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Kawaoka Akiyoshi; Sato Shinichi; Nakahara Ko; Matsushima Naohito; Okada Naosuke; Sekine Masami; Shinmyo Atsuhiko; Takano Mitsuo 《Plant & cell physiology》1992,33(8):1143-1150
The expression and promoter activity of genes for isozymes ofhorseradish peroxidase, namely, prxCla, prxClb, prxC2 and prxC3,were studied. Organ-specific expression of these genes in horseradishplants was examined by Northern blot analysis. The group ofprxCl genes was expressed mostly in stems, while prxC2 and prxC3were expressed to a greater extent in roots. Hardly any expressionof any of the genes was detected in leaves. In transient-expressionassays with tobacco protoplasts, about 500 bp of the 5'-noncodingregions of each of the genes, ligated to the gene for ß-glucuronidase(GUS), exhibited significant promoter activity. In particular,the fragments extending from the initiation codon of the prxC2gene to 529 bp and 1 kbp supported high levelsof GUS activity, which were 4.4 and 11.4 times respectively,the activity observed under control of the 35S promoter fromcauliflower mosaic virus (CaMV). Conserved enhancer sequencesof human genes were found in the 5'-flanking region of prxC2,and deletion of the regions that contained the enhancer sequencesreduced the GUS activity. High levels of GUS activity were observedin transgenic tobacco plants that contained 1 kbp of the 5'flanking region of prxC2 fused to the GUS gene. GUS activitywas diminished when deletion from the 5' end extended as faras the CAAT box. No significant organ-specific expression ofGUS was observed with any such deletion. (Received April 15, 1992; Accepted September 11, 1992) 相似文献
35.
Formation and characterization of antibody against 2''-(5"-phosphoribosyl)-5'' AMP, the monomer form of poly(adenosine diphosphate ribose). 总被引:1,自引:0,他引:1 下载免费PDF全文
Specific antibody against 2'-(5"-phosphoribosyl)-5'AMP (PR-AMP), a monomer of poly(adenosine diphosphate ribose) (poly(ADP-Rib)), was produced by immunizing a rabbit with PR-AMP coupled to bovine serum albumin (BSA). Antibody against PR-AMP was purified 53-fold from serum by (NH4) 2SO4 precipitation, and BSA-Sepharose 4B, DEAE-cellulose and (PR-AMP)-BSA-Sepharose 4B column chromatographies. Inhibition experiments show that the adenine ring, 5'-phosphate residue and ribose-ribose bond of PR-AMP were essential for the antigenic determinant of PR-AMP. Anti PR-AMP antibody bound, not only with PR-AMP, but also with poly(ADP-Rib) of various chain lengths, while anti poly(ADP-Rib) antibody bound with poly(ADP-Rib) but not with PR-AMP. 相似文献
36.
The relationship between the structure and function of ferricytochrome c bound to the phosphoprotein phosvitin was investigated. The rates of reduction of phosvitin-bound ferricytochrome c by cytochrome b2, ascorbate and the superoxide radical generated by xanthine oxidase wer repressed where the binding ratio was less than half the maximum, but at higher ratios they were restored gradually with increase in the ratio. The affinity of cytochrome b2 for cytochrome c was not affected by binding of cytochrome c to phosvitin. The redox potential of the bond form was lower than that of the free form and only decreased with decrease in the ratio. The conformatin around the heme moiety and the electronic structure of the heme group of bound ferricytochrome c were similar to those of free ferricytochrome c, but the conformational stability in the vicinity of the prosthetic group was related to the binding ratio as ratios above half the maximum and was well correlated with the reduction rate. Since the binding of cytochrome c to phosvitin is much stronger at binding ratios below half the maximum, these results suggest that this binding strength exclusively affects the conformational flexibility of the heme crevice in the cytochrome molecule, thus altering the reduction rate. 相似文献
37.
H Sakura M Miwa M Tanaka Y Kanai T Shimada T Matsushima T Sugimura 《Nucleic acids research》1977,4(8):2903-2915
Evidence for the natural occurrence of poly(adenosine diphosphate ribose) in vivo was obtained using a sensitive radioimmunoassay and poly(adenosine diphosphate ribose) glycohydrolase, which specifically hydrolyzes poly(adenosine diphosphate ribose). Calf thymus, liver, kidney, brain, pancreas and spleen contained poly(adenosine diphosphate ribose). Naturally occurring poly(adenosine diphosphate ribose) in calf thymus is composed of molecules of various chain lengths, like that synthesized by an in vitro system. Calf thymus was estimated to contain about 0.02 microgram/mg DNA of poly(adenosine diphosphate ribose). 相似文献
38.
Crystal structure of the human Fab fragment Kol and its comparison with the intact Kol molecule 总被引:6,自引:0,他引:6
M Matsushima M Marquart T A Jones P M Colman K Bartels R Huber 《Journal of molecular biology》1978,121(4):441-459
The crystal structure of the Fab3 fragment of the IgG protein Kol was analysed and an electron density map calculated at 3 Å resolution based on phases obtained from multiple isomorphous replacement. An atomic model was constructed but the lack of amino acid sequence data causes some uncertainty, in particular concerning the amino acid side-chains. Several cycles of constrained crystallographic refinement (Deisenhofer &; Steigemann, 1975) produced an R value of 0.36. The resulting model was compared with the intact Kol IgG crystal structure (Colman et al., 1976), which had also been subjected to constrained crystallographic refinement, and two Fab fragments (Davies et al., 1975). The elbow angle was found open and only 8 ° more bent than in intact Kol, in contrast to the other Fab fragments, which show a strongly bent elbow angle. The intramolecular longitudinal V-C contacts are very similar in Kol Fab and Kol IgG and considerably fewer in number than in the other Fab fragments. The lateral V-V and C-C association is virtually identical in Kol Fab and Kol IgG. Although Kol Fab and Kol IgG crystallize in different lattices, they exhibit a nearly identical head to tail packing of the Fab parts, with the C modules touching the hypervariable segments of the V modules. This strongly conserved particular mode of aggregation might be reflected in the property of cold precipitation of the Kol cryoglobulin. 相似文献
39.
Crystal structures of the apo- and holomutant human lysozymes with an introduced Ca2+ binding site 总被引:3,自引:0,他引:3
K Inaka R Kuroki M Kikuchi M Matsushima 《The Journal of biological chemistry》1991,266(31):20666-20671
The three-dimensional structures of apo- and holomutant human lysozymes (D86/92 lysozyme), in which a calcium binding site was designed and created for enhancing molecular stability by replacing both Gln86 and Ala92 with aspartic acids, were refined at 1.8-A resolution by x-ray crystallography. The overall structures and crystallographic thermal factors of all three proteins, the apo-, holo-D86/92, and the wild-type human lysozymes, were essentially identical; these results showed that the introduction of the calcium binding site did not affect either the overall structure or molecular rigidity of the proteins. However, structure analyses of the apo-D86/92 lysozyme revealed that the mutations affected the side chain conformation of residue 86 and hydrogen networks between the protein and the internal solvent molecules. In the structure of the holo-D86/92 lysozyme, seven oxygen ligands formed a slightly distorted pentagonal bipyramid around the calcium ion, indicating that the coordination around the calcium ion was quite similar to that in baboon alpha-lactalbumin. The pentagonal bipyramid coordination could be one of the most widely found and appropriate calcium binding schemes in proteins. 相似文献
40.
The signal transduction pathway involved in the migration induced by a monocyte chemotactic cytokine 总被引:16,自引:0,他引:16
S Sozzani W Luini M Molino P Jílek B Bottazzi C Cerletti K Matsushima A Mantovani 《Journal of immunology (Baltimore, Md. : 1950)》1991,147(7):2215-2221
Recombinant monocyte-chemotactic and activating factor (rMCAF; alternative acronyms MCP-1, TDCF, human JE) induced migration of human monocytes across polycarbonate or nitrocellulose filters. Maximal induction of migration was observed at a concentration of 10 ng/ml (10(-9) M). Checkerboard analysis revealed that rMCAF elicited true gradient-dependent chemotactic migration, although a gradient independent chemokinetic effect was observed at low concentrations (1-5 ng/ml). rMCAF caused a rapid (less than 5 s) and transient (approximately 1.5 min) increase of free cytosolic Ca2+ ions, as assessed by the fura-2 probe. No Ca2+ increase was detected in neutrophils or lymphocytes stimulated by rMCAF. Studies conducted in the absence of extracellular Ca2+ or in the presence of Ni2+ (an inhibitor of Ca2+ influx) suggested that the increase of intracellular Ca2+ induced by rMCAF is dependent on the influx of extracellular Ca2+ through plasma membrane channels. Bordetella pertussis toxin inhibited the intracellular Ca2+ elevation and chemotaxis caused by rMCAF. The possible involvement of Ca(2+)-dependent protein kinases in rMCAF signaling pathway(s) was explored using inhibitors. Inhibitors of GMP-dependent kinase and myosin L chain kinase had no effect on rMCAF-induced monocyte migration. In contrast, protein kinase C/cAMP-dependent kinase inhibitors (such as, C-I, H-7, HA-1004, KT5720, and Staurosporine) markedly decreased rMCAF induced chemotaxis suggesting the involvement of a serine/threonine protein kinase, possibly protein kinase C, in rMCAF signaling pathway. 相似文献