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Recent progress on the structure of Ser/Thr protein phosphatases

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Science china(Life Sciences) 2008年第6期51卷 487-494页

作者： WANG Baijing1,2. ZHANG Peng1 & wei {2.1 1 department of {2. and molecular biology, beijing normal university, beijing Key Laboratory, beijing 100875, china 2.School of Life Science, Changchun normal {12., Changchun 130032. china department of biochemistry and {2. biology Beijing Normal University Beijing Key Laboratory Beijing China School of Life Science Changchun Normal University Changchun China

PP1, PP2. and PP2., belonging to the PPP family of Ser/Thr protein phosphatases, participate in regulating many important physiological processes, such as cell cycle control, regulation of cell growth and division regulation, etc. The sequence homology between them is relatively high, and ter- tiary structure is conserved. Because of the complexity of the structure of PP2. and the diversity of its regulatory subunits, its structure is less well known than those of PP1 and PP2.. The PP2. holoen- zyme consists of a heterodimeric core enzyme, comprising a scaffolding subunit and a catalytic sub- unit, as well as a variable regulatory subunit. In this study, the subunit compositions, similarities and differences between the Ser/Thr protein phsphatases structures are summarized.

关键词： Ser/Thr phosphatases subunit composition similarities and differences crystal structure

哺乳动物中Kelch超家族蛋白的结构与功能

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生物化学与生物物理进展 2011年第3期38卷 210-217页

作者：肖枫宋宏涛魏群北京师范大学生命科学学院北京市基因工程药物与生物技术重点实验室北京100875

在不同生物体,如病毒、植物、真菌和哺乳动物中,几百种含Kelch构象的蛋白质已经被鉴定出来了,但大部分此类蛋白质的功能未知.而在哺乳动物中,已经有接近41种Kelch蛋白被报道.这些蛋白质在体内参与了很多重要的生理过程.根据Kelch蛋白的... 详细信息

在不同生物体,如病毒、植物、真菌和哺乳动物中,几百种含Kelch构象的蛋白质已经被鉴定出来了,但大部分此类蛋白质的功能未知.而在哺乳动物中,已经有接近41种Kelch蛋白被报道.这些蛋白质在体内参与了很多重要的生理过程.根据Kelch蛋白的域结构不同,把这些哺乳动物中的Kelch蛋白分成了三类(BTB/Kelch蛋白,只含有Kelch结构域的蛋白质,及含其他结构域的Kelch蛋白),并把其已知的功能大致划分为5类:介导蛋白质-蛋白质的相互作用、参与蛋白质降解、信号传导、胞外功能及其他等.另外还认为Keap 1的Kelch结构域其晶体结构应该是研究哺乳动物Kelch蛋白的一个很好的参考模型.

关键词： Kelch蛋白哺乳动物细胞形变蛋白质降解信号传导

Effects of calcineurin on LTP of rats in vivo

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Chinese Science Bulletin 2002年第6期47卷 476-479页

作者： luo Jie LOU Ailin wei {2. department of biochemistry and {2. biology Beijing Normal UniversityBeijing 100875China department of Physiology Institute of Clinical Medical Sciences China-Japan Friendship HospitalBeijing 100020China

Calcineurin (CN) is thought to play a role in the synaptic plastivity and long-term potentiation (LTP) in the hippocampus. Based on two LTP models in vivo, a specific inhibitor cyclosporin A (CsA) of CN was observed, which affected LTP in the hippocampal dentate gyrus of the rats. The results indicated that CsA blocked LTP induced by high frequency stimulation (HFS) partly, but it had no effect on the decrease of the onset and peak latency of population spikes (PS) except that it reduced the increase of the amplitude after HFS. On the other hand, CsA blocked LTP induced by ginsenosides (GSS) completely. It suppressed the GSS-enhanced amplitude of PS reversibly and blocked the decrease of the peak latency of PS induced by the GSS. These results suggest that the postsynaptic CN plays a role in the induction of LTP in the hippocampus of the rats.

关键词： calcineurin cyclosporin A hippocampus long term po-tentiation (LTP) ginsenosides.

Activities and properties of calcineurin catalytic domain

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Chinese Science Bulletin 2000年第15期45卷 1394-1399页

作者： Yang Shujie Zhang Li wei qun department of biochemistry and {2. biology Beijing Normal UniversityBeijing 100875China State Key Laboratory of Biomacromolecules Institute of BiophysicsChinese Academy of SciencesBeijing 100101China

Calcineurin (CN) is the only protein phosphatase known to be under the control of calcium (Ca2.) and calmodulin (CaM). The enzyme consists of two subunits, the catalytic A subunit of 61 ku (CNA) and a regulatory B subunit of 19 ku (CNB). In this study, we used PCR amplication to construct a truncation consisting of only the CNA catalytic domain. The truncation was induced by IPTG and expressed in E. coli. PNPP was used as a substrate to study the phosphatase activity of the CNA catalytic domain. The findings show that its activity is 2. times greater than CNA in the presence of CNB and CaM. The optimum reaction temperature for the CNA catalytic domain protein is 40℃, and the optimum reaction pH value is 8.0. Mn2. is still an effective activator for the CNA catalytic domain, but its activity is not controlled by Ca2.. In the presence of 6 mmol/L Mg2., adding either Ca2. or EGTA did not change the activity of the CNA catalytic domain.

关键词： calcineurin protein phosphatase catalytic domain activity enzyme property.

Quality-control method for the determination of biological activity of engineered calcineurin subunit B

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Science china(Life Sciences) 2016年第6期59卷 584-588页

作者： Xinchang Shi Huan Yang Li Xu Xiang Li Zongwen Huang Yudong Han qun wei Chunming Rao Key Laboratory of the Ministry of health for Research on Quality and Standardization of Biotech Products National Institutes for Food and Drug Control department of biochemistry and {2. biology Beijing Normal University Gene Engineering and Biotechnology Beijing Key Laboratory Haikou Qili Pharmaceutical CO. LTD.

The aim of this study was to establish a quality-control method for calcineurin subunit B(CNB) biological activity determinations. CNB enhances the p-nitrophenylphosphate(p NPP) dephosphorylating activity of calcineurin subunit A Δ316 mutant(CNAΔ316). A series of CNB concentrations were fitted to a four-parameter equation to calculate the corresponding p NPP maximum dephosphorylation rates. Values were calculated based on biological activity references using a parallel line method. The method was then validated for accuracy, precision, linearity, linear range, sensitivity, specificity, and robustness. The recovery results were greater than 98%. Intra-plate precision was 6.7%, with inter-plate precision of 10.8%. The coefficient of determination was greater than 0.98. The linear range was 0.05–50 μg m L?1, with sensitivity of 50 μg m L?1. Tested cytokines did not induce CNAΔ316 dephosphorylation of p NPP. The chosen CNAΔ316 concentration range did not affect activity determinations.

关键词： calcineurin subunit B biological activity method establishment method validation quality control

The repression of oncoprotein SET by the tumor suppressor p53 reveals a p53-SET-PP2. feedback loop for cancer therapy

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Science china(Life Sciences) 2023年第1期66卷 81-93页

作者： Han Yao Wenbin Xu Yajing Liu Zhijie Cao Jia Wen Mi Zhang zhen {2. Xiaojun Yan Zishan Jiao Zijing Zhang Jianyuan Chen Meng Zhang wei-Guo Zhu Donglai Wang State Key Laboratory of Medical molecular biology&{2. of Medical Genetics Institute of Basic Medical Sciences&School of Basic MedicineChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100005China department of Anatomy Histology and EmbryologySchool of Basic MedicineChina Medical UniversityShenyang 110122China department of biochemistry and {2. biology Shenzhen University School of MedicineShenzhen 518060China

The oncoprotein SET is frequently overexpressed in many types of tumors and contributes to malignant initiation and progression through multiple mechanisms,including the hijacking of the tumor suppressors p53 and *** aberrant SET represents a promising strategy for cancer ***,the mechanism by which endogenous SET is regulated in cancer cells remains largely ***,we identified the tumor suppressor p53 as a key regulator that transcriptionally repressed the expression of SET in both normal and cancer *** addition,p53 stimulated PP2. phosphatase activity via p53-mediated transcriptional repression of SET,whereby SET-mediated inhibition of PP2. was ***,targeting the interaction between SET and PP2. catalytic subunit(PP2.c)with FTY72. enhanced stress-induced p53 activation via PP2.-mediated dephosphorylation of p53 on threonine 55(Thr55).Therefore,our findings uncovered a previously unknown p53-SETPP2. regulatory feedback *** functionally potentiate this feedback loop,we designed a combined therapeutic strategy by simultaneously administrating a p53 activator and SET antagonist in cancer cells and observed a dramatic synergistic effect on tumor *** study reveals mechanistic insight into the regulation of the oncoprotein SET and raises a potential strategy for cancer therapy by stimulating the p53-SET-PP2. feedback loop.

关键词： p53 SET PP2. FTY72. feedback loop tumor suppression

The new Immunosuppressant, isogarcinol, binds directly to itstarget enzyme calcineurin, unlike cyclosporin A and tacrolimus

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The new Immunosuppressant, isogarcinol, binds directly to it...

Interaction of glycyrol with calcineurin A studied by spectroscopic methods and docking

中国生物化学与分子生物学会第十一次会员代表大会暨2.14年全国学术会议

作者： Juren Cen Mengqi Wang Guohua Jiang Yanxia Yin zhenyi Su Li Tong jing {2. YipengMa qun wei department of biochemistry and {2. biology Beijing Normal University Gene engineering and Biotechnology Beijing Key Laboratory

Isogarcinol, a bioactive polyisoprenylated benzophenone derivative isolated fromGarcinia mangostana L., has been shown previously to exert a strong inhibitory effect oncalcineurin and is thus a potential oral, low-toxicity immunomodulatory drug. In thepresent study, enzyme kinetic analysis showed that inhibition of calcineurin by isogarcinolwas competitive. F{2.rescence spectroscopy indicated that isogarcinol bound to *** titration calorimetry showed that binding was mainly driven by enthalpy,and was exothermic because the enthalpy change exceeded the entropy reduction. The interactionforce is either hydrogen bonding or Van der Waals forces. F{2.rescence resonanceenergy transfer and molecular docking experiments indicated that there were twopotential binding sites for isogarcinol in the catalytic domain of calcineurin. In summary,isogarcinol binds directly to calcineurin in vitro, unlike the classical calcineurin inhibitorscyclosporin A and tacrolimus.

关键词： isogarcinol calcineurin isothermal titration calorimetry fluorescences pectroscopy docking

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Interaction of glycyrol with calcineurin A studied by spectr...

Purification,characterization of a novel protease from cordyceps sinensis and determination of the cleavage site motifs using oriented peptide library mixtures

中国生物化学与分子生物学会第十届会员代表大会暨全国学术会议

作者： Liqin Peng Yao Qi hezhen {2. qun wei department of biochemistry and {2. biology Beijing Normal UniversityBeijing Key Laboratory

We have shown previously that glycyrol has an inhibitory effect on the immune response in mice by reducing calcineurin ***,we investigated the interaction of glycyrol with calcineurin A(CNA,catalytic A subunit of calcineurin) by spectroscopic methods and *** analyzing the fluorescence emission spectra of CNA with various concentration of glycyrol at 4℃,the binding constant (KA) and the number of binding sites(n) were calculated. For calculating thermodynamic parameters of interaction, KA at 2.℃was previously calculated to be 2.55(±0.17)×105 M-l(n=3,relative coefficient R>0.99).Then AH and

关键词： calcineurin glycyrol fluorescence spectroscopy circular dichroism docking

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Purification,characterization of a novel protease from cordy...