Graduate Institute of Cancer Biology and Center for Molecular Medicine, China Medical University, Taichung 404, Taiwan; Department of Biotechnology, Asia University, Taichung 413, Taiwan.
Graduate Institute of Cancer Biology and Center for Molecular Medicine, China Medical University, Taichung 404, Taiwan; Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
Dev Cell. 2014 Jul 28;30(2):224-37. doi: 10.1016/j.devcel.2014.06.008.
Posttranslational modifications of histones play fundamental roles in many biological functions. Specifically, histone H4-K20 methylation is critical for DNA synthesis and repair. However, little is known about how these functions are regulated by the upstream stimuli. Here, we identify a tyrosine phosphorylation site at Y72 of histone H4, which facilitates recruitment of histone methyltransferases (HMTases), SET8 and SUV4-20H, to enhance its K20 methylation, thereby promoting DNA synthesis and repair. Phosphorylation-defective histone H4 mutant is deficient in K20 methylation, leading to reduced DNA synthesis, delayed cell cycle progression, and decreased DNA repair ability. Disrupting the interaction between epidermal growth factor receptor (EGFR) and histone H4 by Y72 peptide significantly reduced tumor growth. Furthermore, EGFR expression clinically correlates with histone H4-Y72 phosphorylation, H4-K20 monomethylation, and the Ki-67 proliferation marker. These findings uncover a mechanism by which EGFR transduces signal to chromatin to regulate DNA synthesis and repair.
组蛋白的翻译后修饰在许多生物功能中起着至关重要的作用。具体来说,组蛋白 H4-K20 甲基化对于 DNA 合成和修复至关重要。然而,人们对这些功能如何受到上游刺激的调节知之甚少。在这里,我们鉴定了组蛋白 H4 上 Y72 的一个酪氨酸磷酸化位点,该位点促进了组蛋白甲基转移酶(HMTases)SET8 和 SUV4-20H 的募集,从而增强其 K20 甲基化,从而促进 DNA 合成和修复。磷酸化缺陷型组蛋白 H4 突变体在 K20 甲基化方面存在缺陷,导致 DNA 合成减少、细胞周期进程延迟和 DNA 修复能力降低。通过 Y72 肽破坏表皮生长因子受体 (EGFR) 和组蛋白 H4 之间的相互作用,显著降低了肿瘤生长。此外,EGFR 表达与组蛋白 H4-Y72 磷酸化、H4-K20 单甲基化和 Ki-67 增殖标记物呈临床相关性。这些发现揭示了 EGFR 将信号转导至染色质以调节 DNA 合成和修复的机制。