质谱技术鉴定细胞中组蛋白翻译后修饰的研究进展

组蛋白是真核细胞中构成染色质内核小体的主要元件,其翻译后修饰蕴藏着组蛋白密码,是表观遗传学的重要内容,影响染色质的结构和功能,进而调控基因表达。组蛋白翻译后修饰形式的鉴定是揭示组蛋白密码的关键,目前质谱技术已经成为分析组蛋白及其翻译后修饰的重要工具。本文综述了组蛋白翻译后修饰鉴定方法的新进展,介绍了基于质谱技术"bottom-up"和"top-down"的组蛋白分析策略,及CID、ECD和ETD等鉴定组蛋白修饰位点的质谱碎片裂解技术,并结合当前研究进展,评述了质谱技术在组蛋白翻译后修饰谱的鉴定、组蛋白各种变体的测定,以及在生理过程中组蛋白修饰丰度动态变化的定量分析等方面应用的新进展。

Development of Identification for Post-Translational Modifications in Histones by Mass Spectrometry Based Proteomics

In eukaryotic cells, chromosomal DNA is packaged into a compact structure, chromatin, with the help of four core histones. The fundamental repeating unit of chromatin is the nucleosome, which contains an octamer of core histones, around 147 base pairs of DNA are wrapped. Post-translational modifications (PTMs) in histones are generally considered to be a major group of epigenetic marks. Accordingly because PTMs alter the properties of histones, hence, affect histone structure and function and regulate the gene expression. Therefore, identification of histones PTMs is the key to discover histone codes. At present mass spectrometry has become a powerful analysis tool. Here, we introduced the novel development of the strategies based on mass spectrometry ("bottom up" and "top down") in mapping histone PTMs, fragment dissociation technologies such as CID, ECD and ETD. We also reported the application of mass spectrometry in addressing histone PTMs sites, identifying histone variants and quantifying differential expression of these PTMs in cells. Contents
1 The strategies and methods of identification for post-translational modifications in histones by mass spectrometry
1.1 The strategy for histone analysis based mass spectrometry
1.2 MS fragmentation
2 The application of mass spectrometry in post-translational modifications in histones
2.1 Identification and characterization of post-translation modifications in histones
2.2 Identification and characterization of histone variants
2.3 Quantification based mass spectrometry for post-translational modifications in histones