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11.
Pattaporn Jaikhan Benjaporn Buranrat Yukihiro Itoh Jiranan Chotitumnavee Takashi Kurohara Takayoshi Suzuki 《Bioorganic & medicinal chemistry letters》2019,29(10):1173-1176
Fe(II)/α-ketoglutarate-dependent lysine demethylases (KDMs) are attractive drug targets for several diseases including cancer. In this study, we designed and screened ortho-substituted anilides that are expected to function as Fe(II) chelators, and identified ortho-hydroxy anilide as a novel scaffold for KDM5A inhibitors. Treatment of human lung cancer A549 cells with a prodrug form of 4-carboxy-2-hydroxy-formanilide (9c) increased trimethylated lysine 4 on histone H3 level, suggesting KDM5 inhibition in the cells. 相似文献
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An increasing attention has been dedicated to the characterization of complex networks within the protein world. Before now most investigations about protein structures were only considered where the interactive cutoff distance Rc=5 or 7 Å. It is noteworthy that the length of peptide bond is about 1.5 Å, the length of hydrogen bond is about 3 Å, the range of London-van der Waals force is about 5 Å and the range of hydrophobic effect can reach to 12 Å in protein molecule. Present work reports a study on the topological properties of the amino acid network constructed by different interactions above. The results indicate that the small-world property of amino acid network constructed by the peptide and hydrogen bond, London-van der Waals force and the hydrophobic effect is strong, very strong and relatively weak, respectively. Besides, there exists a precise exponential relation C∝k−0.5 at Rc=12 Å. It means that the amino acid network constructed by the hydrophobic effect tend to be hierarchical. Functional modules could be the cause for hierarchical modularity architecture in protein structures. This study on amino acid interactive network for different interactions facilitates the identification of binding sites which is strongly linked with protein function, and furthermore provides reasonable understanding of the underlying laws of evolution in genomics and proteomics. 相似文献
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In Catalonia (Spain), a variety of different systems have been built to naturally treat liquid residues from small communities. Some of these wastewater treatment plants (WWTPs) include constructed wetlands with horizontal subsurface flow (HSSF) as secondary treatment. The present study described and characterized the performance of 11 WWTPs with secondary HSSF constructed wetland systems after an initial operating period of 8 years. The effluent concentrations of Biochemical Oxygen Demand (BOD5), Total Suspended Solids (TSS), Total Nitrogen (TN) and Total Phosphorous (TP) were statistically analyzed, and removal efficiencies for all WWTPs including all stages in treatment were calculated. The accumulated probability functions of those parameters were evaluated to determine the influence of two different types of polishing units on the overall performance: (a) only lagoon systems and (b) lagoon systems with HSSF. The statistical analysis indicates good performance for BOD5 and TSS. In the first case, mean concentrations below 25 mg/L were found in 9 of the 11 plants analyzed and removal efficiencies between 78 and 96% were observed. In the second case, mean concentrations below 35 mg/L were found in 8 of the 11 plants, and removal efficiencies were between 65 and 88%. For the nutrients, the removal efficiency for TN and TP were in the range of 48-66% and 39-58%, respectively. Additionally, the analysis of the influence of the polishing units did not show a significant improvement (α > 0.05) for any parameter in the wetland systems without a subsequent polishing unit. However, in the wetland systems with a polishing unit of HSSF, a significant improvement (α < 0.05) was found for the effluent's BOD5, TN and TP concentrations but with no significant contribution in TSS management. 相似文献
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Double-stranded RNA (dsRNA) is a potent trigger of sequence-specific gene silencing mechanisms known as RNA silencing or RNA interference. The recognition of the target sequences is mediated by ribonucleoprotein complexes that contain 21- to 28-nucleotide (nt) guide RNAs derived from processing of the trigger dsRNA. Here, we review the experimental and bioinformatic approaches that were used to identify and characterize these small RNAs isolated from cells and tissues. The identification and characterization of small RNAs and their expression patterns is important for elucidating gene regulatory networks. 相似文献
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In this article, 30 speceis of bamboos, including 19 genera in 5 tribes, were collected and the morphology of fruits and starches of them was studied. The results are as follows.
I. The morphology of fruits is important in studies of systematic position in bamboos. According to the systems of W. Munro and G. Bentham whether the pericarp is adhesive to or
free from the seed coat may be taken as a basis of classification. It is also confirmed in this
article.
It is found in this work that all taxa with a binding pericarp and seed coat are of caryopsis that also has a ventral suture and hilum, while all others with a separated pericarp and
seed coat are of bacca or nut, which has no ventral suture and hilum. The former has a hard
and thin pericarp and rich endosperm, while the latter has a fleshy and thick pericarp and no
endosperm. These characteristics form a basis of classification of major groups.
II. In 1907, Brandis found that no any endosperm in matured fruit of Dinochloa, Melocalamus, Melocanna and Ochlandra. It has been proved by Stapf in at least one genus.
We found that the baccae of Qiongzhuea, Melocanna, Ferrocalamus and Chimonobambusa Subg.
Oerocalama were empty, with no endosperm. This may be a common character of the bacca.
We believe, therefore, that the systematic position of Qiongzhuea, Ferrocalamus and Chimonobambusa Subg. Oreocalama is close to Melocanneae.
III. Starch grains of bamboo fruits are complex in structure. They are round or ellipsoidal, consisting of 3-22 polyhedral or apple-like small grains. The morphology of starch
grains is not so important as fruit in bamboo classification, but some characteristics are of a
high value in the identification of genera and species, when they are combined with other
features. In Cephalostachyum, the starch grain is very big, with 20-40 μm in diam, and the
starch small grain is polyhedral or apple-like with 7.5-22.5 μm in diam, while in Dendrocalamus, the starch grain is small, with 10-28.9 μm in diam. and the starch small grain is
only polyhedral, with 3-11.9 μm in diam. The morphology and size of the starch grain and
starch small grain are also different in Melocanna and Chimonobambusa Subg. Oreocalama.
IV. W. Munro’s system divided Bambuseae into three major groups according to the morphology of flower and fruit. Because the material was not sufficient at that time, the system
wrongly put Cephalostachyum, Dendrocalamus into the group Bacciferea. Now it is found that
both Cephalostachyum and Dendrocalamus have a nut. Later G. Bentham found this problem
and divided the Bambuseae into four subtribes, treating Dendrocalamus as a separate subtribe,
Dendrocalamae, and putting the bacca group into another subtribe, Melocannae. It is better,
but it also has some shortcomings. Hackel, Gamble, E. G. Camus, A. Camus and Keng Pojie
all accepted the view of Bentham, placing Dendrocalamus and Melocanna into different subtribes or tribes. 相似文献
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增强型绿色荧光蛋白(enhanced green fluorescent protein,EGFP)是一种优化的突变型GFP,DFL是从甘菊中分离出的LFY基因的同源序列。为了研究DFL基因的功能和表达模式,研究利用小片段克隆法将linker序列插入到EGFP基因5′端启始密码子前面,在pBI121载体的CaMV35S启动子的3′端后面插入一段多克隆位点,成功地构建了pBI-DFL-EGFP表达载体。通过设计特异引物,利用PCR技术扩增得了到拟南芥LFY基因的启动子序列,用粘性末端PCR技术将pBI-DFL-EGFP表达载体中CaMV35S启动子替换成LFY基因启动子,构建成了pLFY-DFL-EGFP表达载体。用含有pBI-DFL-EGFP和pLFY-DFL-EGFP质粒的农杆菌侵染洋葱表皮细胞,在荧光显微镜下分别用蓝光激发,均观测到了荧光。这一结果表明,融合蛋白DFL∷EGFP表达载体构建成功,同时还证明了通过PCR技术克隆到的LFY启动子序列具有启动子功能。 相似文献
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