同位素稀释法在绝对定量蛋白质组中的研究进展

绝对定量蛋白质组是指基于蛋白质组学方法对细胞、组织或体液中的蛋白质进行绝对量或浓度测定．目前，常用的绝对定量方法主要有基于同位素稀释法的蛋白质组学绝对定量方法和基于质谱数据统计分析的非标记方法．基于同位素稀释法的绝对定量方法是用已知量的同位素标记物对与其混合的样本蛋白质浓度进行测定．常见的同位素标记物包括：由AQUA法、QconCAT法产生的特异性水解肽段，由PSAQ法、Absolute SILAC法产生的标记蛋白和由PrESTs-SILAC法产生的蛋白抗原表位标签．由于同位素稀释法可以对蛋白质进行准确和精确定量，对于临床疾病的诊断和治疗具有明显的现实意义．本文对同位素稀释法在绝对定量蛋白质组中的研究进展及其优缺点和最新应用进行了评述．

Development of Absolute Quantification of Proteome Based on Isotope Dilution

Absolute quantification methodologies, which allow the determination of protein concentrations in biological samples such as cell, tissue and body fluid. Recently, protein quantification methodologies mainly are one which rely on the isotope dilution for absolute quantification of proteome and another one which rely on the statistic analysis of MS data called the lable-free technique. In these approaches, the sample is spiked with defined amounts of isotope-labeled analogue(s) of specific proteolytic peptide(s) (AQUA and QconCAT strategies) or protein(s) (PSAQ strategy) or PrESTs (PrESTs-SILAC). Because isotope dilution can provide accurate and presice absolute quantification, so they are crucial for specific applications such as the evaluation of clinical biomarker candidates and understanding the biological function of proteins. In this review, we present a critical overview of these isotope dilution methodologies.