A bidirectional switch in the Shank3 phosphorylation state biases synapses toward up- or downscaling.
A bidirectional switch in the Shank3 phosphorylation state biases synapses toward up- or downscaling.
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DOI：
10.7554/elife.74277
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发表时间：
2022-04-26
期刊：
影响因子：
7.7
通讯作者：
Turrigiano, Gina G.
中科院分区：
文献类型：
--
作者：
Wu, Chi-Hong;Tatavarty, Vedakumar;Jean Beltran, Pierre M.;Guerrero, Andrea A.;Keshishian, Hasmik;Krug, Karsten;MacMullan, Melanie A.;Li, Li;Carr, Steven A.;Cottrell, Jeffrey R.;Turrigiano, Gina G.
动态平衡的突触可塑性需要突触信号和支架网络的广泛重构，但翻译后修饰在这一过程中的作用尚未得到系统研究。通过对小鼠新皮质神经元中磷酸蛋白质组的深层次定量分析，我们发现在突触放大和缩小的过程中，存在着广泛的和时间上复杂的变化。我们观察到424个双向调节的磷酸盐位点高度富含突触相关蛋白，包括自闭症谱系障碍相关突触支架蛋白Shank3中的S1539。通过免疫亲和对从大鼠新皮质神经元分离的Shank3进行平行蛋白质组学分析，我们发现了两个在放大过程中持续低磷酸化，在缩小过程中短暂过度磷酸化的位置：一个(大鼠S1615)对应于小鼠的S1539，以及第二个高度保守的位置，大鼠S1586。这些位点的磷酸化状态改变了Scaling过程中Shank3的突触定位，而通过PP2A活性去磷酸化这些位点对于维持突触的放大是必不可少的。最后，这些位点的仿磷突变阻止了放大而不是缩小，而缺磷突变阻止了缩小而不是扩大。这些突变不影响基线突触强度，表明它们开启而不是驱动突触伸缩的诱导。因此，Shank3的S1586和S1615上的低磷酸化和高磷酸化之间的活性依赖的切换分别使放大或缩小成为可能。总之，我们的数据表明，活性依赖的磷酸蛋白质组动力学对于突触支架的功能重组非常重要，并可以使突触倾向于向上或向下的稳态可塑性。
Homeostatic synaptic plasticity requires widespread remodeling of synaptic signaling and scaffolding networks, but the role of post-translational modifications in this process has not been systematically studied. Using deep-scale quantitative analysis of the phosphoproteome in mouse neocortical neurons, we found widespread and temporally complex changes during synaptic scaling up and down. We observed 424 bidirectionally modulated phosphosites that were strongly enriched for synapse-associated proteins, including S1539 in the autism spectrum disorder-associated synaptic scaffold protein Shank3. Using a parallel proteomic analysis performed on Shank3 isolated from rat neocortical neurons by immunoaffinity, we identified two sites that were persistently hypophosphorylated during scaling up and transiently hyperphosphorylated during scaling down: one (rat S1615) that corresponded to S1539 in mouse, and a second highly conserved site, rat S1586. The phosphorylation status of these sites modified the synaptic localization of Shank3 during scaling protocols, and dephosphorylation of these sites via PP2A activity was essential for the maintenance of synaptic scaling up. Finally, phosphomimetic mutations at these sites prevented scaling up but not down, while phosphodeficient mutations prevented scaling down but not up. These mutations did not impact baseline synaptic strength, indicating that they gate, rather than drive, the induction of synaptic scaling. Thus, an activity-dependent switch between hypo- and hyperphosphorylation at S1586 and S1615 of Shank3 enables scaling up or down, respectively. Collectively, our data show that activity-dependent phosphoproteome dynamics are important for the functional reconfiguration of synaptic scaffolds and can bias synapses toward upward or downward homeostatic plasticity.
DOI：
10.1016/j.bbrc.2009.10.167
发表时间：
2010-01-01
影响因子：
3.1
作者：
Dosemeci, Ayse;Jaffe, Howard
通讯作者：
Jaffe, Howard