3811
Based on the co-crystal structure of bicalutamide with a T877A-mutated androgen receptor (AR), glycerol and aminoglycerol derivatives were designed and synthesized as a novel type of carborane-containing AR modulators. The (R)-isomer of 6c, whose chirality is derived from the glycerol group, showed 20 times more potent cell inhibitory activity against LNCaP cell lines expressing T877A-mutated AR than the corresponding (S)-isomer. Docking studies of both isomers with AR suggested that (R)-6c is in closer spatial proximity to helix-12 of the AR than (S)-6c, which is the most important common motif in the secondary structure of AR for the expression of antagonistic activity. 相似文献
962.
963.
Hideyuki Matsushima Shun Shimohama Motohiko Chachin Takashi Taniguchi Jun Kimura 《Journal of neurochemistry》1996,67(1):317-323
Abstract: We examined protein kinase C (PKC) activity in Ca2+ -dependent PKC (Ca2+ -dependent PKC activities) and Ca2+ -independent PKC (Ca2+ -independent PKC activities) assay conditions in brains from Alzheimer's disease (AD) patients and age-matched controls. In cytosolic and membranous fractions, Ca2+ -dependent and Ca2+ -independent PKC activities were significantly lower in AD brain than in control brain. In particular, reduction of Ca2+ -independent PKC activity in the membranous fraction of AD brain was most enhanced when cardiolipin, the optimal stimulator of PKC-ε, was used in the assay; whereas Ca2+ -independent PKC activity stimulated by phosphatidylinositol, the optimal stimulator of PKC-δ, was not significantly reduced in AD. Further studies on the protein levels of Ca2+ -independent PKC-δ, PKC-ε, and PKC-ζ in AD brain revealed reduction of the PKC-ε level in both cytosolic and membranous fractions, although PKC-δ and PKC-ζ levels were not changed. These findings indicated that Ca2+ -dependent and Ca2+ -independent PKC are changed in AD, and that among Ca2+ -independent PKC isozymes, the alteration of PKC-ε is a specific event in AD brain, suggesting its crucial role in AD pathophysiology. 相似文献
964.
Kazuhiro Tashima Hideyuki Yamamoto Chiaki Setoyama Tsunehiko Ono Eishichi Miyamoto 《Journal of neurochemistry》1996,66(1):57-64
Abstract: To investigate the physiological role of Ca2+ /calmodulin-dependent protein kinase II (CaM kinase II) in neuronal differentiation, we transfected the cDNA of the α subunit of mouse CaM kinase II (CaM kinase IIα) into PC12 cells and established clonal cell lines that constitutively express the transfected CaM kinase IIα gene. The expression of CaM kinase IIα was confirmed by northern blot and immunoblot analyses. Northern blot analysis showed that the γ and δ subunits of CaM kinase II are mainly expressed in PC12 cells. Treatment of the cells with ionomycin activated CaM kinase IIα through autophosphorylation and generation of the Ca2+ /calmodulin-independent form. It is interesting that the neurite outgrowth induced by dibutyryl cyclic AMP was inhibited in these cell lines in accordance with the activities of overexpressed CaM kinase IIα. The activity of cyclic AMP-dependent protein kinase showed similar levels among these cell lines. These results suggest that CaM kinase II is involved in the modulation of the neurite outgrowth induced by activation of the cyclic AMP system. 相似文献
965.
Association between theRfp-Y haplotype and the incidence of Marek's disease in chickens 总被引:1,自引:1,他引:0
Patricia S. Wakenell Marcia M. Miller Ronald M. Goto W. James Gauderman W. Elwood Briles 《Immunogenetics》1996,44(4):242-245
Certain haplotypes at the major histocompatibility (B) complex (Mhc) of the chicken provide an easily demonstrated influence on tumor formation following infections with Marek’s disease virus
(MDV). Recognition that there is a second histocompatibility complex of genes in the chicken, Rfp-Y, comprised of Mhc class I and class II genes, some of which are at least transcribed, evokes the question of whether this gene complex might
also influence the outcome of MDV infections. To test this hypothesis, pedigree-hatched chicks in families from the original
Rfp-Y-defining stock in which three Rfp-Y and two B system haplotypes are segregating were challenged with the RB1B strain of MDV. Birds with the Y
3
/Y
3
genotype were found to have 2.3 times the risk of developing a tumor compared with birds with other Rfp-Y genotypes combined (P <0.02). Additionally, birds carrying the B
R9
/B
11
genotype had 2.3 times the risk of tumor formation, relative to birds with the B
11
/B
11
genotype (P <0.02). We found no evidence for an interaction between genotypes within the B and Rfp-Y systems. These data provide evidence that Rfp-Y haplotypes, as well as B haplotypes, can significantly influence the outcome of infection with MDV.
Received: 15 February 1996 / Revised: 23 April 1996 相似文献
966.
Isolation and characterization of cDNAs encoding vacuolar H+-pyrophosphatase isoforms from rice (Oryza sativa L.) 总被引:2,自引:0,他引:2
Yoshikiyo Sakakibara Hideyuki Kobayashi Kunihiro Kasamo 《Plant molecular biology》1996,31(5):1029-1038
The vacuolar H+-pyrophosphatase (V-PPase) is an electrogenic H+ pump, which was found in the plant vacuolar membrane. Two cDNA clones (OVP1 and OVP2) encoding the V-PPase were isolated from cultured rice (Oryza sativa L.) cells and subsequently sequenced. The sequence analysis has revealed thatOVP1 contains 2316 nucleotides of open reading frame (ORF) and 362 nucleotides of the 3-untranslated region, whereasOVP2 comprises 2304 nucleotides of ORF and 312 nucleotides of the 3-untranslated region. The nucleotide sequences of ORF ofOVP1 andOVP2 are 80.7% identical, and their 5- and 3-untranslated regions have 39.4% and 48.4% identity, respectively. The polypeptides encoded by the ORF ofOVP1 andOVP2 contain 771 and 767 amino acids, respectively, and the sequences of the OVP proteins are very similar to those of other V-PPases, which are shown to have 85–91% homology. Chromosomal mapping by RFLP techniques demonstrates that OVP1 and OVP2 are isoforms encoded by different genes. BothOVP1 andOVP2 are mapped on the same chromosome (chromosome 6) to a distance of ca. 90 cM. Northern analysis indicates that theOVP1 andOVP2 are also expressed in intact rice plants andOVP2 shows higher expression in the calli than the roots and shoots, compared toOVP1. These results show that at least two genes encoding the V-PPases are present in rice genome and their expressions are probably regulated in a different manner. 相似文献
967.
Shun Shimohama Sadaki Fujimoto Hideyuki Matsushima †Tadafumi Takenawa ‡Takashi Taniguchi §George Perry Peter J. Whitehouse Jun Kimura 《Journal of neurochemistry》1995,64(6):2629-2634
Abstract: Phosphoinositide-specific phospholipase C (PLC) is a key enzyme in signal transduction. We have previously demonstrated that an antibody to an isozyme of PLC, PLC-δ, produced intense staining of neurofibrillary tangles in the brains of patients with Alzheimer's disease. In the present study, we investigated the protein level and activity of this enzyme in control and Alzheimer brains. Western blot analysis using a specific antibody for PLC-δ showed that the concentration of PLC-δ protein was significantly higher in the cytosolic fraction of Alzheimer's disease cortical tissue than in control brains. The activity of PLC-δ, which hydrolyzes phosphatidylinositol, was also investigated, and we found that PLC-δ activity was not significantly different in the Alzheimer and control cytosolic fractions. These results indicate that the specific activity of PLC-δ is decreased in Alzheimer brains and suggest that inactivation of PLC-δ might be related to the pathophysiology of this disease. 相似文献
968.
Yuhashi Ken-Ichi; Akao Shoichiro; Fukuhara Hideyuki; Tateno Eiji; Chun Jong-Yoon; Stacey Gary; Hara Hiromichi; Kubota Masatsugu; Asami Teruo; Minamisawa Kiwamu 《Plant & cell physiology》1995,36(8):1571-1577
When soybean roots were inoculated with Bradyrhizobium elkaniiUSDA76, USDA94 or USDA31, a localized swelling of the root outercortical cells was observed within 10 days after inoculation.This phenotype was designated outer cortical swelling (OCS).OCS was not observed in roots inoculated with B.japonicum USDA110or USDA122. Therefore, the OCS response appears to be specificfor B. elkanii. To determine the involvement of the nodulationgenes in OCS formation, we constructed a nod- mutant, strainUSDA94 相似文献
969.
Hiroshi Yamamoto Toshiaki Endo Tamotsu Kiya Taeko Goto Satoru Sagae Eiki Ito Hiroshi Watanabe Ryuichi Kudo 《Prostaglandins & other lipid mediators》1995,50(4)
In rat luteal cells labeled with (3H]oleic acid, PGF2α-stimulated phospholipase D (PLD) activation was investigated. The PLD activity was detected by measuring the accumulation of [3H]phosphatidylethanol (PtdEt) in the presence of ethanol. PGF2α stimulated PtdEt accumulation at concentrations of more than 100 nM in the presence of ethanol. However, PtdEt accumulation did not change in the absence of ethanol. PGF2α (1 μM) increased PtdEt accumulation after 1 min, and the accumulation reached a plateau by 2–3 min. These results indicate that PGF2α activates PLD in rat luteal cells. U-73122, a phospholipase C (PLC) inhibitor, and staurosporine, a protein kinase C (PKC) inhibitor, did not inhibit PGF2α-stimulated [3H]PtdEt accumulation. These results suggest that PGF2α-induced PLD activation is different from PLC-PKC systems. We reported previously that PGF2α stimulated the release of arachidonic acid. The effects of indomethacin, nordihydroguaiaretic acid (NDGA), and 5,8,11,14-eicosatetraynoic acid (ETYA), inhibitors of arachidonic acid metabolism, on PGF2α-stimulated PtdEt accumulation were examined. Pretreatment with indomethacin enhanced PGF2α-induced PtdEt accumulation. In contrast, pretreatment with NDGA and ETYA inhibited PGF2α-induced PtdEt accumulation. It is suggested that PGF2α-stimulated PLD activation is mediated via lipoxygenase products. 相似文献
970.
Matsuhashi M Endoh K Pankrushina AN Watanabe H Yamamura H Komiyama M Endo S Tobi M Ohshima H Mano Y Hyodo M Kaneko T Otani S 《The Journal of General and Applied Microbiology》1997,43(4):225-230
Carbon material such as graphite and activated charcoal, but not diamond, causes the promotion of growth of certain bacteria under ordinarily non-permissive stress conditions over a distance of several centimeters. Bacillus carboniphilus under the stress of a high KCl concentration and high temperature responded to this remote effect of carbon material with enhanced growth, and thermophile bacterium Bacillus stearothermophilus responded similarly yet moderately under the stress of low temperature. The remote effect of carbon was caused by its activation with external energy, probably of electromagnetic nature, as this effect was markedly decreased by sheltering the experimental system with an iron or aluminum barrier. Carbon material probably transforms the external oscillatory pulses or radiation into a signal exerting, far-reaching, growth-promoting effect upon cells. The most plausible candidate of signals emitted from carbon was considered to be (ultra)sonic. 相似文献