Histone methylation is central to the regulation of eukaryotic transcription. Here, we review how the histone methylation system itself is regulated. There is substantial evidence that mammalian histone methyltransferases and demethylases are phosphorylated and regulated by upstream signalling pathways. Functional studies of specific phosphosites are revealing which kinases and pathways signal to the histone methylation system and are discovering the diverse effects of phosphorylation on enzyme function. Nevertheless, the majority of phosphosites have no known kinase or function and our understanding of how histone methylation is regulated is fragmentary. Improved approaches are needed to establish and study the key regulatory phosphorylation sites on histone methyltransferases and demethylases, to avoid focus on constitutive sites which may have little regulatory purpose.

组蛋白甲基化是真核转录调控的核心。在这里，我们回顾了组蛋白甲基化系统本身是如何受到调控的。有大量证据表明哺乳动物组蛋白甲基转移酶和去甲基化酶被上游信号通路磷酸化和调节。对特定磷酸位点的功能研究揭示了哪些激酶和通路向组蛋白甲基化系统发出信号，并发现磷酸化对酶功能的多种影响。然而，大多数磷酸位点没有已知的激酶或功能，我们对组蛋白甲基化如何调节的理解是零碎的。需要改进方法来建立和研究组蛋白甲基转移酶和去甲基化酶的关键调控磷酸化位点，