Smith Christine M
Department of Chemistry, University of Puget Sound, 1500 N. Warner, Tacoma, WA, USA.
Methods. 2005 Aug;36(4):395-403. doi: 10.1016/j.ymeth.2005.03.007.
With the emergence of the histone code as a key determinant in the regulation of gene expression, it has been important to develop tools that can not only identify the types and locations of myriad modifications, but also determine how the levels of these modifications change as a result of various processes in a cell. Mass spectrometry has become a method of choice for the investigation of post-translational modifications in histone proteins. Described in this article is a mass spectrometric method that is useful for direct quantification of levels of acetylation at lysines residues in close proximity to one another, as is the case for the amino terminal tail of histone H4. This method involves fragmentation of peptides into b and y ions that contain one or more sites of modification and isotopic labeling which ensures equivalent ionization and fragmentation.
随着组蛋白密码作为基因表达调控的关键决定因素的出现，开发不仅能够识别众多修饰的类型和位置，而且能够确定这些修饰水平如何因细胞中的各种过程而变化的工具变得至关重要。质谱已成为研究组蛋白蛋白质翻译后修饰的首选方法。本文描述了一种质谱方法，该方法可用于直接定量彼此紧邻的赖氨酸残基处的乙酰化水平，就像组蛋白H4的氨基末端尾巴那样。该方法涉及将肽片段化为包含一个或多个修饰位点的b和y离子以及同位素标记，这确保了等效的电离和碎片化。
