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Shiaw-Der Yang Jen-Shin Song Yao-Tsung Hsieh Hui-Wen Liu Wen-Hsiung Chan 《Journal of Protein Chemistry》1992,11(5):539-546
The ATP·Mg-dependent protein phosphatase activating factor (Fa) has been identified and purified to near homogeneity from brain. In this report, as evidenced on SDS-polyacrylamide gel electrophoresis followed by autoradiography, factorFa has further been identified as a cAMP and Ca2+-independent brain kinase that could phosphorylate synapsin I, a neuronal protein that coats synaptic vesicles, binds to cytoskeleton, and is believed to be involved in the modulation of neurotransmission. Kinetic study further indicated that factorFa could phosphorylate synapsin I with a lowK
m
value of about 2 µM and with a molar ratio of 1 mol of phosphate per mole of protein. Peptide mapping analysis revealed that factorFa specifically phosphorylated the tail region of synapsin I but on a unique site distinct from those phosphorylated by Ca2+/calmodulin-dependent protein kinase II and cAMP-dependent protein kinase, the two well-established synapsin I kinases. Functional study further revealed that factorFa could phosphorylate this unique specific site on the tail region of synapsin I and thereby inhibit cross-linking of synapsin I with microtubules. The results further suggest the possible involvement of factorFa as a synapsin I kinase in the regulation of axonal transport process of synaptic vesicles via the promotion of vesicles motility during neurotransmission. 相似文献
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Dr. Jian Wen Chen Lanping Zhang Jiantao Song Fen Hwang Qinghua Dong Jian Liu Yumin Qian 《Current microbiology》1992,24(4):189-192
The glycoproteins and glycolipids from membranes of virulent strain Z and avirulent strain M ofMycoplasma hyopneumoniae have been compared. The proteins and the glycoproteins were identified by SDS-polyacrylamide gel electrophoresis and concanavalin A-biotin labeling, respectively. The membrane preparation contained approximately 34 protein bands with molecular weights between 20 KD and 100 KD. The concanavalin A-biotin system reacted with a glycoprotein of a molecular weight of approximately 28,000 from avirulent strain M and did not react with the correspondent band from virulent strain Z. The membrane glycolipids of both strains consisted of monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG), and the percentages of 160, 180, and 181 fatty acids comprised more than 80% of the total fatty acids of membrane glycolipids. The 180 fatty acid of MGDG in avirulent strain M was twofold higher than that of virulent strain Z. 相似文献
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The PCR technique can use protein-derived oligonucleotide sequences as primers to develop probes for screening recombinant libraries. Here we report a method with highly degenerate mixtures of oligonucleotides as primers for the PCR that eliminates the need to identify or isolate the DNA sequences derived by PCR. The method uses the pool of PCR-generated DNA sequences radiolabeled during the extension reaction as a probe, combined with highly stringent hybridization and wash conditions that permit only homologous sequences to hybridize and therefore target desired clones. This technique was used successfully to clone the receptor for tumor necrosis factor. 相似文献
56.
脂质过氧化对人红细胞膜脂流动性的影响 总被引:20,自引:3,他引:17
研究枯稀过氧化氢/高铁血红素体系所产生的烷基过氧自由基对红细胞的损伤。测定了脂质过氧化的产物——丙二脂的生成,并证明阿魏酸钠对脂质过氧化的抑制。荧光偏振的结果指出,膜脂过氧化以后降低了膜脂的流动性。人红细胞用5DSA和16DSA标记并用ESR检测膜脂流动性,结果表明,序参数S几乎没有发生变化,旋转相关时间τ值的增加证明膜脂过氧化以后,疏水尾部的物理状态发生了改变。经脂质过氧化以后,红细胞膜中的不饱和脂防酸的减少,可能是降低膜脂流动性的原因之一。 相似文献
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大斑啄木鸟取食行为的研究 总被引:4,自引:0,他引:4
大斑啄木鸟(Dendrocopos major)是左家地区的常见鸟类,对它的研究,国内有过一些报道。1990年4—5月,笔者对它的取食行为做了较为系统的观察,现整理报道如下。 相似文献
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