澳大利亚乐卓博大学Yuning Hong研究组完成了细胞内内源性蛋白质无序区域的全局分析。相关论文于2024年11月25日在线发表在《自然—方法学》杂志上。

研究人员提出了一种方法，使用一种双功能化学探针，命名为TME，来原位捕捉、富集并定量细胞中的内源性蛋白质无序性。TME在与表面暴露的自由半胱氨酸及灵活环境中的蛋白质选择性结合时，表现出荧光开启效应，这是蛋白质无序的特征性标志。

通过基于亲和力的蛋白质组学方法，研究人员识别了基础无序蛋白以及那些在压力下折叠状态发生变化的蛋白，且能够覆盖低丰度的蛋白质。在来自帕金森病患者和健康对照的淋巴母细胞系中，研究人员的TME策略比裂解液谱分析方法更有效地区分了这两组。

高通量TME荧光和蛋白质组学进一步揭示了一种普遍的细胞质量控制机制，即细胞通过采用易聚集的分布并隔离无序蛋白质来适应蛋白质稳态压力，正如亨廷顿病细胞模型中所示。

研究人员表示，蛋白质结构中的无序性和灵活性对于生物功能至关重要，但也可能促成疾病的发生，如神经退行性疾病。然而，在生物学基质中以蛋白质组规模表征蛋白质折叠仍然具有挑战性。

附：英文原文

Title: Global analysis of endogenous protein disorder in cells

Author: Zhang, Shouxiang, Owyong, Tze Cin, Sanislav, Oana, Englmaier, Lukas, Sui, Xiaojing, Wang, Geqing, Greening, David W., Williamson, Nicholas A., Villunger, Andreas, White, Jonathan M., Heras, Begoa, Wong, Wallace W. H., Fisher, Paul R., Hong, Yuning

Issue&Volume: 2024-11-25

Abstract: Disorder and flexibility in protein structures are essential for biological function but can also contribute to diseases, such as neurodegenerative disorders. However, characterizing protein folding on a proteome-wide scale within biological matrices remains challenging. Here we present a method using a bifunctional chemical probe, named TME, to capture in situ, enrich and quantify endogenous protein disorder in cells. TME exhibits a fluorescence turn-on effect upon selective conjugation with proteins with free cysteines in surface-exposed and flexible environments—a distinctive signature of protein disorder. Using an affinity-based proteomic approach, we identify both basal disordered proteins and those whose folding status changes under stress, with coverage to proteins even of low abundance. In lymphoblastoid cells from individuals with Parkinson’s disease and healthy controls, our TME-based strategy distinguishes the two groups more effectively than lysate profiling methods. High-throughput TME fluorescence and proteomics further reveal a universal cellular quality-control mechanism in which cells adapt to proteostatic stress by adopting aggregation-prone distributions and sequestering disordered proteins, as illustrated in Huntington’s disease cell models.

DOI: 10.1038/s41592-024-02507-z

Source: https://www.nature.com/articles/s41592-024-02507-z