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胞内蛋白的稳定性直接影响着生命活动与细胞周期。蛋白的选择性降解是通过泛素-蛋白酶体途径实现的,它是蛋白消亡的主要方式之一,同时也是细胞主动调节自身状态的体现。蛋白的稳定性除了与自身序列和结构相关外,还和成熟蛋白所处的细胞内环境,即蛋白的亚细胞定位有关。本文主要从蛋白质在细胞中的区域化分布角度研究其与蛋白寿命的关系。结合大量的蛋白半衰期实验数据以及生物信息数据库,文章统计并分析了每个蛋白的定位信息,并进一步研究了与定位有关的信号肽情况,以及应用F检验筛选出了部分能够显著区分长短寿命蛋白的N端序列特征。结果表明胞内蛋白半衰期与其亚细胞定位之间存在一定的关联性。短寿命蛋白往往定位于细胞膜或者膜性囊泡结构上,大多由信号肽引导定位,作为细胞的分泌蛋白、信号转导蛋白或者功能性蛋白发挥作用并迅速降解;而长寿命蛋白多数属于持家蛋白,定位于细胞胞浆中或直接在胞浆中合成,作为细胞骨架或者发挥着支撑细胞的作用。另外,蛋白的区域化分布影响着蛋白质的折叠、聚合以及翻译后修饰,这些过程与蛋白的稳定性有着密切的联系。本研究为将来蛋白稳定性的深入研究提供了新的思路,同时也为生物信息学中开发蛋白质稳定性相关的预测工具提供了参考。
The stability of intracellular proteins directly affects the life activities and cell cycle. Selective degradation of proteins is achieved through the ubiquitin-proteasome pathway, which is one of the major ways of protein extinction, and also a manifestation of cells actively regulating their own status. In addition to its own sequence and structure, protein stability is also related to the intracellular environment in which the mature protein is located, ie, the subcellular localization of the protein. In this paper, we mainly study the relationship between protein and protein life span from the perspective of regional distribution of proteins in cells. Combined with a large number of protein half-life experimental data and bioinformatics databases, the article statistics and analyzes each protein localization information, and further study the localization of the signal peptide situation, and the application of F-test screening out some can significantly distinguish the length of life protein N-terminal sequence characteristics. The results show that the intracellular protein half-life and its subcellular localization there is a certain correlation. Short-lived proteins are often located in the membrane or membranous vesicle structure, mostly guided by the signal peptide localization, as cell secreted proteins, signal transduction proteins or functional proteins play a role and rapidly degraded; and most of the long-lived proteins belong to the housekeeping protein , Located in the cytoplasm or directly in the cytoplasm synthesis, as a cytoskeleton or play a supporting cell role. In addition, the regionalization of proteins affects the folding, polymerization and posttranslational modification of proteins, which are closely related to the stability of proteins. This study provides a new idea for further research on protein stability in the future, and also provides a reference for the development of prediction tools related to protein stability in bioinformatics.