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Integration of biological networks and gene expression data using Cytoscape   总被引:1,自引:0,他引:1  
Cytoscape is a free software package for visualizing, modeling and analyzing molecular and genetic interaction networks. This protocol explains how to use Cytoscape to analyze the results of mRNA expression profiling, and other functional genomics and proteomics experiments, in the context of an interaction network obtained for genes of interest. Five major steps are described: (i) obtaining a gene or protein network, (ii) displaying the network using layout algorithms, (iii) integrating with gene expression and other functional attributes, (iv) identifying putative complexes and functional modules and (v) identifying enriched Gene Ontology annotations in the network. These steps provide a broad sample of the types of analyses performed by Cytoscape.  相似文献   
85.
We demonstrated the immunoreactivity of the receptor proteins, VR1, ion channels associated with pain sensation, on the epidermis of the human skin. Immunohistochemistry using antiserum against VR1 derived peptide showed immunoreactivity on the keratinocytes cell membrane of the human epidermis and cultured keratinocytes. The blocking peptide of the antiserum reduced the immunoreactivity on the epidermis. RT-PCR assay of cultured human keratinocyte also showed expression of VR1 mRNA. These results suggest the existence of VR1-like protein in epidermal keratinocytes of human skin.  相似文献   
86.
Boron (B) deficiency results in inhibition of pumpkin (Cucurbia moschata Duchesne) growth that is accompanied by swelling of the cell walls. Monomeric rhamnogalacturonan II (mRG-II) accounted for 80% to 90% of the total RG-II in B-deficient walls, whereas the borate ester cross-linked RG-II dimer (dRG-II-B) accounted for more than 80% of the RG-II in control plants. The results of glycosyl residue and glycosyl linkage composition analyses of the RG-II from control and B-deficient plants were similar. Thus, B deficiency does not alter the primary structure of RG-II. The addition of (10)B-enriched boric acid to B-deficient plants resulted within 5 h in the conversion of mRG-II to dRG-II-(10)B. The wall thickness of the (10)B-treated plants and control plants was similar. The formation and possible functions of a borate ester cross-linked RG-II in the cell walls are discussed.  相似文献   
87.
Alpha1,3-fucosyltransferase (Fuc TVII) is a key enzyme in the biosynthesis of selectin ligands. We have isolated two inhibitors of Fuc TVII from a marine sponge Sarcotragus sp. They were characterized as octa- and nonaprenylhydroquinone sulfates on the basis of spectral data. These compounds inhibited Fuc-TVII with IC50 values of 3.9 and 2.4 microg/mL, respectively.  相似文献   
88.
 In a previous report, a novel selection protocol termed "the MAT-vector system" for generating marker-free transgenic plants (MFTPs) was presented. The first stage of the system is visual selection of morphologically abnormal transgenic shoots, ipt-shooty, that have lost apical dominance and rooting ability. The second stage involves elimination of the ipt gene and the appearance of MFTPs free of ipt gene influence. The present report describes a practical MAT-vector in which removal of the ipt gene is efficiently mediated by the site-specific recombination system R/RS from Zygosaccharomyces rouxii, in place of the maize transposable element Ac, used previously. This improved MAT-vector produced MFTPs from 39% of moderate ipt-shooty and 70% of extreme ipt-shooty lines. These results are superior to the previous MAT-vector which produced MFTPs from only 5% of ipt-shooty lines. The present novel system also induced direct development of MFTPs from adventitious buds without production of ipt-shooty intermediates. The presence of β-glucuronidase (GUS) and neomycin phosphotransferase (NPTII) genes of interest, and the absence of the ipt gene were verified by a GUS histochemical assay, NPTII assay, and molecular analysis. Received: 19 June 1998 / Revision received: 4 December 1998 / Accepted: 18 December 1998  相似文献   
89.
The fractal dimension, Df, of aggregates in a dilute BSA system with added salt was evaluated by static light scattering (SLS). A fractal structure was observed for the system with NaCl addition. The values of Df increased with increasing heating time and ionic strength. The values of Df were larger than those (Df = 1.8 or 2.1) predicted by the conventional cluster-cluster aggregation model, probably due to a "restructuring" of aggregates during the aggregation process. On the other hand, a fractal structure was not apparent for the system with added CaCl2.  相似文献   
90.
The location of the 1:2 borate-diol ester cross-link in the dimer of the plant cell wall polysaccharide rhamnogalacturonan II (RG-II) has been determined. The ester cross-links the apiofuranosyl residue of the 2-O-methyl-D-xylose-containing side chains in each of the subunits of the dimer. The apiofuranosyl residue in each of the two aceric acid-containing side chains is not esterified. The site of borate esterification is identical in naturally occurring and in in vitro synthesized dimer. Pb2+, La3+, and Ca2+ increase dimer formation in vitro in a concentration- and pH-dependent manner. Pb2+ is the most effective cation. The dimer accounts for 55% of the RG-II when the monomer (0.5 mM) is treated for 5 min at pH 3.5 with boric acid (1 mM) and Pb2+ (0.5 mM); at pH 5 the rate of conversion is somewhat slower. Hg2+ does not increase the rate of dimer formation. A cation's charge density and its ability to form a coordination complex with RG-II, in addition to steric factors, may regulate the rate and stability of dimer formation in vitro. Our data provide evidence that the structure of RG-II itself determines which apiofuranosyl residues are esterified with borate and that in the presence of boric acid and certain cations, two RG-II monomers self-assemble to form a dimer.  相似文献   
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