Department of Physiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China, Department of Anesthesiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China, Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China, Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China, and Institute of Brain Research, Huazhong University of Science and Technology, Wuhan, 430030, China.
J Neurosci. 2014 May 7;34(19):6546-56. doi: 10.1523/JNEUROSCI.5119-13.2014.
Necrosis and apoptosis are two distinct types of mechanisms that mediate ischemic injury. But a signaling point of convergence between them has yet to be identified. Here, we show that activated death-associated protein kinase 1 (DAPK1), phosphorylates p53 at serine-23 (pS(23)) via a direct binding of DAPK1 death domain (DAPK1DD) to the DNA binding motif of p53 (p53DM). We uncover that the pS(23) acts as a functional version of p53 and mediates necrotic and apoptotic neuronal death; in the nucleus, pS(23) induces the expression of proapoptotic genes, such as Bax, whereas in the mitochondrial matrix, pS(23) triggers necrosis via interaction with cyclophilin D (CypD) in cultured cortical neurons from mice. Deletion of DAPK1DD (DAPK1(DDΔ)) or application of Tat-p53DM that interrupts DAPK1-p53 interaction blocks these dual pathways of pS(23) actions in mouse cortical neurons. Thus, the DAPK1-p53 interaction is a signaling point of convergence of necrotic and apoptotic pathways and is a desirable target for the treatment of ischemic insults.
细胞坏死和细胞凋亡是介导缺血性损伤的两种不同机制。但它们之间的交汇信号点尚未确定。在这里,我们发现激活的死亡相关蛋白激酶 1(DAPK1)通过 DAPK1 死亡结构域(DAPK1DD)与 p53 的 DNA 结合基序(p53DM)的直接结合,将 p53 丝氨酸-23(pS(23))磷酸化。我们揭示了 pS(23)作为 p53 的功能版本,介导了坏死和凋亡性神经元死亡;在核内,pS(23)诱导 Bax 等促凋亡基因的表达,而在线粒体基质中,pS(23)通过与小鼠皮质神经元中的亲环素 D(CypD)相互作用引发坏死。删除 DAPK1DD(DAPK1(DDΔ))或应用 Tat-p53DM (中断 DAPK1-p53 相互作用)可阻断 pS(23)在小鼠皮质神经元中的这两种作用途径。因此,DAPK1-p53 相互作用是坏死和凋亡途径的交汇信号点,是治疗缺血性损伤的理想靶点。