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981.
982.
Juno Jang Sung-Hwan Hong Dongwon Choi Kang-Seuk Choi Seongman Kang Ik-Hwan Kim 《Applied microbiology and biotechnology》2010,85(5):1509-1520
Newcastle disease virus (NDV) is not only one of the most economically important pathogen of poultry but also has a potential
as anticancer virotherapy. The role of NDV V protein in virus-production kinetics was investigated using DF-1 cell-based production
system. The presence of an anti-interferon (IFN)-alpha antibody resulted in enhanced NDV production kinetics in a dose-dependent
manner by blocking binding of NDV-induced IFN to its receptor. To prepare DF-1 cell whose cellular IFN signaling is blocked
efficiently, stable cell lines expressing either lentogenic or velogenic NDV V protein known as an IFN antagonist were established.
The overexpression of NDV V protein enhanced NDV production kinetics and expedited the rate of NDV production, while it had
no effect on Japanese encephalitis virus production. NDV V protein functions as an IFN antagonist by inhibiting the increase
in type I IFNs by NDV infection. The IFN signals in cells expressing NDV V protein were weakened by decreased activation or
expression of the dsRNA-activated enzymes. These IFN antagonist activities enhance rapid virus replication and spread in the
early phase of viral infection and will be useful in improving the production of viral vaccine strains. 相似文献
983.
Choong Hyun Lee Jung Hoon Choi Ki-Yeon Yoo Ok Kyu Park In Koo Hwang Sang Guan You Boo-Yong Lee Il-Jun Kang Moo-Ho Won 《Cellular and molecular neurobiology》2010,30(2):255-263
Melatonin exerts many physiological functions via its G protein-coupled receptors. In the present study, we investigated age-related
changes in MT2 melatonin receptor immunoreactivity and its levels in the gerbil hippocampus during normal aging. In the postnatal
month 1 (PM 1) group, MT2 immunoreaction was well observed in neurons in all subregions of the gerbil hippocampus. In the
PM 3 and 6 groups, MT2 immunoreactivity in neurons was decreased compared to that in the PM 1 group. Thereafter, MT2 immunoreactivity
in neurons was increased. In the PM 18 and 24 groups, MT2 immunoreactivity in neurons was strong in all subregions of the
gerbil hippocampus. In addition, the number of MT2 immunoreactive cells was lowest at PM 3 and highest at PM 24. From western
blot analysis, age-dependent change pattern in MT2 level in the gerbil hippocampus was similar to the immunohistochemical
result. These results indicate that MT2 immunoreactivity and levels are altered in the gerbil hippocampus during normal aging;
lowest at young adult stage and highest at aged stage. 相似文献
984.
Wei Yi Yang Sun Xufeng Wei Chunhu Gu Xiaochao Dong Xiaojun Kang Shuzhong Guo Kefeng Dou 《Molecular and cellular biochemistry》2010,337(1-2):9-16
Diets containing 8% salt or 4% fructose (FR) cause insulin resistance and increase tissue methylglyoxal and advanced glycation end products (AGEs), platelet cytosolic-free calcium, and systolic blood pressure (SBP) in rats. In WKY rats, we have shown that moderately high salt, 4% NaCl (MHS) alone in diet does not cause hypertension, and when given along with 4% FR it does not have an additive effect. N-acetylcysteine (NAC) or l-arginine (ARG), treatment alone does not prevent hypertension in this model. The objectives of this study were to investigate the effect of NAC plus ARG in diet on SBP, platelet cytosolic-free calcium in a MHS + FR model, and to measure the plasma levels of methylglyoxal and the AGE, methylglyoxal-derived hydroimidazolone (MGH). At 7 weeks of age, WKY rats were divided into three groups: control group was given regular rat chow (0.7% NaCl) and water; MHS + FR group, diet containing 4% NaCl and 4% FR in drinking water; and MHS + FR + NAC + ARG group, MHS diet supplemented with 1.5% N-acetylcysteine (NAC) and 1.5% l-arginine (ARG), and 4% FR in drinking water, and followed for 6 weeks. NAC + ARG prevented the increase in platelet cytosolic-free calcium and SBP in MHS + FR treated rats. There was no difference in mean values of plasma methylglyoxal and MGH among the groups. In conclusion, NAC + ARG treatment is effective in preventing hypertension in a moderately high salt + FR-induced animal model. Plasma methylglyoxal and MGH may not represent tissue modification or, alternatively, other tissue AGEs, derived from methylglyoxal or other aldehydes, may be involved in hypertension in this model. 相似文献
985.
986.
Min-Jung Kang Chul-Hwan Lee Young-Hoon Kang Il-Taeg Cho Tuan Anh Nguyen Yeon-Soo Seo 《Nucleic acids research》2010,38(21):7611-7625
The two endonucleases, Rad27 (yeast Fen1) and Dna2, jointly participate in the processing of Okazaki fragments in yeasts. Mus81–Mms4 is a structure-specific endonuclease that can resolve stalled replication forks as well as toxic recombination intermediates. In this study, we show that Mus81–Mms4 can suppress dna2 mutational defects by virtue of its functional and physical interaction with Rad27. Mus81–Mms4 stimulated Rad27 activity significantly, accounting for its ability to restore the growth defects caused by the dna2 mutation. Interestingly, Rad27 stimulated the rate of Mus81–Mms4 catalyzed cleavage of various substrates, including regressed replication fork substrates. The ability of Rad27 to stimulate Mus81–Mms4 did not depend on the catalytic activity of Rad27, but required the C-terminal 64 amino acid fragment of Rad27. This indicates that the stimulation was mediated by a specific protein–protein interaction between the two proteins. Our in vitro data indicate that Mus81–Mms4 and Rad27 act together during DNA replication and resolve various structures that can impede normal DNA replication. This conclusion was further strengthened by the fact that rad27 mus81 or rad27 mms4 double mutants were synergistically lethal. We discuss the significance of the interactions between Rad27, Dna2 and Mus81–Mms4 in context of DNA replication. 相似文献
987.
Choong Hyun Lee Ki-Yeon Yoo Ok Kyu Park Jung Hoon Choi Il-Jun Kang Eunjoo Bae Sung Koo Kim In Koo Hwang Moo-Ho Won 《Molecules and cells》2010,29(4):373-378
Phosphorylated extracellular signal-regulated kinase (pERK) mediates neuronal synaptic plasticity, long-term potentiation,
and learning and memory in the hippocampus. In this study, we examined pERK1/2 immunoreactivity and its protein level in the
gerbil hippocampus at various ages. In the postnatal month 1 (PM 1) group, very weak pERK1/2 immunoreactivity was detected
in the hippocampus. In the CA1 region, pERK1/2 immunoreactivity was considerably increased in the stratum pyramidale in the
PM 6 group. Thereafter, pERK1/2 immunoreactivity was decreased. In the CA2/3 region, pERK1/2 immunoreactivity increased in
an age-dependent manner until PM 12. Thereafter, numbers of pERK1/2-immunoreactive neurons were decreased. However, in the
mossy fiber zone, pERK1/2 immunostaining became stronger with age. In the dentate gyrus, a few pERK1/2-immunoreactive cells
were observed until PM 12. In the PM 18 and 24 groups, numbers of pERK1/2-immunoreactive cells were increased, especially
in the polymorphic layer. In Western blot analysis, pERK1/2 level in the gerbil hippocampus was increased with age. These
results indicate that total pERK1/2 levels are increased in the hippocampus with age. However pERK1/2 immunoreactivity in
subregions of the gerbil hippocampus was changed with different pattern during normal aging. 相似文献
988.
989.
Tomohiro Yamaguchi Takashi Fujii Yoshito Abe Teruhisa Hirai Dongchon Kang Keiichi Namba Naotaka Hamasaki Kaoru Mitsuoka 《Journal of structural biology》2010,169(3):406-412
The C-terminal membrane domain of erythrocyte band 3 functions as an anion exchanger. Here, we report the three-dimensional (3D) structure of the membrane domain in an inhibitor-stabilized, outward-open conformation at 18 Å resolution. Unstained, frozen-hydrated tubular crystals containing the membrane domain of band 3 purified from human red blood cells (hB3MD) were examined using cryo-electron microscopy and iterative helical real-space reconstruction (IHRSR). The 3D image reconstruction of the tubular crystals showed the molecular packing of hB3MD dimers with dimensions of 60 × 110 Å in the membrane plane and a thickness of 70 Å across the membrane. Immunoelectron microscopy and carboxyl-terminal digestion demonstrated that the intracellular surface of hB3MD was exposed on the outer surface of the tubular crystal. A 3D density map revealed that hB3MD consists of at least two subdomains and that the outward-open form is characterized by a large hollow area on the extracellular surface and continuous density on the intracellular surface. 相似文献
990.
Guo-Liang Qian Jia-Qin Fan De-Feng Chen Yue-Jing Kang Bing Han Bai-Shi Hu Feng-Quan Liu 《Biological Control》2010,52(1):17-23
An N-acyl homoserine lactonase gene aiiA, transcribed by a strong and constitutive Escherichia coli promoter Plpp (Accession No. EU723847), was transformed into Lysobacter enzymogenes strain OH11, creating strain OH11A. The N-acyl-homoserine lactone (AHL)-degradation assay showed that transformant OH11A acquired the ability to degrade AHL molecules produced by Agrobacterium tumefaciens, Pectobacterium carotovorum, Pseudomonas syringae pv. tomato strain DC3000 and Acidovorax avenae subsp. citrulli. Pathogenicity tests showed that while the parental strain OH11 did not reduce P. carotovorum infection, the transformant OH11A caused a strong reduction of Pectobacterium virulence on Chinese cabbage and cactus, whereas strain OH11A did not seem to interfere with the normal growth of this pathogen in cabbages. In antimicrobial activity assays, strain OH11A and OH11 showed similar antimicrobial activity against Phytophthora capsici and Sclerotinia sclerotiorum. This work provided a new strategy for developing genetically engineered multi-functional L. enzymogenes strains that possessed the ability to biologically control fungal pathogens and reduce bacterial pathogenicity. 相似文献