γ-干扰素诱导沙眼衣原体感染细胞酪氨酸激酶活化的研究

目的探讨IFN-γ诱导的沙眼衣原体感染细胞信号转导中酪氨酸激酶活化。方法采用IFN-γ作用于沙眼衣原体感染的McCoy细胞，用免疫印迹法检测信号蛋白酪氨酸激酶磷酸化的诱导活化，并应用酪氨酸激酶特异性抑制剂genistein拮抗IFN-γ诱导的酪氨酸激酶磷酸化。结果IFN-γ可以在短时间内引起沙眼衣原体感染细胞内的蛋白质酪氨酸激酶磷酸化。磷酸化程度随时间延长而改变，在15min时磷酸化程度最高，以后逐渐减弱。Genistein可抑制IFN-γ诱导的酪氨酸激酶磷酸化；随着浓度增大，抑制作用有所增加。结论IFN-γ诱导沙眼衣原体感染细胞酪氨酸激酶活化。     

枸杞多糖对四氯化碳和高糖致损大鼠肝细胞的作用

在四氯化碳(CCL₄)和高糖(HG)损伤的离体肝细胞模型上,研究CCL₄和HG对肝细胞葡萄糖激酶活性、钙离子浓度以及酪氨酸磷酸化水平的影响,并对枸杞多糖（LBP）的保护作用进行探讨.实验结果表明,CCL₄和HG均使肝细胞内葡萄糖激酶活性下降,Ca超载,并使细胞内酪氨酸磷酸化水平降低.LBP可以改善CCL4和HG引起的葡萄糖激酶活性和钙离子浓度的变化,以及CCL₄引起的胰岛素信号通路中的酪氨酸激酶活性的下降,但不能改善高糖引起的酪氨酸激酶活性的下降.由此认为,LBP对受到自由基直接损伤的肝细胞有较好的保护作用,而对高糖环境引起的肝细胞损伤不能完全修复,这可能与CCL₄和HG的作用机制不同有关.     

力经PSGL-1介导ERM蛋白ITAM-like序列上磷酸化位点的暴露

炎症反应阶段,P-选择素糖蛋白配体1(PSGL-1)与埃兹蛋白/根蛋白/膜突蛋白(ERM)的结合在招募脾酪氨酸激酶(Syk)并促进白细胞激活中发挥了重要作用.文中通过晶体结构分析发现,位于ERM蛋白非传统的免疫受体酪氨酸活化基序(ITAM-like)上的两个磷酸化位点(Y191和Y205)周围存在较大的空间位阻,这将阻碍其被Src家族激酶酪氨酸磷酸化继而招募Syk的过程.文中用拉伸分子动力学模拟的方法模拟力学环境下PSGL-1与根蛋白FERM结构域的相互作用,构象分析和残基溶剂可及表面积的变化都表明,经由PSGL-1传导的力学信号可以介导根蛋白ITAM-like序列上磷酸化位点Y205的暴露.文中结果揭示了一条经由PSGL-1胞内域激活Syk的力学信号通路,并且在原子层面上对PSGL-1/ERM/Syk之间的相互作用给予了阐释.     

肌营养不良蛋白dys参与调控Hippo信号通路

Hippo信号通路最早在黑腹果蝇中发现,现已被证明在哺乳动物中也是保守的.Hippo通路在器官发育和组织稳态中起着重要作用,Hippo信号通路异常与许多癌症的发生相关.Hippo信号通路依赖于核心激酶级联反应,磷酸化转录共激活因子Yorkie(Yki)进而调控下游靶基因的转录.尽管Wts是Hippo通路的关键激酶组分,...     

β淀粉样蛋白来源的扩散性配体对胞外信号调节激酶活性的影响

β淀粉样蛋白来源的扩散性配体降低细胞外信号调节激酶的磷酸化水平,免疫印迹结果显示在培养的海马神经元上,给予500 nmol/L的可溶性β淀粉样蛋白寡聚体,作用不同时间均降低了胞外信号调节激酶的磷酸化水平;可溶性β淀粉样蛋白寡聚体对细胞不同部位胞外信号调节激酶磷酸化水平影响不同,并且对细胞质、细胞膜、细胞核中胞外信号调节激酶磷酸化水平的影响在时间上呈现明显的差异;β淀粉样蛋白来源的扩散性配体通过突触外N-甲基-D-天冬氨酸受体影响胞外信号调节激酶信号通路,单独激活突触外的N-甲基-D-天冬氨酸受体或给予β淀粉样蛋白来源的扩散性配体后再激活突触外的N-甲基-D-天冬氨酸受体,胞外信号调节激酶的磷酸化水平均明显降低;水迷宫实验显示,转入淀粉样前体蛋白基因的小鼠要花更多时间找到目标平台,其海马胞外信号调节激酶磷酸化水平显著降低.     

Bruton酪氨酸激酶Btk的生物学特性研究进展

酪氨酸激酶Btk是非受体酪氨酸家族的成员,它由PH结构域、TH结构域、SH3结构域、SH2结构域和催化结构域5部分组成.Btk参与多种信号通路,对细胞的增殖、分化和凋亡起着重要的调控作用.Btk的突变可导致X连锁无丙种球蛋白血症,一直以来都是研究热点.笔者将围绕Btk的结构、功能、X连锁无丙种球蛋白血症的临床表现等方面的内容加以综述,着重探讨Btk参与B细胞信号通路、TLR信号通路和肥大细胞脱颗粒等过程的具体机制.     

EphB2受体N端结构域蛋白的纯化及其对胃癌细胞蛋白酪氨酸磷酸化的作用

EphB2受体在细胞生长、分化和信号转导过程中具有重要作用,为深入研究其在胃癌的信号转导中的作用及功能,检测了EphB2受体刺激胃癌细胞后的酪氨酸磷酸化的变化,利用Ni-NTA金属螯合亲和层析法将在E.coli中融合表达的重组蛋白EphB2受体的N端球状区进行纯化,并经Western印迹进行确证和ELISA方法检测该蛋白活性,得到纯度95%以上的融合蛋白,并有结合其天然配体的活性.EphB2受体诱导可以使胃癌细胞发生明显的蛋白质酪氨酸磷酸化的改变,即通过反向刺激其ephrinB配体引起了胃癌细胞信号转导通路中一些信号分子酪氨酸磷酸化的改变.     

酪氨酸蛋白激酶受体c-Met及靶点药物研究进展

酪氨酸激酶受体c-Met在细胞的代谢、分化以及死亡细胞的信号传导过程中起着重要的作用,其与配体结合,可活化其信号通路,参与胚胎发育、组织损伤修复以及肿瘤的发生和发展。因而,以酪氨酸激酶受体c-Met为靶点的抗肿瘤药物已经成为肿瘤研究中十分活跃的领域,为抗肿瘤治疗提供了新方法。     

人类病毒蛋白质磷酸化修饰位点的识别研究

蛋白质磷酸化翻译后修饰在病毒的复制和抑制宿主细胞功能方面发挥重要的作用。然而,利用实验的方法识别磷酸化位点既费时费力又耗财。因此基于蛋白质氨基酸序列发展一种机器学习方法对病毒蛋白磷酸化位点进行预测显得非常有必要。研究结合支持向量机提出识别病毒蛋白磷酸化位点的新方法。采用权重氨基酸成分和属性分组编码对病毒蛋白残基的氨基酸物理化学性质和序列信息进行特征提取,通过10倍交叉验证,丝氨酸、苏氨酸和酪氨酸磷酸化位点的预测准确率分别达到82.0%、85.8%和92.4%。运用该预测模型对丝氨酸残基磷酸化的激酶组进行分类评估,CMGC、AGC和CAMK激酶组的马氏相关系数分别达到69.3%、68.8%和68.2%。结果表明:构建的方法可以有效地预测激酶特异性的磷酸化位点。     

植物信号转导中的双组分体系

双组分体系是广泛存在于原核和真核细胞中的信号转导体系，主要由组氨酸激酶和反应调节子两个组分组成．双组分体系信号通路一般包括信号输入、组氨酸激酶自身磷酸化、反应调节子磷酸化和信号输出等环节．本文综述了近年来，双组分体系在植物中的研究进展．     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with     

Journal of Donghua University ( English Edition) Contents of Volume 31

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