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821.
Huang Z Lin L Gao Y Chen Y Yan X Xing J Hang W 《Molecular & cellular proteomics : MCP》2011,10(10):M111.007922
The purpose of this study was to use metabonomic profiling to identify a potential specific biomarker pattern in urine as a noninvasive bladder cancer (BC) detection strategy. A liquid chromatography-mass spectrometry based method, which utilized both reversed phase liquid chromatography and hydrophilic interaction chromatography separations, was performed, followed by multivariate data analysis to discriminate the global urine profiles of 27 BC patients and 32 healthy controls. Data from both columns were combined, and this combination proved to be effective and reliable for partial least squares-discriminant analysis. Following a critical selection criterion, several metabolites showing significant differences in expression levels were detected. Receiver operating characteristic analysis was used for the evaluation of potential biomarkers. Carnitine C9:1 and component I, were combined as a biomarker pattern, with a sensitivity and specificity up to 92.6% and 96.9%, respectively, for all patients and 90.5% and 96.9%, respectively for low-grade BC patients. Metabolic pathways of component I and carnitine C9:1 are discussed. These results indicate that metabonomics is a practicable tool for BC diagnosis given its high efficacy and economization. The combined biomarker pattern showed better performance than single metabolite in discriminating bladder cancer patients, especially low-grade BC patients, from healthy controls. 相似文献
822.
Jeong J Jung Y Na S Jeong J Lee E Kim MS Choi S Shin DH Paek E Lee HY Lee KJ 《Molecular & cellular proteomics : MCP》2011,10(3):M110.000513
Redox-active cysteine, a highly reactive sulfhydryl, is one of the major targets of ROS. Formation of disulfide bonds and other oxidative derivatives of cysteine including sulfenic, sulfinic, and sulfonic acids, regulates the biological function of various proteins. We identified novel low-abundant cysteine modifications in cellular GAPDH purified on 2-dimensional gel electrophoresis (2D-PAGE) by employing selectively excluded mass screening analysis for nano ultraperformance liquid chromatography-electrospray-quadrupole-time of flight tandem mass spectrometry, in conjunction with MODi and MODmap algorithm. We observed unexpected mass shifts (Δm=-16, -34, +64, +87, and +103 Da) at redox-active cysteine residue in cellular GAPDH purified on 2D-PAGE, in oxidized NDP kinase A, peroxiredoxin 6, and in various mitochondrial proteins. Mass differences of -16, -34, and +64 Da are presumed to reflect the conversion of cysteine to serine, dehydroalanine (DHA), and Cys-SO2-SH respectively. To determine the plausible pathways to the formation of these products, we prepared model compounds and examined the hydrolysis and hydration of thiosulfonate (Cys-S-SO2-Cys) either to DHA (Δm=-34 Da) or serine along with Cys-SO2-SH (Δm=+64 Da). We also detected acrylamide adducts of sulfenic and sulfinic acids (+87 and +103 Da). These findings suggest that oxidations take place at redox-active cysteine residues in cellular proteins, with the formation of thiosulfonate, Cys-SO2-SH, and DHA, and conversion of cysteine to serine, in addition to sulfenic, sulfinic and sulfonic acids of reactive cysteine. 相似文献
823.
SAG101 forms a ternary complex with EDS1 and PAD4 and is required for resistance signaling against turnip crinkle virus 总被引:1,自引:0,他引:1
Zhu S Jeong RD Venugopal SC Lapchyk L Navarre D Kachroo A Kachroo P 《PLoS pathogens》2011,7(11):e1002318
EDS1, PAD4, and SAG101 are common regulators of plant immunity against many pathogens. EDS1 interacts with both PAD4 and SAG101 but direct interaction between PAD4 and SAG101 has not been detected, leading to the suggestion that the EDS1-PAD4 and EDS1-SAG101 complexes are distinct. We show that EDS1, PAD4, and SAG101 are present in a single complex in planta. While this complex is preferentially nuclear localized, it can be redirected to the cytoplasm in the presence of an extranuclear form of EDS1. PAD4 and SAG101 can in turn, regulate the subcellular localization of EDS1. We also show that the Arabidopsis genome encodes two functionally redundant isoforms of EDS1, either of which can form ternary complexes with PAD4 and SAG101. Simultaneous mutations in both EDS1 isoforms are essential to abrogate resistance (R) protein-mediated defense against turnip crinkle virus (TCV) as well as avrRps4 expressing Pseudomonas syringae. Interestingly, unlike its function as a PAD4 substitute in bacterial resistance, SAG101 is required for R-mediated resistance to TCV, thus implicating a role for the ternary complex in this defense response. However, only EDS1 is required for HRT-mediated HR to TCV, while only PAD4 is required for SA-dependent induction of HRT. Together, these results suggest that EDS1, PAD4 and SAG101 also perform independent functions in HRT-mediated resistance. 相似文献
824.
The ability to respond to environmental temperature variation is essential for survival in animals. Flies show robust temperature-preference behaviour (TPB) to find optimal temperatures. Recently, we have shown that Drosophila mushroom body (MB) functions as a center controlling TPB. However, neuromodulators that control the TPB in MB remain unknown. To identify the functions of dopamine in TPB, we have conducted various genetic studies in Drosophila. Inhibition of dopamine biosynthesis by genetic mutations or treatment with chemical inhibitors caused flies to prefer temperatures colder than normal. We also found that dopaminergic neurons are involved in TPB regulation, as the targeted inactivation of dopaminergic neurons by expression of a potassium channel (Kir2.1) induced flies with the loss of cold avoidance. Consistently, the mutant flies for dopamine receptor gene (DopR) also showed a cold temperature preference, which was rescued by MB-specific expression of DopR. Based on these results, we concluded that dopamine in MB is a key component in the homeostatic temperature control of Drosophila. The current findings will provide important bases to understand the logic of thermosensation and temperature preference decision in Drosophila. 相似文献
825.
Raghwani J Rambaut A Holmes EC Hang VT Hien TT Farrar J Wills B Lennon NJ Birren BW Henn MR Simmons CP 《PLoS pathogens》2011,7(6):e1002064
Dengue is one of the most important infectious diseases of humans and has spread throughout much of the tropical and subtropical world. Despite this widespread dispersal, the determinants of dengue transmission in endemic populations are not well understood, although essential for virus control. To address this issue we performed a phylogeographic analysis of 751 complete genome sequences of dengue 1 virus (DENV-1) sampled from both rural (Dong Thap) and urban (Ho Chi Minh City) populations in southern Viet Nam during the period 2003-2008. We show that DENV-1 in Viet Nam exhibits strong spatial clustering, with likely importation from Cambodia on multiple occasions. Notably, multiple lineages of DENV-1 co-circulated in Ho Chi Minh City. That these lineages emerged at approximately the same time and dispersed over similar spatial regions suggests that they are of broadly equivalent fitness. We also observed an important relationship between the density of the human host population and the dispersion rate of dengue, such that DENV-1 tends to move from urban to rural populations, and that densely populated regions within Ho Chi Minh City act as major transmission foci. Despite these fluid dynamics, the dispersion rates of DENV-1 are relatively low, particularly in Ho Chi Minh City where the virus moves less than an average of 20 km/year. These low rates suggest a major role for mosquito-mediated dispersal, such that DENV-1 does not need to move great distances to infect a new host when there are abundant susceptibles, and imply that control measures should be directed toward the most densely populated urban environments. 相似文献
826.
Myostatin (MSTN) is a potent negative regulator of skeletal muscle growth in mammalian species, and its activity is inhibited
by MSTN prodomain, the N-terminal part of proMSTN cleaved during post-translational MSTN processing. In fish, MSTN also appears
to suppress fish muscle growth with its activity being inhibited by prodomain. The objective of this study was to produce
bioactive MSTN-1 prodomain of rockfish (S. schlegeli), a commercial aquaculture species in East Asia, in E. coli using maltose binding protein (MBP) as a fusion partner. Rockfish MSTN-1 prodomain (sMSTN1pro) cDNA was cloned into the pMALc2x
vector, and proteins (MBP-sMSTN1pro) were expressed in Rosetta-gami 2(DE3)pLysS cells by IPTG induction. The MBP-sMSTN1pro
was expressed in soluble forms, and affinity purified using amylose resin. The affinity purified MBP-sMSTN1pro suppressed
MSTN activity in vitro. The results suggest that MBP is probably a useful fusion partner in producing bioactive MSTN prodomains
of various animal species in E. coli. 相似文献
827.
Lee KJ Jeong CS An YJ Lee HJ Park SJ Seok YJ Kim P Lee JH Lee KH Cha SS 《Nature chemical biology》2011,7(7):434-436
The interaction between fermentation-respiration switch (FrsA) protein and glucose-specific enzyme IIA(Glc) increases glucose fermentation under oxygen-limited conditions. We show that FrsA converts pyruvate to acetaldehyde and carbon dioxide in a cofactor-independent manner and that its pyruvate decarboxylation activity is enhanced by the dephosphorylated form of IIA(Glc) (d-IIA(Glc)). Crystal structures of FrsA and its complex with d-IIA(Glc) revealed residues required for catalysis as well as the structural basis for the activation by d-IIA(Glc). 相似文献
828.
Lee K Kim H Kim JM Kim JR Kim KJ Kim YJ Park SI Jeong JH Moon YM Lim HS Bae DW Kwon J Ko CY Kim HS Shin HI Jeong D 《Journal of cellular and molecular medicine》2011,15(10):2082-2094
Systemic transplantation of adipose-derived stem cells (ASCs) is emerging as a novel therapeutic option for functional recovery of diverse damaged tissues. This study investigated the effects of systemic transplantation of human ASCs (hASCs) on bone repair. We found that hASCs secrete various bone cell-activating factors, including hepatocyte growth factor and extracellular matrix proteins. Systemic transplantation of hASCs into ovariectomized mice induced an increased number of both osteoblasts and osteoclasts in bone tissue and thereby prevented bone loss. We also observed that conditioned medium from hASCs is capable of stimulating proliferation and differentiation of osteoblasts via Smad/extracellular signal-regulated kinase (ERK)/JNK (c-jun NH(2) -terminal kinase) activation as well as survival and differentiation of osteoclasts via ERK/JNK/p38 activation in vitro. Overall, our findings suggest that paracrine factors secreted from hASCs improve bone repair and that hASCs can be a valuable tool for use in osteoporosis therapy. 相似文献
829.
Miriam Kunze Sangsik Jeong Elie Paillard Monika Schönhoff Martin Winter Stefano Passerini 《Liver Transplantation》2011,1(2):274-281
Some cations of ionic liquids (ILs) of interest for high‐energy electrochemical storage devices, such as lithium batteries and supercapacitors, have a structure similar to that of surfactants. For such, it is very important to understand if these IL cations tend to aggregate like surfactants since this would affect the ion mobility and thus the ionic conductivity. The aggregation behaviour of ILs consisting of the bis(trifluoromethanesulfonyl)imide anion and different N‐alkyl‐N‐methyl‐pyrrolidinium cations, with the alkyl chain varied from C3H7 to C8H17, was extensively studied with NMR and Raman methods, also in the presence of Li+ cations. 2H NMR spin‐lattice and spin‐spin relaxation rates were analyzed by applying the “two step” model of surfactant dynamics. Here we show that, indeed, the cations in these ILs tend to form aggregates surrounded by the anions. The effect is even more pronounced in the presence of dissolved lithium cations. 相似文献
830.