中国神经再生研究(英文版)

• 观点:神经损伤修复保护与再生 • 上一篇    下一篇

蛋白质二硫键异构酶ERp57在神经退行性变及轴突再生中的作用

  

  • 收稿日期:2016-02-03 出版日期:2016-02-15 发布日期:2016-02-15

ERp57 in neurodegeneration and regeneration

Leslie Bargsted, Claudio Hetz, Soledad Matus   

  1. Neurounion Biomedical Foundation, CENPAR, Santiago, Chile;Biomedical Neuroscience Institute, Faculty of Medicine, University of Chile, Santiago, Chile; Center for Geroscience, Brain Health and Metabolism, Santiago, Chile (Bargsted L, Hetz C, Matus S)Institute of Biomedical Sciences, Center for Molecular Studies of the Cell, Program of Cellular and Molecular Biology, University of Chile, Santiago, Chile; Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA, USA (Hetz C)
  • Received:2016-02-03 Online:2016-02-15 Published:2016-02-15
  • Contact: Soledad Matus, Ph.D. or Claudio Hetz, Ph.D.,soledad.matus@neurounion.com or clahetz@med.uchile.cl,chetz@hsph.harvard.edu.

摘要:

蛋白质二硫键异构酶及其类蛋白, 是硫氧还蛋白超家族的一员, 具有催化蛋白质二硫键氧化、还原和异构的功能, 并具有分子伴侣和抗分子伴侣活性及钙离子结合位点, 在生物体内起着极其重要的作用。蛋白质二硫键异构酶ERp57与神经变性疾病密切相关。为了确定ERp57对体内神经变性的影响,Claudio Hetz教授构建了中枢神经系统过表达ERp57的转基因小鼠,并用神经毒素 6-羟基多巴胺来触发转基因小鼠的多巴胺能神经元发生变性。正如作者最初的预测,过表达ERp57状态下,未见多巴胺能神经元的丢失,同样,纹状体的神经支配或运动功能也没有变化。有趣的是,在周围神经损伤的情况下,ERp57可显著促进轴突再生。ERp57 转基因小鼠表现出显著的促神经损伤后运动功能恢复。 这些结果第一次描述细胞内蛋白质稳态平衡在轴突再生的功能作用。我们推测缺乏保护 PD 模型中可能是由于对 6-羟基多巴胺引起的氧化还原不平衡造成的异位 ERp57 氧化失活所导致。

Abstract:

The protein disulfide isomerases (PDIs) family has a central function in the folding of proteins synthetized through the secretory pathway. ERp57, also known as Grp58 or PDIA3, is one of the main studied members of this family. ERp57 catalyzes the formation, disruption and isomerization of disulfide bonds of glycoproteins mediated by a cooperative interaction with the endoplasmic reticulum (ER) chaperones calnexin and calreticulin. In the past years, several studies have linked ERp57 and its closest homologue PDI (also known as PDIA1) to diseases affecting the central nervous system, including amyotrophic lateral sclerosis, Parkinson’s disease, Alzheimer’s disease, among others. These neurodegenerative conditions are characterized by the presence of abnormal protein aggregates containing specific proteins, which are now classified as protein misfolding disorders (PMDs). The available evidence is depicting a novel scenario,
placing PDIs as interesting targets for disease intervention. Due to the fact synaptic dysfunction are salient features of most neurodegenerative conditions, the possible consequences of enforcing ERp57 expression in the brain (i.e., using gene therapy) should be explored as a strategy to improve neuronal survival, synaptic function, and enhance tissue regeneration where ERp57 could act over protein substrates involved in synaptic functions. It remains to be elucidated if other functions beyond the ER can be attributed to the beneficial effects of ERp57 expression. Of note, ERp57 has been described in subcelular localizations beyond the ER, including the nucleus, the plasma membrane and cytoplasm (Turano et al., 2002). The new mouse models generated to manipulate ERp57 levels in the nervous system represent relevant tools to assess the function of this foldase to diverse diseases. Since the PDI family of proteins
involves more than 20 members, we predict that this field will accelerate and develop toward the identification of novel functions of PDIs and other components of the ER proteostasis network on a variety of pathologies involving altered function of the secretory pathway.