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71.
T Yano C Taura M Shibata Y Hirono S Ando M Kusubata T Takahashi M Inagaki 《Biochemical and biophysical research communications》1991,175(3):1144-1151
Monoclonal antibody YC10 showed specificity for the phosphorylated form of human, bovine and porcine glial fibrillary acidic proteins (GFAPs) and negligible reactivity towards the dephosphorylated form of the GFAPs. Analysis of species specificity and of the epitope, determined using synthetic phosphopeptides, indicated that this antibody recognized the local phosphorylation-site sequence Thr-phosphoSer-Ala-Ala-Arg-Arg (residues 7-12 of GFAP). Making use of this antibody we developed a non-radioactive method to measure protein kinase activities. After incubation of a protein kinase with non-radioactive ATP in ninety-six wells coated with the synthetic peptide Arg-Arg-Arg-Val-Thr-Ser-Ala-Ala-Arg-Arg-Ser-Cys (residues 3-13 of GFAP), the phosphorylated product was detected by using this mouse antibody and peroxidase-labeled goat anti-mouse IgG. This method proved to be equally as sensitive as the radioactive method for the measurement of protein kinase activities and was less affected by concentrations of ATP present in the reaction mixture. 相似文献
72.
M Ihara T Fukuroda T Saeki M Nishikibe K Kojiri H Suda M Yano 《Biochemical and biophysical research communications》1991,178(1):132-137
A competitive endothelin (ET) antagonist, BE-18257B, was isolated from the fermentation products of Streptomyces misakiensis. It is a novel cyclic pentapeptide, cyclo(-D-Glu-L-Ala-allo-D-Ile-L-Leu-D-Trp-), and binds to ETA receptors (ET-1 selective) in cardiovascular tissues, but not to ETB receptors (equally sensitive to isopeptides of ET family) in kidney, adrenal gland and cerebellum tissues. BE-18257B also antagonizes ET-1-induced vasoconstriction in rabbit iliac artery and pressor action in rats. Thus it is a selective ETA antagonist and should provide a valuable tool for elucidation of the pharmacological and pathophysiological roles of ET-1. 相似文献
73.
The behavior of chum slamon,Oncorhynchus keta, was studied using ultrasonic telemetry in the waters off the Okhotsk coast of Hokkaido from 1979 to 1981. Thirty-six adult
fish were outfitted with a 50 KHz ultrasonic transmitter provided with either a depth sensor, depth/illumination sensors,
or depth/ temperature sensors. Twenty-one of the experimental fish were used as controls and left intact. Of the remaining
fish, six had their sight destroyed, seven had their olfactory nerves severed or their nares filled with wax, one had both
senses destroyed, and one had a sham operation, but had only a shallow transverse cut made in the skin over the olfactory
nerves. Control fish and the fish with the sham operation initially swam in a horizontal zigzag pattern while fish with an
obliterated sense swam in a similar pattern but to a reduced extent. The horizontal and vertical speeds of the intact fish
were faster than those of the fish with a destroyed sense. Amplitude of vertical movements of the intact fish stretched from
surface to bottom, while fish with destroyed vision tended towards midwater. Fish without an olfactory sense tended to be
at the surface or near the bottom. Regular vertical movement would be effective in refreshing olfactory epithelia which might
become acclimated when exposed to one odor. The vertical movements can be found in the horizontal zigzag movements in coastal
and near shore migrations, as well as in the stream phase of homing. The zigzag movements, both horizontal and vertical, allow
the fish to sense the water masses and locate the correct tributary. 相似文献
74.
75.
A protein kinase C alpha (PKC alpha) cDNA confers increased phorbol ester binding activity to intact cells when transiently expressed in COS cells or expressed stably in transfected rat 3Y1 fibroblasts. A point mutant (PKC alpha K----R) of PKC alpha, where Lys368 at the putative ATP-binding site is replaced with Arg, confers enhanced phorbol ester binding activity to both transiently and stably expressed COS and 3Y1 cells, respectively. Like endogenous and exogenously expressed wild type PKC alpha, the mutant PKC alpha K----R is translocated from the cytosol to the particulate fraction when cells are treated with a phorbol ester, 12-O-tetradecanoylphorbol-13-acetate (TPA). On the other hand, the mutant PKC alpha K----R is not degraded when cells are treated with TPA, making a clear contrast to wild type PKC alpha; i.e. the mutant is resistant to TPA-mediated down-regulation. The mutant lacks kinase activity as expected, as judged by autophosphorylation and by a kinase assay using a peptide substrate, although the phorbol ester binding activity remains intact. These results suggest a link between the kinase activity of PKC alpha and the sensitivity to TPA-mediated proteolytic degradation. We propose that autophosphorylation of PKC alpha is a prerequisite for proteolytic cleavage associated with the down-regulation of PKC alpha. 相似文献
76.
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
77.
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
78.
The human ryanodine receptor gene: Its mapping to 19q13.1, placement in a chromosome 19 linkage group, and exclusion as the gene causing myotonic dystrophy 总被引:10,自引:1,他引:9 下载免费PDF全文
Alex E. MacKenzie Robert G. Korneluk Francesco Zorzato Junichi Fujii Michael Phillips David Iles B Wieringa Suzanne Leblond Jane Bailly Huntington F. Willard Catherine Duff Ronald G. Worton David H. MacLennan 《American journal of human genetics》1990,46(6):1082-1089
The recent cloning of cDNA encoding the Ca++ release channel (ryanodine receptor) of human sarcoplasmic reticulum has enabled us to use somatic cell hybrids to localize the ryanodine receptor gene (RYR) to the proximal long arm of human chromosome 19. Studies with additional hybrids containing deletions or translocations in chromosome 19 enabled us to localize RYR to 19q13.1 in a region distal to GPI/MAG and proximal to D19S18/DNF11. On the basis that the myotonic dystrophy (DM) locus maps near this region and that myotonia could result from a defect in the ryanodine receptor, we examined the linkage between the DM locus and RYR. Our results, showing several DM-RYR recombinants, rule out an RYR defect as the cause of DM. However, localization of RYR to a region of human chromosome 19 which is syntenic to an area of pig chromosome 6 containing the HAL gene responsible for porcine malignant hyperthermia supports the candidacy of RYR for this disorder. 相似文献
79.
80.
Hiroshi Kato Taiji Kato Yukio Sakazaki Yosuke Yamakawa Nobuyuki Naganawa Junichi Funabiki Takasumi Kato Ryo Tanaka Akira Masaoka Hidehiko Tsunooka 《Neurochemistry international》1982,4(5):419-426
BL191, a newly developed phosphodiesterase inhibitor, markedly potentiated a differentiation of neuroblastoma cell clones (Neuro2a, NS-20Y, and N1E115) induced by dibutyryl cyclic adensoine 3′:5′-monophosphate(dibutyryl cAMP) and prostaglandin E1 (PGE1). BL191 (1 mM) inhibited DNA synthesis more strongly when used together with PGE1 (0.5 μg/ml) and dibutyryl cAMP (0.5 mM) than papaverine (1.6 μg/ml) alone did. The inhibition rates of DNA synthesis were 72.5% for N1E-115, 75.3% for Neuro2a, and 82.5% for NS-20Y. After the treatment with BL191. PGE1, and dibutyryl cAMP for 48 h all of three cell lines became enlarged and flattened, and extended long processes. The specific activities of choline acetyl transferase (EC 2.3.1.9) of NS-20Y and dopamine β-hydroxylase (EC 1.14.17.1) of N1E-115 increased about 3-fold as compared to the controls. The tumorigenicities of Neuro2a and N1E-115 cells were decreased, but not of NS-20Y. These data suggest the heterogenous responsiveness in neuroblastoma cells to drug treatment. 相似文献