A Neuronal Culture System to Detect Prion Synaptotoxicity.
A Neuronal Culture System to Detect Prion Synaptotoxicity.
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DOI：
10.1371/journal.ppat.1005623
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发表时间：
2016-05
期刊：
影响因子：
6.7
通讯作者：
Harris DA
中科院分区：
文献类型：
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作者：
Fang C;Imberdis T;Garza MC;Wille H;Harris DA
突触病理是朊病毒和其他神经退行性疾病的早期特征。虽然朊病毒传播的自我模板化过程已经很好地建立，但朊病毒引起突触毒性的机制仍然知之甚少，这主要是由于缺乏实验上易于处理的细胞培养模型。在这里，我们报告说，暴露培养的海马神经元PrPSc，朊病毒蛋白的感染性亚型，结果在树突棘的快速收缩。这种作用完全依赖于靶神经元表达的细胞朊病毒蛋白PrPC，以及PrPC分子N-末端存在的9个氨基酸的多碱基区域。蛋白酶抗性和蛋白酶敏感形式的PrPSc引起树突损失。该系统为朊病毒神经毒性机制提供了新的见解，并为表征PrPSc的不同致病形式和测试潜在的治疗剂提供了平台。朊病毒疾病是致命的神经退行性疾病，可导致记忆丧失、协调能力受损和运动异常。朊病毒疾病的分子罪魁祸首是PrPSc，它是宿主编码的糖蛋白（PrPC）的一种感染性同种型，可以通过自我模板机制自我繁殖。PrPSc本身是否对神经元有毒，如果是的话，它产生神经元病理的细胞机制在很大程度上是未知的，部分原因是缺乏合适的细胞培养模型。在这里，我们描述了一个海马神经元文化系统，以检测的毒性作用的PrPSc树突棘，这是突触后元件负责兴奋性突触传递，这是有牵连的学习，记忆，和神经退行性疾病的最早阶段。我们发现，纯化的，外源性应用的PrPSc引起急性收缩的树突棘，效果是完全依赖于表达的PrPC的靶神经元，并在上的存在下的9个氨基酸，在N-末端的PrPC分子的多元区域。蛋白酶抗性和蛋白酶敏感形式的PrPSc引起树突状回缩。该系统为朊病毒神经毒性机制提供了新的见解，并为表征不同致病形式的PrPSc和测试潜在的治疗药物提供了平台。
Synaptic pathology is an early feature of prion as well as other neurodegenerative diseases. Although the self-templating process by which prions propagate is well established, the mechanisms by which prions cause synaptotoxicity are poorly understood, due largely to the absence of experimentally tractable cell culture models. Here, we report that exposure of cultured hippocampal neurons to PrPSc, the infectious isoform of the prion protein, results in rapid retraction of dendritic spines. This effect is entirely dependent on expression of the cellular prion protein, PrPC, by target neurons, and on the presence of a nine-amino acid, polybasic region at the N-terminus of the PrPC molecule. Both protease-resistant and protease-sensitive forms of PrPSc cause dendritic loss. This system provides new insights into the mechanisms responsible for prion neurotoxicity, and it provides a platform for characterizing different pathogenic forms of PrPSc and testing potential therapeutic agents. Prion diseases are fatal neurodegenerative disorders that cause memory loss, impaired coordination, and abnormal movements. The molecular culprit in prion diseases is PrPSc, an infectious isoform of a host-encoded glycoprotein (PrPC) that can propagate itself by a self-templating mechanism. Whether PrPSc itself is toxic to neurons, and if so, the cellular mechanisms by which it produces neuronal pathology are largely unknown, in part because of the absence of suitable cell culture models. We describe here a hippocampal neuronal cultural system to detect the toxic effect of PrPSc on dendritic spines, which are postsynaptic elements responsible for excitatory synaptic transmission, and which are implicated in learning, memory, and the earliest stages of neurodegenerative diseases. We found that purified, exogenously applied PrPSc causes acute retraction of dendritic spines, an effect that is entirely dependent on expression of PrPC by target neurons, and on the on the presence of a nine-amino acid, polybasic region at the N-terminus of the PrPC molecule. Both protease-resistant and protease-sensitive forms of PrPSc cause dendritic retraction. This system provides new insights into the mechanisms responsible for prion neurotoxicity, and it provides a platform for characterizing different pathogenic forms of PrPSc and testing potential therapeutic agents.