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101.
Isolation and complete nucleotide sequence of the gene for bovine parathyroid hormone 总被引:7,自引:0,他引:7
The structure of the bovine parathyroid hormone (PTH) gene has been analyzed by Southern blot hybridization of genomic DNA and by nucleotide sequence analysis of a cloned PTH gene. In the Southern analysis, several restriction enzymes produced single fragments that hybridized to PTH cDNA suggesting that there is a single bovine PTH gene. The restriction map of the cloned gene is the same as that determined by Southern blot analysis of bovine DNA. The sequence of 3154 bp of the cloned gene has been determined including 510 bp and 139 bp in the 5' and 3' flanking regions, respectively. The gene contains two introns which separate three exons that code primarily for: (i) the 5' untranslated region, (ii) the pre-sequence of preProPTH, and (iii) PTH and the 3' untranslated region. The gene contains 68% A + T and unusually long stretches of 100- to 150-bp sequences containing alternating A and T nucleotides in the 5' flanking region and intron A. The 5' flanking region contains two TATA sequences, both of which appear to be functional as determined by S1 nuclease mapping. Compared to the rat and human genes, the locations of the introns are identical but the sizes differ. Comparable human and bovine sequences in the flanking regions and introns are about 80% homologous. 相似文献
102.
It has been suggested previously that Japanese larch ( Larix kaempferi ) exhibits characteristics of C4 photosynthesis. To further evaluate this suggestion, stable carbon isotope ratios were determined for leaf and bark tissue of Larix gmelini, L. kaempferi, L. laricina, L. Iyallii, L. occidentalis , and L. sibirica. All δ13 C values were more negative than –22‰. Short-term labeling with 14 CO2 showed that phosphoglyceric acid and other phosphorylated compounds were the first products of photosynthesis in L. sibirica. Both of these results strongly suggest that the initial fixation of atmospheric CO2 in these six Larix species is accomplished solely via the C3 photosynthetic pathway. 相似文献
103.
A high level of binding of [3H]methyltrienolone (R1881 = 17beta-hydroxy-17alpha-methyl-estra-4, 9, 11-trien-3-one) was found in cytosol prepared from adrenals of castrated male rats. Binding of [3H]R1881 was of high affinity (DK = 6.2 nM) and highly specific for androgens. The [3H]R1881 complex migrates at 7-9S on sucrose gradients in low ionic strength buffer and at 4-5S in buffer containing 0.4M KC1. All binding studies have been performed in parallel with rat ventral prostate and adrenal cytosol. The present data suggest the presence of an androgen binding component in rat adrenal tissue. 相似文献
104.
The energy-linked ATPase complex has been isolated from spinach chloroplasts. This protein complex contained all the subunits of the chloroplast coupling factor (CF1) as well as several hydrophobic components. When the activated complex was reconstituted with added soybean phospholipids, it catalyzed the exchange of radioactive inorganic phosphate with ATP. Sonication of the complex into proteoliposomes together with bacteriorhodopsin yielded vesicles that catalyzed light-dependent ATP formation. Both the 32Pi-ATP exchange reactions and ATP formation were sensitive to uncouplers such as 3-tert-butyl-5,2′-dichloro-4′-nitrosalicylanilide, bis-(hexafluoroacetonyl)acetone and carbonyl cyanide-p-trifluoromethoxyphenyl-hydrazone, that act to dissipate a proton gradient. The energy transfer inhibitors dicyclohexylcarbodiimide, triphenyltin chloride and 2-β-d-glucopyranosyl-4,6′-dihydroxydihydrochalcone were also effective inhibitors of both reactions. 相似文献
105.
Dana A. Procsal Helen L. Henry Ernest J. Friedlander Anthony W. Norman 《Archives of biochemistry and biophysics》1977,179(1):229-234
The biological activity of 1α,24R,25-trihydroxyvitamin D3 [1α,24R,25(OH)3D3] was elevated in comparison to the hormonally active form of vitamin D3, 1α,25-dihydroxyvitamin D3 [1α,25(OH)2D3], in the rachitic chick in terms of its ability to (a) stimulate intestinal calcium absorption, (b) mobilize bone calcium, (c) induce intestinal calcium binding protein, (d) modulate the level of enzyme activity of the renal 25-OH-D3-1-hydroxylase system, and (e) interact with the intestinal cystosol-chromatin receptor system for the 1α,25(OH)2D3 receptor system. In each of these assays, the relative ratio of activity of 1α,24R,25(OH)3D3 to 1α,25(OH)2D3was (a) 25–50, (b) ca. 20, (c) 10, (d) 50, and (e) 36%, respectively. 相似文献
106.
William F. Long Frank B. Williamson 《Biochemical and biophysical research communications》1982,104(2):363-368
Calcium ions potentiated heparin-modulated antithrombin III inhibition of amidolysis catalysed by thrombin. Potentiation by calcium ions of heparin-independent antithrombin III inhibition of thrombin activity appeared to contribute to this effect. These results suggest a complex modulatory role for calcium ions in proteinase-catalysed reactions influenced by anti-proteinases and glycosaminoglycans. 相似文献
107.
Marsha E. Daman Ron L. Batstone-Cunningham Robert E. Hardy Kilian Dill 《International journal of biological macromolecules》1983,5(6):371-373
13C-n.m.r. spectral data for 13C reductively methylated intact homozygous and heterozygous glycophorins A were compared with the 13C-n.m.r. spectral data for the 13C reductively methylated homozygous and heterozygous N-terminal glycopeptides derived from the trypsin digest of glycophorin A. The results indicate that pronounced aggregation of this glycoprotein in solution does not affect the structural differences that we have previously observed for glycophorins AM and AN at and/or near the N-terminal amino acid. Moreover, the data suggest that two structural states exist for glycophorin AM. 相似文献
108.
Takehiko Watanabe Yoshitaka Taguchi Yukihiko Kitamura Kenichiro Tsuyama Hirota Fujiki Hiroshi Tanooka Takashi Sugimura 《Biochemical and biophysical research communications》1982,109(2):478-485
The effects of various promoters in two-step carcinogenesis on the induction of histidine decarboxylase in the skin of mice was investigated. The potencies of various phorbol esters in inducing histidine decarboxylase activity were parallel with their tumor-promoting activities. Indole alkaloids such as dihydroteleocidin B and lyngbyatoxin A, which induced ornithine decarboxylase and promoted tumor development in the skin of mice with the same potency as 12-O-tetradecanoylphorbol-13-acetate (TPA), also induced histidine decarboxylase activity. These results suggest that histamine produced by this inducible histidine decarboxylase may play some role in tumor promotion. 相似文献
109.
Denise K. H. Chou Nemani Prasadarao Omanand Koul Firoze B. Jungalwala 《Journal of neurochemistry》1991,57(3):852-859
Monoclonal antibody HNK-1 reacts with a carbohydrate epitope present in proteins, proteoglycans, and sulfoglucuronylglycolipids (SGGLs). On high-performance TLC plates, SGGLs of the CNS from several species migrated consistently slower than those from the PNS, a result indicating possible differences in the structures. The structural characteristics of the major SGGL, sulfoglucuronylneolactotetraosylceramide (SGGL-1), from CNS was compared with those of SGGL-1 from PNS. Although the composition, sequence, and linkages of the carbohydrate moiety of the SGGL-1 species were identical, SGGL-1 from CNS contained mainly short-chain fatty acids, 16:0, 18:0, and 18:1, amounting to 85% of the total fatty acids, whereas SGGL-1 from PNS contained large proportions (59%) of long-chain fatty acids (greater than 18:0). These differences in the fatty acid composition accounted for the different migration pattern observed. The developmental expression of SGGLs and HNK-1-reactive proteins was studied in rat cerebral cortex between embryonic day (ED) 15 to adulthood. SGGLs in the rat cortex were maximally expressed around ED 19 and almost completely disappeared by postnatal day (PD) 20. This expression was contrary to their increasing expression in the cerebellum and sciatic nerve with postnatal development. Six to eight protein bands with a molecular mass of greater than 160 kDa were HNK-1 reactive in the rat cerebral cortex at different ages. The major HNK-1 reactivity to the 160-kDa protein band seen in ED 19 to PD 10 cortex decreased and completely disappeared from the adult cortex, whereas several other proteins remained HNK-1 reactive even in the adult. Western blot analyses of the neural cell adhesion molecules (N-CAMs) during development of the rat cortex with a polyclonal anti-N-CAM antibody showed that the major HNK-1-reactive protein bands were not N-CAMs. Between PD 1 and 10, 190-200-kDa N-CAM was the major N-CAM, and between PD 15 to adulthood, 180-kDa N-CAM was the only N-CAM present in the rat cortex. 相似文献
110.
Kohtaro Taniyama Masami Niwa Yasufumi Kataoka Kimihiro Yamashita 《Journal of neurochemistry》1992,58(4):1239-1245
Modulation of the gamma-aminobutyric acidB (GABAB) receptor-mediated response by protein kinase C (PKC) was examined with regard to inhibition by stimulation of the GABAB receptor of stimulation-evoked release of noradrenaline (NA) from slices of cerebellar cortex and of acetylcholine (ACh) from strips of ileum. 12-O-Tetradecanoylphorbol 13-acetate (TPA) potentiated the high K(+)-evoked Ca2+-dependent release of NA and ACh, but not the ouabain-evoked release, even in the presence of external Ca2+. The potentiating effect was antagonized by sphingosine, thereby suggesting that PKC participates in the exocytotic-vesicular release of neurotransmitters, but does not do so in case of a nonvesicular release. GABA inhibited the high K(+)-evoked release of NA and ACh, but not the ouabain-evoked Ca(2+)-independent release. The effect of GABA was mimicked by baclofen and was antagonized by phaclofen, thereby suggesting that stimulation of the GABAB receptor inhibits the vesicular but not the nonvesicular release of neurotransmitters. TPA suppressed the GABAB receptor-mediated inhibition of high K(+)-evoked release of NA and ACh. The effect of TPA was antagonized by sphingosine. These results indicate that stimulation of the GABAB receptor inhibits the stimulation-evoked Ca(2+)-dependent release of neurotransmitters and that activation of PKC suppresses the GABAB receptor-mediated response. 相似文献