Takahashi K, Takahashi F, Tanabe KK
… +2 more, Takahashi H, Fukuchi Y
Biochem Mol Biol Int
· 1998 Dec · PMID 9891840
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Osteopontin (OPN) is a secreted glycoprotein implicated in cell adhesion. It contains the arginine-glycine-asparatic acid (RGD) cell adhesive domain and the thrombin cleavage sequence. Although thrombin cleavage of OPN h...Osteopontin (OPN) is a secreted glycoprotein implicated in cell adhesion. It contains the arginine-glycine-asparatic acid (RGD) cell adhesive domain and the thrombin cleavage sequence. Although thrombin cleavage of OPN has been shown to be of physiological importance, the function of C-terminal OPN fragment cleaved by thrombin remains unknown. To determine its role, we performed cell adhesion assays using glutathione S-transferase-OPN fusion protein fragments and full-length OPN fusion protein. The N-terminal fragment containing RGD motif promoted enhanced adhesion of mouse and human fibroblasts by 2.9 and 2.8 folds in comparison with full-length OPN, respectively. The enhanced adhesion of both cells mediated by N-terminal fragment was significantly suppressed by addition of C-terminal fragment lacking RGD motif that has less cell adhesive property than full-length OPN. These results suggest that the C-terminal domain may play a pivotal role in regulating OPN functions by suppressing the RGD-dependent cell adhesion.
Biochem Mol Biol Int
· 1998 Dec · PMID 9891839
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The ecto form of adenosine deaminase isolated from human placental membrane was tested towards its sensitivity against adenosine deaminase inhibitors, such as aza and deaza analogues of adenosine and erythro-9-(2-hydroxy...The ecto form of adenosine deaminase isolated from human placental membrane was tested towards its sensitivity against adenosine deaminase inhibitors, such as aza and deaza analogues of adenosine and erythro-9-(2-hydroxy-3-nonyl)adenine (EHNA). Ki values of the inhibitors observed were similar to these obtained for the small form of adenosine deaminase purified from human erythrocytes, indicating that the presence of the binding protein on placental adenosine deaminase does not produce alteration in the binding of these inhibitors on the enzyme active site. The inhibition rate of 2'-deoxycoformycin, one of the most potent ADA inhibitors is affected by the presence of the binding protein on human placental adenosine deaminase, that probably modulates the rearrangement of the active site produced by the binding with this tight-binding inhibitor.
Biochem Mol Biol Int
· 1998 Dec · PMID 9861460
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Helicobacter pylori lipopolysaccharide is recognized as a primary virulence factor evoking acute mucosal inflammatory reaction associated with H. pylori infection. We investigated the activity of a key apoptotic protease...Helicobacter pylori lipopolysaccharide is recognized as a primary virulence factor evoking acute mucosal inflammatory reaction associated with H. pylori infection. We investigated the activity of a key apoptotic protease, caspase-3, and the expression of inducible nitric oxide synthase (NOS-2) during H. pylori lipopolysaccharide-induced acute gastritis. The assays conducted 4 days following intragastric dose of the lipopolysaccharide revealed a pattern of acute mucosal responses characterized by an 11.2-fold increase in epithelial cells apoptosis, inflammatory infiltration of the lamina propria, hyperemia, and epithelial hemorrhage. This was accompanied by a 5.4-fold increase in caspase-3 activity, while the mucosal expression of NOS-2 showed a 6.5-fold induction. The results implicate H. pylori lipopolysaccharide in the induction of NOS-2 expression, and point to its effect on activation of the signaling cascade involving caspase-3 in the process gastric epithelial cells apoptosis.
Shono M, Shimizu I, Omoya T
… +4 more, Hiasa A, Honda H, Tomita Y, Ito S
Biochem Mol Biol Int
· 1998 Dec · PMID 9861459
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To simply and directly evaluate DNA fragmentation during apoptosis induced in mouse cultured hepatocytes by an anti-Fas antibody, we examined the fluorescence intensity in cell nuclei stained with ethidium bromide and 4'...To simply and directly evaluate DNA fragmentation during apoptosis induced in mouse cultured hepatocytes by an anti-Fas antibody, we examined the fluorescence intensity in cell nuclei stained with ethidium bromide and 4'-6-diamidino-2-phenylindole by optiphoto fluorescence microscopy. The intensity of the former staining for the nuclear DNA of apoptotic cells was clearly decreased compared to that of non-apoptotic cells, whereas no difference in the fluorescence intensity for the latter stain between the apoptotic and non-apoptotic groups was observed. Thus, the use of optiphoto fluorescence microscopy, in conjunction with both stains, constitutes a useful tool for the evaluation of apoptotic DNA fragmentation.
Biochem Mol Biol Int
· 1998 Dec · PMID 9861458
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Three constitutive gelatinases in human plasma were identified and characterized relative to known matrix metalloproteinase (MMP) gelatinases: MMP-2 (fibroblast 72-kDa) and MMP-9 (neutrophil 92-, 130-, and 225-kDa). Subs...Three constitutive gelatinases in human plasma were identified and characterized relative to known matrix metalloproteinase (MMP) gelatinases: MMP-2 (fibroblast 72-kDa) and MMP-9 (neutrophil 92-, 130-, and 225-kDa). Substrate gel electrophoresis (gelatin zymography) revealed an apparent Mw of 78-, 82-, and 89-kDa for these gelatinases. Densitometry revealed that MMP-9 and MMP-2 were highly calcium sensitive requiring 50-150 microM and 500 microM calcium for half-maximal activity, respectively. Of the new gelatinases, only the 89-kDa form demonstrated slight calcium activation. The three gelatinases were unaffected by known MMP inhibitors: EDTA (5 mM), 1,10-phenanthroline (2 mM), and pepstatin (18 microM). Serine and thiol protease inhibitors (leupeptin, aprotinin, PMSF, TLCK, TPCK, antichymostatin, antipain) were also ineffective. Solution-phase IEF revealed that the 78- and 82-kDa forms focused at neutral pI 6.72-7.95 whereas the 89-kDa focused at an acidic pI 4.89-5.18 (similar to neutrophil and fibroblast forms). The data indicate that these gelatinases are not MMPs or partially activated MMPs. Their role in normal and pathological conditions is not known.
Mortensen KK, Kildsgaard J, Moreno JM
… +3 more, Steffensen SA, Egebjerg J, Sperling-Petersen HU
Biochem Mol Biol Int
· 1998 Dec · PMID 9861457
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The Escherichia coli translation initiation factor IF2 is a 97 kDa protein which interacts with the initiator fMet-tRNAfMet, GTP and the ribosomal subunits during initiation of protein biosynthesis. For structural and fu...The Escherichia coli translation initiation factor IF2 is a 97 kDa protein which interacts with the initiator fMet-tRNAfMet, GTP and the ribosomal subunits during initiation of protein biosynthesis. For structural and functional investigations of the factor, we have raised and characterised monoclonal antibodies against E. coli IF2. Twelve epitopes have been localised at the surface of the protein molecule by three different methods: Interactions of the monoclonal antibodies with nested deletion mutants of IF2, comparison of the relative location of the epitopes in a competition immunoassay and cross-reactivity analyses of the monoclonal antibodies towards IF2 from Salmonella typhimurium, Klebsiella oxytoca, Enterobacter cloacae, Proteus vulgaris, and Bacillus stearothermophilus. These data are combined with predicted secondary structure and discussed in relation to a six-domain structural model for IF2. The model describes IF2 as a slightly elongated molecule with a structurally compact C-terminal domain, a well-conserved central GTP-binding domain, and a highly charged, solvent exposed N-terminal with protruding alpha-helical structures.
Biochem Mol Biol Int
· 1998 Dec · PMID 9861456
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The effects of alpha-Hederin, a triterpenoid saponin which exists in some oriental herbs, on the expression of liver cytochrome P450s were examined in mice. The administration of alpha-Hederin to mice significantly decre...The effects of alpha-Hederin, a triterpenoid saponin which exists in some oriental herbs, on the expression of liver cytochrome P450s were examined in mice. The administration of alpha-Hederin to mice significantly decreased the hepatic content of P450 and the activities of microsomal ethoxyresorufin O-deethylase, methoxyresorufin O-demethylase, and aniline hydroxylase, representative activities of cytochrome-P4501A1, -P4501A2, and -P4502E1, respectively, in a dose- and time-dependent manner. However, pentoxyresorufin O-dealkylase, a representative activity of cytochrome P4502B1/2, was decreased to a lesser extent. alpha-Hederin also decreased inducible monooxygenase activities in the same manner. Suppressions of P450 isozyme expression occurred in alpha-Hederin treated hepatic microsomes, as determined by immunoblot analysis in a manner consistent with that of the enzyme activity levels. Levels of mRNA of P4501A1/2 and P4502B1/2 were also decreased by alpha-Hederin as shown by Northern blot analysis. In contrast, the level of P4502E1 mRNA in the liver of alpha-Hederin treated mice was unchanged. These results suggest that alpha-Hederin may act as a more specific suppressor for P4501A and P4502E1 than P4502B and that the suppression involves decreases in mRNA levels except in the case of P4502E1.
Senna SM, Moraes RB, Bravo MF
… +8 more, Oliveira RR, Miotto GC, Vidor AC, Belló-Klein A, Irigoyen MC, Belló AA, Curi R, Homem de Bittencourt PI
Biochem Mol Biol Int
· 1998 Dec · PMID 9861455
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Macrophages/foam cells have a pivotal role in atherogenesis although little is known about the way lipid imbalance, a hallmark of atherosclerosis, leads to lipid accumulation in these cells. Modified low-density lipoprot...Macrophages/foam cells have a pivotal role in atherogenesis although little is known about the way lipid imbalance, a hallmark of atherosclerosis, leads to lipid accumulation in these cells. Modified low-density lipoproteins are associated with macrophage lipid dysfunction in atherosclerosis, but a possible role for altered lipogenesis leading to lipid accumulation remains to be elucidated. Since endothelium-derived nitric oxide (NO) and prostaglandins (PGs) are physiological autacoids whose production may be impaired in atherosclerosis, the effects of these mediators on de novo lipid synthesis in 24-h cultured rat peritoneal macrophages is investigated. In resident (unstimulated) cells, 1 microM PGE2 and the stable analog of PGI2 carbaprostacyclin (cPGI2, 1 microM) deviated the overall [1-14C]acetate from incorporation into cholesterol, free fatty acids and triacylglycerols favoring the formation of phospholipids. In inflammatory (thioglycollate-elicited) macrophages, these eicosanoids likewise reduced 14C-incorporations into all the lipid fractions tested. Also, cPGI2 and PGE2 reduced [4-14C]cholesterol uptake from inflammatory cells but did not interfere in 14C-cholesterol export. The PGE2-derivative PGA2 (10-20 microM) reduced 14C-incorporations into all the lipids in resident cells while it enhanced phospholipid synthesis by up to 129% at the expense of reduced incorporations into the other test lipids. The NO donor S-nitroso-N-acetylpenicillamine (SNAP, 1-10 microM), when added to macrophages in the presence of superoxide dismutase (SOD, to avoid the reaction of superoxide with NO), significantly reduced lipogenesis especially in inflammatory cells. These findings suggest that endothelium-derived NO and PGs may be associated with macrophage lipid accumulation by modulating lipogenesis and cholesterol uptake within these cells.
Biochem Mol Biol Int
· 1998 Dec · PMID 9861454
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The enzymes phospholipase D and diacylglycerol kinase generate phosphatidic acid which is considered to be a mitogen. Here we report that sphingosine produced a significant amount of phosphatidic acid in vascular smooth...The enzymes phospholipase D and diacylglycerol kinase generate phosphatidic acid which is considered to be a mitogen. Here we report that sphingosine produced a significant amount of phosphatidic acid in vascular smooth muscle cells from the rat aorta. The diacylglycerol kinase inhibitor R59 949 partially depressed sphingosine induced phosphatidic acid formation, suggesting that activation of phospholipase C and diacylglycerol kinase can not account for the bulk of phosphatidic acid produced and that additional pathways such as phospholipase D may contribute to this. Further, we have shown that phosphatidylethanol was produced by sphingosine when vascular smooth muscle cells were stimulated in the presence of ethanol. Finally, as previously shown for other cell types, sphingosine stimulated mitogen-activated protein kinase in vascular smooth muscle cells.
Tsukamoto H, Kurokawa T, Hirata K
… +2 more, Ishibashi S, Mishima HK
Biochem Mol Biol Int
· 1998 Dec · PMID 9861453
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We investigated the effect of two isomers of retinoic acid (RA), all-trans RA and 9-cis RA, on the proliferation of Y79 human retinoblastoma cells. The two isomers inhibited the cell proliferation in a concentration-depe...We investigated the effect of two isomers of retinoic acid (RA), all-trans RA and 9-cis RA, on the proliferation of Y79 human retinoblastoma cells. The two isomers inhibited the cell proliferation in a concentration-dependent manner. The IC50 for this inhibition by all-trans RA and 9-cis RA was 1.50 and 0.15 microM, respectively. The inhibitory effect of 9-cis RA on Y79 cell growth was observed within 24 hr, thereafter the cell number was gradually decreased. In contrast, no inhibition by all-trans RA of Y79 cell growth was observed within 24 hr, thereafter the cell number was slightly increased. In these cases, the cell viability at 4 days after the addition of 9-cis RA and all-trans RA was more than 90% and 95%, respectively. These results indicate that the two RA inhibit the proliferation of Y79 human retinoblastoma cells without inducing the cell death and that the effect of 9-cis RA on the inhibition of Y79 cell growth is much greater than that of all-trans RA.
Biochem Mol Biol Int
· 1998 Dec · PMID 9861452
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Cibacron Blue F3GA (CB) inhibited the activities of wheat leaves NADH:nitrate reductase and NADH:cytochrome-c reductase in a time-independent and concentration dependent manner. The methyl viologen:nitrate reductase acti...Cibacron Blue F3GA (CB) inhibited the activities of wheat leaves NADH:nitrate reductase and NADH:cytochrome-c reductase in a time-independent and concentration dependent manner. The methyl viologen:nitrate reductase activity of the enzyme was unaffected by various CB concentrations used in the experiment. Inhibition of NADH:nitrate reductase was of mixed type (partial competitive and pure noncompetitive) with respect to NADH and noncompetitive with respect to nitrate. The estimated inhibition constant (Ki) values were 1 microM for NADH and 8.4 microM for nitrate. The secondary plots of inhibition with respect to NADH, indicated a dissociation constant (KI) of 8.8 microM for the enzyme-NADH-CB complex. This KI being greater than the Ki suggested that the noncompetitive inhibition is predominant over the competitive inhibition at the NADH binding site.
Biochem Mol Biol Int
· 1998 Dec · PMID 9861451
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Three wild-type strains of Saccharomyces cerevisiae, viz. K, Y55 and sigma 1278b, two mutants lacking one or both of the putative K+ transporters, trk1 delta and trk1 delta trk2 delta, and a mutant in the plasma membrane...Three wild-type strains of Saccharomyces cerevisiae, viz. K, Y55 and sigma 1278b, two mutants lacking one or both of the putative K+ transporters, trk1 delta and trk1 delta trk2 delta, and a mutant in the plasma membrane H(+)-ATPase, viz. pma1-105, were compared in their extracellular acidification following addition of glucose and subsequent addition of KCl; in ATPase activity in purified plasma membranes; and in respiration on glucose. The glucose-induced acidification was the greater the higher the respiratory quotient, i.e. the higher the anaerobic metabolism. A markedly lower acidification was found in the ATPase-deficient pma1-105 strain but also in the TRK-deficient double mutant. The acidification pattern after addition of KCl corresponds to expectations in the TRK mutants; however, a similarly decreased acid production was found in the ATPase-deficient mutant pma1-105. The highest rate of ATP hydrolysis in vitro was found with the trk1 delta trk2 delta mutant where glucose-, as well as KCl-induced acidification were lowest. Likewise, the pma1-105 mutant with extremely low acidification showed only a minutely lower ATP hydrolysis than did its parent Y55 strain. Apparently, several different sources of acidity are involved in the glucose-induced acidification (including extrusion of organic acids); in fact, contrary to the general belief, the H(+)-ATPase may play a minor role in this process in some strains.
Biochem Mol Biol Int
· 1998 Dec · PMID 9861450
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In this study, we investigated the effect of chronic alcohol ingestion on the interplay between the receptor-bound basic fibroblast growth factor (bFGF-R) and the expression of cyclin-dependent kinase (Cdk2) in buccal mu...In this study, we investigated the effect of chronic alcohol ingestion on the interplay between the receptor-bound basic fibroblast growth factor (bFGF-R) and the expression of cyclin-dependent kinase (Cdk2) in buccal mucosa during ulcer healing. Chronic ulceration was induced by a topical application of acetic acid to the buccal mucosa of rats maintained for 5 weeks on alcohol-containing or control liquid diet. In both groups, the ulcer healing was accompanied by an increase in buccal mucosal expression of bFGF and Cdk2. In the control group, the ulcer healed within 10 days and maximum induction in bFGF (2.6-fold) and Cdk2 (2.4-fold) occurred by the 2nd day of healing. In contrast, the alcohol diet group showed a marked delay in ulcer healing (14 days), associated with the shift in maximum of bFGF and Cdk2 expression to the 4-6th day, and the values were reduced by 35 to 38%. The findings show that chronic alcohol ingestion exerts detrimental effect on the signaling events initiated by bFGF-receptor activation and propagated by Cdk2 that propels the cell cycle progression essential for rapid mucosal repair.
Biochem Mol Biol Int
· 1998 Dec · PMID 9861449
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The aim of the present study was to investigate whether the brush border membrane ferric reductase activity of Caco-2 cells is modulated during cell differentiation. The ferric reductase activity was determined in whole...The aim of the present study was to investigate whether the brush border membrane ferric reductase activity of Caco-2 cells is modulated during cell differentiation. The ferric reductase activity was determined in whole cells and isolated microvillous membranes at different stages of cell differentiation by measuring the amount of Fe3+ reduced during the incubation time. Our results indicated that the ferric reductase activity decreased in fastly growing cells and reactivated in postconfluent cells in contrast to the alkaline phosphatase and sucrase activities which were progressively expressed during differentiation as conventional indicators of cell maturity. The lowest ferric reductase activity was found in cells at the log phase of proliferation, while freshly seeded or highly differentiated cells had significantly higher enzyme activities. Cells grown under serum-free conditions had similar ferric iron reduction rates as cells propagated under standard conditions. Reagents or hormones affecting cell metabolism through different pathways had no significant effect on this transplasma membrane redox system.
Biochem Mol Biol Int
· 1998 Dec · PMID 9861448
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Interactions of tetracycline with bovine serum albumin (BSA) were studied by fluorescence quenching and circular dichroism (CD) analysis. The binding isotherm exhibited at least 13 tetracycline binding sites on the album...Interactions of tetracycline with bovine serum albumin (BSA) were studied by fluorescence quenching and circular dichroism (CD) analysis. The binding isotherm exhibited at least 13 tetracycline binding sites on the albumin molecule. Amongst these, four were found to be high affinity sites and the remainder were loose sites. The Scatchard analysis demonstrated the binding constant and capacity of BSA to be 4.6 x 10(6) liters/mole and 3.6, respectively. The CD data revealed a significant decrease in the mean residue ellipticity (MRE), indicating alterations in the protein helicity. A reduction of 20% in the alpha-helical content of the albumin was noted at higher levels of tetracycline in the presence of Cu (II) ions. Thus the strong in vitro interactions of tetracycline with albumin resulted in conformational changes in its globular structure and insinuate potential health risk due to possible macromolecular damage, under physiological conditions, from the formation of tetracycline/Cu(II) complexes.
Biochem Mol Biol Int
· 1998 Dec · PMID 9861447
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The transcription of OP2 encoding enzymes for m-toluate catabolism on the Pseudomonas putida TOL plasmid is activated by basal-level XylS protein in the presence of m-toluate or by overproduced XylS protein in the absenc...The transcription of OP2 encoding enzymes for m-toluate catabolism on the Pseudomonas putida TOL plasmid is activated by basal-level XylS protein in the presence of m-toluate or by overproduced XylS protein in the absence of m-toluate. In this study, in vivo dimethyl sulfate (DMS) footprinting was performed to understand the mechanism of transcriptional regulation of OP2 promoter by XylS. In the presence of overproduced XylS without m-toluate, several protected nucleotides were observed, indicating the binding of RNA polymerase to DNA. However, the protection was canceled upon addition of m-toluate. These results suggest that RNA polymerase is retained by XylS on the OP2 promoter in the absence of inducer, and is released by m-toluate binding to XylS, concomitant with transcription.
Biochem Mol Biol Int
· 1998 Dec · PMID 9861446
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We examined effects of pravastatin on age-related changes in mitochondrial function in rats. Decline in the activity of complex I of the mitochondrial electron transport chain was observed in diaphragm and psoai major in...We examined effects of pravastatin on age-related changes in mitochondrial function in rats. Decline in the activity of complex I of the mitochondrial electron transport chain was observed in diaphragm and psoai major in rats aged 35 and 55 weeks, and that of complex IV in rats aged 55 weeks. Pravastatin accelerated significantly age-related decline in the activity of complex I of diaphragm mitochondria, though pravastatin did not show significant effect on normally observed age-associated decline in the activities of complex IV of psoai major and diaphragm mitochondria. Aging effect on mitochondrial respiratory function was not observed on heart muscle and liver in rats up to 55 weeks old, and pravastatin did not effect significantly heart and liver mitochondrial respiratory function. From these results, careful clinical examination on respiratory muscle function should be necessary in patients treated with pravastatin particularly in elderly patients.
Frändberg PA, Doufexis M, Kapas S
… +1 more, Chhajlani V
Biochem Mol Biol Int
· 1998 Dec · PMID 9861445
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To delineate domains essential for G-protein coupling in melanocortin 1 receptor (MC1R), we mutated polar and basic residues to alanine at eleven positions in the putative third intracellular loop and determined conseque...To delineate domains essential for G-protein coupling in melanocortin 1 receptor (MC1R), we mutated polar and basic residues to alanine at eleven positions in the putative third intracellular loop and determined consequent changes in the ligand binding and generation of second messenger cAMP. Results demonstrate that ligand binding affinity was not affected by any of the mutations. However, every mutant displayed reduced functional response as compared to the wild type receptor. Replacement of residues (K226, R227, Q228, R229, H232, Q233 and K238) present in second half of third intracellular loop resulted in an almost complete loss of functional response. The results have demonstrated that the amino acid residues present in C-terminal portion of third intracellular loop of MC1R are involved in coupling to G-protein and that a region of four amino acids, K226-R227-Q228-R229 is essential for coupling of MC1R to G-protein.
Nomura M, Takihara Y, Abdul Motaleb M
… +3 more, Horie K, Higashinakagawa T, Shimada K
Biochem Mol Biol Int
· 1998 Dec · PMID 9861444
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The rae28 gene, a mouse homologue of the Drosophila polyhomeotic gene, is involved in the maintenance of the transcriptional repression states of Hox genes. In this study we synthesized the glutathione S transferase-RAE2...The rae28 gene, a mouse homologue of the Drosophila polyhomeotic gene, is involved in the maintenance of the transcriptional repression states of Hox genes. In this study we synthesized the glutathione S transferase-RAE28 (GST-RAE28) fusion protein and examined sequence-specific DNA binding activity in the RAE28 protein by using the selected and amplified binding site method. After five rounds of enrichment, the eluted DNAs were amplified, cloned and sequenced. The sequences of individual oligonucleotides included the following consensus sequences; 5'-ACCA-3', 5'-ACCCA-3', 5'-CTATCA-3' and 5'-TGCC-3'. The oligonucleotides including these consensus sequences were show to have significant affinity with the GST-RAE28 fusion protein. The RAE28 protein was recently shown to form multimeric protein complexes with other members of mouse Pc-G proteins in the nucleus. These findings strongly suggest that the RAE28 protein constitutes a sequence-specific DNA binding domain in multimeric Pc-G protein complexes.
Pietta P, Simonetti P, Gardana C
… +3 more, Brusamolino A, Morazzoni P, Bombardelli E
Biochem Mol Biol Int
· 1998 Dec · PMID 9861443
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Flavonoids are described to exert a large array of biological activities, which are mostly ascribed to their radical-scavenging, metal chelating and enzyme modulation ability. Most of these evidences have been obtained b...Flavonoids are described to exert a large array of biological activities, which are mostly ascribed to their radical-scavenging, metal chelating and enzyme modulation ability. Most of these evidences have been obtained by in vitro studies on individual compounds and at doses largely exceeding those dietary. Little is known about a possible relationship between rate and extent of the absorption and modifications of plasma antioxidants. To elucidate this aspect, human volunteers were supplemented with single doses of green tea catechins in free (Greenselect) or phospholipid complex form (Greenselect Phytosome) equivalent to 400 mg epigallocatechingallate (EGCg). EGCg was chosen as biomarker for green tea catechin absorption, and its time course plasma concentration was correlated to the subsequent percent variations of plasma ascorbate, total glutathione, alpha-tocopherol, beta-carotene and Total Radical Antioxidant Parameter (TRAP). Green tea catechins were absorbed more extensively when administered as phospholipid complex rather than as free catechins. Single dose intake of both forms of catechins produced a transient decrease (10-20%) of plasma ascorbate and total glutathione and an increase of plasma TRAP (16-19%). These variations were consistent with the plasmatic levels of EGCg, ascorbate and total glutathione.