人类胞内蛋白半衰期与其亚细胞定位的相关性研究  

Relationship between intracellular protein half-life and subcellular localization in human cells

作　　者：贾浩[1] 张小白[1] 宋晓峰[1] 

机构地区：[1]南京航空航天大学自动化学院生物医学工程系,江苏南京210016

出　　处：《计算机与应用化学》2011年第4期411-414,共4页Computers and Applied Chemistry

基　　金：江苏省自然科学基金资助项目(BK2010500)

摘　　要：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 protein plays an important role in cell cycle progression,signal transduction,and differentiation.The ubiquitin-proteasome is one of important pathways during protein selective degradation in organism which can lead the cell adapt to its new conditions proactively.The stability of protein is not only related to the sequence and structure of protein itself,but also the intracellular environment, the subcellular localization.This paper mainly researched the relationship between protein half life and its subcellular localization in cell.With abundance experiment data of proteins＇ half time and the databases of bioinformatics,an analysis and statistics are done to the compartmentation distribution of each protein.In addition,the signal peptides and several distinguishing features based on N-terminal of proteins are discussed,witch are related to the subcellular localization.The results indicated the certain relativity between the protein stability and its subcellular localization. Short-lived proteins are preferred to locate in cell membrane and membranaceous organelle and act as the secretion,signal-transducing protein and other functional proteins.The composition of N-terminal of short-lived protein sequences are majority in hydrophobic amino acid and come with signal peptides.In contrast,the long-lived proteins are inclined to locate or synthesized directly in cytoplasm and seldom provided with signal peptides,play an important role in cytoskeleton and housekeeping of cell.Furthermore,the subcellular localization can also affect the protein folding, polymerization and the process of posttranscriptional modification which have close relationship with protein stability.The research will offer not only a new pathway to think about the protein degradation but also a reference in developing prediction tools in bioinformatics research field.

关 键 词：蛋白质半衰期 亚细胞定位 胞内蛋白选择性降解 信号肽 

分 类 号：Q291[生物学—细胞生物学]