Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213.
Department of Cell Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213.
eNeuro. 2018 Jan 10;5(6). doi: 10.1523/ENEURO.0466-18.2018. eCollection 2018 Nov-Dec.
While PTEN-induced kinase 1 (PINK1) is well characterized for its role in mitochondrial homeostasis, much less is known concerning its ability to prevent synaptodendritic degeneration. Using unbiased proteomic methods, we identified valosin-containing protein (VCP) as a major PINK1-interacting protein. RNAi studies demonstrate that both VCP and its cofactor NSFL1C/p47 are necessary for the ability of PINK1 to increase dendritic complexity. Moreover, PINK1 regulates phosphorylation of p47, but not the VCP co-factor UFD1. Although neither VCP nor p47 interact directly with PKA, we found that PINK1 binds and phosphorylates the catalytic subunit of PKA at T197 [PKA(pT197)], a site known to activate the PKA holoenzyme. PKA in turn phosphorylates p47 at a novel site (S176) to regulate dendritic complexity. Given that PINK1 physically interacts with both the PKA holoenzyme and the VCP-p47 complex to promote dendritic arborization, we propose that PINK1 scaffolds a novel PINK1-VCP-PKA-p47 signaling pathway to orchestrate dendritogenesis in neurons. These findings highlight an important mechanism by which proteins genetically implicated in Parkinson's disease (PD; PINK1) and frontotemporal dementia (FTD; VCP) interact to support the health and maintenance of neuronal arbors.
虽然 PTEN 诱导的激酶 1(PINK1)因其在线粒体动态平衡中的作用而得到很好的描述,但对于其防止突触树突退化的能力知之甚少。我们使用无偏蛋白组学方法鉴定了泛素结合酶(VCP)是 PINK1 的主要相互作用蛋白。RNAi 研究表明,VCP 及其共因子 NSFL1C/p47 对于 PINK1 增加树突复杂性的能力都是必需的。此外,PINK1 调节 p47 的磷酸化,但不调节 VCP 共因子 UFD1。尽管 VCP 或 p47 都不与 PKA 直接相互作用,但我们发现 PINK1 结合并磷酸化 PKA 的催化亚基 T197[PKA(pT197)],该位点已知可激活 PKA 全酶。PKA 反过来在一个新的位点(S176)磷酸化 p47 以调节树突复杂性。鉴于 PINK1 与 PKA 全酶和 VCP-p47 复合物都相互作用以促进树突分支,我们提出 PINK1 支架了一个新的 PINK1-VCP-PKA-p47 信号通路来协调神经元中的树突发生。这些发现强调了一种重要的机制,即遗传上与帕金森病(PD;PINK1)和额颞叶痴呆(FTD;VCP)相关的蛋白质相互作用以支持神经元树突的健康和维持。