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211.
A K Roy B Chatterjee W F Demyan T S Nath N M Motwani 《The Journal of biological chemistry》1982,257(13):7834-7838
Hypophysectomy is known to cause complete suppression of the hepatic synthesis alpha 2u-globulin. The effect of hypophysectomy on the synthesis of alpha 2u-globulin can be reversed by multiple hormone treatment. The role of pituitary growth hormone in the multihormonal regulation of alpha 2u-globulin in rat liver was examined in the hypophysectomized male rats with and without growth hormone supplementation. Daily treatment of hypophysectomized rats with 5 alpha-dihydrotestosterone, corticosterone, thyroxine, and growth hormone for 8 days caused about 80% recovery in the hepatic content of alpha 2u-globulin and its corresponding mRNA as determined by radioimmunoassay, in vitro translation, and liquid hybridization with a cloned cDNA probe. However, omission of growth hormone from the treatment regimen failed to raise hepatic alpha 2u-globulin and its mRNA to more than 5% of the normal control. The possible effect of growth hormone on the translation of the mRNA for alpha 2u-globulin was examined with cultured hepatocytes derived from growth hormone-deficient rats. Culture of these cells in the presence of growth hormone for 24 h did not turn on the synthesis of alpha 2u-globulin. These results indicate that growth hormone regulates the synthesis of alpha 2u-globulin by acting at a step antecedent to mRNA translation. 相似文献
212.
The use of spectrofluorimeter coupled to a reverse phase high performance liquid chromatography column permits selective detection of indole-3-acetic acid at the low picogram level. The value of the technique is demonstrated by the analysis of endogenous IAA in elongating shoots, xylem sap and callus of Douglas-fir. The data are also used to illustrate a procedure whereby the accuracy of chromatographic analyses can be verified within definable probability limits.Abbreviations GC-MS
combined gas chromatography-mass spectrometry
- HPLC
high performance liquid chromatography
- IAA
indole-3-acetic acid
- SEC
steric exclusion chromatography
- SICM
selected ion current monitoring
Technical Paper No. 5379 from the Oregon State University Agricultural Experiment Station 相似文献
213.
Progesterone receptors were determined in the cytosol from the ampulla, ampullaryisthmic junction and isthmus of rabbit fallopian
tube and uterus of estrus and pregnant rabbits. The receptor levels when compared among its various anatomical segments, were
the same in ampulla, isthums and uterus but maximum in ampullary-isthmic junction. Significant differences were observed in
mated animals at 14, 24, 34, 48, 70 and 144 h after coitus. The receptor concentrations in portions of the fallopian tube
showed no significant change between 14 and 24 h after coitus, except for a decrease in ampullary-isthmic junction at 24 h.
At 34 h the concentration of receptor further decreased in all parts of the tube. At 48 and 70 h after coitus, receptor concentrations
decreased gradually in ampulla and ampullary-isthmic junction, while isthmus showed a gradual increase. At 144 h, the receptor
concentration showed no further change in ampulla and ampullary-isthmic junction; however, isthmus showed a decline. The uterine
receptor concentration declined steadily from estrus till 70 h after coitus, however, it was increased at 144 h. The dissociation
constant (Kd) of cytosol receptor in all the tissues at estrus and during early pregnancy was found similar. The implications of these
changes in relation to the normal ovum transport have been correlated in this paper. 相似文献
214.
215.
Odile Colard Aline Kervabon Christian Roy 《Biochemical and biophysical research communications》1980,95(1):97-102
The adenylate cyclase activities of the rat liver plasma membrane were measured simultaneously with the incorporation of acyl chains into the membrane phospholipids using oleyl CoA, linoleyl CoA or arachidonyl CoA thioester. The basal, fluoride — and glucagon — stimulated adenylate cyclase activities were increased by the incorporation of linoleate into the plasma membrane phospholipids. Oleyl CoA did not alter the adenylate cyclase activities whereas arachidonyl CoA, at high concentration, decreased the adenylate cyclase activities. These data indicate a specific effect of phospholipid molecular species containing linoleate. 相似文献
216.
Barbara R. Hough-Evans Marcelo Jacobs-Lorena Michael R. Cummings Roy J. Britten Eric H. Davidson 《Genetics》1980,95(1):81-94
Comparative measurements are presented of the sequence complexity of the RNA stored in the eggs of two dipteran flies, Musca domestica and Drosophila melanogaster. The genome of Musca is about five times the size of the Drosophila genome and contains about 3.6 times as much single-copy sequence. As shown earlier, the interspersion of repetitive and single-copy sequence is of the short-period form in Musca, and is of the long-period form in Drosophila. The egg RNA complexities were determined by hybridization of excess RNA with radioactively labeled single-copy DNA. Complexity is expressed as the length (in nucleotides) of diverse single-copy sequence represented in the RNA. The complexity of the RNA of the Musca egg is about 2.4 x 107 nucleotides, and that of the Drosophila egg is about 1.2 x 107 nucleotides. The RNA of the Musca egg is similar to or very slightly lower in complexity than that of other egg RNAs, e.g., those of Xenopus and sea urchin. Compared to all previously measured egg RNAs, Drosophila egg RNA is low in sequence complexity. 相似文献
217.
Summary Protoplasts were isolated for the first time from cell suspensions ofNigella sativa. These were then cultured in media and observed at regular intervals. Different concentrations of auxin and kinetin were tried with success to obtain root from the callus tissues of the protoplasts. 相似文献
218.
A procedure was developed for the detection of 2′,3′-cyclic nucleotide 3′-phosphohydrolase in myelin. This assay was sufficiently sensitive to detect the low levels of 2′,3′-cyclic nucleotide 3′-phosphohydrolase in human erythrocytes. The 2′,3′-cyclic nucleotide 3′-phosphohydrolase of human erythrocytes was determined to be exclusively associated with the inner (cytosolic) side of the membrane. Leaky ghostsand resealed ghosts were assayed for 2′,3′-cyclic nucleotide 3′-phosphohydrolase, (Ca2+/Mg2+-ATPase, and acetylcholinesterase activity, and the 2′,3′-cyclic nucleotide 3′-phosphohydrolase profile is the same as that of the (Ca2+/Mg2+)-ATPase, an established inner membrane maker. 相似文献
219.
We have isolated a chorismate mutase bradytroph (leaky auxotroph) ofAnabaena sp. PCC 7119 (ATCC 29151) as a spontaneous 6-fluorotryptophan-resistant mutant. The decreased chorismate mutase activity resulted in the production of quantities of the phenylalanine and tyrosine that limited rate of growth. 3-Deoxy-d-arabino-heptulosonate 7-phosphate (DAHP) synthase activity in the mutant was elevated more than twofold over the wild-type activity, suggesting derepression of this enzyme. The physiological deregulation of DAHP synthase and the genetic-based deficiency of chorismate mutase promoted an elevated level of intracellular chorismate, which then overwhelmed the competitive inhibition of anthranilate synthase by tryptophan, resulting in the overproduction of tryptophan and indoleglycerolphosphate. The presence of exogenous serine increased the production of tryptophan at the expense of indoleglycerolphosphate. This indicated that the endogenous potential for increasing the amount of serine available for increased tryptophan production is limited. 相似文献
220.