Laboratory of Structural Dynamics, Stability and Folding of Proteins, Institute of Cytology, Russian Academy of Sciences, St. Petersburg, 194064, Russian Federation.
Department of Molecular Medicine, Morsani College of Medicine, USF Health Byrd Alzheimer's Research Institute, University of South Florida, 12901 Bruce B. Downs Blvd., MDC07, Tampa, FL, 33612, USA.
Protein J. 2024 Aug;43(4):675-682. doi: 10.1007/s10930-024-10207-y. Epub 2024 Jun 2.
Actin is present in the cytoplasm and nucleus of every eukaryotic cell. In the cytoplasm, framework and motor functions of actin are associated with its ability to polymerize to form F-actin. In the nucleus, globular actin plays a significant functional role. For a globular protein, actin has a uniquely large number of proteins with which it interacts. Bioinformatics analysis of the actin interactome showed that only a part of actin-binding proteins are both cytoplasmic and nuclear. There are proteins that interact only with cytoplasmic, or only with nuclear actin. The first pool includes proteins associated with the formation, regulation, and functioning of the actin cytoskeleton predominate, while nuclear actin-binding proteins are involved in the majority of key nuclear processes, from regulation of transcription to DNA damage response. Bioinformatics analysis of the structure of actin-binding proteins showed that these are mainly intrinsically disordered proteins, many of which are part of membrane-less organelles. Interestingly, although the number of intrinsically disordered actin-binding proteins in the nucleus is greater than in the cytoplasm, the drivers for the formation of the membrane-less organelles in the cytoplasm are significantly (four times) greater than in the nucleus.
肌动蛋白存在于真核细胞的细胞质和细胞核中。在细胞质中,肌动蛋白的框架和运动功能与其聚合形成 F-肌动蛋白的能力有关。在细胞核中,球状肌动蛋白发挥着重要的功能作用。作为一种球状蛋白,肌动蛋白与大量的蛋白质相互作用。肌动蛋白相互作用组的生物信息学分析表明,只有一部分肌动蛋白结合蛋白同时存在于细胞质和细胞核中。有些蛋白质仅与细胞质肌动蛋白或仅与核肌动蛋白相互作用。第一个池主要包括与肌动蛋白细胞骨架的形成、调节和功能相关的蛋白质,而核肌动蛋白结合蛋白参与大多数关键的核过程,从转录调控到 DNA 损伤反应。肌动蛋白结合蛋白结构的生物信息学分析表明,这些蛋白主要是内在无序蛋白,其中许多是无膜细胞器的一部分。有趣的是,尽管核内无序肌动蛋白结合蛋白的数量多于细胞质,但细胞质中形成无膜细胞器的驱动力比核内大得多(四倍)。