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排序方式: 共有213条查询结果,搜索用时 31 毫秒
11.
Maria Raffaella Greco Emeline Bon Rosa Rubino Lorenzo Guerra Manuel Bernabe-Garcia Stefania Cannone Maria-Luisa Cayuela Loredana Ciaccia Séverine Marionneau-Lambot Thibauld Oullier Gaëlle Fromont Roseline Guibon Sébastien Roger Stephan Joel Reshkin Rosa Angela Cardone 《生物化学与生物物理学报:疾病的分子基础》2019,1865(1):26-37
Metastatic cancer cells are highly plastic for the expression of different tumor phenotype hallmarks and organotropism. This plasticity is highly regulated but the dynamics of the signaling processes orchestrating the shift from one cell phenotype and metastatic organ pattern to another are still largely unknown. The scaffolding protein NHERF1 has been shown to regulate the expression of different neoplastic phenotypes through its PDZ domains, which forms the mechanistic basis for metastatic organotropism. This reprogramming activity was postulated to be dependent on its differential phosphorylation patterns. Here, we show that NHERF1 phosphorylation on S279/S301 dictates several tumor phenotypes such as in vivo invasion, NHE1-mediated matrix digestion, growth and vasculogenic mimicry. Remarkably, injecting mice with cells having differential NHERF1 expression and phosphorylation drove a shift from the predominantly lung colonization (WT NHERF1) to predominately bone colonization (double S279A/S301A mutant), indicating that NHERF1 phosphorylation also acts as a signaling switch in metastatic organotropism. 相似文献
12.
Post-partum depression (PPD) presents a significant disruption to the mother-infant relationship. Such disruptions are associated with risks to the neurological, socio-emotional and cognitive functioning of the developing infant. A review of this literature supports the early detection of PPD and the application of comprehensive, psychotherapeutic interventions that target the functioning of the infant, the mother and the mother-infant relationship. Ecological factors important to evaluation and avenues of intervention are emphasised. The need for further research to determine evidence-based methods of intervention is described. 相似文献
13.
MALDI-TOF MS of phosphatidylethanolamines: different adducts cause different post source decay (PSD) fragment ion spectra 总被引:2,自引:0,他引:2
Fuchs B Schober C Richter G Süss R Schiller J 《Journal of biochemical and biophysical methods》2007,70(4):689-692
Matrix-assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI-TOF MS) is increasingly applied to lipids. However, positional acyl chain analysis of lipids by MALDI was so far scarcely described. In this paper, the fragmentation behavior of phosphatidylethanolamine (PE) is investigated by using post-source decay (PSD) MS. In dependence on the investigated adduct, significant differences could be obtained. It will be shown that in particular the negative ion spectra enable the determination of the individual acyl chains as well as their positions (sn-1 or sn-2). Therefore, MALDI-TOF PSD spectra are a real alternative to more sophisticated MS/MS methods. 相似文献
14.
A centrifugal dehydration force (CDF) method to quantify changes in tissue hydration in fresh and in post-mortem muscular fish tail tissue is presented. The data obtained were used to assess fluid flow rate from tissues and the size of hydration compartments expressed in g water/g dry mass (DM). Curve fit analysis demonstrated that muscle tissue has three detectable water compartments. Application of the method to the fresh fish indicated the presence of a large non-bulk water compartment (3.14 g water/g DM) with a much smaller (0.11 g water/g DM) inner non-bulk water sub-compartment in addition to a comparatively small bulk water compartment (0.99 g water/g DM). At 10 min and at 4h post-mortem, no significant change in size or flow rate of the water compartments was observed. At 24h post-mortem the muscular fish tissue, stored in water, swelled with statistically significant increase in total water and in the bulk water compartment but no significant change in the size of the non-bulk water compartments. The water flow rate from the non-bulk water compartment was, however, increased significantly in the 24h dead tissue. This simple CDF method has application for quantization of bulk and non-bulk water compartments in other biological and non-biological systems. 相似文献
15.
描述了一件象属( Elephas) 的右上臼齿化石。标本产自查谟紧靠上西瓦立克亚群巨砾岩组( Boulder Conglomerate Formation) 之上的砂质、粉砂质泥岩夹砾石层中,化石地点位于查谟市南10 km,Kharian 村北约500 m 处。根据齿板数、齿脊频率、釉质层厚度、冠高指数、绝对大小和齿长/齿高指数等牙齿形态参数,暂时将之归为 Elephas cf. E. maximus indicus。还简短讨论了象属的地理分布和地质时代。 相似文献
16.
Colgrave ML Xi L Lehnert SA Flatscher-Bader T Wadensten H Nilsson A Andren PE Wijffels G 《Proteomics》2011,11(7):1264-1276
The hypothalamus is the central regulatory region of the brain that links the nervous system to the endocrine system via the pituitary gland. It synthesizes and secretes neuropeptide hormones, which in turn act to stimulate or inhibit the secretion of pituitary hormones. We have undertaken a detailed MS investigation of the peptides present in the bovine hypothalamus by adapting a novel heat stabilization methodology, which improved peptide discovery to direct our studies into the molecular mechanisms involved in bovine reproduction. The untreated samples contained large numbers of protein degradation products that interfered with the analysis of the neuropeptides. In the thermally stabilized samples, we were able to identify many more neuropeptides that are known to be expressed in the bovine hypothalamus. Furthermore, we have characterized a range of post-translational modifications that indicate the presence of processed intact mature neuropeptides in the stabilized tissue samples, whereas we detected many trimmed or truncated peptides resulting from post-mortem degradation in the untreated tissue samples. Altogether, using an optimized workflow, we were able to identify 140 candidate neuropeptides. We also nominate six new candidate neuropeptides derived from proSAAS, secretogranin-2 and proTRH. 相似文献
17.
Phosphoproteomic analysis using immobilized metal ion affinity chromatography on the basis of cellulose powder 总被引:2,自引:0,他引:2
Feuerstein I Morandell S Stecher G Huck CW Stasyk T Huang HL Huber LA Bonn GK 《Proteomics》2005,5(1):46-54
Detailed characterization of phosphoproteins as well as other post-translationally modified proteins such as glycoproteins, is required to fully understand protein function and regulatory events in cells and organisms. Therefore, an experimental strategy for the isolation of phosphoproteins using a new immobilized metal ion affinity chromatograph (IMAC) material on the basis of cellulose has been developed and characterized. Different approaches have been used to test the material. Recovery rates were determined by 32P labelling of a myelin basic protein fragment and by reversed-phase high-performance liquid chromatography-electrospray ionization mass spectrometry using a tryptic digest of the model protein bovine beta-casein. Selectivity was demonstrated by enrichment and separation of phosphopeptides from different samples, such as from a digest of horse myoglobin as well as from a digest of in vitro phosphorylated extracellular signal regulates kinase 2 (ERK2) mixed with synthetic phosphopeptides, phosphorylated on different amino acid residues. Furthermore, simplification and optimization of sample pretreatment was achieved by combining the separating (IMAC) and desalting (C18) step during preparative high performance liquid chromatography. The comparison between our material and a commercially available IMAC system (POROS 20 MC; Perspective BioSystems) emphasizes the competitiveness of the cellulose. Confirmed by the obtained data, the cellulose material performed as well as the commercially available sorbent, however with the advantage, that it can be produced rather easily and at very low cost. 相似文献
18.
In order to elucidate the roles of human growth hormone (hGH) in the normal (control) pituitary and in adenomas, the hGH isoforms in the human pituitary were analyzed with two-dimensional gel electrophoresis, immobilized metal affinity column (Ga(+3)) chromatography, mass spectrometry (MS), and bioinformatics. Twenty-four hGH-containing proteins, with significantly different expression proportions of their isoforms were found. The proportions of isoforms were as follows: isoform 1 (87.5%) > isoform 2 (8.1%) > isoform 3 (3.3%) > isoform 4 (1.1%). Deamidation of asparagine to aspartate was identified with matrix-assisted laser desorption/ionization-time of flight MS. Tandem mass spectrometry data demonstrated that hGH is a phosphoprotein (spot 6); phosphorylation was found at Ser-77 in the tryptic peptide (68)YSFLQNPQTSLCFSESIPTPSNR(90), at Ser-176 in the tryptic peptide (172)FDTNSHNDDALLK(184), and at Ser-132 in the peptide (126)SLVYGASDSNVYDLLK(141). The phosphorylation sites at Ser-77 and Ser-176 were consistent with computer-program predictions (NetPhos). These results provide novel clues for further studies of the functions, and mechanisms of action, of hGH in the human pituitary and in growth hormone-related diseases. 相似文献
19.
Timothy Reed Gerald H. Lushington Yan Xia Hidehiko Hirakawa DeAnna M. Travis Minae Mure Emily E. Scott Julian Limburg 《The Journal of biological chemistry》2010,285(33):25782-25791
Histamine dehydrogenase (HADH) isolated from Nocardioides simplex catalyzes the oxidative deamination of histamine to imidazole acetaldehyde. HADH is highly specific for histamine, and we are interested in understanding the recognition mode of histamine in its active site. We describe the first crystal structure of a recombinant form of HADH (HADH) to 2.7-Å resolution. HADH is a homodimer, where each 76-kDa subunit contains an iron-sulfur cluster ([4Fe-4S]2+) and a 6-S-cysteinyl flavin mononucleotide (6-S-Cys-FMN) as redox cofactors. The overall structure of HADH is very similar to that of trimethylamine dehydrogenase (TMADH) from Methylotrophus methylophilus (bacterium W3A1). However, some distinct differences between the structure of HADH and TMADH have been found. Tyr60, Trp264, and Trp355 provide the framework for the “aromatic bowl” that serves as a trimethylamine-binding site in TMADH is comprised of Gln65, Trp267, and Asp358, respectively, in HADH. The surface Tyr442 that is essential in transferring electrons to electron-transfer flavoprotein (ETF) in TMADH is not conserved in HADH. We use this structure to propose the binding mode for histamine in the active site of HADH through molecular modeling and to compare the interactions to those observed for other histamine-binding proteins whose structures are known. 相似文献
20.
Alexandra Castilho Laura Neumann Sasha Daskalova Hugh S. Mason Herta Steinkellner Friedrich Altmann Richard Strasser 《The Journal of biological chemistry》2012,287(43):36518-36526
Proper N- and O-glycosylation of recombinant proteins is important for their biological function. Although the N-glycan processing pathway of different expression hosts has been successfully modified in the past, comparatively little attention has been paid to the generation of customized O-linked glycans. Plants are attractive hosts for engineering of O-glycosylation steps, as they contain no endogenous glycosyltransferases that perform mammalian-type Ser/Thr glycosylation and could interfere with the production of defined O-glycans. Here, we produced mucin-type O-GalNAc and core 1 O-linked glycan structures on recombinant human erythropoietin fused to an IgG heavy chain fragment (EPO-Fc) by transient expression in Nicotiana benthamiana plants. Furthermore, for the generation of sialylated core 1 structures constructs encoding human polypeptide:N-acetylgalactosaminyltransferase 2, Drosophila melanogaster core 1 β1,3-galactosyltransferase, human α2,3-sialyltransferase, and Mus musculus α2,6-sialyltransferase were transiently co-expressed in N. benthamiana together with EPO-Fc and the machinery for sialylation of N-glycans. The formation of significant amounts of mono- and disialylated O-linked glycans was confirmed by liquid chromatography-electrospray ionization-mass spectrometry. Analysis of the three EPO glycopeptides carrying N-glycans revealed the presence of biantennary structures with terminal sialic acid residues. Our data demonstrate that N. benthamiana plants are amenable to engineering of the O-glycosylation pathway and can produce well defined human-type O- and N-linked glycans on recombinant therapeutics. 相似文献