2011 Collaborative Innovation Center of Tianjin for Medical Epigenetics, Tianjin Key Laboratory of Medical Epigenetics, Key Laboratory of Breast Cancer Prevention and Therapy (Ministry of Education), Cancer Institute and Hospital , Tianjin Medical University , Tianjin 300070 , China.
Anal Chem. 2018 Mar 20;90(6):3692-3696. doi: 10.1021/acs.analchem.7b05174. Epub 2018 Feb 28.
Combinatorial histone post-translational modifications (HPTMs) form a complex epigenetic code that can be decoded by specific binding proteins, termed as readers. Their specific interplays have been thought to determine gene expression and downstream biological functions. However, it is still a big challenge to analyze such interactions due to various limitations including rather weak, transient, and complicated interactions between HPTMs and readers, the high dynamic property of HPTMs, and the low abundance of reader proteins. Here we sought to take advantage of DNA-templated and photo-cross-linking techniques to design a group of combinatorial histone PTM peptide probes for the identification of multivalent interactions among histone PTMs and readers. By use of trimethylation on histone H3K4 (H3K4me3) and phosphorylation on H3T3, we demonstrated that this approach can be successfully utilized for identification of the PTM crosstalk on the same histone. By use of H3K4me3 and acetylation on H4K16, we showed the potential application of the probe in the multivalent interactions among PTMs on different histones. Thus, this new chemical proteomics tool combined with mass spectrometry holds a promising potential in profiling of the readers of combinatorial HPTMs and characterization of crosstalk among multiple PTMs on histones and can be adapted for broad biomedical applications.
组合组蛋白翻译后修饰 (HPTMs) 形成了一种复杂的表观遗传密码，可以被特定的结合蛋白（称为读取器）解码。它们的特定相互作用被认为决定了基因表达和下游的生物学功能。然而，由于各种限制，分析这些相互作用仍然是一个巨大的挑战，包括 HPTMs 和读取器之间的相互作用较弱、瞬时和复杂、HPTMs 的高动态特性以及读取器蛋白的低丰度。在这里，我们试图利用 DNA 模板和光交联技术设计一组组合组蛋白 PTM 肽探针，用于鉴定组蛋白 PTM 和读取器之间的多价相互作用。通过使用组蛋白 H3K4 上的三甲基化（H3K4me3）和 H3T3 上的磷酸化，我们证明了这种方法可以成功地用于鉴定同一组蛋白上的 PTM 串扰。通过使用 H3K4me3 和 H4K16 上的乙酰化，我们展示了该探针在不同组蛋白上的 PTM 之间的多价相互作用中的潜在应用。因此，这种新的化学蛋白质组学工具与质谱相结合，在组合 HPTMs 的读取器分析和组蛋白上多个 PTM 之间的串扰特征方面具有广阔的应用前景。
