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991.
Mass spectrometry (MS)-based characterization is important in proteomic research for verification of structural features and functional understanding of gene expression. Post-translational modifications (PTMs) such as methylation and acetylation have been reported to be associated with chromatin remodeling during spermatogenesis. Although antibody- and MS-based approaches have been applied for characterization of PTMs on H3 variants during spermatogenesis, variant-specific PTMs are still underexplored. We identified several lysine modifications in H3 variants, including testis-specific histone H3 (H3t), through their successful separation with MS-based strategy, based on differences in masses, retention times, and presence of immonium ions. Besides methylation and acetylation, we detected formylation as a novel PTM on H3 variants in mouse testes. These patterns were also observed in H3t. Our data provide high-throughput structural information about PTMs on H3 variants in mouse testes and show possible applications of this strategy in future proteomic studies on histone PTMs. 相似文献
992.
Dong Hoon Kwak Sung Yun Heo Chang-Hyun Kim Ji-Su Kim Sun-Uk Kim Kyu-Tae Chang 《Animal cells and systems.》2016,20(4):203-212
Plant-derived multiple monoclonal antibody (mAb) CO17-1A?×?BR55 (mAbP CO17-1A?×?BR55) produced in transgenic tobacco plants were cross-pollinated with mAb CO17-1A and mAb BR55. Human anti-colorectal cancer multiple mAb CO17-1A?×?BR55 was cloned using pBI121 vector. Mice were given a single intraperitoneal injection of azoxymethane (AOM) with 10?mg/kg body weight. Starting 1 week after the injection, mice received 2% dextran sulfate sodium (DSS) in the drinking water for 1 week. In addition, the mice were injected intraperitoneal with mAbs dissolved in phosphate buffered saline (100?μg/mouse) twice per week for 4 weeks. Apoptotic cell death, expression of pro-apoptotic proteins, activity of inflammatory cytokines and ERK pathway phosphorylation were assayed by Western blot and TUNEL kit. mAbP CO17-1A?×?BR55 meaningfully and efficiently suppressed the development of AOM/DSS-induced colorectal inflammation and colorectal tumors, as determined by a reduced activation of inflammatory cytokines, number of colorectal tumor-induced mouse, number of tumor per mouse colon than other mAbs. Cell death by apoptosis was much increased in the mAbP CO17-1A?×?BR55-treated tumor compared with negative control. Apoptotic cell death and expression of pro-apoptotic proteins including Bax and cleaved caspase-3 were highest in treatment with mAbP CO17-1A?×?BR55. In addition, mAbP CO17-1A?×?BR55 was meaningfully decreased the expression of inflammatory cytokines, including COX-2, iNOS, p50 and p65, but the expression of PPARγ was significantly increased compared with AOM/DSS-induced carcinogenesis negative control. Moreover, mAbP CO17-1A?×?BR55 meaningfully repressed the ERK1/2 phosphorylation in AOM/DSS-induced colorectal tumors. Therefore, our results suggest that multiple mAbP CO17-1A?×?BR55 have meaningful effects of anti-inflammation related with the anti-carcinogenesis in AOM/DSS-induced colorectal tumor by inhibition of ERK1/2 phosphorylation. 相似文献
993.
Mean molal activity coefficients of simple electrolyte in aqueous solutions of Li, Na, K or Cs salts of dextransulfate (DS) with added LjCl, NaCl, KCl or CsCl are reported. The measurements were carried out by means of an electrochemical cell method using a cation exchange membrane as cation selective electrode and Ag/AgCl electrodes. For LiDS-LiCl, NaDS-NaCl and CsDS-CsCl systems the polymer concentration, mp, was varied from 0.0088 to 0.113 m and at a given mp the ratio X of the polymer to salt concentration was varied from 0.5 to 16. Due to the insolubility of KDS in high concentration of KCl, the measurements on KDS-KCl system were performed in the mp range of 0.0088–0.089 m and some of the smaller X values were omitted. The activity coefficient results are compared to Manning's limiting laws, the additivity rule, and to new limiting laws. The additivity rule can give an excellent representation of the data for all mp values when γp is used as an adjustable parameter. 相似文献
994.
Isotherms for the binding of dodecyltrimethylammonium (DTA+) and tetradecyltrimethylammonium (TTA+) ions by DNA in aqueous solution at 30°C are reported. The binding isotherms were determined using a potentiometric technique with cationic surfactant-selective electrodes. The DNA concentrations used are 5 × 10?4 and 10?3 equiv./kg, Surfactant concentrations varying from 3 × 10?6M to the critical micelle concentration. The influence of added NaCl (0.01 M) on the binding process is studied. The binding process is shown to be highly cooperative. Applying the binding theory of Schwarz and of Satake and Yang, binding constants and cooperativity parameters can be calculated. The binding constant K is found to be 1.2kT larger for TTA+ than for DTA+ in salt-free solution, and 1.4kT larger for TTA+ than for DTA+ in 0.01 M NaCl. The cooperativity parameter u is about 1.4kT larger for TTA+ in salt-free solution and 1.2kT larger in 0.01 M NaCl. It is concluded that the hydrophobic part of the bound surfactant is not completely immersed in the hydrophobic DNA core, but also interacts with other surfactant molecules. This situation is compared to the case of micelle formation. 相似文献
995.
In this study, the complete mitochondrial genome of the Eurasian flying squirrel Pteromys volans (Rodentia, Sciuromorpha, Sciuridae) was sequenced and characterized in detail. The entire mitochondrial genome of P. volans consisted of 16,513 bp and contained 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and two non-coding regions. Its gene arrangement pattern was consistent with the mammalian ground pattern. The overall base composition and AT contents were similar to those of other rodent mitochondrial genomes. The light-strand origin generally identified between tRNA Asn and tRNA Cys consisted of a secondary structure with an 11-bp stem and an 11-bp loop. The large control region was constructed of three characteristic domains, ETAS, CD, and CSB without any repeat sequences. Each domain contained ETAS1, subsequences A, B, and C, and CSB1, respectively. In order to examine phylogenetic contentious issues of the monophyly of rodents and phylogenetic relationships among five rodent suborders, here, phylogenetic analyses based on nucleotide sequence data of the 35 rodent and 3 lagomorph mitochondrial genomes were performed using the Bayesian inference and maximum likelihood method. The result strongly supported the rodent monophyly with high node confidence values (BP 100 % in ML and BPP 1.00 in BI) and also monophylies of four rodent suborders (BP 85–100 % in ML and BPP 1.00 in BI), except for Anomalumorpha in which only one species was examined here. Also, phylogenetic relationships among the five rodent suborders were suggested and discussed in detail. 相似文献
996.
Jinglei Cai Sungwook Kwak Jong-Min Lee Eun-Jung Kim Min-Jung Lee Gi-Hee Park Sung-Won Cho Han-Sung Jung 《Cell and tissue research》2010,341(2):251-258
Teeth, an excellent model for studying organogenesis, develop from a series of epithelial–mesenchymal interactions that are
mediated by a complex molecular network. Bcor (BCL-6 interacting corepressor) has recently been discovered, but little is known about its function in tooth development.
Mutations in BCOR affect humans with oculofaciocardiodental syndrome, which is an X-linked dominant disorder with presumed male lethality and
which comprises microphthalmia, congenital cataracts, radiculomegaly, and cardiac and digital abnormalities. In this study,
the Bcor expression pattern has been intensively investigated during mouse molar development. Bcor is expressed in both dental epithelium and the mesenchyme at E11.5. To understand the function of Bcor, knockdown of Bcor has been examined by using lentivirus-mediated RNA interference. Silencing of Bcor expression in dental mesenchymal cells at E14.5 causes dentinogenesis defects and retardation of tooth root development.
Thus, our results suggest that Bcor expressed in the mesenchyme plays crucial roles during early tooth development. The function of Bcor expressed in the epithelium remains to be elucidated. 相似文献
997.
Siyoung Lee Youngmin Lee Kwangwon Hong Jaewoo Hong Suyoung Bae Jida Choi Hyunjhung Jhun Areum Kwak Eunsom Kim Seunghyun Jo Charles A Dinarello Soohyun Kim 《Molecular medicine (Cambridge, Mass.)》2013,19(1):65-71
α1-Antitrypsin (AAT) is a member of the serine proteinase inhibitor family that impedes the enzymatic activity of serine proteinases, including human neutrophil elastase, cathepsin G and neutrophil proteinase 3. Here, we expressed recombinant AAT by fusing the intact AAT gene to the constant region of IgG1 to generate soluble recombinant AAT-Fc protein. The recombinant AAT-Fc protein was produced in Chinese hamster ovary (CHO) cells and purified using mini-protein A affinity chromatography. Recombinant AAT-Fc protein was tested for antiinflammatory function and AAT-Fc sufficiently suppressed tumor necrosis factor (TNF)-α–induced interleukin (IL)-6 in human peripheral blood mononuclear cells (PBMCs) and inhibited cytokine-induced TNFα by different cytokines in mouse macrophage Raw 264.7 cells. However, AAT-Fc failed to suppress lipopolysaccharide-induced cytokine production in both PBMCs and macrophages. In addition, our data showed that AAT-Fc blocks the development of hyperglycemia in a streptozotocin-induced mouse model of diabetes. Interestingly, we also found that plasma-derived AAT specifically inhibited the enzymatic activity of elastase but that AAT-Fc had no inhibitory effect on elastase activity. 相似文献
998.
999.
Huen Lee Won-Hi Hong Ji-Ho Yoon Kyu-Min Song Sang-Soo Kwak Jang-Ryol Liu 《Biotechnology Techniques》1992,6(2):127-130
Summary Indole alkaloids, particularly vindoline and catharanthine, were extracted from the leaves ofCatharanthus roseus by supercritical extraction with CO2. The contents of vindoline and catharanthine in the extracts were determined by HPLC and identified by LC/MS. About 52 %(w/w)
of the initial vindoline content, 1.5 mg vindoline/g dry wt leaves, was recovered after extracting this material for 10 h
with the CO2 flow rate of 400 ml/min at 40°C and 150 bar. Vindoline concentration in the extract was 67 %(w/w). 相似文献
1000.
Lee Haeng-Soon Kwon Eun-Jeong Kwon Suk-Yoon Jeong Yu-Jeong Lee Eun-Mo Jo Man-Hyun Kim Hyun-Sook Woo In-Sik Shinmyo Atsuhiko Yoshida Kazuya Kwak Sang-Soo 《Molecular breeding : new strategies in plant improvement》2003,11(3):213-220
Superoxide dismutase (SOD) plays an important role in cellular defense against oxidative stress in aerobic organisms. To generate cucumber (Cucumis sativus L.) fruits producing high yields of SOD for an anti-aging cosmetic material as a plant bioreactor, the CuZnSOD cDNA (mSOD1) from cassava was introduced into cucumber fruits by Agrobacterium-mediated transformation using the ascorbate oxidase promoter with high expression in fruits. The bialaphos-resistant shoots were selected on medium containing MS basal salts, 2 mg l–1 BA, 0.1 mg l–1 IAA, 300 mg l–1 claforan, and 2 mg l–1 bialaphos. After 6 weeks of culture on the selection medium, the shoots were transferred to MS medium containing 1 mg l–1 IAA, 300 mg l–1 claforan, 2 mg l–1 bialaphos to induce roots. Southern blot analysis confirmed that the mSOD1 gene was properly integrated into the nuclear genomes of three cucumber plants tested. The mSOD1 gene was highly expressed in the transgenic cucumber fruits, whereas it was expressed at a low level in the transgenic leaves. The SOD specific activity (units/mg protein) in transgenic fruits was approximately 3 times higher than in those of non-transgenic plants. 相似文献