Abstract

A surprisingly small number of human genes (19–20 thousand) is not consistent with a much larger number of proteins and the number of their functions. One of the factors of functional diversity is the multifunctionality of proteins. An important subclass of such proteins is moonlighting proteins, in which one polypeptide chain performs two or more functions under different conditions. Often, these are various housekeeping proteins – glycolytic, ribosomal, and others, which are abundant in the cell. In this review we consider the structures and functions of several such proteins – the rpS3 ribosomal protein, cytochrome c, glyceraldehyde-6-phosphate dehydrogenase (GAPDH), transcription factors STAT3, β-catenin and p53. A switching of their functions occurs due to violation of the balance between their synthesis, use, and degradation, intracellular relocalization, and post-translational modifications. A significant role of the internal disordered regions in the formation of intermolecular complexes with other proteins and nucleic acids is noted. The emergence of multifunctional proteins during evolution is discussed.

中文翻译：

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多功能蛋白质

摘要

数量惊人的少量人类基因（19.2万）与大量蛋白质及其功能数目不一致。功能多样性的因素之一是蛋白质的多功能性。这类蛋白质的重要​​子类是月光蛋白质，其中一条多肽链在不同条件下具有两种或多种功能。通常，这些是多种管家蛋白-糖酵解蛋白，核糖体蛋白和其他蛋白质，它们在细胞中含量很高。在这篇综述中，我们考虑了几种此类蛋白的结构和功能-rpS3核糖体蛋白，细胞色素c，甘油醛-6-磷酸脱氢酶（GAPDH），转录因子STAT3，β-连环蛋白和p53。由于违反了它们的合成，使用和降级之间的平衡，因此会发生功能切换。细胞内重新定位和翻译后修饰。注意到内部无序区域在与其他蛋白质和核酸的分子间复合物形成中的重要作用。讨论了进化过程中多功能蛋白质的出现。