人类SETDB1蛋白赖氨酸867位点的泛素化上调其组蛋白H3赖氨酸9（H3K9）甲基转移酶活性。
Ubiquitination of Lysine 867 of the Human SETDB1 Protein Upregulates Its Histone H3 Lysine 9 (H3K9) Methyltransferase Activity.
作者信息
Ishimoto Kenji, Kawamata Natsuko, Uchihara Yoshie, Okubo Moeka, Fujimoto Reiko, Gotoh Eiko, Kakinouchi Keisuke, Mizohata Eiichi, Hino Nobumasa, Okada Yoshiaki, Mochizuki Yasuhiro, Tanaka Toshiya, Hamakubo Takao, Sakai Juro, Kodama Tatsuhiko, Inoue Tsuyoshi, Tachibana Keisuke, Doi Takefumi
机构信息
Laboratory of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka, Japan.
Laboratory for System Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Meguro, Tokyo, Japan.
出版信息
PLoS One. 2016 Oct 31;11(10):e0165766. doi: 10.1371/journal.pone.0165766. eCollection 2016.
Posttranslational modifications (PTMs) of proteins play a crucial role in regulating protein-protein interactions, enzyme activity, subcellular localization, and stability of the protein. SET domain, bifurcated 1 (SETDB1) is a histone methyltransferase that regulates the methylation of histone H3 on lysine 9 (H3K9), gene silencing, and transcriptional repression. The C-terminal region of SETDB1 is a key site for PTMs, and is essential for its enzyme activity in mammalian and insect cells. In this study, we aimed to evaluate more precisely the effect of PTMs on the H3K9 methyltransferase activity of SETDB1. Using mass spectrometry analysis, we show that the C-terminal region of human SETDB1 purified from insect cells is ubiquitinated. We also demonstrate that the ubiquitination of lysine 867 of the human SETDB1 is necessary for full H3K9 methyltransferase activity in mammalian cells. Finally, we show that SETDB1 ubiquitination regulates the expression of its target gene, serpin peptidase inhibitor, clade E, member 1 (SERPINE1) by methylating H3K9. These results suggest that the ubiquitination of SETDB1 at lysine 867 controls the expression of its target gene by activating its H3K9 methyltransferase activity.
蛋白质的翻译后修饰（PTMs）在调节蛋白质-蛋白质相互作用、酶活性、亚细胞定位和蛋白质稳定性方面发挥着关键作用。SET结构域分叉1（SETDB1）是一种组蛋白甲基转移酶，可调节组蛋白H3赖氨酸9（H3K9）的甲基化、基因沉默和转录抑制。SETDB1的C末端区域是PTMs的关键位点，对其在哺乳动物和昆虫细胞中的酶活性至关重要。在本研究中，我们旨在更精确地评估PTMs对SETDB1的H3K9甲基转移酶活性的影响。通过质谱分析，我们发现从昆虫细胞中纯化的人SETDB1的C末端区域发生了泛素化。我们还证明，人SETDB1赖氨酸867的泛素化对于其在哺乳动物细胞中的完整H3K9甲基转移酶活性是必需的。最后，我们表明SETDB1泛素化通过甲基化H3K9来调节其靶基因丝氨酸蛋白酶抑制剂E家族成员1（SERPINE1）的表达。这些结果表明，SETDB1赖氨酸867处的泛素化通过激活其H3K9甲基转移酶活性来控制其靶基因的表达。
Zotero 插件