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51.
Akiko Yano Satoru Horiya Takako Minami Eri Haneda Makiko Ikeda Kazuo Harada 《Nucleic acids research》2010,38(10):3489-3501
Many well-characterized examples of antisense RNAs from prokaryotic systems involve hybridization of the looped regions of stem–loop RNAs, presumably due to the high thermodynamic stability of the resulting loop–loop and loop–linear interactions. In this study, the identification of RNA stem–loops that inhibit U1A protein binding to the hpII RNA through RNA–RNA interactions was attempted using a bacterial reporter system based on phage λ N-mediated antitermination. As a result, loop sequences possessing 7–8 base complementarity to the 5′ region of the boxA element important for functional antitermination complex formation, but not the U1 hpII loop, were identified. In vitro and in vivo mutational analysis strongly suggested that the selected loop sequences were binding to the boxA region, and that the structure of the antisense stem–loop was important for optimal inhibitory activity. Next, in an attempt to demonstrate the ability to inhibit the interaction between the U1A protein and the hpII RNA, the rational design of an RNA stem–loop that inhibits U1A-binding to a modified hpII was carried out. Moderate inhibitory activity was observed, showing that it is possible to design and select antisense RNA stem–loops that disrupt various types of RNA–protein interactions. 相似文献
52.
Kensuke Miyamoto Toshihisa Kotake Makiko Sasamoto Marian Saniewski Junichi Ueda 《Journal of plant research》2010,123(3):363-370
The purpose of this study was to investigate the hormonal regulation of gummosis in grape hyacinth (Muscari armeniacum) bulbs, focusing especially on the chemical composition of the gums. The application of ethephon (2-chloroethylphosphonic
acid), an ethylene-releasing compound, at 1% and 2% (w/w) in lanolin as well as ethylene induced gummosis in the bulbs within
several days. Methyl jasmonate (JA-Me, 0.1–2% in lanolin) alone had no effect on gummosis. However, simultaneous application
of JA-Me and ethephon led to extreme stimulation of ethephon-induced gummosis. Ethephon-induced gummosis in the bulbs depended
on the maturation stage of the bulbs, increasing from April to July, but decreasing from August to September. Regardless of
the presence of JA-Me, the application of ethephon to the inflorescence axis of grape hyacinths did not induce gummosis. Gel
permeation chromatography analysis revealed that gums were homogenous polysaccharides with an average molecular mass of ca.
8.3 kDa. Analysis of the sugar composition of the gums after hydrolysis revealed that the molar ratio of Rha:Ara:Gal:GalA:GlcA
was 25:10:40:7:15. These results suggest that principal factors of gummosis as well as the chemical composition of gums differ
between species of bulbous plants. 相似文献
53.
Shohei Shinozaki Yoko Inoue Makiko Fukaya Edward A. Carter Young Ming-Yu Alan Fischman Ronald Tompkins Masao Kaneki 《Biochemical and biophysical research communications》2010,391(3):1459-710
Endotoxemia plays an important role in the pathogenesis of sepsis and is accompanied by dysregulated apoptosis of immune and non-immune cells. Treatment with statins reduces mortality in rodent models of sepsis and endotoxemia. Inhibition of protein isoprenylation, including farnesylation, has been proposed as a mechanism to mediate the lipid-lowering-independent effects of statins. Nonetheless, the effects of the inhibition of isoprenylation have not yet been studied. To investigate the role of farnesylation, we evaluated the effects of farnesyltransferase inhibitor and statin on survival following lipopolysaccharide (LPS) challenge in mice. Both simvastatin (2 mg/kg BW) and FTI-277 (20 mg/kg BW) treatment improved survival by twofold after LPS injection, as compared with vehicle alone (p < 0.01). LPS-induced cleavage (activation) of caspase-3, an indicator of apoptotic change, and increased protein expression of proapoptotic molecules, Bax and Bim, and activation of c-Jun NH2-terminal kinase (JNK/SAPK) in the liver and spleen were attenuated by both simvastatin and FTI-277. These results demonstrate that farnesyltransferase inhibitor as well as statin significantly reduced LPS-induced mortality in mice. Our findings also suggest that inhibition of protein farnesylation may contribute to the lipid-lowering-independent protective effects of statins in endotoxemia, and that protein farnesylation may play a role in LPS-induced stress response, including JNK/SAPK activation, and apoptotic change. Our data argue that farnesyltransferase may be a potential molecular target for treating patients with endotoxemia. 相似文献
54.
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56.
Control of cocklebur seed germination by nitrogenous compounds : Nitrite, nitrate, hydroxylamine, thiourea, azide and cyanide 总被引:3,自引:0,他引:3
Esashi Yohji; Ohhara Yuuko; Okazaki Makiko; Hishinuma Kohya 《Plant & cell physiology》1979,20(2):349-361
Germination of non-dormant upper cocklebur (Xanthium pinsylvanicumWallr.) seeds was stimulated by not only CS(NH2)2 but also NH2OH,KCN and NaN3. This stimulation was not via the enhancement ofaerobic C2H4 production. NH2OH, KCN and NaN3 in certain concentrationspromoted the initial growth of axial and/or cotyledonary parts,but the degree of growth promotion by NH2OH, NaN3 and KCN wasslight compared with that by CS(NH2)2. As in the case of CS(NH2)2,however, the germinationstimulating effect of NH2OH disappearedrapidly as the preceding imbibition period was prolonged. Incontrast, KCN and NaN3 were still effective in stimulating thegermination of aged seeds maintained on a water substratum,as previously seen with anaerobiosis. Anaerobic induction wasenhanced not only by NaN3 and KCN but also by NH2OH, KNO3, KNO2CO(NH2)2 and CS(NH2)2 applied during the anaerobic treatment,but without causing an increase in anaerobic production of C2H4.Furthermore, KCN and NaN3, given prior to the anaerobic treatmentacted additively with anaerobic induction. The germination-stimulatingactions of nitrogenous compounds are discussed in comparisonwith those of C2H4 and anaerobiosis. (Received May 6, 1978; ) 相似文献
57.
Yoshiro Naito Hisashi Sawada Makiko Oboshi Aya Fujii Shinichi Hirotani Toshihiro Iwasaku Yoshitaka Okuhara Akiyo Eguchi Daisuke Morisawa Mitsumasa Ohyanagi Takeshi Tsujino Tohru Masuyama 《PloS one》2013,8(10)
Although iron is reported to be associated with the pathogenesis of chronic kidney disease, it is unknown whether iron participates in the pathophysiology of nephrosclerosis. Here, we investigate whether iron is involved in the development of hypertensive nephropathy and the effects of iron restriction on nephrosclerosis in salt- loaded stroke-prone spontaneously hypertensive rats (SHRSP). SHRSP were given either a normal or high-salt diet for 8 weeks. Another subset of SHRSP were fed a high-salt with iron-restricted diet. SHRSP given a high-salt diet developed severe hypertension and nephrosclerosis. As a result, survival rate was decreased after 8 weeks diet. Importantly, massive iron accumulation and increased iron content were observed in the kidneys of salt-loaded SHRSP, along with increased superoxide production, urinary 8-Hydroxy-2′-deoxyguanosine excretion, and urinary iron excretion; however, these changes were markedly attenuated by iron restriction. Of interest, expression of cellular iron transport proteins, transferrin receptor 1 and divalent metal transporter 1, was increased in the tubules of salt-loaded SHRSP. Notably, iron restriction attenuated the development of severe hypertension and nephrosclerosis, thereby improving survival rate in salt-loaded SHRSP. Taken together, these results suggest a novel mechanism by which iron plays a role in the development of hypertensive nephropathy and establish the effects of iron restriction on salt-induced nephrosclerosis. 相似文献
58.
Nagahama T Hamamoto M Nakase T Shimamura S Horikoshi K 《The Journal of General and Applied Microbiology》2006,52(1):37-45
Phylogenetic relationships within the Erythrobasidium clade as a lineage of the urediniomycetous yeasts were examined using partial regions of 18S rDNA, 5.8S rDNA, 26S rDNA, internal transcribed spacers (ITSs), and elongation factor (EF)-1alpha. Combined data analysis of all segments successfully yielded a reliable phylogeny and confirmed the cohesion of species characterized by Q-10(H2) as a major ubiquinone. Differences in secondary structure predicted for a variable region in 26S rDNA corresponded to major divergences in the phylogenetic tree based on the primary sequence. The common presence of a shortened helix in this region was considered to be evidence of monophyly for species with Q-10(H2), Sakaguchia dacryoides, Rhodotorula lactosa, and Rhodotorula lamellibrachiae, although it was not as strongly supported by the combined data tree. The information on intron positions in the EF-1alpha gene had potential usefulness in the phylogenetic inference between closely related species. 相似文献
59.
Yoshifumi Matsumoto Chihiro Hiramatsu Yuka Matsushita Norihiro Ozawa Ryuichi Ashino Makiko Nakata Satoshi Kasagi Anthony Di Fiore Colleen M. Schaffner Filippo Aureli Amanda D. Melin Shoji Kawamura 《Molecular ecology》2014,23(7):1799-1812
New World monkeys exhibit prominent colour vision variation due to allelic polymorphism of the long‐to‐middle wavelength (L/M) opsin gene. The known spectral variation of L/M opsins in primates is broadly determined by amino acid composition at three sites: 180, 277 and 285 (the ‘three‐sites’ rule). However, two L/M opsin alleles found in the black‐handed spider monkeys (Ateles geoffroyi) are known exceptions, presumably due to novel mutations. The spectral separation of the two L/M photopigments is 1.5 times greater than expected based on the ‘three‐sites’ rule. Yet the consequence of this for the visual ecology of the species is unknown, as is the evolutionary mechanism by which spectral shift was achieved. In this study, we first examine L/M opsins of two other Atelinae species, the long‐haired spider monkeys (A. belzebuth) and the common woolly monkeys (Lagothrix lagotricha). By a series of site‐directed mutagenesis, we show that a mutation Y213D (tyrosine to aspartic acid at site 213) in the ancestral opsin of the two alleles enabled N294K, which occurred in one allele of the ateline ancestor and increased the spectral separation between the two alleles. Second, by modelling the chromaticity of dietary fruits and background leaves in a natural habitat of spider monkeys, we demonstrate that chromatic discrimination of fruit from leaves is significantly enhanced by these mutations. This evolutionary renovation of L/M opsin polymorphism in atelines illustrates a previously unappreciated dynamism of opsin genes in shaping primate colour vision. 相似文献
60.