Gürth Clara-Marie, Dankovich Tal M, Rizzoli Silvio O, D'Este Elisa
Department of NanoBiophotonics, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077, Göttingen, Germany.
Department of Optical Nanoscopy, Max Planck Institute for Medical Research, Jahnstr. 29, 69120, Heidelberg, Germany.
Sci Rep. 2020 Nov 25;10(1):20576. doi: 10.1038/s41598-020-77260-2.
Neurons are highly asymmetric cells that span long distances and need to react promptly to local demands. Consequently, neuronal secretory pathway elements are distributed throughout neurites, specifically in post-synaptic compartments, to enable local protein synthesis and delivery. Whether and how changes in local synaptic activity correlate to post-synaptic secretory elements is still unclear. To assess this, we used STED nanoscopy and automated quantitative image analysis of post-synaptic markers of the endoplasmic reticulum, ER-Golgi intermediate compartment, trans-Golgi network, and spine apparatus. We found that the distribution of these proteins was dependent on pre-synaptic activity, measured as the amount of recycling vesicles. Moreover, their abundance correlated to both pre- and post-synaptic markers of synaptic strength. Overall, the results suggest that in small, low-activity synapses the secretory pathway components are tightly clustered in the synaptic area, presumably to enable rapid local responses, while bigger synapses utilise secretory machinery components from larger, more diffuse areas.
神经元是高度不对称的细胞，其跨度很长，需要对局部需求迅速做出反应。因此，神经元分泌途径元件分布于整个神经突，特别是在突触后区室，以实现局部蛋白质合成和递送。局部突触活动的变化是否以及如何与突触后分泌元件相关仍不清楚。为了评估这一点，我们使用了受激发射损耗（STED）纳米显微镜以及对内质网、内质网-高尔基体中间区室、反式高尔基体网络和棘器的突触后标记物进行自动定量图像分析。我们发现这些蛋白质的分布取决于突触前活动，以循环囊泡的数量来衡量。此外，它们的丰度与突触强度的突触前和突触后标记物均相关。总体而言，结果表明在小的、低活性突触中，分泌途径成分紧密聚集在突触区域，大概是为了实现快速的局部反应，而较大的突触则利用来自更大、更分散区域的分泌机制成分。
