中国神经再生研究(英文版) ›› 2025, Vol. 20 ›› Issue (8): 2348-2360.doi: 10.4103/NRR.NRR-D-23-01742

• 原著:退行性病与再生 • 上一篇    下一篇

P301L-Tau 对人类 iPSC来源的皮质神经元和 Tau 转基因小鼠微管蛋白翻译后修饰的影响

  

  • 出版日期:2025-08-15 发布日期:2024-12-14

Effects of P301L-TAU on post-translational modifications of microtubules in human iPSC-derived cortical neurons and TAU transgenic mice

Mohamed Aghyad Al Kabbani1, 2, Christoph Köhler3 , Hans Zempel1, 2, *   

  1. 1 Institute of Human Genetics, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany;  2 Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany;  3 Center Anatomy, Department II, Medical Faculty, University of Cologne, Cologne, Germany
  • Online:2025-08-15 Published:2024-12-14
  • Contact: Hans Zempel, PhD, MD, hans.zempel@uk-koeln.de.
  • Supported by:
    This study was supported by the Koeln Fortune Program/Faculty of Medicine, University of Cologne, the Alzheimer Forschung Initiative e.V. (grant #22039, to HZ); open-access funding from the DFG/GRC issued to the University of Cologne; and Alzheimer Forschung Initiative e.V. for Open Access Publishing (a publication grant #P2401, to MAAK).

摘要:

Tau 是一种微管相关蛋白,可促进轴突中微管的组装和稳定性。在一系列被称为tau蛋白病的疾病中,Tau 会发生错构和聚集。微管对神经元功能至关重要,并通过一系列复杂的翻译后修饰进行调节,这些修饰的变化会影响微管的稳定性和动力学、微管与其他蛋白质/细胞结构的相互作用,并介导微管破坏酶的招募。由于微管动力学损伤会导致神经元功能障碍,实验假设人类疾病中的认知障碍也会受到微管动力学损伤的影响。因此,实验旨在研究 Tau 的致病突变(P301L)对微管稳定性和动态的微管翻译后修饰的水平和定位的影响,以评估 P301L-Tau 是否会导致微管的稳定性改变。为了研究Tau的定位、磷酸化以及对微管蛋白翻译后修饰的影响,实验在人类MAPT-KO诱导多能干细胞(iPSC)来源的神经元(iNeurons)中表达了野生型或P301L-Tau,并检测了转基因人类P301L-Tau的小鼠(pR5小鼠)海马神经元中的Tau表达。与表达内源性 Tau 的神经元相比,表达 P301L 突变的最长 Tau 异构体(2N4R)的人类神经元在 AT8(而非 p-Ser-262 表位)处的 Tau 磷酸化增加,微管的多聚谷氨酰化和乙酰化增加。P301L-Tau表现出明显的树突和轴突,其轴树突分布与外源表达的2N4R-野生型Tau相似。与非转基因小鼠相比,转基因小鼠中表达 P301L-Tau 的海马神经元表现出突出的错构化和 tau蛋白病典型的 AT8 磷酸化,微管的多聚谷氨酰化增加,但乙酰化减少。总之,P301L 突变体 Tau 导致微管 翻译后修饰发生变化,表明微管稳定性受损。这在小鼠中伴随着错构和聚集,但在人类多能干细胞衍生的神经元中却没有。微管翻译后修饰/损伤可能是tau蛋白病的关键因素。

https://orcid.org/0000-0002-7510-3077 (Hans Zempel)

Abstract: TAU is a microtubule-associated protein that promotes microtubule assembly and stability in the axon. TAU is missorted and aggregated in an array of diseases known as tauopathies. Microtubules are essential for neuronal function and regulated via a complex set of post-translational modifications, changes of which affect microtubule stability and dynamics, microtubule interaction with other proteins and cellular structures, and mediate recruitment of microtubule-severing enzymes. As impairment of microtubule dynamics causes neuronal dysfunction, we hypothesize cognitive impairment in human disease to be impacted by impairment of microtubule dynamics. We therefore aimed to study the effects of a disease-causing mutation of TAU (P301L) on the levels and localization of microtubule post-translational modifications indicative of microtubule stability and dynamics, to assess whether P301L-TAU causes stability-changing modifications to microtubules. To investigate TAU localization, phosphorylation, and effects on tubulin post-translational modifications, we expressed wild-type or P301L-TAU in human MAPT-KO induced pluripotent stem cell-derived neurons (iNeurons) and studied TAU in neurons in the hippocampus of mice transgenic for human P301L-TAU (pR5 mice). Human neurons expressing the longest TAU isoform (2N4R) with the P301L mutation showed increased TAU phosphorylation at the AT8, but not the p-Ser-262 epitope, and increased polyglutamylation and acetylation of microtubules compared with endogenous TAU-expressing neurons. P301L-TAU showed pronounced somatodendritic presence, but also successful axonal enrichment and a similar axodendritic distribution comparable to exogenously expressed 2N4R-wildtype-TAU. P301L-TAU-expressing hippocampal neurons in transgenic mice showed prominent missorting and tauopathy-typical AT8-phosphorylation of TAU and increased polyglutamylation, but reduced acetylation, of microtubules compared with non-transgenic littermates. In sum, P301L-TAU results in changes in microtubule PTMs, suggestive of impairment of microtubule stability. This is accompanied by missorting and aggregation of TAU in mice but not in iNeurons. Microtubule PTMs/impairment may be of key importance in tauopathies.

Key words: human induced pluripotent stem cell,  microtubules,  P301L,  pR5 mice,  TAU,  tauopathy,  tubulin code