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91.
To investigate the effect of Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) on human cancer cells, we sought to identify and analyze potential target genes that were differentially expressed in the presence and absence of LMP1. Our cDNA microarray analysis revealed that expression of early growth response gene-1 (Egr-1) was increased by LMP1 expression in MCF7 and Jurkat cells. An NFkappaB inhibitor (SN50) antagonized LMP1-induced enhancement of Egr-1 expression, indicating that LMP1 induced Egr-1 via NFkappaB. Furthermore, three lines of evidence indicated that Egr-1 was required for LMP1-induced cancer cell survival. First, Egr-1 expression enhanced the survival of doxorubicin-treated MCF7 cells. Second, inhibition of Egr-1 expression by siRNA (siEgr-1) effectively suppressed LMP-1-induced survival of MCF7 cells. Third, Egr-1 knockdown decreased LMP1-induced expression of Bfl-1. Similar relationships among EBV infection, Egr-1 and drug resistance were also observed in tissues of peripheral T-cell lymphoma-unspecified (PTCL-u) patients. 相似文献
92.
Rajesh Kumar Tewari Soo Yeon Lee Eun Joo Hahn Kee Yoeup Paek 《Plant biotechnology reports》2007,1(4):227-235
Nitric oxide (NO) is a diffusible, gaseous signaling molecule. In plants, NO influences growth and development, and it can
also affect plant responses to various stresses. Because NO induces root differentiation and interacts with reactive oxygen
species, we examined the temporal effect of NO elicitation on root growth, saponin accumulation and antioxidant defense responses
in the adventitious roots of mountain ginseng (Panax ginseng). The observations revealed that NO is involved in root growth and saponin production. Elicitation with sodium nitroprusside
(SNP) activated O2
−-generating NADPH oxidase (NOX) activity, which most probably subsequently enhanced growth of adventitious roots of mountain
ginseng. A severe inhibition of NOX activity and decline in dry weight of SNP elicited adventitious roots in the presence
of NOX inhibitor (diphenyl iodonium, DPI), which further supports involvement of NOX in root growth. Enhanced activities of
antioxidant enzymes by SNP appear to be responsible for low H2O2, less lipid peroxidation, and modulation of ascorbate and non-protein thiol statuses in the adventitious roots of mountain
ginseng. Dry mass, saponin content and NOX activity was related with NO content present in adventitious roots of mountain
ginseng. 相似文献
93.
Microsomal prostaglandin E2 synthase (mPGES-1) has been identified recently as a novel target for treating pain and inflammation. The aim of this study
is to understand the binding affinities of reported inhibitors for mPGES-1 and further to design potential new mPGES-1 inhibitors.
3D-QSAR-CoMFA (comparative molecular field analysis) and CoMSIA (comparative molecular similarity indices analysis) - techniques
were employed on a series of indole derivatives that act as selective mPGES-1 inhibitors. The lowest energy conformer of the
most active compound obtained from systematic conformational search was used as a template for the alignment of 32 compounds.
The models obtained were used to predict the activities of the test set of eight compounds, and the predicted values were
in good agreement with the experimental results. The 3D-QSAR models derived from the training set of 24 compounds were all
statistically significant (CoMFA; q
2 = 0.89, r
2 = 0.95, , and CoMSIA; q
2 = 0.84, r
2 = 0.93, , ). Contour plots generated for the CoMFA and CoMSIA models reveal useful clues for improving the activity of mPGES-1 inhibitors.
In particular, substitutions of an electronegative fluorine atom or a bulky hydrophilic phenoxy group at the meta or para positions of the biphenyl rings might improve inhibitory activity. A plausible binding mode between the ligands and mPGES-1
is also proposed. 相似文献
94.
A proteomic approach has been adopted to investigate the low-abundant proteins in rice leaf in response to cold stress. Rice seedlings were exposed to different temperatures, such as 5 or 10 degrees C, and samples were collected after different time course. To eliminate the high-abundant proteins in leaf tissues such as ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), proteins were fractionated by polyethylene glycol (PEG). The elimination of Rubisco from the protein samples was confirmed by Western blot analysis. The PEG fractionated protein samples were separated by 2-DE and visualized by silver or CBB staining. A total 12 up-regulated protein spots were identified using the analysis of MALDI-TOF mass spectrometry or ESI MS/MS. We identified some novel proteins such as cysteine proteinase, thioredoxin peroxidase, a RING zinc finger protein-like, drought-inducible late embryogenesis abundant, and a fibrillin-like protein that had not yet been reported in the earlier reports on cold proteomic analysis. The identification of some novel low-abundant proteins in response to cold stress may provide a new homeostasis to develop enhanced cold tolerance transgenic plants. Thus, we propose that a PEG fractionation system can be used as an influential protein extraction method from the leaf samples, which can lead to knowledge of the expression pattern of low-abundant proteins in response to various biotic or abiotic stresses. 相似文献
95.
Kyung Eun Kim Eun Ae Jeong Hyun Joo Shin Jong Youl Lee Eun Bee Choi Hyeong Seok An Kyung-Ah Park Zhen Jin Dong Kun Lee Tamas L. Horvath Gu Seob Roh 《Biochemical and biophysical research communications》2019,508(1):123-129
Hypothalamic inflammation has been known as a contributor to high-fat diet (HFD)-induced insulin resistance and obesity. Myeloid-specific sirtuin 1 (SIRT1) deletion aggravates insulin resistance and hypothalamic inflammation in HFD-fed mice. Neurogranin, a calmodulin-binding protein, is expressed in the hypothalamus. However, the effects of myeloid SIRT1 deletion on hypothalamic neurogranin has not been fully clarified. To investigate the effect of myeloid SIRT1 deletion on food intake and hypothalamic neurogranin expression, mice were fed a HFD for 20 weeks. Myeloid SIRT1 knockout (KO) mice exhibited higher food intake, weight gain, and lower expression of anorexigenic proopiomelanocortin in the arcuate nucleus than WT mice. In particular, KO mice had lower ventromedial hypothalamus (VMH)-specific neurogranin expression. However, SIRT1 deletion reduced HFD-induced hypothalamic neurogranin. Furthermore, hypothalamic phosphorylated AMPK and parvalbumin protein levels were also lower in HFD-fed KO mice than in HFD-fed WT mice. Thus, these findings suggest that myeloid SIRT1 deletion affects food intake through VMH-specific neurogranin-mediated AMPK signaling and hypothalamic inflammation in mice fed a HFD. 相似文献
96.
Han Seungsu Lee Yeongmok Park Eun Joo Min Myung Ki Lee Yongsang Kim Tae-Houn Kim Beom-Gi Lee Sangho 《Plant molecular biology》2019,100(3):319-333
Plant Molecular Biology - We determined the structure of OsPYL/RCAR3:OsPP2C50 complex with pyrabactin. Our results suggest that a less-conserved phenylalanine of OsPYL/RCAR subfamily I is... 相似文献
97.
Jason E. Chung Hannah R. Joo Jiang Lan Fan Daniel F. Liu Alex H. Barnett Supin Chen Charlotte Geaghan-Breiner Mattias P. Karlsson Magnus Karlsson Kye Y. Lee Hexin Liang Jeremy F. Magland Jeanine A. Pebbles Angela C. Tooker Leslie F. Greengard Vanessa M. Tolosa Loren M. Frank 《Neuron》2019,101(1):21-31.e5
98.
99.
100.
A novel method for ab initio prediction of protein tertiary structures, PROFESY (PROFile Enumerating SYstem), is proposed. This method utilizes the secondary structure prediction information of a query sequence and the fragment assembly procedure based on global optimization. Fifteen-residue-long fragment libraries are constructed using the secondary structure prediction method PREDICT, and fragments in these libraries are assembled to generate full-length chains of a query protein. Tertiary structures of 50 to 100 conformations are obtained by minimizing an energy function for proteins, using the conformational space annealing method that enables one to sample diverse low-lying local minima of the energy. We apply PROFESY for benchmark tests to proteins with known structures to demonstrate its feasibility. In addition, we participated in CASP5 and applied PROFESY to four new-fold targets for blind prediction. The results are quite promising, despite the fact that PROFESY was in its early stages of development. In particular, PROFESY successfully provided us the best model-one structure for the target T0161. 相似文献