• Title/Summary/Keyword: B/K protein

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Type 3 muscarinic acetylcholine receptor stimulation is a determinant of endothelial barrier function and adherens junctions integrity: role of protein-tyrosine phosphatase 1B

  • Jiao, Zhou-Yang;Wu, Jing;Liu, Chao;Wen, Bing;Zhao, Wen-Zeng;Du, Xin-Ling
    • BMB Reports
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    • v.47 no.10
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    • pp.552-557
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    • 2014
  • The main purpose of this study was to investigate whether type 3 muscarinic acetylcholine receptor (M3R) dysfunction induced vascular hyperpermeability. Transwell system analysis showed that M3R inhibition by selective antagonist 4-diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP) and small interfering RNA both increased endothelial permeability. Using coimmunoprecipitation and Western blot assay, we found that M3R inhibition increased VE-cadherin and ${\beta}$-catenin tyrosine phosphorylation without affecting their expression. Using PTP1B siRNA, we found that PTP1B was required for maintaining VE-cadherin and ${\beta}$-catenin protein dephosphorylation. In addition, 4-DAMP suppressed PTP1B activity by reducing cyclic adenosine monophosphate (cAMP), but not protein kinase $C{\alpha}$ ($PKC{\alpha}$). These data indicate that M3R preserves the endothelial barrier function through a mechanism potentially maintaining PTP1B activity, keeping the adherens junction proteins (AJPs) dephosphorylation.

Inhibition of the Replication of Hepatitis C Virus Replicon with Nuclease-Resistant RNA Aptamers

  • Shin, Kyung-Sook;Lim, Jong-Hoon;Kim, Jung-Hye;Myung, Hee-Joon;Lee, Seong-Wook
    • Journal of Microbiology and Biotechnology
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    • v.16 no.10
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    • pp.1634-1639
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    • 2006
  • Hepatitis C virus (HCV)-encoded nonstructural protein 5B (NS5B) possesses RNA-dependent RNA polymerase activity, which is considered essential for viral proliferation. Thus, HCV NS5B is a good therapeutic target protein for the development of anti-HCV agents. In this study, we isolated two different kinds of nuclease-resistant RNA aptamers with 2'-fluoro pyrimidines against the HCV NS5B from a combinatorial RNA library with 40 nucleotide random sequences, using SELEX technology. The isolated RNA aptamers were observed to specifically and avidly bind the HCV NS5B with an apparent $K_d$ of 5 nM and 18 nM, respectively, in contrast with the original RNA library that hardly bound the target protein. Moreover, these aptamers could partially inhibit RNA synthesis of the HCV subgenomic replicon when transfected into Huh-7 hepatoma cell lines. These results suggest that the RNA aptamers selected in vitro could be useful not only as therapeutic agents of HCV infection but also as a powerful tool for the study of the HCV RNA-dependent RNA polymerase mechanism.

Molecular Characterization of a cDNA Encoding Chlorophyll a/b Binding Protein (Cab) from Panax ginseng C. A. Meyer (고려인삼 Chlorophyll a/b Binding Protein(Cab) 유전자의 동정 및 분자적인 특성분석)

  • In Jun Gyo;Lee Bum Soo;Youn Jae-Ho;Son Hwa;Kim Se Young;Yang Deok Chun
    • Korean Journal of Plant Resources
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    • v.18 no.3
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    • pp.441-449
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    • 2005
  • Photo system II (PSII) is one of the two photosynthetic reaction centers in the chloroplast of higher plants. The chlorophyll a/b-light harvesting complex serves primarily as an antenna for PSII. We isolated a cDNA that encodes a chlorophyll a/b-binding protein (Cab) from Panax ginseng. The small subunit consists of 935 nucleotides long and has an open reading frame of 795 bp with the deduced amino acid of 265 residues (pI 5.63), 28.6 kDa. The deduced amino acid sequence matched to the previously reported Cab genes. Their degree of amino acid identity ranged from 68 to $92\%$. Phylogenetic analysis based on the amino acid residues was showed that the ginseng Cab gene was grouped with P. persica (AAC34983), A. thaliana (AAD28771), G. hirsutum (CAA38025), G. max (AAL29886), and V. radiate (AAF89205).

Effects of k-Casein Variants on Milk Yield and Composition in Dairy Cattle

  • Chung, Eui-Ryong;Chung, Ku-Young
    • Food Science of Animal Resources
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    • v.25 no.3
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    • pp.328-332
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    • 2005
  • The effect of k-casein (k-CN) variant on milk production traits (milk yield, fat yield, protein yield, fat percentage and protein percentage) was estimated for 568 Holstein cows in the first lactation. The k-CN valiant were determined by PCR-RFLP (restriction fragment length polymorphism) technique at the DNA level. Single trait linear model was used for the statistical analysis of the data. Result of this study indicated that k-CN variant affected significantly milk yield (P<0.05) and protein yield (P<0.01). Animals with the BB variant produced 622kg milk more and had protein yield higher by 32kg compared with animals with the AA variant No associations between the k-CN variants and other milk production trait were found. Therefore, milk and protein yield may be improved through milk protein typing by increasing the frequencies of k-CN B variant in dairy cattle population. In cheese making, it will be also preferable to have milk with the B variant of k-CN, which gives higher yield having a better quality than the A variant milk.

Effects of Lowering the Dietary Levels of Energy, Protein and Amino Acid (Methionine and Cysteine) on the Performance of Laying Hens

  • Serpunja, Subin;Balasubramanian, Balamuralikrishnan;Kim, In Ho
    • Korean Journal of Poultry Science
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    • v.44 no.2
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    • pp.67-73
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    • 2017
  • The purpose of our study was to determine the effects of varying levels of energy, protein, and amino acids on the performances of laying hens. A total of 240 Hy-Line Brown laying hens at 36 weeks of age were used in this 4-week feeding trial. The hens were randomly allocated to five treatment diets, with eight replications of six hens in each replicate cage. The treatment diets were as follows: A- basal diet + 18% crude protein, metabolizable energy 2,800 kcal, total (methionine + cysteine) 0.65%; B- basal diet + 17% crude protein, metabolizable energy 2,700 kcal, total (methionine + cysteine) 0.59%; C- basal diet + 16.5% crude protein, metabolizable energy 2,700 kcal, total (methionine + cysteine) 0.59%; D- basal diet + 16.5% crude protein, metabolizable energy 2,700 kcal, total (methionine + cysteine) 0.54%; and E- basal diet + 16% crude protein, metabolizable energy 2,680 kcal, total (methionine + cysteine) 0.54%. The study results revealed that the hen-day egg production of hens that were fed with low-energy diets (B, C, and D) was comparable with that of hens fed with high-energy diet A, whereas average daily feed intake in hens fed treatment diet D and E was significantly higher (P<0.05) than that in hens fed treatment diet A. Overall, the eggshell thickness was unaffected by any of the treatment diets. Egg weight was comparable among the treatment diets, except for treatment diet E. Haugh unit improved with decreasing levels of dietary energy, protein, and methionine + cysteine in the diet. We can summarize that laying hens fed with low dietary energy and low crude protein treatment diets B, C, and D had satisfactory performance compared with those fed with high-energy treatment diet A. This indicates that there is the potential to reduce feed costs by formulating diets with lower energy and low protein levels.

Biological Activity and Biochemical Properties of Silkworm (Bombyx mori L.) Powder Fermented with Bacillus subtilis and Aspergillus kawachii (유용식용 균주에 의한 발효 누에분말의 이화학적 특성과 생리활성)

  • Cha, Jae-Young;Kim, Yong-Soon;Ahn, Hee-Young;Kang, Min-Jung;Heo, Su-Jin;Cho, Young-Su
    • Journal of Life Science
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    • v.21 no.1
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    • pp.81-88
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    • 2011
  • Biological activities (${\alpha},{\alpha}'$-diphenyl-${\beta}$-picrylhydrazyl (DPPH) free radical scavenging activity, fibrinolytic activity and reducing power) and biochemical properties (protein content and electrophoretical protein patterns) were examined in solid state fermentation with Bacillus subtilis and Aspergillus kawachii using silkworm powder (SP) as substrate. The highest protein contents and free radical scavenging activities were seen in the SP fermented for 12 days with B. subtilis and A. kawachii, and these were in a time-dependent manner. The highest reducing power was seen in the SP fermented for 6 days with B. subtilis and for 12 days with A. kawachii, respectively. The highest fibrinolytic activities were seen in silkworm fermented for 6 days with B. subtilis and A. kawachii, but this activity was higher in the A. kawachii fermented SP than that of B. subtilis. When total protein patterns were analyzed by SDS-polyacrylamide gel electrophoresis (PAGE), the proteins of the SP fermented with B. subtilis for 3 days were completely degraded, while the protein degradation in the SP fermented with A. kawachii occurred after 12 days and this degradation increased proportionally to culture time. As a result, the SP fermented with both B. subtilis and A. kawachii showed higher fibrinolytic activities after 6 days of fermentation and antioxidative activity after 12 days, indicating that physiological activities of the fermented SP using these strains were highly improved compared to the unfermented SP, and that this compound could be a candidate material as a dietary supplement of healthy functional foods.

Apigenin Inhibits Tumor Necrosis Factor-α-Induced Production and Gene Expression of Mucin through Regulating Nuclear Factor-Kappa B Signaling Pathway in Airway Epithelial Cells

  • Seo, Hyo-Seok;Sikder, Mohamed Asaduzzaman;Lee, Hyun Jae;Ryu, Jiho;Lee, Choong Jae
    • Biomolecules & Therapeutics
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    • v.22 no.6
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    • pp.525-531
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    • 2014
  • In the present study, we investigated whether apigenin significantly affects tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$)-induced production and gene expression of MUC5AC mucin in airway epithelial cells. Confluent NCI-H292 cells were pretreated with apigenin for 30 min and then stimulated with TNF-${\alpha}$ for 24 h or the indicated periods. The MUC5AC mucin gene expression and mucin protein production were measured by reverse transcription - polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA), respectively. Apigenin significantly inhibited MUC5AC mucin production and down-regulated MUC5AC gene expression induced by TNF-${\alpha}$ in NCI-H292 cells. To elucidate the action mechanism of apigenin, effect of apigenin on TNF-${\alpha}$-induced nuclear factor kappa B (NF-${\kappa}B$) signaling pathway was also investigated by western blot analysis. Apigenin inhibited NF-${\kappa}B$ activation induced by TNF-${\alpha}$. Inhibition of inhibitory kappa B kinase (IKK) by apigenin led to the suppression of inhibitory kappa B alpha ($I{\kappa}B{\alpha}$) phosphorylation and degradation, p65 nuclear translocation. This, in turn, led to the down-regulation of MUC5AC protein production in NCI-H292 cells. Apigenin also has an influence on upstream signaling of IKK because it inhibited the expression of adaptor protein, receptor interacting protein 1 (RIP1). These results suggest that apigenin can regulate the production and gene expression of mucin through regulating NF-${\kappa}B$ signaling pathway in airway epithelial cells.

Revision of Structures of Flavanoids from Scutellaria indica and Their Protein Tyrosine Phosphatase 1B Inhibitory Activity

  • Min, Byung-Sun
    • Natural Product Sciences
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    • v.12 no.4
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    • pp.205-209
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    • 2006
  • The structures of flavonoids, 2(S)-5,7-dihydroxy-8,2'-dimethoxyflavanone (1), wogonin (2), 2(S)-5,7, 2'-trihydroxy-8-methoxyflavanone (3), and 2(S)-5,2',5'-trihydroxy-7,8-dimethoxyflavanone (4), isolated from Scutellaria indica were revised on the basis of 2D NMR spectroscopy, including to gCOSY, gHSQC, and gHMBC. Compounds 1-4 were tested in vitro protein tyrosine phosphatase 1B (PTP1B) inhibitory activity. Compounds 2 and 4 exhibited weak PTP1B inhibitory activity with $IC_{50}$ values of 208 and $337{\mu}M$, respectively.

Expression of Mouse Synaptobrevin (VAMP) Gene in E. coli and its Cleavage by the Clostridium botulinum type B Toxin (Synaptobrevin (VAMP)유전자의 대장균에서의 발현 및 Clostridium botulinum type B 독소에 의한 절단)

  • 정현호;양기혁;이상달;양규환
    • Toxicological Research
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    • v.13 no.4
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    • pp.417-421
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    • 1997
  • Synaptobrevin is a kind of vesicle associated membrane proteins (VAMPs) which plays a secretary role in the neuronal synapse and was recently known as the biochemical target of botulinum neurotoxin type B. The structural gene of the synaptobrevin was cloned from mouse brain using RT-PCR technique and was seqrtenced. The deduced amino acid sequence showed that the synaptobrevin protein from mouse brain is exactly the same with that of the rat brain in the amino acid level. The synaptobrevin gene was subcloned into pET3a vector and expressed in E. coli. The molecular weight of the recombinant protein was 19 kDa as expected. Moreover, when the recombinant synaptobrevin protein was incubated with the native neurotoxin of Clostridium botulinum type B, it was cleaved by the toxin in a time dependent manner. This implies that the recombinant synaptobrevin protein and the native toxin are reacted in the same way as the native synaptobrevin did in the neuronal cells.

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Differential Effects of Fumonisin $B_1$ on Cell Death in Cultured Cells: the Significance of the Elevated Sphinganine

  • Yu, Chang-Hun;Lee, Yong-Moon;Yun, Yeo-Pyo;Yoo, Hwan-Soo
    • Archives of Pharmacal Research
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    • v.24 no.2
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    • pp.136-143
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    • 2001
  • Fumonisins are specific inhibitors of ceramide synthase in sphingolipid metabolism. An alteration in sphingolipid metabolism as a result of fumonisin exposure is related to cell death (Yoo et al., 1992). The objective of this study was to investigate whether elevated free sphinganine levels are related to the sensitivity of cultured cells to fumonisin exposure. Fumonisin $B_1$ elevated the intracellular free sphinganine concentraions in both LLC-$PK_1$ and Chinese hamster ovary (CHO) cells. However, CHO cells are resistant to fumonisin cytotoxicity at 50${u}m$, while LLC-$PK_1$ cells are sensitive at concentrations greater than 357M. The intracellular concentration of free sphinganine in LLC-$PK_1$ cells treated at 50${u}m$ fumonisin $B_1$ for 72 h was approximately 1450 pmol/mg protein relative to the 37 pmol observed in the control culture. Under the same conditions, the population of apoptotic cells in the 50${u}m$ fumonisin $B_1$-treated culture was approximately 37% of the total compared to 12% in the control. The caspase III-like activity after 72 h in the 50${\mu}$M fumonisin $B_1$-exposed culture Increased to approximately 50 $pmol/mg$ protein/hr compared to 6 $pmol/mg$ protein/hr in the control. L-cycloserine, a serine palmitoyltransferase inhibitory reduced the fumonisin $B_1$-stimulated caspase III-like activity down to the control level. Under the same culture conditions, the intracellular concentration of free sphinganine after-cycloserine plus fumonisin $B_1$ treatment was 140 pmol/mg protein compared to 1450 $pmol/mg$ protein in fumonisin $B_1$ alone. The intracellular concentration of free sphinganine in CHO cells treated with 50${u}m$ fumonisin $B_1$ for 72 h was al)proximately 460 pmol/mg protein, indicating that the mass amount of elevated free sphinganine in the CHO cells was about 32% of that in LLC-$PK_1$ cells. Adding exogenous sphinganine to the CHO cells along with 50${u}m$ fumonisin $B_1$ treatment for 72 h caused both necrosis and apoptosis. In conclusion, the elevated endogenous sphinganine acts as a contributing factor to the fumonisin-induced cell death.

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