Gas-phase rearrangements do not affect site localization reliability in phosphoproteomics data sets.-猫眼课题宝

DOI：

10.1021/pr1000225

发表时间：

2010-06-04

期刊：

Journal of proteome research

影响因子：

4.4

通讯作者：

中科院分区：

生物学2区

文献类型：

作者：

Aguiar M;Haas W;Beausoleil SA;Rush J;Gygi SP

来源链接：

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2912977/?report=classic

离子阱质谱仪中碰撞诱导解离过程中磷酸根的分子内转移是近年来研究的热点。由于磷酸化事件根据MS/MS光谱中位点决定离子的存在分配给离散的丝氨酸、苏氨酸和酪氨酸残基，因此磷酸盐转移可能会使已发表的大规模磷酸化数据集中的位点定位无效或混淆。在这里，我们提出的证据，这种现象的发生使用合成磷酸肽库，特别是双电荷物种。然而，我们发现，转移反应的程度是不够的，导致本地化的磷酸化位点不正确的残基。我们进一步比较了CID的电子转移解离（ETD）的网站定位使用合成库和大规模的酵母磷酸蛋白质组实验。位点定位的一致性分别为> 99.5%和93%，表明基于ETD的位点定位不比CID更可靠。我们的结论是，分子内磷酸转移不影响当前或过去的磷酸化数据集的可靠性。

Intramolecular transfer of phosphate during collision-induced dissociation (CID) in ion trap mass spectrometers has recently been described. Because phosphorylation events are assigned to discrete serine, threonine, and tyrosine residues based on the presence of site-determining ions in MS/MS spectra, phosphate transfer may invalidate or confound site localization in published large-scale phosphorylation data sets. Here, we present evidence for the occurrence of this phenomenon using synthetic phosphopeptide libraries, specifically for doubly-charged species. We found, however, that the extent of the transfer reaction was insufficient to cause localization of phosphorylation sites to incorrect residues. We further compared CID to electron-transfer dissociation (ETD) for site localization using synthetic libraries and a large-scale yeast phosphoproteome experiment. The agreement in site localization was >99.5 and 93%, respectively, suggesting that ETD-based site localization is no more reliable than CID. We conclude that intramolecular phosphate transfer does not affect the reliability of current or past phosphorylation data sets.