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类型 基础研究 预答辩日期 2017-12-29
开始(开题)日期 2015-01-19 论文结束日期 2017-10-31
地点 李文正楼北225 论文选题来源 国家自然科学基金项目     论文字数 5.1 (万字)
题目 果蝇Neuroligin3的剪切机制与功能研究
主题词 果蝇,Neuroligin3,蛋白剪切,TACE蛋白酶,运动能力
摘要 神经细胞粘附分子Neuroligins (Nlgs)是定位于突触后的跨膜蛋白,它们在突触以及功能中发挥重要的作用。Nlgs的突变和孤独症等认知疾病的发生存在很大的关联性。Nlgs分子功能往往受到蛋白翻译后的加工修饰,例如:蛋白酶ADAM10/MMP9介导哺乳动物Nlg1的剪切以调节神经活性;果蝇DNlg2(Drosophila Nlg2)分子在胞内被剪切后才能转运至细胞膜上成为成熟形式。本实验室之前报道内源性的DNlg3在果蝇头部呈现多条特异性条带,暗示DNlg3可能经历被蛋白酶加工的过程。但其分子机制及其功能仍不清楚。 因此,本研究运用一系列实验方法包括生物化学,分子生物学,遗传学和行为学分析等手段揭示一套剪切机制:DNlg3在神经系统成熟并行使功能依赖于剪切加工事件。我们发现DNlg3只在神经系统中被特异性剪切,。同时,我们鉴定到TACE蛋白酶介导DNlg3在其胞外的乙酰胆碱样结构域(A520–N532)发生剪切。剪切产生N端片段(NTF)和依然锚定在膜上的short DNlg3 (sDNlg3)。DNlg3被持续性剪切而不依赖于神经活性。有意思的是,DNlg3在转运至细胞膜之前,就在高尔基体中被剪切,这种剪切方式区别于大多数膜蛋白包括小鼠Nlg1在细胞膜上才被剪切的方式。行为学分析结合遗传学方法的研究表明DNlg3剪切对果蝇运动能力的正常维持至关重要。因此,本研究揭示一种DNlg3被剪切的新机制机制以及神经系统DNlg3的成熟对维持果蝇运动能力的重要性。同时,本研究可能给不同物种Nlgs在神经系统中成熟的机制提供一种新视角。
英文题目 Mechanism and function of Drosophila Neuroligin3 proteolytic cleavage
英文主题词 Drosophila, Neuroligin3, proteolytic cleavage, TACE, locomotion
英文摘要 Neuroligins (Nlgs) are postsynaptic adhesion molecules that are essential for synaptic and development function. Mutations in Nlgs have been implicated in cognitive diseases such as autism.The functions of autism-associated Nlgs are modulated by their post-translational modifications, such as proteolytic cleavage of rodent Nlg1 by matrix metalloproteinase (MMP)-9/a disintegrin and metalloproteinase (ADAM)-10 to regulate neuronal activity and of Drosophila Nlg2 (DNlg2), the latter of which is needed for its trafficking and maturation. A previous study has shown that there are different endogenous forms of DNlg3 in Drosophila heads, indicating it may undergo proteolytic processing. However, the molecular mechanism and function underlying DNlg3 proteolytic processing is unknown. In our present study, using a broad range of experimental methods including cell culture, immunohistochemistry, western blotting, genetic studies and behavior analysis to reveal a novel proteolytic mechanism that is essential for DNlg3 maturation and function in the central nervous system. We idendify that tumor necrosis factor α-converting enzyme (TACE) cleaves DNlg3 exclusively at its extracellular acetylcholinesterase-like domain (A520–N532) to generate the N-terminal fragment (NTF) and the short membrane-anchored fragment (sDNlg3) . DNlg3 is constitutively processed in an activity-independent manner. Interestingly, DNlg3 is cleaved intracellularly in the Golgi apparatus before it arrived at the cell surface, a unique cleavage mechanism that is distinct from ‘conventional’ ectodomain shedding of membrane proteins, including rodent Nlg1. Genetic studies show that sDNlg3 is essential for maintaining proper locomotor activity in Drosophila. In summary, our results reveal a unique cleavage mechanism of DNlg3 and a neuron-specific role for DNlg3 maturation in the regulation of locomotor activity. Our study may provide a new insight into a cleavage mechanism of Nlgs maturation in nervous system.
学术讨论
主办单位时间地点报告人报告主题
东南大学 2016-09-02 李文正楼北225 钱进军 Functional studies on one intronic miR-932 hosted in Drosophila Neuroligin2
东南大学 2016-12-12 李文正楼北225 屠仁军 Mechanism and function of Drosophila Neuroligin 2 proteolytic cleavage
东南大学 2017-01-16 李文正楼北225 吴俊 TACE Regulates Drosophila sleep
东南大学 2017-03-29 李文正楼北225 吴俊 Proteolytic cleavage of Drosophila Neuroligin3 is essential for maintaining locomotor activity
东南大学 2017-04-17 李文正楼南213 Wang hongyu New animal models for studying regulation of lipid metabolism
东南大学 2017-05-31 李文正楼北225 吴俊 Proteolytic cleavage of Drosophila Neuroligin3 in CNS
东南大学 2017-06-12 李文正楼北225 芮梦龙 Neurexin Interacts with Dystroglycan and Laminin C to Sustain Normal Muscle Architecture and Function in Drosophila
东南大学 2017-06-26 李文正楼北225 吴俊 Proteolytic Maturation of Drosophila Neuroligin 3 by TCAE in CNS
     
学术会议
会议名称时间地点本人报告本人报告题目
4th International Conference on Integrative Biology 2016/07/18-20 德国 柏林 Proteolytic Maturation of Drosophila Neuroligin3 in The Central Nervous System
2013江苏省遗传学会年会 2013/11/23-24 江苏省徐州市 Drosophila Neuroligin3 Underdoes Proteolytic Cleavage in The Central Nervous System
     
代表作
论文名称
Proteolytic Maturation of Drosophila Neuroligin 3 by Tumor Necrosis Factor α-converting Enzyme in th
 
答辩委员会组成信息
姓名职称导师类别工作单位是否主席备注
石云 正高 教授 博导 南京大学
徐晓军 正高 教授 博导 中国药科大学
韩俊海 正高 教授 博导 东南大学
潘玉峰 正高 教授 博导 东南大学
罗卓娟 正高 教授 博导 东南大学
      
答辩秘书信息
姓名职称工作单位备注
黄洁 其他 讲师 东南大学