Detailed map of oxidative post-translational modifications of human p21ras using Fourier transform mass spectrometry.
Detailed map of oxidative post-translational modifications of human p21ras using Fourier transform mass spectrometry.
复制标题
使用傅里叶变换质谱法绘制的人 p21ras 氧化翻译后修饰的详细图谱。
DOI：
10.1021/ac060525v
复制
发表时间：
2006
影响因子：
7.4
通讯作者：
O'Connor,PeterB
中科院分区：
文献类型：
--
作者：
Zhao,Cheng;Sethuraman,Mahadevan;Clavreul,Nicolas;Kaur,Parminder;Cohen,RichardA;O'Connor,PeterB
P21ras, the translation product of the most commonly mutated oncogene, is a small guanine nucleotide exchange protein. Oxidant-induced post-translational modifications of p21ras including S-nitrosation and S-glutathiolation have been demonstrated to modulate its activity. Structural characterization of this protein is critical to further understanding of the biological functions of p21ras. In this study, high-resolution and high mass accuracy Fourier transform mass spectrometry was utilized to map, in detail, the post-translational modifications of p21ras (H-ras) exposed to oxidants by combining bottom-up and top-down techniques. For peroxynitrite-treated p21ras, five oxidized methionines, five nitrated tyrosines, and at least two oxidized cysteines (including C118) were identified by “bottom-up” analysis, and the major oxidative modification of C118, Cys118−SO3H, was confirmed by several tandem mass spectrometry experiments. Additionally, “top-down” analysis was conducted on p21ras S-glutathiolated by oxidized glutathione and identified C118 as the major site of glutathiolation among the four surface cysteines. The present study provides a paradigm for an effective and efficient method not only for mapping post-translational modifications of proteins but also for predicting the relative selectivity and specificity of oxidative post-translational modifications, especially using top-down analysis.
