N-acetylatedα-synuclein(αSyn)has long been established as an intrinsically disordered protein associated with a dysfunctional role in Parkinson’s disease.In recent years,a physiologically relevant,higher order conf...N-acetylatedα-synuclein(αSyn)has long been established as an intrinsically disordered protein associated with a dysfunctional role in Parkinson’s disease.In recent years,a physiologically relevant,higher order conformation has been identified as a helical tetramer that is tailored by buried hydrophobic interactions and is distinctively aggregation resistant.The canonical mechanism by which the tetramer assembles remains elusive.As novel biochemical approaches,computational methods,pioneering purification platforms,and powerful imaging techniques continue to develop,puzzling information that once sparked debate as to the veracity of the tetramer has now shed light upon this new counterpart inαSyn neurobiology.Nuclear magnetic resonance and computational studies on multimericαSyn structure have revealed that the protein folding propensity is controlled by small energy barriers that enable large scale reconfiguration.Alternatively,familial mutations ablate tetramerization and reconfigure polymorphic fibrillization.In this review,we will discuss the dynamic landscape ofαSyn quaternary structure with a focus on the tetrameric conformation.展开更多
Self-association system of(R)-1,3-butanediol in dilute carbon tetrachloride(CCl4)solution is studied as a model of molecular association mixture.Analysis methods including FSMWEFA(fixed-size moving window evolving fac...Self-association system of(R)-1,3-butanediol in dilute carbon tetrachloride(CCl4)solution is studied as a model of molecular association mixture.Analysis methods including FSMWEFA(fixed-size moving window evolving factor analysis)combined with PCA(principal component analysis),SIMPLISMA (simple-to-use interactive self-modeling mixture analysis),and ITTFA(iterative target transformation factor analysis)are adopted to resolve infrared spectra of(R)-1,3-butanediol solution.Association number and equilibrium constant are computed.(R)-1,3-butanediol in dilute inert solution is determined as a monomer-trimer equilibrium system.Theoretical investigation of trimer structures is carried out with DFT(density functional theory),and structural factors are analyzed.展开更多
为了探讨多聚AFPⅢ的作用机制,从南极鱼Lycodichthys dearborni的多聚三型抗冻蛋白基因LD12 c DNA中克隆得到AFPⅢ的四聚体,命名为LD4,并构建真核表达质粒Tol2-actin-LD4-2A-EGFP。将表达质粒转染到斑马鱼细胞系ZF4中,发现LD4可以在ZF4...为了探讨多聚AFPⅢ的作用机制,从南极鱼Lycodichthys dearborni的多聚三型抗冻蛋白基因LD12 c DNA中克隆得到AFPⅢ的四聚体,命名为LD4,并构建真核表达质粒Tol2-actin-LD4-2A-EGFP。将表达质粒转染到斑马鱼细胞系ZF4中,发现LD4可以在ZF4中大量表达并且能够减少斑马鱼细胞在低温胁迫下的死亡率。通过对不同处理温度(28、18、10℃)下的WT、EGFP和LD4细胞进行转录组测序分析,找出26个表达差异转录因子,其中I3MB13、ZNF687b等表达上调,JUN、Cremb等表达下调,并且通过荧光定量PCR的验证。通过KEGG pathway分析发现,这些差异性基因主要参与细胞凋亡、细胞周期、增殖等调节通路。采用Annexin V-PE/7-AAD双染色法对3种不同温度下的WT、EGFP和LD4细胞进行细胞凋亡检测,结果显示,LD4在低温下与对照组相比凋亡率没有显著差异,说明LD4可能是通过其他通路而不是通过抑制细胞凋亡来抵御低温胁迫,这为LD4作用机制的进一步研究提供了理论基础。展开更多
目的探讨纯化的隐球菌抗原肽GMFDGLSGV二聚体、四聚体、八聚体重组蛋白激发细胞毒性T淋巴细胞(Cytotoxic T lymphocyte,CTL)免疫应答的能力,为新型隐球菌疫苗的研制打下基础。方法通过细胞增殖和细胞毒性实验,研究纯化的GMFDGLSGV单体...目的探讨纯化的隐球菌抗原肽GMFDGLSGV二聚体、四聚体、八聚体重组蛋白激发细胞毒性T淋巴细胞(Cytotoxic T lymphocyte,CTL)免疫应答的能力,为新型隐球菌疫苗的研制打下基础。方法通过细胞增殖和细胞毒性实验,研究纯化的GMFDGLSGV单体、二聚体、四聚体、八聚体重组蛋白刺激外周血单个核细胞(PBMC)产生的增殖反应和细胞毒活性,初步鉴定重组多聚体的免疫原性。结果10例HLA-A*0201阳性个体PBMC对八聚体的平均SI为37.4±3.07;增殖反应明显高于四聚体(平均SI为20.1±1.37)、二聚体(平均SI为14.1±1.06)、单体(平均SI为11.4±0.68)以及阴性对照(平均SI为1±0.10)引起的细胞增殖反应(P<0.01)。在抗原肽诱导的CTL细胞毒活性中,HLA-A*0201阳性个体PBMC对八聚体、四聚体、二聚体、单体及阴性对照组均表现不同程度的杀伤活性,平均活性分别为48.1±4.28、23.9±2.20、16.3±1.27、13.1±1.10、1.0±0.1(P<0.01)。结论本研究得到的重组优化八聚体具有较好的免疫原性,能有效刺激PBMC产生细胞增殖反应和细胞毒活性,为进一步开发有效的隐球菌疫苗打下了基础。展开更多
基金supported in part by Award No.18-7(to HRL)from the Commonwealth of Virginia’s Alzheimer’s and Related Diseases Research Award Fund,administered by the Virginia Center on Aging
文摘N-acetylatedα-synuclein(αSyn)has long been established as an intrinsically disordered protein associated with a dysfunctional role in Parkinson’s disease.In recent years,a physiologically relevant,higher order conformation has been identified as a helical tetramer that is tailored by buried hydrophobic interactions and is distinctively aggregation resistant.The canonical mechanism by which the tetramer assembles remains elusive.As novel biochemical approaches,computational methods,pioneering purification platforms,and powerful imaging techniques continue to develop,puzzling information that once sparked debate as to the veracity of the tetramer has now shed light upon this new counterpart inαSyn neurobiology.Nuclear magnetic resonance and computational studies on multimericαSyn structure have revealed that the protein folding propensity is controlled by small energy barriers that enable large scale reconfiguration.Alternatively,familial mutations ablate tetramerization and reconfigure polymorphic fibrillization.In this review,we will discuss the dynamic landscape ofαSyn quaternary structure with a focus on the tetrameric conformation.
基金the National Natural Science Foundation of Chinathe YellowRiver Water Conservancy Commission(Grant Nos.50239080 and 40271019)
文摘Self-association system of(R)-1,3-butanediol in dilute carbon tetrachloride(CCl4)solution is studied as a model of molecular association mixture.Analysis methods including FSMWEFA(fixed-size moving window evolving factor analysis)combined with PCA(principal component analysis),SIMPLISMA (simple-to-use interactive self-modeling mixture analysis),and ITTFA(iterative target transformation factor analysis)are adopted to resolve infrared spectra of(R)-1,3-butanediol solution.Association number and equilibrium constant are computed.(R)-1,3-butanediol in dilute inert solution is determined as a monomer-trimer equilibrium system.Theoretical investigation of trimer structures is carried out with DFT(density functional theory),and structural factors are analyzed.
文摘目的探讨纯化的隐球菌抗原肽GMFDGLSGV二聚体、四聚体、八聚体重组蛋白激发细胞毒性T淋巴细胞(Cytotoxic T lymphocyte,CTL)免疫应答的能力,为新型隐球菌疫苗的研制打下基础。方法通过细胞增殖和细胞毒性实验,研究纯化的GMFDGLSGV单体、二聚体、四聚体、八聚体重组蛋白刺激外周血单个核细胞(PBMC)产生的增殖反应和细胞毒活性,初步鉴定重组多聚体的免疫原性。结果10例HLA-A*0201阳性个体PBMC对八聚体的平均SI为37.4±3.07;增殖反应明显高于四聚体(平均SI为20.1±1.37)、二聚体(平均SI为14.1±1.06)、单体(平均SI为11.4±0.68)以及阴性对照(平均SI为1±0.10)引起的细胞增殖反应(P<0.01)。在抗原肽诱导的CTL细胞毒活性中,HLA-A*0201阳性个体PBMC对八聚体、四聚体、二聚体、单体及阴性对照组均表现不同程度的杀伤活性,平均活性分别为48.1±4.28、23.9±2.20、16.3±1.27、13.1±1.10、1.0±0.1(P<0.01)。结论本研究得到的重组优化八聚体具有较好的免疫原性,能有效刺激PBMC产生细胞增殖反应和细胞毒活性,为进一步开发有效的隐球菌疫苗打下了基础。
