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151.
Kolundžić N Bojić-Trbojević Ž Kovačević T Stefanoska I Kadoya T Vićovac L 《PloS one》2011,6(12):e28514
Background
Interactions of glycoconjugates with endogenous galectins, have been long proposed to participate in several reproductive processes including implantation. In human placenta gal-1, gal-3, gal-8, and gal-13 proteins are known to be present. Each of them has been proposed to play multiple functions, but so far no clear picture has emerged. We hypothesized that gal-1 participates in trophoblast invasion, and conducted Matrigel invasion assay using isolated cytotrophoblast from first trimester placenta and HTR-8/SVneo cell line to test it.Methods and Findings
Function blocking anti-gal-1 antibody was employed to assess participation of endogenous gal-1 in cell adhesion, cell invasion of HTR-8/SVneo cells. When gal-1 was blocked in isolated trophoblast cell invasion was reduced to 75% of control (SEM±6.3, P<0.001) and to 66% of control (SEM±1.7, P<0.001) in HTR-8/SVneo cell line. Increased availability of gal-1, as two molecular forms of recombinant human gal-1 (CS-gal-1 and Ox-gal-1), resulted in increased cell invasion by cytotrophoblast to 151% (SEM±16, P<0.01) with 1 ng/ml of CS-gal-1, and to 192% (SEM±51, P<0.05) with 1 µg/ml of Ox-gal-1. Stimulation was also observed in HTR-8/SVneo cells, to 317% (SEM±58, P<0.001) by CS-gal-1, and to 200% (SEM±24, P<0.001) by Ox-gal-1 at 1 µg/ml. Both sets of results confirmed involvement of gal-1 in trophoblast invasion. Galectin profile of isolated cytotrophoblast and HTR-8/SVneo cells was established using RT-PCR and real-time PCR and found to consist of gal-1, gal-3 and gal-8 for both cell types. Only gal-1 was located at the trophoblast cell membrane, as determined by FACS analysis, which is consistent with the results of the functional tests.Conclusion and Significance
These findings qualify gal-1 as a member of human trophoblast cell invasion machinery. 相似文献152.
Jerneja Ambrožič Avguštin Darja Žgur Bertok Rok Kostanjšek Gorazd Avguštin 《Antonie van Leeuwenhoek》2013,103(4):763-769
A bacterial strain designated JA-1, related to Janthinobacterium lividum, was isolated from glacier ice samples from the island Spitsbergen in the Arctic. The strain was tested for phenotypic traits and the most prominent appeared to be the dark red brown to black pigmentation different from the violet pigment of Janthinobacterium, Chromobacterium and Iodobacter. Phylogenetic analysis based on 16S rRNA gene sequences and DNA–DNA hybridization tests showed that strain JA-1 belongs to the genus Janthinobacterium but represents a novel lineage distinct from the two known species of this genus, J. lividum and Janthinobacterium agaricidamnosum. The DNA G + C content of strain JA-1 was determined to be 62.3 mol %. The isolate is a psychrotrophic Gram negative bacterium, rod-shaped with rounded ends, containing intracellular inclusions and one polar flagellum. On the basis of the presented results strain JA-1 is proposed as the type strain of a novel species of the genus Janthinobacterium, for which the name Janthinobacterium svalbardensis sp. nov. is proposed (JA-1T = DSM 25734, ZIM B637). 相似文献
153.
Jelena Dragišić Maksimović Jingyi Zhang Fanrong Zeng Branka D. Živanović Lana Shabala Meixue Zhou Sergey Shabala 《Plant and Soil》2013,365(1-2):141-155
Aims
A causal relationship between salinity and oxidative stress tolerance and a suitability of using root antioxidant activity as a biochemical marker for salinity tolerance in barley was investigated.Methods
Net ion fluxes were measured from the mature zone of excised roots of two barley varieties contrasting in their salinity tolerance using non-invasive MIFE technique in response to acute and prolonged salinity treatment. These changes were correlated with activity of major antioxidant enzymes; ascorbate peroxidase, catalase, and superoxide dismutase.Results
It was found that genotypic difference in salinity tolerance was largely independent of root integrity, and observed not only for short-term but also long-term NaCl exposures. Higher K+ retention ability (and, hence, salinity tolerance) positively correlated with oxidative stress tolerance. At the same time, antioxidant activities were constitutively higher in a sensitive but not tolerant variety, and no correlation was found between SOD activity and salinity tolerance index during large-scale screening.Conclusion
Although salinity tolerance in barley correlates with its oxidative stress tolerance, higher antioxidant activity at one particular time does not correlate with salinity tolerance and, as such, cannot be used as a biochemical marker in barley screening programs. 相似文献154.
Edita Janková Drdová Lukáš Synek Tamara Pečenková Michal Hála Ivan Kulich John E. Fowler Angus S. Murphy Viktor Žárský 《The Plant journal : for cell and molecular biology》2013,73(5):709-719
In land plants polar auxin transport is one of the substantial processes guiding whole plant polarity and morphogenesis. Directional auxin fluxes are mediated by PIN auxin efflux carriers, polarly localized at the plasma membrane. The polarization of exocytosis in yeast and animals is assisted by the exocyst: an octameric vesicle‐tethering complex and an effector of Rab and Rho GTPases. Here we show that rootward polar auxin transport is compromised in roots of Arabidopsis thaliana loss‐of‐function mutants in the EXO70A1 exocyst subunit. The recycling of PIN1 and PIN2 proteins from brefeldin–A compartments is delayed after the brefeldin‐A washout in exo70A1 and sec8 exocyst mutants. Relocalization of PIN1 and PIN2 proteins after prolonged brefeldin‐A treatment is largely impaired in these mutants. At the same time, however, plasma membrane localization of GFP:EXO70A1, and the other exocyst subunits studied (GFP:SEC8 and YFP:SEC10), is resistant to brefeldin‐A treatment. In root cells of the exo70A1 mutant, a portion of PIN2 is internalized and retained in specific, abnormally enlarged, endomembrane compartments that are distinct from VHA‐a1‐labelled early endosomes or the trans‐Golgi network, but are RAB‐A5d positive. We conclude that the exocyst is involved in PIN1 and PIN2 recycling, and thus in polar auxin transport regulation. 相似文献
155.
Free radicals mediated damage of phospholipids, proteins and nucleic acids results in subsequent neuronal degeneration and
cell loss. Aim of this study was to evaluate the existence of lipid and protein oxidative damage and the activities of superoxide
dismutase (SOD) and glutathione peroxidase (GSH-Px) in various rat brain structures 24 h after lateral fluid percussion brain
injury (LFPI). Parietal cortex, hippocampus, thalamus, entorhinal cortex, and cerebellum from the ipsilateral hemisphere were
processed for analyses of the thiobarbituric acid reactive substances (TBARS) and oxidized protein levels as well as for the
SOD and GSH-Px activities. Immunohistochemical detection of oxidized proteins was also performed. Results of our study showed
that LFPI caused significant oxidative stress in the parietal cortex and hippocampus while other brain regions tested in this
study were not oxidatively altered by LFPI. GSH-Px activities were significantly increased in the parietal cortex and hippocampus,
while the SOD activities remained unchanged following LFPI in all regions investigated. 相似文献
156.
Nováček J Zawadzka-Kazimierczuk A Papoušková V Zídek L Sanderová H Krásný L Koźmiński W Sklenář V 《Journal of biomolecular NMR》2011,50(1):1-11
Two novel 5D NMR experiments (CACONCACO, NCOCANCO) for backbone assignment of disordered proteins are presented. The pulse
sequences exploit relaxation properties of the unstructured proteins and combine the advantages of 13C-direct detection, non-uniform sampling, and longitudinal relaxation optimization to maximize the achievable resolution and
minimize the experimental time. The pulse sequences were successfully tested on the sample of partially disordered delta subunit
from RNA polymerase from Bacillus subtilis. The unstructured part of this 20 kDa protein consists of 81 amino acids with frequent sequential repeats. A collection of
0.0003% of the data needed for a conventional experiment with linear sampling was sufficient to perform an unambiguous assignment
of the disordered part of the protein from a single 5D spectrum. 相似文献
157.
Grbavčić S Bezbradica D Izrael-Živković L Avramović N Milosavić N Karadžić I Knežević-Jugović Z 《Bioresource technology》2011,102(24):11226-11233
An indigenous Pseudomonas aeruginosa strain has been studied for lipase and protease activities for their potential application in detergents. Produced enzymes were investigated in order to assess their compatibility with several surfactants, oxidizing agents and commercial detergents. The crude lipase appeared to retain high activity and stability in the presence of several surfactants and oxidizing agents and it was insusceptible to proteolysis. Lutensol? XP80 and Triton? X-100 strongly activated the lipase for a long period (up to 40 and 30% against the control after 1h) while the protease activity was enhanced by the addition of Triton? WR1339 and Tween? 80. The washing performance of the investigated surfactants was significantly improved with the addition of the crude enzyme preparation. Studies were further undertaken to improve enzymes production. The optimization of fermentation conditions led to an 8-fold increase of lipase production, while the production of protease was enhanced by 60%. 相似文献
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