Copine VII在阿尔茨海默病中的作用机制研究

Copine VII (CPNE7) is a 62KD protein, but its biological function remains unclear. Preliminary RNA-seq analysis demonstrated that in the brain of animal model of Alzheimer's disease (AD) treated with nicotine exhibited enhanced expression of CPNE7 gene. qPCR and Western Blotting results showed that the expression of both CPNE7 mRNA and protein were decreased in AD models. In cells overexpressed CPNE7 apoptosis and amyloid-β protein (Aβ) production were significantly inhibited, suggesting CPNE7 may play an important role in AD pathogenesis. Phosphatidic acid/phospholipase D (PA/PLD) and nucleolin pathway are closely related to AD, and they have been shown to interact with CPNE7. We will study that (1) if and how nucleolin might mediate the effect of CPNE7 on Aβ production; and (2) the functional role of PA/PLD in CPNE7 regulation of apoptosis and autophagy in the neuronal cell line and AD animal model by experimental methods of immunoblotting, immunohistochemistry, electrophysiology and behavior analysis. This study will help to understand the mechanisms of CPNE7 in AD pathogenesis and provide experimental basis for the search of new treatment strategies.

Copine VII (CPNE7)是一个62KD的蛋白质，其功能不清。我们在对经尼古丁处理过的阿尔茨海默病(Alzheimer's disease, AD)动物模型大脑转录组测序发现CPNE7基因表达显著增加。进一步发现CPNE7 mRNA和蛋白质在AD模型中都下降。细胞过表达CPNE7抑制凋亡和β样淀粉蛋白(Aβ)相关蛋白的表达，提示CPNE7可能在AD中具有重要作用。已知磷脂酸/磷脂酶D (PA/PLD)和核仁蛋白(Nucleolin)通路与AD的发生密切相关，它们都能与CPNE7相互作用。本研究拟利用离体神经元细胞和AD动物模型，通过免疫印迹、免疫组化、电生理及动物行为学等方法，研究：(1) nucleolin介导CPNE7对Aβ通路的调节；(2) PA/PLD介导CPNE7对凋亡、自噬的影响。本项目将有助于理解CPNE7在AD中的保护作用及机制，为探讨新的治疗策略提供实验基础。

Copine VII（CPNE7）是copines家族的成员，是真核生物中进化保守的钙依赖性磷脂结合蛋白。尽管早期研究表明CPNE7几乎只在大脑中表达，但在阿尔茨海默病（Alzheimer’s disease, AD）中的功能未知。结果表明，在APP/PS1转基因小鼠海马中CPNE7表达显着降低。此外，我们发现在CPNE7过表达的HEK-APP细胞中，ADAM10，α-CTF和胰岛素降解酶（IDE）表达上调，而β位点淀粉样蛋白前体蛋白裂解酶1（BACE1）和β淀粉样蛋白（Aβ）表达下调。同时，CPNE7也抑制了磷酸化tau（p-tau，S396）和细胞周期蛋白依赖性激酶5（CDK5）的表达。最后我们发现，CPNE7抑制促炎症细胞因子（白细胞介素（IL）-1β，IL-6和Iba1）的产生。总之，CPNE7可能在AD的发病机制中发挥重要作用。