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971.
Molecular comparison of<Emphasis Type="Italic"> waxy</Emphasis> null alleles in common wheat and identification of a unique null allele 总被引:3,自引:0,他引:3
Saito M Konda M Vrinten P Nakamura K Nakamura T 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2004,108(7):1205-1211
PCR selection markers for the identification of null waxy alleles were used to screen for waxy mutations in 168 common wheat cultivars. In all cultivars where the Wx-B1 protein was absent, the Wx-B1 allele was identical to the previously identified mutation carried by Kanto 107. Although most cultivars missing the Wx-A1 protein also carried the same Wx-A1 mutation as found in Kanto 107, all of the Turkey Wx-A1 mutants produced a different PCR fragment, implying the presence of a different mutation. Sequencing of this fragment indicated the mutation, which consisted of a 173-bp insertion in an exon, was in a different location than the previously identified Wx-A1 mutation. An 8-bp duplication of the Wx-A1 sequence flanked each end of the insertion, and an element with reverse complementary sequences was present at both ends of the insertion. These structures correspond with the features of class II transposable elements. Hence, the Turkey null Wx-A1 mutation was likely caused by the movement of a transposon, and this spontaneous mutation appears to be present in a limited geographical area.Communicated by C. Möllers 相似文献
972.
The cys-cys (C-C) chemokine ligand 21 is a member of the C-C chemokines that constitute a group of heparin-binding cytokines with a pattern of four or six conserved cysteines. The CCL21 is known to be expressed in secondary lymphoid tissues, however it has rarely been reported for the expression on peripheral lymphatic vessels in somatic tissue. Here we investigated the expression of CCL21 on lymphatic vessels identified by anti-desmoplakin in uninflamed and inflamed human gingiva. In uninflamed tissue the expression of CCL21 was detected on lymphatic vessels in gingiva. In uninflamed gingiva the expression of CCL21 was detected on all lymphatic capillaries of the mucosal connective tissue papillae. There were two types of collecting lymphatic vessels in the lamina propria mucosae expressing CCL21 strongly or very weakly. In inflamed gingiva no expression of CCL21 was detected on lymphatic vessels. In all tissue sections no blood vessels expressing CCL21 were observed. These results may suggest that the expression of CCL21 is predominantly induced in the peripheral lymphatic endothelium of the uninflamed mucosal microcirculation, and that under inflamed conditions a reduction of CCL21 occurs in lymphatic endothelium. 相似文献
973.
A method for positional cloning of the Bacillus subtilis genome was developed. The method requires a set of two small DNA fragments that flank the region to be copied. A 38-kb segment that carries genes ppsABCDE encoding five enzymes for antibiotic plipastatin synthesis and another genome locus as large as 100 kb including one essential gene were examined for positional cloning. The positional cloning vector for ppsABCDE was constructed using a B. subtilis low-copy-number plasmid that faithfully copied the precise length of the 38-kb DNA in vivo via the recombinational transfer system of this bacterium. Structure of the copied DNA was confirmed by restriction enzyme analyses. Furthermore, the unaltered structure of the 38-kb DNA was demonstrated by complementation of a ppsABCDE deletion mutant. 相似文献
974.
A fusion protein consisting of streptavidin and firefly luciferase was constructed to establish an accurate measuring technique of local ATP concentration. The fusion protein retained the binding ability of streptavidin and enzymatic activity of luciferase. Also, it could detect the concentration of antigens and could determine nanomolar concentrations of ATP in its fixed form via interactions with biotin-conjugated antibodies. 相似文献
975.
Oku Y Ohtaki A Kamitori S Nakamura N Yohda M Ohno H Kawarabayasi Y 《Journal of inorganic biochemistry》2004,98(7):1194-1199
Cytochrome P450 from thermoacidophilic crenarchaeon, Sulfolobus tokodaii strain 7 (P450st) has been expressed in Escherichia coli and purified at high homogeneity. P450st was crystallized in an orthorhombic system with the space group P2(1)2(1)2(1) and cell dimensions of a=53.6 A, b=55.1 A, and c=130.9 A, and the structure was determined at a 3.0 A resolution. The final R-factor was 0.194 (Rfree=0.235). Structural comparison with cytochrome P450 from S. solfataricus (CYP119) suggests that the region composed of the F to G helices and the Cl- binding site is responsible for the affinity for a ligand coordinating heme iron. Direct electrochemistry of P450st in a didodecyldimethylammonium bromide (DDAB) film on a plastic formed carbon (PFC) electrode has also been demonstrated. A quasi-reversible redox response has been observed even at elevated temperatures of up to 80 degrees C. 相似文献
976.
Ohtaki H Dohi K Yofu S Nakamachi T Kudo Y Endo S Aruga T Goto N Watanabe J Kikuyama S Shioda S 《Regulatory peptides》2004,123(1-3):61-67
It has been reported that pituitary adenylate cyclase-activating polypeptide (PACAP) plays an important role in preventing neuronal cell death and is also a potent vasodilator. Cerebral hypotension and hypoperfusion during cerebral ischemia and neurodegenerative diseases are well known as some of the negative factors which aggravate neuronal cell death. Nevertheless, the effect of PACAP on the cerebral circulation was not understood well. Therefore, in the present study, we determined the mean arterial blood pressure (MBP), regional cerebral blood flow (rCBF) and cerebral oxygen content (pO2) in mice, and estimated the therapeutically useful doses of PACAP. Under barbiturate anesthesia, polyethylene tubes were inserted into mice to monitor MBP and to administer PACAP (5 x 10(-13)-5 x 10(-8) mol/kg) or vasoactive intestinal peptide (VIP; 5 x 10(-12) and 5 x 10(-9) mol/kg). Then, MBP, rCBF and cerebral pO2 were simultaneously measured in the mice. PACAP (5 x 10(-10)-5 x 10(-9) mol/kg) injections transiently decreased MBP, and cerebral pO2. PACAP (5 x 10(-8) mol/kg) injections produced a long-lasting potent decline of MBP, rCBF and cerebral pO2. Therefore, PACAP should be applied at low doses which do not influence the MBP and cerebral circulation to determine the therapeutically useful doses of PACAP for neuroprotection. 相似文献
977.
Plasma adrenomedullin concentration is increased in patients with peripheral arterial occlusive disease associated with vascular inflammation 总被引:2,自引:0,他引:2
Suzuki Y Horio T Hayashi T Nonogi H Kitamura K Eto T Kangawa K Kawano Y 《Regulatory peptides》2004,118(1-2):99-104
Adrenomedullin (AM), a potent vasodepressor, is known to have anti-atherosclerotic and anti-inflammatory effects. However, there is no information about its level in severe atherosclerotic diseases, such as peripheral arterial occlusive disease (PAOD). The present study investigated the plasma concentration of AM and several inflammatory parameters in 72 patients with and without PAOD. The plasma AM concentration in patients with PAOD was significantly higher than in those without PAOD. Its concentration had significant correlations with ankle-brachial index and Fontaine's stage. The plasma AM level also correlated with high sensitive C-reactive protein and interleukin-6. As an additional study, plasma levels of two forms of AM drawn from the femoral artery and saphenous vein were measured in 27 other subjects. Both mature and intermediate forms of plasma AM in the femoral artery and saphenous vein were higher in patients with PAOD than in those without PAOD. A significant step-up of the mature form of AM from the femoral artery to the saphenous vein was observed. Our findings indicate that the plasma AM concentration was elevated in patients with PAOD in proportion to the severity of the disease and associated with vascular inflammation. An increased production of AM in PAOD may play a protective role against advanced atherosclerosis with an inflammatory signature. 相似文献
978.
Gamma-D-Glutamyl-L-tryptophan (SCV-07) is a prospective medicine for the treatment of tuberculosis, according to the phase two clinical trial. Because gamma-D-glutamyl-L-tryptophan has several reactive groups in its molecule, consists of D- and L-amino acids, and is connected by gamma-glutamyl linkage, its chemical synthesis is complicated. An efficient enzymatic method to synthesize gamma-D-glutamyl-L-tryptophan from D-glutamine and L-tryptophan employing bacterial gamma-glutamyltranspeptidase was developed. The optimum reaction conditions were 50 mM D-glutamine, 50 mM L-tryptophan, and 0.2 U ml(-1) gamma-glutamyltranspeptidase, pH 9-9.5, and incubation at 37 degrees C for 5 h. After a 5 h incubation, 33 mM gamma-D-glutamyl-L-tryptophan was obtained, the conversion rate being 66%. The product was purified by Dowex 1 x 8 column and was considered to be gamma-D-glutamyl-L-tryptophan. 相似文献
979.
Morita N Iizuka K Okita K Oikawa T Yonezawa K Nagai T Tokumitsu Y Murakami T Kitabatake A Kawaguchi H 《American journal of physiology. Endocrinology and metabolism》2004,287(6):E1064-E1069
Contraction of skeletal muscle generates pressure stimuli to intramuscular tissues. However, the effects of pressure stimuli, other than those created by electricity or nerve impulse, on physiological and biochemical responses in skeletal muscles are unknown. The purpose of this study is to examine the effects of a pure pressure stimulus on metabolic responses in a skeletal muscle cell line. Atmospheric pressure was applied to L6 myoblasts using an original apparatus. Succinate dehydrogenase (SDH) activity was evaluated by colorimetric assay using tetrazolium monosodium salt. The amounts of 2-deoxy-[(3)H]glucose uptake and lactate release were measured. SDH activity was 2.6- to 2.9-fold higher in pressurized L6 cells than in nonpressurized L6 cells (P < 0.01), and 2-deoxy-[(3)H]glucose uptake was 2.2-fold higher (P < 0.001). In addition, the amount of released lactate decreased from 6.8 to 3.7 mumol/dish when pressure was applied (P < 0.001). In contrast, the intracellular lactate contents of the pressurized cells were higher than those of nonpressurized cells (P < 0.01). However, the total amount of released lactate and intracellular lactate was lower in the pressurized cells than in nonpressurized cells. These findings demonstrate that a pure pressure stimulus enhances aerobic metabolism in L6 skeletal muscle cells and raise the possibility that elevated intramuscular pressure during muscle activity may be an important factor in stimulating oxidative metabolic responses in skeletal muscles. 相似文献
980.
Watanabe S Nagashio Y Asaumi H Nomiyama Y Taguchi M Tashiro M Kihara Y Nakamura H Otsuki M 《American journal of physiology. Gastrointestinal and liver physiology》2004,287(6):G1175-G1181
Pancreatic stellate cells (PSCs) play a central role in development of pancreatic fibrosis. In chronic pancreatitis, pancreatic tissue pressure is higher than that of the normal pancreas. We here evaluate the effects of pressure on the activation of rat PSCs. PSCs were isolated from the pancreas of Wistar rat using collagenase digestion and centrifugation with Nycodenz gradient. Pressure was applied to cultured rat PSCs by adding compressed helium gas into the pressure-loading apparatus to raise the internal pressure. Cell proliferation rate was assessed by 5-bromo-2'-deoxyuridine (BrdU) incorporation. MAPK protein levels and alpha-smooth muscle actin (alpha-SMA) expression were evaluated by Western blot analysis. Concentration of activated transforming growth factor-beta1 (TGF-beta1) secreted from PSCs into culture medium was determined by ELISA. Collagen type I mRNA expression and collagen secretion were assessed by quantitative PCR and Sirius red dye binding assay, respectively. Application of pressure significantly increased BrdU incorporation and alpha-SMA expression. In addition, pressure rapidly increased the phosphorylation of p44/42 and p38 MAPK. Treatment of PSCs with an MEK inhibitor and p38 MAPK inhibitor suppressed pressure-induced cell proliferation and alpha-SMA expression, respectively. Moreover, pressure significantly promoted activated TGF-beta1 secretion, collagen type I mRNA expression, and collagen secretion. Our results demonstrate that pressure itself activates rat PSCs and suggest that increased pancreatic tissue pressure may accelerate the development of pancreatic fibrosis in chronic pancreatitis. 相似文献