Department of Biotechnology and Biosciences, University of Milano-Bicocca, 20126 Milano, Italy.
Laboratoire Architecture et Fonction des Macromolécules Biologiques (AFMB), Aix-Marseille University and CNRS, UMR 7257, 13288 Marseille, France.
Int J Mol Sci. 2020 Aug 27;21(17):6208. doi: 10.3390/ijms21176208.
The abundance of intrinsic disorder in the protein realm and its role in a variety of physiological and pathological cellular events have strengthened the interest of the scientific community in understanding the structural and dynamical properties of intrinsically disordered proteins (IDPs) and regions (IDRs). Attempts at rationalizing the general principles underlying both conformational properties and transitions of IDPs/IDRs must consider the abundance of charged residues (Asp, Glu, Lys, and Arg) that typifies these proteins, rendering them assimilable to polyampholytes or polyelectrolytes. Their conformation strongly depends on both the charge density and distribution along the sequence (i.e., charge decoration) as highlighted by recent experimental and theoretical studies that have introduced novel descriptors. Published experimental data are revisited herein in the frame of this formalism, in a new and possibly unitary perspective. The physicochemical properties most directly affected by charge density and distribution are compaction and solubility, which can be described in a relatively simplified way by tools of polymer physics. Dissecting factors controlling such properties could contribute to better understanding complex biological phenomena, such as fibrillation and phase separation. Furthermore, this knowledge is expected to have enormous practical implications for the design, synthesis, and exploitation of bio-derived materials and the control of natural biological processes.
蛋白质结构域中内源性无序的丰富性及其在各种生理和病理细胞事件中的作用,增强了科学界理解内源性无序蛋白质(IDP)和区域(IDR)的结构和动力学特性的兴趣。试图合理化 IDP/IDR 的构象特性和转变的一般原则,必须考虑到这些蛋白质的典型特征,即富含带电荷的残基(天冬氨酸、谷氨酸、赖氨酸和精氨酸),使它们可同化为多两性电解质或聚电解质。它们的构象强烈依赖于序列上的电荷密度和分布(即电荷修饰),这一点被最近的实验和理论研究所强调,这些研究引入了新的描述符。本文在该形式框架内重新审视了已发表的实验数据,从一个新的、可能统一的角度进行了研究。受电荷密度和分布影响最大的物理化学性质是紧凑性和溶解度,这些性质可以通过聚合物物理的工具以相对简化的方式来描述。剖析控制这些性质的因素有助于更好地理解复杂的生物学现象,如纤维化和相分离。此外,这方面的知识有望在生物衍生材料的设计、合成和利用以及天然生物过程的控制方面产生巨大的实际意义。