Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Institute of Molecular Biology & Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6, 8010 Graz, Austria.
Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Institute of Molecular Biology & Biochemistry, Medical University of Graz, Neue Stiftingtalstrasse 6, 8010 Graz, Austria.; BioTechMed-Graz, Graz, Austria.
J Mol Biol. 2020 Apr 17;432(9):2949-2972. doi: 10.1016/j.jmb.2020.02.032. Epub 2020 Mar 2.
Proteins and their interactions control a plethora of biological functions and enable life. Protein-protein interactions can be highly dynamic, involve proteins with different degrees of "foldedness," and are often regulated through an intricate network of post-translational modifications. Central parts of protein-protein networks are intrinsically disordered proteins (IDPs). IDPs act as regulatory interaction hubs, enabled by their flexible nature. They employ various modes of binding mechanisms, from folding upon ligand binding to formation of highly dynamic "fuzzy" protein-protein complexes. Mutations or perturbations in regulation of IDPs are hallmarks of many diseases. Protein surfaces play key roles in protein-protein interactions. However, protein surfaces and protein surface accessibility are difficult to study experimentally. NMR-based solvent paramagnetic relaxation enhancement (sPRE) can provide quantitative experimental information on protein surface accessibility, which can be further used to obtain distance information for structure determination, identification of interaction surfaces, conformational changes, and identification of low-populated transient structure and long-range contacts in IDPs and dynamic protein-protein interactions. In this review, we present and discuss state-of the art sPRE techniques and their applications to investigate structure and dynamics of IDPs and protein-protein interactions. Finally, we provide an outline for potential future applications of the sPRE approach in combination with complementary techniques and modeling, to study novel paradigms, such as liquid-liquid phase separation, regulation of IDPs and protein-protein interactions by post-translational modifications, and targeting of disordered proteins.
蛋白质及其相互作用控制着大量的生物功能，使生命成为可能。蛋白质-蛋白质相互作用可能高度动态，涉及不同程度“折叠”的蛋白质，并且通常通过复杂的翻译后修饰网络进行调节。蛋白质-蛋白质网络的核心部分是固有无序蛋白质（IDP）。IDP 作为调节相互作用枢纽，其灵活的性质使其成为可能。它们采用各种结合机制模式，从配体结合时的折叠到形成高度动态的“模糊”蛋白质-蛋白质复合物。IDP 调节的突变或扰动是许多疾病的标志。蛋白质表面在蛋白质-蛋白质相互作用中起着关键作用。然而，蛋白质表面和蛋白质表面可及性很难通过实验进行研究。基于 NMR 的溶剂顺磁松弛增强（sPRE）可以提供有关蛋白质表面可及性的定量实验信息，该信息可进一步用于获得距离信息以确定结构、识别相互作用表面、构象变化以及鉴定 IDP 和动态蛋白质-蛋白质相互作用中的低丰度瞬态结构和长程接触。在这篇综述中，我们介绍并讨论了 sPRE 技术的最新进展及其在研究 IDP 和蛋白质-蛋白质相互作用结构和动力学方面的应用。最后，我们为 sPRE 方法与互补技术和建模相结合在研究新范式（如液-液相分离、翻译后修饰对 IDP 和蛋白质-蛋白质相互作用的调节以及无序蛋白质的靶向）方面的潜在未来应用提供了一个大纲。
