Department of Systems Biology and Division of Life Sciences, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Republic of Korea.
Department of Clinical Pharmacology and Therapeutics, Asan Medical Center, 88 Olympic-ro, 43-gil, Songpa-gu, Seoul 05505, Republic of Korea.
J Mol Biol. 2018 May 11;430(10):1521-1530. doi: 10.1016/j.jmb.2018.04.001. Epub 2018 Apr 7.
Dual-specificity tyrosine-regulated kinases (DYRKs) auto-phosphorylate a critical tyrosine residue in their activation loop and phosphorylate their substrate on serine and threonine residues. The auto-phosphorylation occurs intramolecularly and is a one-off event. DYRK3 is selectively expressed at a high level in hematopoietic cells and attenuates erythroblast development, leading to anemia. In the present study, we determined the crystal structure of the mature form of human DYRK3 in complex with harmine, an ATP competitive inhibitor. The crystal structure revealed a phosphorylation site, residue S350, whose phosphorylation increases the stability of DYRK3 and enhances its kinase activity. In addition, our structural and biochemical assays suggest that the N-terminal auto-phosphorylation accessory domain stabilizes the DYRK3 protein, followed by auto-phosphorylation of the tyrosine of the activation loop, which is important for kinase activity. Finally, our docking analysis provides information for the design of novel and potent therapeutics to treat anemia.
双特异性酪氨酸调节激酶（DYRKs）在其激活环中的关键酪氨酸残基上发生自身磷酸化，并在丝氨酸和苏氨酸残基上磷酸化其底物。这种自身磷酸化是分子内发生的一次性事件。DYRK3 在造血细胞中高度选择性表达，并抑制成红细胞发育，导致贫血。在本研究中，我们测定了与人 DYRK3 成熟形式与 harmine（一种 ATP 竞争性抑制剂）复合物的晶体结构。晶体结构揭示了一个磷酸化位点残基 S350，其磷酸化增加了 DYRK3 的稳定性并增强了其激酶活性。此外，我们的结构和生化分析表明，N 端自身磷酸化辅助结构域稳定 DYRK3 蛋白，随后是激活环酪氨酸的自身磷酸化，这对激酶活性很重要。最后，我们的对接分析为设计新型有效的治疗贫血的药物提供了信息。
