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Inhibition of Gli/hedgehog signaling in prostate cancer cells by “cancer bush” Sutherlandia frutescens extract
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Two types of reporters for optical sensing of NF-kappaB p50 protein-oligodeoxyribonucleotide (ODN) duplex interactions were designed and compared in vitro. The reporters were based on the effect of fluorescence resonance energy transfer (FRET) between the pair donor Cy5.5 near-infrared (NIR) fluorochrome and either 800CW emitting fluorescence dye acceptor (800CW-Cy), or a nonemitting QSY 21 dye quencher (QSY-Cy). The donor and the acceptor dyes were covalently linked to the complementary oligonucleotides, respectively: Cy dye was conjugated to 3'-thiol, whereas 800CW or QSY21 were conjugated to a hydrophilic internucleoside phosphate amino linker. The reporters were tested initially using recombinant NF-kappaB p50 protein binding assays. Both reporters were binding p50 protein, which protected oligonucleotide duplex from degradation in the presence of exonuclease.The incubation of 800CW-Cy reporter in the presence of control or IL-1beta treated human endothelial cells showed the uptake of the reporter in the cytoplasm and the nucleus. The measurement of NIR fluorescence ratio (i.e. Cy5.5/800CW) showed a partial loss of FRET and the increased Cy5.5 fluorescence in nontreated, control cells. Thus, the specific p50 binding to ODN duplex reporters affected the donor-acceptor fluorochrome pair. NF-kappaB p50 exhibited the protective effect on FRET between NIR fluorochromes linked to the complementary strands of the reporter duplex. 相似文献
57.
Svetlana N. Kovalchuk Irina Yu. Bakunina Viktor I. Emelyanenko Konstantin V. Guzev Valeri A. Rasskazov 《Carbohydrate research》2009,344(2):191-252
An endo-(1→3)-β-d-glucanase (L0) with molecular mass of 37 kDa was purified to homogeneity from the crystalline style of the scallop Chlamys albidus. The endo-(1→3)-β-d-glucanase was extremely thermolabile with a half-life of 10 min at 37 °C. L0 hydrolyzed laminaran with Km ∼ 0.75 mg/mL, and catalyzed effectively transglycosylation reactions with laminaran as donor and p-nitrophenyl β d-glucoside as acceptor (Km ∼ 2 mg/mL for laminaran) and laminaran as donor and as acceptor (Km ∼ 5 mg/mL) yielding p-nitrophenyl β d-glucooligosaccharides (n = 2-6) and high-molecular branching (1→3),(1→6)-β-d-glucans, respectively. Efficiency of hydrolysis and transglycosylation processes depended on the substrate structure and decreased appreciably with the increase of the percentage of β-(1→6)-glycosidic bonds, and laminaran with 10% of β-(1→6)-glycosidic bonds was the optimal substrate for both reactions. The CD spectrum of L0 was characteristic for a protein with prevailing β secondary-structural elements. Binding L0 with d-glucose as the best acceptor for transglycosylation was investigated by the methods of intrinsic tryptophan fluorescence and CD. Glucose in concentration sufficient to saturate the enzyme binding sites resulted in a red shift in the maximum of fluorescence emission of 1-1.5 nm and quenching the Trp fluorescence up to 50%. An apparent association constant of L0 with glucose (Ka = 7.4 × 105 ± 1.1 × 105 M−1) and stoichiometry (n = 13.3 ± 0.7) was calculated. The cDNA encoding L0 was sequenced, and the enzyme was classified in glycoside hydrolases family 16 on the basis of the amino acid sequence similarity. 相似文献
58.
Valeri Pawlowski 《Inorganica chimica acta》2009,362(1):226-228
The compounds Pt(quinap)(CN)2, and [Cu(quinap)I]2 with quinap = 1-(2-diphenylphosphino-1-naphthyl)isoquinoline were synthesized. Quinap is a bidentate ligand which contains a isoquinoline and an arylphosphine group with CT acceptor properties. Accordingly, the Pt(II) and Cu(I) quinap complexes are characterized by a phosphorescence originating from the lowest-energy MLCT triplets with some IL admixture. 相似文献
59.
A model of time-delay recurrently coupled spatially segregated neural assemblies is here proposed. We show that it operates
like some of the hierarchical architectures of the brain. Each assembly is a neural network with no delay in the local couplings
between the units. The delay appears in the long range feedforward and feedback inter-assemblies communications. Bifurcation
analysis of a simple four-units system in the autonomous case shows the richness of the dynamical behaviors in a biophysically
plausible parameter region. We find oscillatory multistability, hysteresis, and stability switches of the rest state provoked
by the time delay. Then we investigate the spatio-temporal patterns of bifurcating periodic solutions by using the symmetric
local Hopf bifurcation theory of delay differential equations and derive the equation describing the flow on the center manifold
that enables us determining the direction of Hopf bifurcations and stability of the bifurcating periodic orbits. We also discuss
computational properties of the system due to the delay when an external drive of the network mimicks external sensory input. 相似文献
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Valeri B. Kozhemyako Galina N. Veremeichik Yuri N. Shkryl Svetlana N. Kovalchuk Vladimir B. Krasokhin Valeri A. Rasskazov Yuri N. Zhuravlev Victor P. Bulgakov Yuri N. Kulchin 《Marine biotechnology (New York, N.Y.)》2010,12(4):403-409
Silicatein genes are known to be involved in siliceous spicule formation in marine sponges. Proteins encoded by these genes,
silicateins, were recently proposed for nanobiotechnological applications. We studied silicatein genes of marine sponges Latrunculia oparinae collected in the west Pacific region, shelf of Kuril Islands. Five silicatein genes, LoSilA1, LoSilA1a, LoSilA2, and LoSilA3 (silicatein-α group), LoSilB (silicatein-β group), and one cathepsin gene, LoCath, were isolated from the sponge L. oparinae for the first time. The deduced amino acid sequence of L. oparinae silicateins showed high-sequence identity with silicateins described previously. LoCath contains the catalytic triad of amino acid residues Cys-His-Asn characteristic for cathepsins as well as motifs typical for
silicateins. A phylogenetic analysis places LoCath between sponge silicateins-β and L-cathepsins suggesting that the LoCath gene represents an intermediate form between silicatein and cathepsin genes. Additionally, we identified, for the first time,
silicatein genes (AcSilA and AcSilB) in nonspicule-forming marine sponge, Acаnthodendrilla sp. The results suggest that silicateins could participate also in the function(s) unrelated to spiculogenesis. 相似文献