Díaz-Domínguez Carlos M, Eraña Hasier, Peccati Francesca, Vidal Enric, Charco Jorge M, Sampedro-Torres-Quevedo Cristina, Pérez-Castro Miguel A, Lorenzo Nuria L, Giler Samanta, Telling Glenn C, Geijo Mariví, Requena Jesús R, Jiménez-Osés Gonzalo, Castilla Joaquín
Center for Cooperative Research in Biosciences (CIC BioGUNE), Basque Research and Technology Alliance (BRTA), Derio, Spain.; Centro de Investigación Biomédica en Red de Enfermedades infecciosas (CIBERINFEC), Carlos III National Health Institute, Madrid, Spain.
Center for Cooperative Research in Biosciences (CIC BioGUNE), Basque Research and Technology Alliance (BRTA), Derio, Spain.; Centro de Investigación Biomédica en Red de Enfermedades infecciosas (CIBERINFEC), Carlos III National Health Institute, Madrid, Spain.; ATLAS Molecular Pharma S. L., Derio, Spain.
Neurobiol Dis. 2025 Sep;213:107005. doi: 10.1016/j.nbd.2025.107005. Epub 2025 Jun 13.
Protein misfolding is central to numerous neurodegenerative disorders, collectively known as proteinopathies, which include Alzheimer's disease, Parkinson's disease, and prion diseases, among others. In many cases, specific polymorphisms of the proteins associated with these diseases influence their misfolding. However, the precise ways in which these polymorphisms affect protein integrity and how they contribute to misfolding propensity remain unclear. In the case of prion diseases, they are caused by prions or PrP, the misfolded isoforms of the cellular prion protein (PrP). Chronic Wasting Disease (CWD) is a prion disease that affects cervids and can exhibit lymphotropic properties, making it the most widespread proteinopathy. For that reason, cervid PrPs and their polymorphisms have been extensively studied. To better understand the role of these polymorphisms, we analyzed 45 cervid PrP variants to assess their effects on flexibility, stability, and spontaneous misfolding propensity. The cervid variants were expressed as recombinant PrP in E. coli and were analyzed for thermal stability using circular dichroism. Additionally, the rec-PrPs served as substrates for Protein Misfolding Shaking Amplification (PMSA), enabling assessment of each variant's spontaneous misfolding propensity. This process led to the formation of bona fide prions, as confirmed by inoculation of one of the resulting conformers into transgenic mice expressing bank vole PrP. In parallel, molecular dynamics simulations were conducted to analyze the structural flexibility of the variants. While differences in protein flexibility were observed, no correlation was detected among flexibility, thermal stability, and the observed variable spontaneous misfolding propensity, suggesting that these properties are independent parameters.
蛋白质错误折叠是众多神经退行性疾病的核心问题，这些疾病统称为蛋白质病，包括阿尔茨海默病、帕金森病和朊病毒病等。在许多情况下，与这些疾病相关的蛋白质的特定多态性会影响其错误折叠。然而，这些多态性影响蛋白质完整性的确切方式以及它们如何导致错误折叠倾向仍不清楚。就朊病毒病而言，它们是由朊病毒或PrP引起的，PrP是细胞朊蛋白（PrP）的错误折叠异构体。慢性消耗病（CWD）是一种影响鹿科动物的朊病毒病，可表现出嗜淋巴特性，使其成为最广泛传播的蛋白质病。因此，鹿科动物的PrP及其多态性已得到广泛研究。为了更好地理解这些多态性的作用，我们分析了45种鹿科动物PrP变体，以评估它们对灵活性、稳定性和自发错误折叠倾向的影响。鹿科动物变体在大肠杆菌中表达为重组PrP，并使用圆二色性分析其热稳定性。此外，重组PrP作为蛋白质错误折叠振荡扩增（PMSA）的底物，能够评估每个变体的自发错误折叠倾向。通过将所得构象之一接种到表达田鼠PrP的转基因小鼠中，证实了这一过程导致了真正朊病毒的形成。同时，进行了分子动力学模拟以分析变体的结构灵活性。虽然观察到了蛋白质灵活性的差异，但在灵活性、热稳定性和观察到的可变自发错误折叠倾向之间未检测到相关性，这表明这些特性是独立的参数。
