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221.
222.
Ubiquitin-conjugating enzymes (UBE2s or E2s) are characterized by the presence of a highly conserved ubiquitin-conjugating (UBC) domain, which predominantly determines the type of ubiquitin chains and directly controls the cellular fate of the substrate. In this study, an E2 homolog was identified and functionally characterized in abalone, which we named ab-UBE2D. The full-length cDNA consists of 1005 bp with an ORF encoding a protein of 147 amino acids. The deduced amino acid sequence shows ab-UBE2D shares conserved UBC domain with other E2 proteins and belongs to class I E2 enzyme family, which are further confirmed by phylogenetic tree analysis. Real-time PCR and western blot analyses showed that ab-UBE2D was ubiquitously expressed in abalone and the expression level of ab-UBE2d was significantly induced by LPS and Poly (I:C). Immunofluorescence microscopy staining demonstrated that native ab-UBE2D was mainly distributed in the cytoplast. Ubiquitination assay showed that ab-UBE2D had ubiquitin conjugating activity to form the enzyme-(Ub)n conjugates. Taken together, these results strongly suggest that ab-UBE2D is an E2 homolog and it may be involved in the immune response of abalone, Haliotis diversicolor supertexta. 相似文献
223.
Zilan Lv Dandan Yang Jie Li Min Hu Min Luo Xiaoqin Zhan Peipei Song Chen Liu Huili Bai Baolin Li Yang Yang Yingying Chen Qiong Shi Yaguang Weng 《Molecules and cells》2013,36(2):119-126
Transforming growth factor-β (TGF-β) is known to promote tumor migration and invasion. Bone morphogenetic proteins (BMPs) are members of the TGF-β family expressed in a variety of human carcinoma cell lines. The role of bone morphogenetic protein 9 (BMP9), the most powerful osteogenic factor, in osteosarcoma (OS) progression has not been fully clarified. The expression of BMP9 and its receptors in OS cell lines was analyzed by RT-PCR. We found that BMP9 and its receptors were expressed in OS cell lines. We further investigated the influence of BMP9 on the biological behaviors of OS cells. BMP9 overexpression in the OS cell lines 143B and MG63 inhibited in vitro cell migration and invasion. We further investigated the expression of a panel of cancer-related genes and found that BMP9 overexpression increased the phosphorylation of Smad1/5/8 proteins, increased the expression of ID1, and reduced the expression and activity of matrix metalloproteinase 9 (MMP9) in OS cells. BMP9 silencing induced the opposite effects. We also found that BMP9 may not affect the chemokine (C-X-C motif) ligand 12 (CXCL12)/C-X-C chemokine receptor type 4 (CXCR4) axis to regulate the invasiveness and metastatic capacity of OS cells. Interestingly, CXCR4 was expressed in both 143B and MG63 cells, while CXCL12 was only detected in MG63 cells. Taken together, we hypothesize that BMP9 inhibits the migration and invasiveness of OS cells through a Smad-dependent pathway by downregulating the expression and activity of MMP9. 相似文献
224.
Jianghong Luo Hui Liu Taoying Zhou Benguo Gu Xuehui Huang Yingying Shangguan Jingjie Zhu Yan Li Yan Zhao Yongchun Wang Qiang Zhao Ahong Wang Ziqun Wang Tao Sang Zixuan Wang Bin Han 《The Plant cell》2013,25(9):3360-3376
Long awns are important for seed dispersal in wild rice (Oryza rufipogon), but are absent in cultivated rice (Oryza sativa). The genetic mechanism involved in loss-of-awn in cultivated rice remains unknown. We report here the molecular cloning of a major quantitative trait locus, An-1, which regulates long awn formation in O. rufipogon. An-1 encodes a basic helix-loop-helix protein, which regulates cell division. The nearly-isogenic line (NIL-An-1) carrying a wild allele An-1 in the genetic background of the awnless indica Guangluai4 produces long awns and longer grains, but significantly fewer grains per panicle compared with Guangluai4. Transgenic studies confirmed that An-1 positively regulates awn elongation, but negatively regulates grain number per panicle. Genetic variations in the An-1 locus were found to be associated with awn loss in cultivated rice. Population genetic analysis of wild and cultivated rice showed a significant reduction in nucleotide diversity of the An-1 locus in rice cultivars, suggesting that the An-1 locus was a major target for artificial selection. Thus, we propose that awn loss was favored and strongly selected by humans, as genetic variations at the An-1 locus that cause awn loss would increase grain numbers and subsequently improve grain yield in cultivated rice. 相似文献
225.
Dr Christos A. Kontogiorgis Yanan Xu Dimitra Hadjipavlou-Litina Yuan Luo 《Free radical research》2013,47(10):1168-1180
The role of oxidative stress and free radicals in the development of Alzheimer's disease (AD) has been the focus of many recent studies. The role of hydrogen peroxide (H2O2) in AD is thought to be associated with Aβ (amyloid – β) damage in cells. A number of coumarin derivatives were previously found to be potent anti-inflammatory and antioxidant agents. Herein, these coumarin derivatives were tested as H2O2 scavengers with the DCF assay using two types of neuronal cells: (a) wild type (N2a) neuroblastoma cells and (b) APP/PS1 transgenic cell line expressing Aβ. Their scavenging activity was varied between the types of cell cultures and it was found to be concentration and time dependent in the mutant cells. Their protective role against cell death further supports this notion. These results suggest that these compounds could be used as a template in the design of new molecules with a possible role in AD. 相似文献
226.
Zheng Guoshou Zhan Chengye Li Zhihui Luo Jinlong 《Cell biochemistry and biophysics》2013,66(2):365-369
The objective of this study is to observe the effects of high dose of anisodamine in the respiratory function of patients with acute lung injury (ALI) induced by trauma. Fifty cases of patients with complicated ALI after trauma were randomly divided into the anisodamine treatment group (n = 26) and the conventional treatment group (n = 24). Intravenous injection of high dose of anisodamine was administrated in the anisodamine treatment group on the basis of conventional treatment. Acute lung injury scores, oxygenation index, PaO2, respiratory mechanic index, mechanical ventilation time, and the occurrence of adverse reactions in the two groups were observed. Acute lung injury scores and respiratory parameters were all significantly improved in the two groups of patients after the treatment (P < 0.05); compared with the conventional treatment group, the improvements of respiratory function in the anisodamine treatment group were more obvious (P < 0.05), the mechanical ventilation time was shorter (P < 0.05), and there was no significant adverse reaction. In conclusion, high dose of anisodamine contributed to improve the respiratory function of the patients with traumatic ALI. 相似文献
227.
Industrial production can produce large amounts of harmful by-products, causing serious pollution and ecological risk. In addition, if government regulations are subjected into the industries, huge cost risk will be faced. This article adopts a two-stage slack-based undesirable-output data envelope analysis (DEA) model to measure the eco-efficiency of China. In the first stage, we analyze the eco-efficiency of each province of China, and in the second stage, we employed a truncated bootstrap method to understand the determinants of eco-efficiency. The results indicate that whereas the eco-efficiency of the eastern region was the highest, that of the western region was the lowest. The western region's economy lagged behind that of other regions, and its environment suffered from heavy pollution. It was found that the level of industrialization did not contribute to eco-efficiency. However, promotion of the service industry, investment for the environment, and regional innovation have positive effects on eco-efficiency. 相似文献
228.
Yi Luo Min Wang Zhonghua Pang Fengtao Jiang Jiangning Chen Junfeng Zhang 《The journal of gene medicine》2013,15(11-12):441-452
229.
We investigated the morphology, morphogenesis and small subunit rRNA gene-based phylogeny of three marine urostylids, Uncinata gigantea Bullington, 1940, Holosticha heterofoissneri Hu & Song, 2001, and Holosticha cf. heterofoissneri. The dorsal morphogenesis of Uncinata gigantea shows de novo formation of two groups of anlagen near the marginal rows. Holosticha cf. heterofoissneri demonstrates fragmentation of the first dorsal kinety anlage as in Holosticha heterofoissneri. Our population of H. heterofoissneri corresponds well with previously described populations in terms of its general morphology and ciliary pattern. Uncinata gigantea can be recognized by its large and highly contractile body, yellowish to brownish cell colour, two types of cortical granules, and 20–30 transversely oriented and densely arranged cirri in the left marginal row, which often overlie the buccal vertex. Based on the new data, especially infraciliature, the genus Uncinata is here redefined. Both the morphology and phylogenetic analyses suggest that the genus Uncinata should be classified within the family Urostylidae. In addition, both morphological and morphogenetic data suggest that Holosticha bradburyae Gong et al., 2001 should be transferred to Uncinata as U. bradburyae (Gong et al., 2001) comb. nov., due to its possession of a characteristically prominent beak-like, leftwards curved projection and the developmental mode of the dorsal kineties. This assignment is supported by the phylogenetic analyses, which placed Uncinata gigantea in a clade with U. bradburyae (Gong et al., 2001) comb. nov., and revealed only 1.13% (19 bp) difference in their SSU-rDNA gene sequence. 相似文献
230.
Tai-Shun Lin Xin Guo Mei-Zhen Luo Mao-Chin Liu Yong-Lian Zhu Ginger E. Dutschman 《Nucleosides, nucleotides & nucleic acids》2013,32(3-5):619-625
Abstract The pharmacokinetics and toxicology of 2′,3′-dideoxy-β-L-5-fluorocytidine (β-L-FddC) and 2′,3′-dideoxy-β-L-cytidine (β-L-ddC) in mice was investigated. In addition, 2′,3′-dideoxy-β-L-5-azacytidine (β-L-5-aza-ddC) and its α-L-anomer (α-L-5-aza-ddC) were synthesized by coupling the silylated 5-azacytosine derivative with 1-O-acetyl-5-O-(tert-butyldimethylsilyl)-2,3-dideoxy-L-ribofuranose, followed by separation of the α-and β-anomers and were evaluated in vitro against HBV and HIV. β-L-5-aza-ddC was found to show significant anti-HBV activity at approximately the same level as 2′,3′-dideoxy-β-D-cytidine (ddC), which is a known anti-HBV agent. β-L-5-aza-ddC was not cytotoxic to L1210, P388, S-180, and CCRF-CEM cells up to a concentration of 100 μ. Conversely, the α-L-anomer was not active against HBV at the same concentration. 相似文献