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51.
Nassa G Tarallo R Ambrosino C Bamundo A Ferraro L Paris O Ravo M Guzzi PH Cannataro M Baumann M Nyman TA Nola E Weisz A 《Proteomics》2011,11(1):159-165
Estrogen receptors α (ER-α) and β (ER-β) play distinct biological roles in onset and progression of hormone-responsive breast cancer, with ER-β exerting a modulatory activity on ER-α-mediated estrogen signaling and stimulation of cell proliferation by mechanisms still not fully understood. We stably expressed human ER-β fused to a tandem affinity purification-tag in estrogen-responsive MCF-7 cells and applied tandem affinity purification and nanoLC-MS/MS to identify the ER-β interactome of this cell type. Functional annotation by bioinformatics analyses of the 303 proteins that co-purify with ER-β from nuclear extracts identify several new molecular partners of this receptor subtype that represents nodal points of a large protein network controlling multiple processes and functions in breast cancer cells. 相似文献
52.
Concetta Fiore Javier Arrizon Anne Gschaedler Javier Flores Patrizia Romano 《World journal of microbiology & biotechnology》2005,21(6-7):1141-1147
Summary In Mexico there are different alcoholic beverages produced from agave juices from different agave plants, which are cooked,
fermented and distilled. For tequila production only Agave tequilana is allowed. In this study we compared yeast strains of different species from different origin (agave and grape juice) for
parameters of technological interest, such as SO2 and copper resistance, ethanol tolerance and enzymatic activities. All agave strains were found to be more resistant to SO2 and agave non-Saccharomyces yeasts were more tolerant to ethanol, whereas grape strains exhibited positive results for β-glucosidase and β-xylosidase activities. As regards fermentations of Agave tequilana juice with ethanol added at different concentrations, only agave Saccharomyces strains were more tolerant to ethanol than grape strains. 相似文献
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54.
Calabrò C Albanese MP Lauriano ER Martella S Licata A 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》2005,43(1):51-56
Histochemical and immunohistochemical study was carried out on nitrinergic innervation and neuroendocrine system in the gill epithelium of the abyssal fish Coelorhynchus coelorhynchus. The results showed that nNOS-positive nerve fibers, originating from the branchial arch were present in the subepithelial tissue of branchial primary filament. nNOS-positive neuroendocrine cells were also present in the primary filaments and secondary lamellae. Numerous mucous cells in the gill epithelium were AB/PAS-positive, while sialic acid was absent as confirmed by neuraminidase reaction and WGA lectin histochemistry. The mucus compounds in abyssal teleost fish are different from those found in pelagic species, being related to their living conditions. In abyssal species, greater numbers of chloride and neuroendocrine cells are involved in the movement of water and electrolytes. Neuroendocrine cells possess oxygen receptors which mediate the cardiovascular and ventilatory response to oxygen deficiency, as reported in teleost species. Besides, NO contributes through nervous stimulation to the regulation of vascular tone and blood circulation in the gill. 相似文献
55.
Biological visual systems are extraordinarily capable of recovering the shape and brightness of objects from sparse and fragmentary information. Using functional magnetic imaging, we show that two associative areas of the dorsal pathway--in the caudal region of the intrapariatal sulcus and in the lateral occipital sulcus--respond specifically to the Craik-O'Brien-Cornsweet illusion generated by high-pass filtered edges. Other visual areas, including primary visual cortex, also respond strongly to the retinotopic location of the edge, but these areas respond equally well to a line of matched contrast and detectability, rather than specifically to the brightness illusion. The reconstruction of surface and/or its brightness seems to be achieved by associative areas from the information about visual features provided by the primary visual cortices, even where there is no physical difference in luminance. 相似文献
56.
Esposito V Randazzo A Petraccone L Giancola C Erra E Virgilio A Mayol L 《Nucleosides, nucleotides & nucleic acids》2005,24(5-7):789-794
Truncated sequences of human telomeric DNA can readily assemble to form parallel stranded quadruplexes containing A- and G-tetrads. The formation of an A-tetrad is highly context-dependent and the relationship between the formation of an A-tetrad and the glycosidic torsion angle of the adenosine residues implicated has not been completely clarified so far. In order to give a further insight in this issue we synthesized the modified oligomers d(ABrGGGT) and d(TABrGGGT), two different truncations of the human telomeric sequence containing a 8-bromoadenosine residue, named ABr. NMR data show that both the modified oligomers are able to perfectly fold into highly symmetric quadruplexes with all strands parallel to each other. Molecular modeling studies were performed on both [d(ABrGGGT)]4 and [d(TABrGGGT)]4, indicating that a bulky substituent, such as a bromine atom at the C8 position of adenines, can force the glycosidic bond to adopt a syn conformation, stabilizing the resulting quadruplexes. 相似文献
57.
Marszalek JR Kitidis C Dirusso CC Lodish HF 《The Journal of biological chemistry》2005,280(11):10817-10826
Previously we demonstrated that supplementation with the polyunsaturated fatty acids (PUFA) arachidonic acid (AA) or docosahexaenoic acid (DHA) increased neurite outgrowth of PC12 cells during differentiation, and that overexpression of rat acyl-CoA synthetase long-chain family member 6 (Acsl6, formerly ACS2) further increased PUFA-enhanced neurite outgrowth. However, whether Acsl6 overexpression enhanced the amount of PUFA accumulated in the cells or altered the partitioning of any fatty acids into phospholipids (PLs) or triacylglycerides (TAGs) was unknown. Here we show that Acsl6 overexpression specifically promotes DHA internalization, activation to DHA-CoA, and accumulation in differentiating PC12 cells. In contrast, oleic acid (OA) and AA internalization and activation to OA-CoA and AA-CoA were increased only marginally by Acsl6 overexpression. Additionally, the level of total cellular PLs was increased in Acsl6 overexpressing cells when the medium was supplemented with AA and DHA, but not with OA. Acsl6 overexpression increased the incorporation of [(14)C]-labeled OA, AA, or DHA into PLs and TAGs. These results do not support a role for Acsl6 in the specific targeting of fatty acids into PLs or TAGs. Rather, our data support the hypothesis that Acsl6 functions primarily in DHA metabolism, and that its overexpression increases DHA and AA internalization primarily during the first 24 h of neuronal differentiation to stimulate PL synthesis and enhance neurite outgrowth. 相似文献
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59.
Vinciguerra M Vivacqua A Fasanella G Gallo A Cuozzo C Morano A Maggiolini M Musti AM 《The Journal of biological chemistry》2004,279(10):9634-9641
MAPK phosphorylation of various substrates is mediated by the presence of docking sites, including the D domain and the DEF motif. Depending on the number and sequences of these domains, substrates are phosphorylated by specific subsets of MAPKs. For example, a D domain targets JNK to c-Jun, whereas a DEF motif is required for ERK phosphorylation of c-Fos. JunD, in contrast, contains both D and DEF domains. Here we show that these motifs mediate JunD phosphorylation in response to either ERK or JNK activation. An intact D domain is required for phosphorylation and activation of JunD by both subtypes of MAPK. The DEF motif acts together with the D domain to elicit efficient phosphorylation of JunD in response to the epidermal growth factor (EGF) but has no function on JunD phosphorylation and activation by JNK signaling. Furthermore, we show that conversion of a c-Jun sequence to a canonical DEF domain, as it is present in JunD, elicits c-Jun activation in response to EGF. Our results suggest that evolution of a particular modular system of MAPK targeting sequences has determined a differential response of JunD and c-Jun to ERK activation. 相似文献
60.
Optimization of recombinant human nerve growth factor production in the psychrophilic Pseudoalteromonas haloplanktis 总被引:1,自引:0,他引:1
The optimization of production strategy is a very useful tool to attain high level of recombinant protein at a low cost. A promising biotechnological application of psychrophilic bacteria is their use as non-conventional host for the recombinant production of useful proteins. The lowering of the expression temperature can in fact facilitate the correct folding of heterologous proteins that accumulate in insoluble form as inclusion bodies when produced in Escherichia coli. An example of such "difficult" proteins is the human nerve growth factor (hNGF). The gene encoding the mature form of hNGF was expressed in the Antarctic bacterium Pseudoalteromonas haloplanktis TAC125 at 4 degrees C. Western blotting experiments demonstrated that the protein was produced in soluble form and translocated in the periplasmic space. Furthermore, an analytical gel filtration chromatography confirmed that the recombinant protein was largely in dimeric form. For a more efficient recombinant rhNGF production, the influence of cultivation operational strategies and growth conditions (medium composition, temperature, specific growth rate) on biomass yield and recombinant protein production was investigated in batch and chemostat cultivations. The highest product yield of soluble rhNGF (7.5mg(NGF)g(dryweight)(-1)) has been achieved in batch culture at 4 degrees C on Schatz medium with addition of tryptone and vitamins. 相似文献