Posttranslational modifications of the histone 3 tail and their impact on the activity of histone lysine demethylases in vitro.
Posttranslational modifications of the histone 3 tail and their impact on the activity of histone lysine demethylases in vitro.
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DOI：
10.1371/journal.pone.0067653
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发表时间：
2013
期刊：
影响因子：
3.7
通讯作者：
Clausen RP
中科院分区：
文献类型：
--
作者：
Lohse B;Helgstrand C;Kristensen JB;Leurs U;Cloos PA;Kristensen JL;Clausen RP
组蛋白H3尾部的翻译后修饰（PTMs）如甲基化、乙酰化和磷酸化在表观遗传信号转导中起重要作用。在这里，我们研究了这些PTM中的一些在体外使用肽底物模仿组蛋白H3的甲基化赖氨酸9的去甲基化率的影响。采用与其他PTM的各种组合，通过比较酶动力学特性来研究可能的串扰效应。我们比较了仅含有催化核心（cc）的截短组蛋白赖氨酸脱甲基酶KDM 4A和KDM 4C的组蛋白尾部底物的动力学，并在全长（FL）KDM 4A和KDM 4C上表征了一些组合。我们发现，结合三甲基化K4和K9的底物导致FL-KDM 4A的催化活性显著增加。对于KDM 4A和KDM 4C的截短形式，可以观察到对双-三甲基化底物的催化活性增加两倍。此外，发现全长脱甲基酶的二甲基化和三甲基化底物之间的催化活性的显着差异与先前报道的截短脱甲基酶一致。在T11磷酸化的组蛋白肽底物不能被截短的或全长的KDM 4A和KDM 4C去甲基化，这表明苏氨酸11的磷酸化阻止了相同肽上的H3 K9 me 3标记的去甲基化。K14的乙酰化也被发现显著影响去甲基化速率。因此，对于截短的KDM 4A，底物的K14上的乙酰化导致酶催化效率（kcat/Km）的增加，而对于截短的KDM 4C，其诱导主要由Km的变化引起的降低。这项研究表明，对三甲基化H3 K9的去甲基化活性受到相同肽上其他PTM的显著影响，并强调了在肽水平上研究这些相互作用以更详细地了解表观遗传标记动态的重要性。
Posttranslational modifications (PTMs) of the histone H3 tail such as methylation, acetylation and phosphorylation play important roles in epigenetic signaling. Here we study the effect of some of these PTMs on the demethylation rates of methylated lysine 9 in vitro using peptide substrates mimicking histone H3. Various combinations with other PTMs were employed to study possible cross-talk effects by comparing enzyme kinetic characteristics. We compared the kinetics of histone tail substrates for truncated histone lysine demethylases KDM4A and KDM4C containing only the catalytic core (cc) and some combinations were characterized on full length (FL) KDM4A and KDM4C. We found that the substrates combining trimethylated K4 and K9 resulted in a significant increase in the catalytic activity for FL-KDM4A. For the truncated versions of KDM4A and KDM4C a two-fold increase in the catalytic activity toward bis-trimethylated substrates could be observed. Furthermore, a significant difference in the catalytic activity between dimethylated and trimethylated substrates was found for full length demethylases in line with what has been reported previously for truncated demethylases. Histone peptide substrates phosphorylated at T11 could not be demethylated by neither truncated nor full length KDM4A and KDM4C, suggesting that phosphorylation of threonine 11 prevents demethylation of the H3K9me3 mark on the same peptide. Acetylation of K14 was also found to influence demethylation rates significantly. Thus, for truncated KDM4A, acetylation on K14 of the substrate leads to an increase in enzymatic catalytic efficiency (k cat/K m), while for truncated KDM4C it induces a decrease, primarily caused by changes in K m. This study demonstrates that demethylation activities towards trimethylated H3K9 are significantly influenced by other PTMs on the same peptide, and emphasizes the importance of studying these interactions at the peptide level to get a more detailed understanding of the dynamics of epigenetic marks.
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影响因子：
64.5
作者：
Guenther, Matthew G.;Levine, Stuart S.;Young, Richard A.
通讯作者：
Young, Richard A.
影响因子：
2.9
作者：
Krishnan, Swathi;Collazo, Evys;Trievel, Raymond C.
通讯作者：
Trievel, Raymond C.
影响因子：
5.7
作者：
Krishnan, Swathi;Trievel, Raymond C.
通讯作者：
Trievel, Raymond C.
影响因子：
16.8
作者：
Couture, Jean-Francois;Collazo, Evys;Trievel, Raymond C.
通讯作者：
Trievel, Raymond C.
影响因子：
16
作者：
Regha K;Sloane MA;Huang R;Pauler FM;Warczok KE;Melikant B;Radolf M;Martens JH;Schotta G;Jenuwein T;Barlow DP
通讯作者：
Barlow DP