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11.
IAA biosynthetic activity was examined in cultured carrot tissuestransformed with Agrobacterium tumefaciens harboring wild-type,aux or cyt Ti plasmids. In vitro IAAM hydrolaseactivities in tissues transformed with wild-type, and cytTi plasmids were 3.09 and 19.82 nmol/g proteins/30 min, respectively,but not detectable when aux Ti plasmids were used. Theactivity of IAA biosynthesis, determined by the incorporationof radioactivity into IAA in tissues fed with [14C]-tryptophan,was 34.13, 10.92 and 32.47 pmol/g fr wt/30 min in tissues transformedwith wild type, aux and cyt Ti plasmids, respectively.The incorporation of radioactivity into the IAAM fraction wasdetected only in the tissues transformed with wild type andcyt Ti plasmids. These results showed that the T-DNAencoded pathway of IAA biosynthesis was active in tissues transformedwith wild-type and cyth Ti plasmids, and that the activity ofIAA biosynthesis in those tissues was higher than that in tissuestransformed with the aux Ti plasmid. (Received March 16, 1988; Accepted July 31, 1988) 相似文献
12.
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14.
Keiko Mori Kazuho Hirata Masaru Kawabuchi Manabu Nakashima Takeshi Watanabe 《Immunogenetics》1991,33(2):101-107
A monoclonal antibody (mAb) TP-3 has been established by immunizing rats with the BALB/c mouse thymic epithelial cell line TEL-2. The TP-3 antigen is expressed on stroma cells of thymus, spleen, and lymph node in syngeneic BALB/c mice (H-2
d
). This antigen is also expressed at a low level on the cell surface of immature thymocytes, and at a high level on mature T and B cells. In allogeneic mice such as C57BL/6 (H-2
b
) or C3H (H-2
k
), no cells expressed the TP-3 antigen. Using H-2 congenic mice, reactivity with mAb TP-3 was found to map to a region of H-2D
d
L
d
or between D
d
and Qa, suggesting that TP-3 is a major histocompatibility complex (MHC) class I antigen. However, immunoprecipitation analysis indicated that this antigen is not identical to the classical mouse class I molecules in terms of molecular size, antigenicity, and tissue distribution. 相似文献
15.
Michiaki Morohashi Keiko Tsuchiya Takashi Mita Masaru Kawamura 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1991,161(1):69-72
Summary An inhibitory activity to (Na,K)ATPase was found in cell extracts of the brine shrimp, Artemia salina, irrespective of its developmental stages. Organic solvent extraction together with gas chromatographic analysis reveals that the inhibitory activity is due to long-chain, non-esterified fatty acids and their derivatives. Unsaturated fatty acids, especially with cis-configuration, are more effective in inhibition than saturated ones.Abbreviations ATPase
adenosine triphosphatase
- EDTA
ethylenediamine-tetraacetate
- TLC
thin-layer chromatography 相似文献
16.
Satoshi Takeo Reiko Tanonaka Kouichi Tanonaka Keiko Miyake Hideto Hisayama Norifumi Ueda Keiko Kawakami Hiromi Tsumura Shuichi Katsushika Yuzo Taniguchi 《Molecular and cellular biochemistry》1991,107(2):169-183
The present study was designed to induce massive accumulation of calcium in the myocardium and to evaluate the effect of calcium overload on myocardial contractile function and biochemical activity of cardiac subcellular membranes. Rats were treated with an oral administration of 500,000 units/kg of vitamin D3 for 3 consecutive days, and their hearts were sampled on the 5th day for biochemical analysis. On the 4th and 5th days, heart rate, mean aortic pressure, left ventricular systolic pressure and left ventricular dP/dt were significantly lowered in vitamin D3-treated rats, demonstrating the existence of appreciable myocardial contractile dysfunction. Marked increases in the myocardial calcium (67-fold increase) and mitochondrial calcium contents (24-fold increase) were observed by hypervitaminosis D3. Mitochondrial oxidative phosphorylation and ATPase activity were significantly reduced by this treatment. A decline in sarcolemmal Na+, K+-ATPase activity was also observed, while relatively minor or insignificant changes in calcium uptake and ATPase activities of sarcoplasmic reticulum were detectable. Electron microscopic examination revealed calcium deposits in the mitochondria after vitamin D3 treatment. The results suggest that hypervitaminosis D3 produces massive accumulation of calcium in the myocardium, particularly in the cardiac mitochondrial membrane, which may induce an impairment in the mitochondrial function and eventually may lead to a failure in the cardiac contractile function. 相似文献
17.
Development of fin-supports and fin-rays was observed in larval and juvenileChanos chanos, Chondrification of the caudal complex started at 4.70 mm SL. Ossification of the caudal elements started at 7.80 mm SL and was nearly completed at about 30 mm SL. Cartilaginous fusion of caudal elements, which occurs in hypurals of higher teleostean fishes but is not seen in lower teleosts, was observed between the neural arch of the preural centrum 1 and that of the ural centrum 1 via a small cartilage bridging the distal tips of the two arches. Caudal finrays began to develop at 6.60 mm SL, and an adult complement of principal rays was attained at 7.35 mm SL. Dorsal and anal pterygiophore elements were first evident at 6.70 mm and 6.65 mm SL, respectively. All proximal radiais were formed at 8.15 mm SL in both fins. Formation of dorsal and anal fin-rays started simultaneously at 8.60 mm SL, and adult fin-ray complements were attained at 10,00 mm and 10.70 mm SL, respectively. In the pectoral fin, the cleithrum, coraco-scapular cartilage and blade-like cartilage (fin plate) had already been formed at 4.65 mm SL. The mesocoracoid was observed to originate from the coraco-scapular cartilage and become detached from it in the course of ossification. Pectoral fin-ray formation started at 13.80 mm SL and was completed in number of rays at 20.00 mm SL. In the pelvic fin, the basipterygium was first evident at 13.00 mm SL. Pelvic fin-rays appeared at 13.80 mm SL and attained their adult count at 17.15 mm SL. 相似文献
18.
Glycolipids of human cell lines of colonic adenocarcinoma (Colo 205 and BM 314), gastric tumor (AZ 521 and KATO-III), and lung tumor (A 549) were studied by the immunohistochemical fluorescence technique, flow cytometric analysis and immunostaining on thin layer chromatoplates with antibodies against gangliotriaosylceramide (Gg3Cer), gangliotetraosylceramide (Gg4Cer), fucogangliotetraosylceramide (Fuc-Gg4Cer), blood group B active lipid, globopentaosylceramide (Gb5Cer) and lactoneotetraosylceramide (nLc4Cer). Anti-nLc4Cer antibody was the only antibody which reacted with all the tumor cell lines used. The glycolipid fractions of each cell line separated by Iatrobeads column chromatography were immunostained with the six antibodies mentioned above on thin layer plates. The presence of nLc4Cer was detected in all cell lines. On the other hand, Gg4Cer was detected in gastric tumor cell lines, and Gg3Cer was detected in AZ 521. Based on these results, the tumor cell lines were analyzed by flow cytometry using anti-nLc4Cer antibody. About 70% of total cells in each cell line were separated as nLc4Cer-expressing cells. The present findings, together with the occurrence of nLc4Cer in ascitic fluids of cancer patients (Taki, T., Kojima, S., Seto, H., Yamada, H., & Matsumoto, M. (1984) J. Biochem. 96, 1257-1265), suggest that nLc4Cer may be a tumor-associated lipid. 相似文献
19.
T Taki H Kimura S Gasa M Nakamura M Matsumoto 《The Journal of biological chemistry》1985,260(10):6219-6225
A major glycosphingolipid in rat bone marrow cells was purified, and its structure was studied. The glycolipid was found to exhibit blood group B activity by the hemagglutination inhibition test. The structure was determined to be (formula; see text) by studies of nuclear magnetic resonance, sequential hydrolysis by exoglycosidases, linkage analysis of methylated sugars by gas chromatography-mass spectrometry, and immunological tests. The blood group B active glycolipid was detected not only in the bone marrow cells but also in spleen, thymus, and rat ascites hepatoma AH 7974F cells. Besides the glycolipid, gangliotriaosylceramide, gangliotetraosylceramide, and fucogangliotetraosylceramide were commonly detected in these cells. The similarity between the glycolipid species on the cell surfaces of the immunocytes and the tumor cells is discussed with the respect to an escape mechanism of the tumor cells from the immunosurveillance system. 相似文献
20.
Level of translatable messenger RNA coding for argininosuccinate synthetase in the liver of the patients with quantitative-type citrullinemia 总被引:2,自引:0,他引:2
Mariko Sase Keiko Kobayashi Yasushi Imamura Takeyori Saheki Kyoko Nakano Satoshi Miura Masataka Mori 《Human genetics》1985,69(2):130-134
Summary The translation activity of mRNA coding for argininosuccinate synthetase in total RNA extracted from the liver of three patients with quantitative-type citrullinemia was determined using a cell-free translation system. In two patients, the hepatic content of the enzyme was about 20% of the control value, whereas translatable mRNA level for the enzyme was similar to or slightly lower than those of control livers. In the third patient, the enzyme content was about 50% of the control value, and mRNA activity for the enzyme was low normal. These results indicate that at least in the first two patients, the decrease in the enzyme protein is due either to increased degradation of the enzyme or to decreased translation in the patient's liver. 相似文献