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991.
992.
993.
Sohn EJ Kim DW Kim YN Kim SM Lim SS Kang TC Kwon HY Kim DS Cho SW Han KH Park J Eum WS Hwang HS Choi SY 《Biochemical and biophysical research communications》2011,(3):336-340
The low transduction efficiency of various proteins is an obstacle to their therapeutic application. However, protein transduction domains (PTDs) are well-known for a highly effective tool for exogenous protein delivery to cells. We examined the effects of pergolide mesylate (PM) on the transduction of PEP-1-catalase into HaCaT human keratinocytes and mice skin and on the anti-inflammatory activity of PEP-1-catatase against 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation using Western blot and histological analysis. PM enhanced the time- and dose-dependent transduction of PEP-1-catalase into HaCaT cells without affecting the cellular toxicity. In a mouse edema model, PEP-1-catalase inhibited the increased expressions of inflammatory mediators and cytokines such as cyclooxygenase-2, inducible nitric oxide synthase, interleukin-6 and -1β, and tumor necrosis factor-α induced by TPA. On the other hand, PM alone failed to exert any significant anti-inflammatory effects. However, the anti-inflammatory effect of co-treatment with PEP-1-catalase and PM was more potent than that of PEP-1-catalase alone. Our results indicate that PM may enhance the delivery of PTDs fusion therapeutic proteins to target cells and tissues and has potential to increase their therapeutic effects of such drugs against various diseases. 相似文献
994.
Insun Hwang Danbee Ha Ginnae Ahn Eunjin Park Haejin Joo Youngheun Jee 《Biochemical and biophysical research communications》2011,(2):464
Recently emerging evidence that the NF-κB family plays an important role in autoimmune disease has produced very broad and sometimes paradoxical conclusions. In the present study, we elucidated that the activation of RelA (p65) of NF-κB and IκB dissociation assumes a distinct role in experimental autoimmune encephalomyelitis (EAE) progression by altering IκB phosphorylation and/or degradation. In the present study of factors that govern EAE, the presence and immunoreactivity of nuclear RelA and phospho-IκB were recorded at the initiation and peak stage, and degradation of IκBα progressed rapidly at an early stage then stabilized during recovery. The immunoreactivity to RelA and phospho-IκB occurred mainly in inflammatory cells and microglial cells but only slightly in astrocytes. Subsequently, the blockade of IκB dissociation from NF-κB reduced the severity of disease by decreasing antigen-specific T cell response and production of IL-17 in EAE. Thus, blocking the dissociation of IκB from NF-κB can be utilized as a strategy to inhibit the NF-κB signal pathway thereby to reduce the initiation, progression, and severity of EAE. 相似文献
995.
Shin YS Remacle F Fan R Hwang K Wei W Ahmad H Levine RD Heath JR 《Biophysical journal》2011,(10):2378-2386
Protein signaling networks among cells play critical roles in a host of pathophysiological processes, from inflammation to tumorigenesis. We report on an approach that integrates microfluidic cell handling, in situ protein secretion profiling, and information theory to determine an extracellular protein-signaling network and the role of perturbations. We assayed 12 proteins secreted from human macrophages that were subjected to lipopolysaccharide challenge, which emulates the macrophage-based innate immune responses against Gram-negative bacteria. We characterize the fluctuations in protein secretion of single cells, and of small cell colonies (n = 2, 3,···), as a function of colony size. Measuring the fluctuations permits a validation of the conditions required for the application of a quantitative version of the Le Chatelier's principle, as derived using information theory. This principle provides a quantitative prediction of the role of perturbations and allows a characterization of a protein-protein interaction network. 相似文献
996.
Polo-like kinase-1 (Plk1) is essential for progression of mitosis and localizes to centrosomes, central spindles, midbody, and kinetochore. Ran, a small GTPase of the Ras superfamily, plays a role in microtubule dynamics and chromosome segregation during mitosis. Although Ran-binding protein-1 (RanBP1) has been reported as a regulator of RanGTPase for its mitotic functions, the action mechanism between Ran and RanBP1 during mitosis is still unknown. Here, we demonstrated in vitro and in vivo phosphorylation of RanBP1 by Plk1 as well as the importance of phosphorylation of RanBP1 in the interaction between Plk1 and Ran during early mitosis. Both phosphorylation-defective and N-terminal deletion mutant constructs of RanBP1 disrupted the interaction with Ran, and depletion of Plk1 also disrupted the formation of a complex between Ran and RanBP1. In addition, the results from both ectopic expression of phosphorylation-defective mutant construct and a functional complementation on RanBP1 deficiency with this mutant indicated that phosphorylation of RanBP1 by Plk1 might be crucial to microtubule nucleation and spindle assembly during mitosis. 相似文献
997.
Helwig M Lee SN Hwang JR Ozawa A Medrano JF Lindberg I 《The Journal of biological chemistry》2011,286(49):42504-42513
The small neuroendocrine protein 7B2 is required for the production of active prohormone convertase 2 (PC2), an enzyme involved in the synthesis of peptide hormones, such as glucagon and proopiomelanocortin-derived α-melanocyte-stimulating hormone. However, whether 7B2 can dynamically modulate peptide production through regulation of PC2 activity remains unclear. Infection of the pancreatic alpha cell line α-TC6 with 7B2-encoding adenovirus efficiently increased production of glucagon, whereas siRNA-mediated knockdown of 7B2 significantly decreased stored glucagon. Furthermore, rescue of 7B2 expression in primary pituitary cultures prepared from 7B2 null mice restored melanocyte-stimulating hormone production, substantiating the role of 7B2 as a regulatory factor in peptide biosynthesis. In anterior pituitary and pancreatic beta cell lines, however, overexpression of 7B2 affected neither production nor secretion of peptides despite increased release of active PC2. In direct contrast, 7B2 overexpression decreased the secretion and increased the activity of PC2 within α-TC6 cells; the increased intracellular concentration of active PC2 within these cells may therefore account for the enhanced production of glucagon. In line with these findings, we found elevated circulating glucagon levels in 7B2-overexpressing cast/cast mice in vivo. Surprisingly, when proopiomelanocortin and proglucagon were co-expressed in either pituitary or pancreatic alpha cell lines, proglucagon processing was preferentially decreased when 7B2 was knocked down. Taken together, these results suggest that proglucagon cleavage has a greater dependence on PC2 activity than other precursors and moreover that 7B2-dependent routing of PC2 to secretory granules is cell line-specific. The manipulation of 7B2 could therefore represent an effective way to selectively regulate synthesis of certain PC2-dependent peptides. 相似文献
998.
Differential tolerance of congeners with an overlapping ecological niche, to the anthropogenic activities leads to a faunal
shift at spatiotemporal scales, which in turn provides an insight to the subtle changes happening in the abiotic environment.
Aiming to asses the effects of influent and effluent waters of two Nuclear Power Plants (NPP-I and NPP-II), of northern Taiwan
this study monitored the biography and population trajectories of two congeners of calanoid copepod, Temora discaudata and Temora turbinata from September, 1998 to April, 2009, comprising 44 sampling cruises in the southern East China Sea. The two Temora species occurred in >90% of the samples, showing differential trends of occurrence and abundance. The density of T. turbinata was higher than T. discaudata. The absolute and relative abundance of both of the Temora spp. increased significantly from inlet and outlet stations to seaward stations 500–1000 m away from land, beyond which there
was a decline in density. The effects of month, season, year on abundance and occurrence of either Temora species were highly significant. The maximum and minimum abundance of T. discaudata was recorded in Aug, 1999 and March, 2000, respectively, where as those of T. turbinata was recorded in May, 2000 and March, 2000. The density, and occurrence frequency of either species showed a positive correlation
with seawater temperature, but neither species showed a significant correlation with salinity. The areas around inlet and
outlet stations record lower copepod density than unaffected stations. Our results point to a faunal shift within the congeners
in coastal waters in the vicinity of both the NPPs. These results will be useful in assessing the ecological impact of discharge
from NPPs, and in understanding the long-term population dynamics of Temora spp. which are believed to be invasive and cosmopolitan. 相似文献
999.
Jae-Seong Lee Ryeo-Ok Kim Jae-Sung Rhee Jeonghoon Han Dae-Sik Hwang Beom-Soon Choi Chang Joo Lee Yong-Dal Yoon Jong-Sung Lim Young-Mi Lee Gyung Soo Park Atsushi Hagiwara Ik-Young Choi 《Hydrobiologia》2011,662(1):65-75
The monogonont rotifer, Brachionus ibericus (S type), is considered to be a promising model species for developmental biology, evolution, and environmental genomics. In an attempt to accelerate the molecular understanding of B. ibericus, we sequenced 680.5 Mb of genomic DNA using the genome sequencer GS-FLX-Titanium. We obtained 2,062,621 reads (average read length 329.9 bp) and 145,418 contigs (total contigs length 125.7 Mb) after excluding small reads (less than 200 bp) from the assembly, and finally obtained 10,133 unigenes (E value ?? 9.00E?04) after non-redundant (NR) BLAST search. In this article, we summarize the genomic DNA sequences of B. ibericus and discuss their potential use in the study of reproductive biology, endocrinology, environmental genomics, and ecotoxicological studies, and for providing insight into the genetic basis of mechanisms such as egg formation, antioxidant stress defense, and xenobiotic metabolism. 相似文献
1000.