中国科技大学陶长路课题组的一项最新研究提出了低温电子断层扫描揭示天然海马突触的亚细胞结构。该项研究成果发表在2026年1月5日出版的《神经科学通报》上。

小组利用冷冻电镜定量分析了300多个完整海马突触的亚细胞特征，发现：(1)大量兴奋性突触（32%）定位于树突轴，而相对较高比例的抑制性突触（35%）定位于树突棘，突触间隙显示出不同的几何形状；(2)突触前钮扣内富含致密核囊泡、无膜致密颗粒、空网格蛋白笼等多种结构；(3)线粒体普遍存在于突触前和突触后区域，突触后线粒体基质颗粒的丰度更高。这些发现为海马体突触的结构组织提供了一个全面的视角，并提出了控制其亚细胞结构的基本原理。

研究人员表示，突触是神经元回路的核心组成部分，它依靠精确的超微结构和分子组织来促进量子传输和可塑性，这是大脑信息处理和存储的基础。低温电子断层扫描（cryo-ET）已成为阐明突触纳米结构的有力工具，但先前的研究主要集中在突触囊泡和突触后受体上，而对其他关键成分的探索不足。

附：英文原文

Title: Subcellular Structures in Native Hippocampal Synapses Revealed by Cryo-electron Tomography

Author: Tian, Chong-Li, Qi, Lei, Lu, Zhen-Hang, Liu, Shuo, Gu, Min-Ling, Huang, Wen-Lan, Yan, Yi-Tong, Liu, Yun-Tao, Wu, Jing, Wang, Peiyi, Zhou, Z. Hong, Bi, Guo-Qiang, Lau, Pak-Ming, Tao, Chang-Lu

Issue&Volume: 2026-01-05

Abstract: Synapses, the core components of neuronal circuits, rely on precise ultrastructural and molecular organization to facilitate quantal transmission and plasticity, which underpin brain information processing and storage. Cryo-electron tomography (cryo-ET) has emerged as a powerful tool for elucidating the nanoscale architecture of synapses, yet prior studies have largely focused on synaptic vesicles and postsynaptic receptors, leaving other critical components underexplored. Here, we employed cryo-ET to quantitatively analyze subcellular features across over 300 intact hippocampal synapses, revealing: (1) A significant proportion of excitatory synapses (32%) localized to dendritic shafts, while a relatively high proportion of inhibitory synapses targeted dendritic spines (35%), with synaptic clefts displaying four distinct geometries; (2) Diverse structures, including dense core vesicles, membraneless dense granules, and empty clathrin cages were enriched within presynaptic boutons; (3) Mitochondria prevalent in both pre- and postsynaptic regions, showing higher abundance of mitochondrial matrix granules postsynaptically. These findings provide a comprehensive view of the structural organization within hippocampal synapses and suggest fundamental principles governing their subcellular architecture.

DOI: 10.1007/s12264-025-01569-z

Source: https://link.springer.com/article/10.1007/s12264-025-01569-z