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Protein & Cell 2012年第10期3卷 762-768页

作者： Kai gong Fangfang Zhou Huizhe Huang yandao gong Long Zhang Department of Biological Sciences and Biotechnology Tsinghua UniversityBeijing 100084China Leiden University Medical Center Department of Molecular Cell BiologyLeidenthe Netherland Faculty of Basic Medical Sciences Chongqing Medical UniversityChongqing 400016China

We investigate the role of β-catenin signaling in the response of macrophage to lipopolysaccharide(LPS)using RAW264.7 *** rapidly stimulated cytosolic β-catenin accumulation.β-catenin-mediated transcription was showed to be required for LPS induced gene expression and cell ***,ERK activation-primed GSK3β inactivation by Akt was demonstrated to mediate the LPS induced β-catenin ***,our findings suggest that suppression of GSK3β by ERK stimulatesβ-catenin signaling therefore contributes to LPS induced cell migration in macrophage activation.

关键词： LPS ERK GSK3β β-catenin cell migration

In vitro biocompatibility of three chitosan/polycation composite materials for nerve regeneration

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Neural Regeneration Research 2008年第8期3卷 837-842页

作者： Zhenhuan Zheng Yujun Wei Gan Wang yandao gong Xiufang Zhang State Key Laboratory of Biomembrane and Membrane Biotechnology Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China

BACKGROUND：It has been reported that chitosan nerve conduits could support axon elongation and improve relevant function during in vivo nerve regeneration. OBJECTIVE： To investigate in vitro biocompatibility of three novel, chitosan/polycation composite materials for nerve regeneration in cultured mouse Schwann cells and PC12 cells. DESIGN, TIME AND SETTING： The observational, control experiments for nerve tissue engineering were performed at the Department of Biological Sciences and Biotechnology of Tsinghua University from August 2007 to January 2008. MATERIALS： Mouse Schwann cells were isolated from the sciatic nerve of 5–7-day-old BALB/C mice. PC12 cells were purchased from the American Type Culture Collection （ATCC, USA）. Chitosan was purchased from Tsingdao Haisheng Co., China. Poly-L-lysine hydrochloride （PLL）, polyethyleneimine （PEI） poly-L-ornithine hydrobromide （POR）, and S-100 antibody was purchased from Sigma Chemical Co., USA. Cell Counting Kit-8 （CCK-8） was purchased from Dojindo Chemical Co., Japan. METHODS： Three chitosan/polycation composite materials for nerve regeneration （PLL-0.25, PEI-0.25, and POR-0.25） were produced by blending chitosan with 0.25% （w/w） poly-L-lysine, polyethyleneimine, and poly-L-ornithine. Pure chitosan was utilized as the control. After 3 days of culture, the morphology of mouse Schwann and PC12 cells cultured on all substrates was observed with an inverted phase contrast microscope. Mouse Schwann cells were stained by immunofluorescence labeling S-100 protein and nuclei, followed by identification with a confocal laser-scanning microscope. The amount of proliferating mouse Schwann and PC12 cells was determined by CCK-8 after 1, 3, and 5 days in culture. The level of PC12 cell differentiation on all substrates was assessed by measuring neurite length at 1, 3, and 5 days after seeding. MAIN OUTCOME MEASURES： Morphology and amount of proliferation of mouse Schwann cells and PC12 cells cultured on chitosan and three polycation

关键词： biocompatibility chitosan nerve regeneration polycation

Simulation for the primary electronic donor of photosystem II in vitro

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Chinese Science Bulletin 2000年第10期45卷 914-920页

作者： PAN Jie ZHANG Chunxi gong yandao LI Liangbi ZHAO Nanming KUANG Tingyun Photosynthesis Research Center Institute of BotanyChinese Academy of SciencesBeijing 100093China National Laboratory of Biomembranes and Membrane Biotechnology Department of Biological Science and BiotechnologyTsinghua UniversityBeijing 100084China Laboratory of Optical Physics Institute of PhysicsChinese Academy of SciencesBeijing 100080China

Histidine coordinated to Chl a is a distinct characteristic of Chl a in vivo. By usinghistidine analogue of 1-methylimidazole (C4H6N2) and measuring the UV/vis absorption, CD and MCD spectra of the interaction between C4H6N2and Chl a in CCI4, we have obtained that: (i) In pure CCI4 solvent, Chl a molecule is in five-coordinate state, and two Chl a molecules form an asymmetric compact-dimer with strong coupling interaction. We propose that the two Chl a molecules are connected by two unequally coordinated Mg-O bonds (the two oxygen atoms come from the C=O of C131 keto and C17 ester, respectively); (ii) when the molar ratio of C4H6N2/Chl a is 0.5 or 1 (corresponding to 2Chl a #1C4H6N2 and 2Chl a ·2C4H6N2, respectively), significant changes have been observed in the absorption, CD and MCD spectra, which indicate that the Chl a remains in dimer form, but the coupling interaction between them reduces greatly. We postulate that C4H6N2 replaces the ligation of C=O of C17 ester and C131 keto to Mg atoms

关键词： photosynthesis Chl a histidine coordination P680 simulation spectroscopy research.

Amyloid beta-peptide worsens cognitive impairment following cerebral ischemia-reperfusion injury

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Neural Regeneration Research 2013年第26期8卷 2449-2457页

作者： Bo Song Qiang Ao Ying Niu Qin Shen Huancong Zuo Xiufang Zhang yandao gong Research Center of Stem Cells and Regenerative Medicine School of Medicine Tsinghua University State Key Laboratory of Biomembrane and Membrane Biotechnology School of Life Sciences Tsinghua University Institute of Neurology Disorders Yuquan Hospital Tsinghua University

Amyloid 13-peptide, a major component of senile plaques in Alzheimer＇s disease, has been implicated in neuronal cell death and cognitive impairment. Recently, studies have shown that the pathogenesis of cerebral ischemia is closely linked with Alzheimer＇s disease. In this study, a rat model of global cerebral ischemia-reperfusion injury was established via occlusion of four arteries; meanwhile, fibrillar amyloid [3-peptide was injected into the rat lateral ventricle. The Morris water maze test and histological staining revealed that administration of amyloid 13-peptide could further aggravate impairments to learning and memory and neuronal cell death in the hippocampus of rats subjected to cerebral ischemia-reperfusion injury. Western blot showed that phosphorylation of tau protein and the activity of glycogen synthase kinase 313 were significantly stronger in cerebral ischemia-reperfusion injury rats subjected to amyloid [3-peptide administration than those undergo- ing cerebral ischemia-repetfusion or amyloid 13-peptide administration alone. Conversely, the activ- ity of protein phosphatase 2A was remarkably reduced in rats with cerebral ischemia-reperfusion injury following amyloid 13-peptide administration. These findings suggest that amyloid 13-peptide can potentiate tau phosphorylation induced by cerebral ischemia-reperfusion and thereby aggravate cognitive impairment.

关键词： neural regeneration brain injury cerebral ischemia-reperfusion Alzheimer's disease amyloid 13-peptides tau proteins glycogen synthase kinase 313 protein phosphatase 2A phosphorylation grants-supported paper neuroregeneration

Endogenously generated amyloid β increases membrane fluidity in neural 2a cells

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Chinese Science Bulletin 2009年第3期54卷 394-398页

作者： NIU Ying SHENG BaiYang SONG Bo LIU LingLing ZHANG XiuFang ZHAO NanMing gong yandao State Key Laboratory of Biomembrane and Membrane Biotechnology Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China Medical School Tsinghua University Beijing 100084 China

The effect of endogenously generated amyloid β on membrane fluidity was investigated in Neural 2a cells stably expressing Swedish mutant amyloid precursor protein (APPswe). Membrane fluidity was studied by fluorescence polarizability using 1,6-Diphenyl-1,3,5-Hexatriene (DPH) as the fluorescence probe. It was found that the membrane fluidity in APPswe cells was significantly higher than that in its wild type counterparts. Alleviating the effect of amyloid β either by γ secretase activity inhibition or by amyloid antibody treatment decreased membrane fluidity, which indicated an important role of amyloid β in increasing membrane fluidity. Treatment using amyloid β channel blocker, tromethamine and NA4 suggested that channel formed by amyloid β on the cell membrane is a way through which amyloid β takes its membrane fluidizing effect.

关键词：膜流动性荧光极化老年痴呆症淀粉

The photodamage process of pigments and proteins of PSI complexes from Spinacia Oleracea L.

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Chinese Science Bulletin 2001年第21期46卷 1812-1816页

作者： WEI Jie YU Hui LI Liangbi KUANG Tingyun WANG Jushuo gong yandao ZHAO Nanming Laboratory of Photosynthesis Basic Research Institute of BotanyChinese Academy of SciencesBeijing 100093China Department of Biological Science and Biotechnology Tsinghua UniversityBeijing 100084 China

Purified PSI complexes from Spinacia Oleracea L. were exposed to the strong light (PFD=2300μmol m-2s-1) for various period. Along with the illumination the photo-damage process of pigments and proteins of PSI complexes was investigated using absorption, fluorescence, circular dichroism (CD) spectroscopy and SDS-PAGE. It was found from the optical absorption spectra that the maximal ab-sorbance of PSI complexes decreased and maximal peaks blue-shifted during the illumination, and the forth derivative spectra demonstrated that the absorbance decreasing at red region mainly resulted from the aborbance decreasing of the long wavelength Chla, implying that the long-wavelength Chla was readily to be bleached. The CD signals contributed by LHCI decreased more rapidly than other CD signals con-tributed by Chla and Carotenoid, indicating that the LHCI was more sensitive to light than core complexes. It was observed by SDS-PAGE that some small polypeptides of PSI complexes were damaged earlier than reaction

关键词： PSI pigment-protein complex photodamage LHCI absorption spectra CD spectra.

Phosphorylation of tau protein over time in rats subjected to transient brain ischemia

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Neural Regeneration Research 2013年第34期8卷 3173-3182页

作者： Bo Song Qiang Ao Zhen Wang Weiqiang Liu Ying Niu Qin Shen Huancong Zuo Xiufang Zhang yandao gong Institute of Neurology Disorders Yuquan Hospital Tsinghua University State Key Laboratory of Biomembrane and Membrane Biotechnology School of Life Sciences Tsinghua University Center for Advanced Materials and Biotechnology Research Institute of Tsinghua University in ShenzhenShenzhen High-Tech Industrial Estate Medical School Tsinghua University

Transient brain ischemia has been shown to induce hyperphosphorylation of the micro- tubule-associated protein tau. To further determine the mechanisms underlying these processes, we investigated the interaction between tau, glycogen synthase kinase （GSK）-313 and protein phos- phatase 2A. The results confirmed that tau protein was dephosphorylated during brain ischemia; in addition, the activity of GSK-3β was increased and the activity of protein phosphatase 2A was de- creased. After reperfusion, tau protein was hyperphosphorylated, the activity of GSK-3β was de- creased and the activity of protein phosphatase 2A remained low. Importantly, the interaction of tau with GSK-3β and protein phosphatase 2A was altered during ischemia and reperfusion. Lithium chloride could affect tau phosphorylation by regulating the interaction of tau with GSK-3β and pro- tein phosphatase 2A, and improve learning and memory ability of rats after transient brain ischemia. The present study demonstrated that it was the interaction of tau with GSK-3β and protein phos- phatase 2A, rather than their individual activities, that dominates the phosphorylation of tau in tran- sient brain ischemia. Hyperphosphorylated tau protein may play an important role in the evolution of brain injury in ischemic stroke. The neuroprotective effects of lithium chloride partly depend on the inhibition of tau phosphorylation during transient brain ischemia.

关键词： neural regeneration brain injury brain ischemia reperfusion microtubule-associated protein tau phosphorylation glycogen synthase kinase 3[3 protein phosphatase 2A lithium chloride grants-supported paper neuroregeneration

The mitochondrial function was impaired in APP knockout mouse embryo fibroblast cells

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Chinese Science Bulletin 2009年第10期54卷 1725-1731页

作者： SHENG BaiYang NIU Ying ZHOU Hui ZHOU Hui YAN JiaXin ZHAO NanMing ZHANG XiuFang gong yandao State Key Laboratory of Biomembrane and Membrane Biotechnology Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China Wuhan Institute of-Biological Products Wuhan 430060 China Medical School Tsinghua University Beijing 100084 China

The amyloid precursor protein (APP) is recognized as the source of Aβ, which plays an important role in Alzheimer’s disease. However, the biological function of APP is obscure. Previous studies showed that mitochondria could be a target of APP. In this work, APP knockout mouse embryo fibroblast (MEF) cells were used to test if APP plays any role in maintaining the mitochondrial function. As the result, APP knockout MEF cells (APP-/- cells) showed the abnormal mitochondrial function, including slower cell proliferation, lower mitochondrial membrane potential, lower intracellular ROS, higher mitochondrial membrane fluidity and lower cytochrome c oxidase activity than their wild-type counterparts. However, no change was found in the amount of mitochondria in MEF APP-/-cells.

关键词：胚胎成纤维细胞线粒体膜电位亚洲功能障碍小鼠细胞色素C氧化酶阿尔茨海默氏病应用程序

Amyloid precursor protein-mediated modulation of capacitive calcium entry

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Chinese Science Bulletin 2012年第35期57卷 4552-4559页

作者： MA Tuo NIU Ying ZHAO Chang SU ZuQi AO Qiang ZHANG XiuFang ZHAO NanMing gong yandao State Key Laboratory of Biomembrane and Membrane Biotechnology School of Life SciencesTsinghua UniversityBeijing 100084China Institute of Neurological Disorders Yuquan HospitalTsinghua UniversityBeijing 100084China

Alzheimer's disease(AD) is a progressive neurodegenerative *** the present study,the function of amyloid precursor protein(APP) in modulating capacitive calcium entry(CCE),a refilling mechanism for depleted intracellular calcium stores,was *** in neural 2a(N2a) cells stably expressing wild-type human APP was lower than in wild-type N2a cells,while CCE in APP knockout mouse embryonic fibroblast(MEF) cells was higher than in their wild-type *** demonstrate that wild-type APP depresses ***,using N2a cells transfected with C-terminal APP fragments,we show that these fragments anchored in the cell membrane play an important role in CCE depression.

关键词：淀粉样前体蛋白细胞内钙库电容调制蛋白质神经变性疾病阿尔茨海默氏病胚胎成纤维细胞

Circular Dichroism Analysis of the Effect of Metallic Ions on Structure of Collagen Molecules

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Tsinghua Science and Technology 1997年第1期2卷 78-81页

作者： Zhang Xufang gong yandao Dou Jiangang Shen Tianjie Zhao Nanming Department of Biological Science and Biotechnology State Key Labor atory of Biomembrane and Membr ane Biotechnology.Tsinghua UniversityBeijing 100084

Circular dichroism spectroscopy was used to study the effect of metallic ions such as Fe 3+,Al 3+and Ca 2+on the structure of collagen *** results showed the effect of the ions was similar to that of thermal denaturation but not as *** the basis of the obtained results,the mechanism used by the metallic ions to protect the biovalves from calcification may be explained as *** is the dominant component of the *** the biovalves with glutaraldehyde caused many amino acid residues in collagen molecules to cross *** leads to a decrease in the total positive charge in the collagen molecules and a relative surplus of free carboxyl *** trivalent metallic ions such as Fe 3+preferentially bound with negatively charged carboxyl groups of collagen molecules,which caused the superhelix of the collagen to be loose and *** improved the mechanical properties of the biovalve and neutralized surplus free carboxyl groups caused by the glutaraldehyde treatment,closed the sites where the Ca 2+was ***,it effectively protected the biovalves from calcification.

关键词： biomedical material biovalve collagen circular dichroism calcification