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2.
Molecular and Biochemical Characterization of Three Anthocyanin Synthetic Enzymes from Gentiana triflora 总被引:5,自引:0,他引:5
Tanaka Yoshikazu; Yonekura Keiko; Fukuchi-Mizutani Masako; Fukui Yuko; Fujiwara Hiroyuki; Ashikari Toshihiko; Kusumi Takaaki 《Plant & cell physiology》1996,37(5):711-716
Full length cDNA clones of flavonoid 3',5'-hydroxylase, dihydroflavonol4-reductase and flavonoid 3-glucosyltransferase were clonedfrom petals of Gentiana triflora. Their sequences were homologousto counterparts from other plants. Flavonoid 3',5'-hydroxylaseand flavonoid 3-glucosyltransferase were enzymatically characterizedby expressing cDNAs in heterologous expression systems. (Received May 21, 1996; Accepted June 4, 1996) 相似文献
3.
Shawnna M. Buttery Keiko Kono Ema Stokasimov David Pellman 《Molecular biology of the cell》2012,23(20):4041-4053
Formin-family proteins promote the assembly of linear actin filaments and are required to generate cellular actin structures, such as actin stress fibers and the cytokinetic actomyosin contractile ring. Many formin proteins are regulated by an autoinhibition mechanism involving intramolecular binding of a Diaphanous inhibitory domain and a Diaphanous autoregulatory domain. However, the activation mechanism for these Diaphanous-related formins (DRFs) is not completely understood. Although small GTPases play an important role in relieving autoinhibition, other factors likely contribute. Here we describe a requirement for the septin Shs1 and the septin-associated kinase Gin4 for the localization and in vivo activity of the budding yeast DRF Bnr1. In budding yeast strains in which the other formin, Bni1, is conditionally inactivated, the loss of Gin4 or Shs1 results in the loss of actin cables and cell death, similar to the loss of Bnr1. The defects in these strains can be suppressed by constitutive activation of Bnr1. Gin4 is involved in both the localization and activation of Bnr1, whereas the septin Shs1 is required for Bnr1 activation but not its localization. Gin4 promotes the activity of Bnr1 independently of the Gin4 kinase activity, and Gin4 lacking its kinase domain binds to the critical localization region of Bnr1. These data reveal novel regulatory links between the actin and septin cytoskeletons. 相似文献
4.
Wakae Fujimaki Keiko Baba Katsunori Tatara Ryohji Umezu Sanji Kusakawa Yasushige Mashima 《Human genetics》1987,76(3):302-302
Summary A case of ring chromosome 15 passed on to the index patient's two children is reported, and possible reasons for the infrequent records of inheritance of ring chromosome are suggested. 相似文献
5.
Yutaro Yamagata Yukiko Muramoto Sho Miyamoto Keiko Shindo Masahiro Nakano Takeshi Noda 《Microbiology and immunology》2019,63(5):164-171
Defective interfering (DI) influenza viruses carry a large deletion in a gene segment that interferes with the replication of infectious virus; thus, such viruses have potential for antiviral therapy. However, because DI viruses cannot replicate autonomously without the aid of an infectious helper virus, clonal DI virus stocks that are not contaminated with helper virus have not yet been generated. To overcome this problem, we used reverse genetics to generate a clonal DI virus with a PB2 DI gene, amplified the clonal DI virus using a cell line stably expressing the PB2 protein, and confirmed its ability to interfere with infectious virus replication in vitro. Thus, our approach is suitable for obtaining purely clonal DI viruses, will contribute to the understanding of DI virus interference mechanisms and can be used to develop DI virus‐based antivirals. 相似文献
6.
Guanethidine treatment or adrenal medullectomy significantly inhibited the elevation in blood pressure induced by Clostridium perfringens beta toxin, and the combination of the two drastically reduced the pressure rise, to less than 19% of that in control rats. When rats were pretreated with tetrodotoxin or hexamethonium, the toxin-evoked rise was significantly inhibited. Elevation in blood pressure induced by the toxin in spinal rats tended to be less than that in control rats. When investigated by a microscopical technique, arteriolar constriction in the mesenteric vasculature was observed after the blood pressure elevation induced by the toxin reached a maximum. Blood flow in the skin decreased with an increase in blood pressure following intravenous injection of the toxin. It is concluded that beta toxin acts on the autonomic nervous system and produces arterial constriction. 相似文献
7.
Tomonori Ueno Keisuke Tanaka Keiko Kaneko Yuki Taga Tetsutaro Sata Shinkichi Irie Shunji Hattori Kiyoko Ogawa-Goto 《The Journal of biological chemistry》2010,285(39):29941-29950
A coiled-coil microtubule-bundling protein, p180, was originally reported as a ribosome-binding protein on the rough endoplasmic reticulum (ER) and is highly expressed in secretory tissues. Recently, we reported a novel role for p180 in the trans-Golgi network (TGN) expansion following stimulated collagen secretion. Here, we show that p180 plays a key role in procollagen biosynthesis and secretion in diploid fibroblasts. Depletion of p180 caused marked reductions of secreted collagens without significant loss of the ER membrane or mRNA. Metabolic labeling experiments revealed that the procollagen biosynthetic activity was markedly affected following p180 depletion. Moreover, loss of p180 perturbs ascorbate-stimulated de novo biosynthesis mainly in the membrane fraction with a preferential secretion defect of large proteins. At the EM level, one of the most prominent morphological features of p180-depleted cells was insufficient ribosome association on the ER membranes. In contrast, the ER of control cells was studded with numerous ribosomes, which were further enhanced by ascorbate. Similarly biochemical analysis confirmed that levels of membrane-bound ribosomes were altered in a p180-dependent manner. Taken together, our data suggest that p180 plays crucial roles in enhancing collagen biosynthesis at the entry site of the secretory compartments by a novel mechanism that mainly involves facilitating ribosome association on the ER. 相似文献
8.
9.
Sakayu Shimizu Keiko Inoue Yoshiki Tani Hideaki Yamada 《Biochemical and biophysical research communications》1981,103(4):1231-1237
The preparation of highly purified medium chain acyl-CoA synthetase (Acid: CoA ligase, AMP-forming (EC 6.2.1.2)) from the cell extracts of is described. The enzyme is inducibly formed in the cells of the microorganism, when it is grown with butyrate as a major carbon source. The purified enzyme is homogeneous on disc gel electrophoresis. Its molecular weight is approximately 142,000, and it is possibly composed of 4 identical subunits of approximately 37,000 molecular weight and has isoelectric point of 4.3. The enzyme catalyzes the stoichiometric conversion of butyrate and CoA to butyryl-CoA in the presence of ATP and Mg2+. It also activates fatty acids with carbon chain lengths of 3 to 5 well, but is inactive toward fatty acids with carbon chain lengths of more than 6. The enzyme is sulfhydryl dependent and inactivated by silver and mercury compounds. 相似文献
10.
Plants develop unorganized cell masses like callus and tumors in response to various biotic and abiotic stimuli. Since the historical discovery that the combination of two growth-promoting hormones, auxin and cytokinin, induces callus from plant explants in vitro, this experimental system has been used extensively in both basic research and horticultural applications. The molecular basis of callus formation has long been obscure, but we are finally beginning to understand how unscheduled cell proliferation is suppressed during normal plant development and how genetic and environmental cues override these repressions to induce callus formation. In this review, we will first provide a brief overview of callus development in nature and in vitro and then describe our current knowledge of genetic and epigenetic mechanisms underlying callus formation. 相似文献