Study on the Changes and Functions of Prohibitin During the Apoptosis of the Human Osteosarcoma MG-63 Cells

本论文以姜黄素诱导人成骨肉瘤MG-63细胞凋亡，运用亚细胞蛋白质组学技术对MG-63细胞凋亡前后核基质蛋白的组成变化进行系统分析，发现细胞凋亡过程中的特异核基质蛋白Prohibitin表达下调。生物信息学初步分析显示差异表达蛋白参与了细胞死亡和存活以及细胞周期等调控过程，涉及G2/M期DNA损伤检验点调控、Myc介导的细胞凋亡等信号通路，而Prohibitin是其中的关键调控蛋白。在此基础上，对Prohibitin在MG-63细胞诱导凋亡前后的表达和定位变化，及其与相关癌基因、抑癌基因产物的共定位及相互作用关系进行了研究。蛋白质免疫印迹杂交证实在人成骨肉瘤MG-63细胞诱导凋亡后，Prohib...In this study, curcumin was used to induce apoptosis of the human osteosarcoma MG-63 cells. By using subcellular proteomics technology, we performed a systematic analysis on expression changes of the nuclear matrix proteins in MG-63 cells before and after apoptosis, and found that Prohibitin was down-regulated during apoptosis. Bioinformatics analysis of differentially expressed proteins showed th...学位：理学硕士院系专业：生命科学学院_细胞生物学学号：2162010115242

Expression and localization changes of nucleophosmin during apoptosis of human esophageal cancer EC9706 cells induced by curcumin

目的探讨核磷蛋白nPM在癌细胞诱导凋亡过程中在细胞内、细胞核基质上的定位与表达变化,以及nPM与凋亡调控相关蛋白的关系,探索其在凋亡调控中的作用。方法在姜黄素诱导人食管癌EC9706细胞凋亡的基础上,以亚细胞蛋白质组学方法分析nPM在核基质中的存在与变化,并以免疫印迹法杂交实验进行确证;激光扫描共焦显微镜观察nPM在EC9706细胞凋亡过程中的定位与变化,以及nPM与bAX、bCl-2等基因产物的共定位关系。结果 nPM存在于EC9706细胞核基质蛋白组分中,并在姜黄素处理后表达下调。nPM在EC9706细胞凋亡过程中发生显著的胞质-核之间的穿梭定位变化,并与bAX、bCl-2等蛋白具有共定位关系,且共定位区域发生了变化。结论 nPM是一种核基质结合蛋白,在EC9706细胞凋亡中的表达与定位变化,及其与凋亡调控蛋白的共定位关系提示,它在EC9706细胞凋亡调控中具有重要作用。Objective To explore the expression and localization change of nucleophosmin( NPM) in the nuclear matrix of cancer cells and its relationships with apoptosis regulating proteins during induced apoptosis,and to discuss its regulating functions in apoptosis.Methods Curcumin was used to induce apoptosis of human esophageal cancer EC9706 cells.By using subcellular proteomics technology we analyzed the presence and expression change of NPM in the nuclear matrix.We performed a Western blotting analysis to confirm the change.Subsequently,we examined the localization change of NPM and its co-localization with apoptotic gene products such as Bax and Bcl-2 through laser scanning confocal microscopy.Results The results of this study showed that NPM existed in the nuclear matrix of EC9706 cells with a remarkable down-regulation after curcumin treatment.We demonstrated that NPM exhibited a distinct nucleocytoplasmic shuttling during induced apoptosis.NPM was co-localized with Bax,Bcl-2 and their co-localization regions changed during the process of apoptosis.Conclusion NPM is a nuclear matrix associated protein.Its altered expression and localization, as well as its co-localization with apoptosis regulating proteins suggest the important regulative functions in apoptosis of EC9706 cells.国家自然科学基金资助项目(81071669;81272921;81272245

Regulatory mechanism of prohibitin in human osteosarcoma MG-63 cells during apoptosis induced by curcumin

目的探讨姜黄素(CurCuMIn)诱导成骨肉瘤细胞凋亡前后,PrOHIbITIn(PHb)蛋白的定位与表达变化,及PHb与凋亡相关基因产物的共定位关系。方法选择性抽提经姜黄素诱导处理前后的人成骨肉瘤Mg-63细胞核基质蛋白,以蛋白质组学、免疫印迹法和激光扫描共焦显微技术对PHb在核基质中存在、分布及其与凋亡相关基因产物在Mg-63细胞中的共定位关系进行了研究。结果双向凝胶电泳、质谱鉴定和免疫印迹法结果显示,PHb存在于Mg-63细胞核基质蛋白组分中,细胞凋亡后在细胞核基质蛋白中表达下调。免疫荧光显微镜观察显示,PHb定位于Mg-63细胞核基质纤维上,经姜黄素处理后出现分布位置与表达水平的变化。激光扫描共焦显微镜观察结果显示,PHb在Mg-63细胞凋亡过程中与bAX、bCl-2、fAS、P53、C-MyC和rb等基因产物具有共定位关系,且共定位区域发生了变化。结论 PHb是一种核基质结合蛋白;PHb在Mg-63细胞凋亡过程中的表达与分布变化,及其与细胞凋亡相关基因的共定位关系,对Mg-63细胞凋亡具有重要影响。Objective To investigate the expression and distribution of prohibitin in cellular nuclear matrix and the co-localization between prohibitin and the products of apoptosis-related genes in human osteosarcoma MG-63 cell before and after curcumin treatment.Methods Nuclear matrix proteins were selectively extracted and subjected to twodimensional gel electrophoresis analysis,immunoblotting,and microscopy.Results Two-dimensional polyacrylamide Gel electrophoresis and mass spectrum analysis showed that prohibitin existed in the nuclear matrix protein components of the MG-63 cell and its expression were down-regulated by curcumin.The change of prohibitin was further confirmed by immunoblotting.The immunofluorescence microscopy observation demonstrated that the prohibitin located in the filaments of the nuclear matrix of MG-63 cell and its distribution and expression were altered after curcumin treatment.Laser scanning confocal microscopy revealed that there were co-localization between prohibitin and the products of Bax,Bcl-2,Fas,P53,c-Myc,and Rb genes in MG-63 cell,and the site of co-localization was altered by curcumin treatment.Couclusion Current research identifiys that prohibitin is a nuclear matrix protein existing in the nuclear matrix.The alteration of expression and distribution of prohibitin,and the relationship between prohibitin and multiple apoptosis-related genes mayplay a pivotal role in the process of human osteosarcoma MG-63 cell apoptosis.These results contribute to the elucidation of the regulatory mechanisms of tumor cellular apoptosis.国家自然科学基金资助项目(81071669;81272921;81272245;81201305); 福建省自然科学基金资助项目(2011J01256;2013J01359

Prediction of Energy Resolution in the JUNO Experiment

International audienceThis paper presents the energy resolution study in the JUNO experiment, incorporating the latest knowledge acquired during the detector construction phase. The determination of neutrino mass ordering in JUNO requires an exceptional energy resolution better than 3% at 1 MeV. To achieve this ambitious goal, significant efforts have been undertaken in the design and production of the key components of the JUNO detector. Various factors affecting the detection of inverse beta decay signals have an impact on the energy resolution, extending beyond the statistical fluctuations of the detected number of photons, such as the properties of liquid scintillator, performance of photomultiplier tubes, and the energy reconstruction algorithm. To account for these effects, a full JUNO simulation and reconstruction approach is employed. This enables the modeling of all relevant effects and the evaluation of associated inputs to accurately estimate the energy resolution. The study reveals an energy resolution of 2.95% at 1 MeV. Furthermore, the study assesses the contribution of major effects to the overall energy resolution budget. This analysis serves as a reference for interpreting future measurements of energy resolution during JUNO data taking. Moreover, it provides a guideline in comprehending the energy resolution characteristics of liquid scintillator-based detectors

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies