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91.
Ca2(+)-calmodulin-dependent protein kinase II phosphorylates various types of non-epithelial intermediate filament proteins 总被引:3,自引:0,他引:3
T Tokui T Yamauchi T Yano Y Nishi M Kusagawa R Yatani M Inagaki 《Biochemical and biophysical research communications》1990,169(3):896-904
We have investigated the actions of Ca2(+)-calmodulin (CaM)-dependent protein kinase II on various types of non-epithelial intermediate filament proteins, vimentin, desmin, glial fibrillary acidic protein (GFAP) and neurofilament triplet proteins. Most of these filament proteins could serve as substrates. The effects of phosphorylation on the filamentous structure of vimentin were investigated in sedimentation experiments and by using electron microscopy. The amount of unassembled vimentin increased linearly with increased phosphorylation. However, the extent of the effect of phosphorylation on the potential to polymerize was also affected by the MgCl2 concentration, under conditions for reassembly. The actions of Ca2(+)-CaM-dependent protein kinase II on non-epithelial intermediate filaments under physiological conditions are given attention. 相似文献
92.
Inhibition of biological actions of big endothelin-1 by phosphoramidon 总被引:19,自引:0,他引:19
T Fukuroda K Noguchi S Tsuchida M Nishikibe F Ikemoto K Okada M Yano 《Biochemical and biophysical research communications》1990,172(2):390-395
Endothelin (ET)-1 and big ET-1 both caused contraction of isolated porcine coronary arteries, but the potency of big ET-1 was 1/100-1/200 that of ET-1. These responses were independent of the vascular endothelium. Phosphoramidon blocked the vasoconstriction caused by 30 nM big ET-1, but was ineffective on the action of 0.3 nM ET-1. Also in vivo, phosphoramidon had no effect on the ET-1-induced pressor actions, but blocked the pressor and airway-contractile responses to big ET-1 in rats and/or guinea pigs. Thus, it is likely that the vascular responses to exogenous big ET-1 are at least in part due to its conversion to ET-1 by a phosphoramidon-sensitive ET converting enzyme(s) in the vascular smooth muscle in vitro and in vivo. 相似文献
93.
94.
Catharanthine and akuammicine, together with ajmalicine and strictosidine, were isolated from a culture strain of Catharanthus roseus suspension cells. The biosynthetic capability of the cultured cells to produce akuammicine, catharanthine and vindoline was confirmed by feeding experiments with dl-tryptophan-[3-14C] to yield the radioactive alkaloids. 相似文献
95.
The physiological action of CCC for leaves of Kyoho grapes wasstudied. Leaves from the lower to upper positions of the primaryshoots and (primary) lateral shoots showed uneven photosyntheticactivities with peaks. The photosynthetic activity of each leaffrom both shoots was increased by treatment with CCC, whereasrespiratory activity was not affected with CCC. In the primaryshoots, CCC treatment increased the contents of chlorophylla and b in the leaves, but in the lateral shoots only chlorophyllb contents were increased. Dry weights of the leaves from thelateral shoots increased with CCC, but those of leaves locatedin the vicinity of nodes bearing the fruit clusters varied slightlyor were almost the same as the dry weight of non-treated leaves.Leaf thickness was increased by CCC and paralleled the variationin dry weight. The leaf area was decreased by CCC. (Received April 19, 1980; ) 相似文献
96.
97.
Hajime Tokuda Tsutomu Unemoto 《Biochemical and biophysical research communications》1981,102(1):265-271
The membrane potential generated at pH 8.5 by K+-depleted and Na+-loaded is not collapsed by proton conductors which, instead, induce the accumulation of protons in equilibrium with the membrane potential. The generation of such a membrane potential and the accumulation of protons are specific to Na+-loaded cells at alkaline pH and are dependent on respiration. Extrusion of Na+ at pH 8.5 occurs in the presence of proton conductors unless respiration is inhibited while it is abolished by proton conductors at acidic pH. The uptake of α-aminoisobutyric acid, which is driven by the Na+-electrochemical gradient, is observed even in the presence of proton conductors at pH 8.5 but not at acidic pH. We conclude that a respiration-dependent primary electrogenic Na+ extrusion system is functioning at alkaline pH to generate the proton conductor-insensitive membrane potential and Na+ chemical gradient. 相似文献
98.
pKJ1, a naturally occurring conjugative plasmid coding for toluene degradation and resistance to streptomycin and sulfonamides. 总被引:5,自引:1,他引:4 下载免费PDF全文
Pseudomonas sp. TA8 isolated by m-toluate enrichment from an aqueous sample metabolized toluene and m- and p-xylenes via the meta cleavage pathway, and manifested specific resistance to streptomycin and sulfonamides. A variety of experiments revealed that the pKJ1 plasmid of about 150 megadaltons carried by TA8 specified both the toluene and xylene degradative function (the Tol function) and streptomycin/sulfonamide resistance. The deletion of a segment of pKJ1 (about 22 megadaltons) resulted in the loss of the Tol function. pKJ1 was not assigned to Pseudomonas incompatibility group P-1, P-2, P-3, or P-9. 相似文献
99.
Effects of preparations of saponin mixture and isolated ginsenosides, extracted from the root of Panax ginseng, on plasma corticotropin (ACTH) and corticosterone concentrations in rats were determined by the radioimmunoassay and competitive protein binding method. When ginseng saponin mixture was administered to rats intraperitoneally, plasma ACTH and corticosterone increased significantly 30, 60 and 90 min after the treatment. The kinetic pattern of the increase in plasma ACTH was almost parallel to that in plasma corticosterone. Isolated ginsenoside, protopanaxadiol or protopanaxatriol glycoside, also increased plasma corticosterone. The ginseng-induced increase in plasma corticosterone was suppressed by pretreatment with dexamethasone. Thus the ginseng saponin was found to act on the hypothalamus and/or hypophysis primarily, and stimulated ACTH secretion which resulted in increased synthesis of corticosterone in the adrenal cortex. 相似文献
100.
The oligomers of bovine serum albumin were produced by controlled reaction with peroxidizing linoleic acid to examine their possible utility as calibration proteins insodium dodecyl sulfate-polyacrylamide gel electrophoresis. The polymerization was effected in reaction mixtures containing linoleic acid undergoing peroxidation in the presence of ascorbic acid, and conditions that yield soluble oligomers with a wide molecular weight distribution were established. The interaction of these soluble oligomers with sodium dodecyl sulfate exhibited a binding isotherm indistinguishable from that obtained with bovine serum albumin. Furthermore, sodium dodecy sulfate-polyacrylamide gel electrophoresis of the albumin oligomers conformed to the empirical relation of molecular weight to mobility that pertains to the use of these oligomers as standard molecular weight markers. 相似文献