美国哥伦比亚大学Attila Losonczy和Franck Polleux共同合作，近期取得重要工作进展。他们报道了海马神经元特征选择性的突触基础。相关研究成果2024年12月18日在线发表于《自然》杂志上。

据介绍，神经科学的一个核心问题是，突触可塑性如何影响行为动物神经元的特征选择性。海马CA1区锥体神经元，通过形成称为位置场的空间和情境选择性感受野，表现出最显著的特征选择性形式之一，该感受野是研究学习和记忆突触基础的模型。

各种形式的突触可塑性已被提出作为位置场出现的细胞底物。然而，尽管进行了数十年的研究，人们对突触可塑性如何成为，位置场形成和记忆编码的基础的理解仍然有限，主要是由于缺乏工具和技术上的挑战，即在清醒行为的动物中，以单个神经元的分辨率来可视化突触可塑性。

为了解决这个问题，研究人员开发了一种全光方法，来监测空间导航过程中单个CA1锥体神经元，在诱导位置场前后树突棘的时空调谐和突触重量变化。研究人员发现了一个时间不对称的突触可塑性核，这是由围绕位置场诱导的突触权重的双向修改引起的。这一研究确定了基底树突和斜树突之间突触可塑性的幅度，和时间表达的室特异性差异。

总之，这一研究结果提供了实验证据，将突触可塑性与海马神经元中空间选择性的快速出现联系起来，这是情景记忆的关键先决条件。

附：英文原文

Title: Synaptic basis of feature selectivity in hippocampal neurons

Author: Gonzalez, Kevin C., Negrean, Adrian, Liao, Zhenrui, Terada, Satoshi, Zhang, Guofeng, Lee, Sungmoo, csai, Katalin, Rzsa, Balzs J., Lin, Michael Z., Polleux, Franck, Losonczy, Attila

Issue&Volume: 2024-12-18

Abstract: A central question in neuroscience is how synaptic plasticity shapes the feature selectivity of neurons in behaving animals1. Hippocampal CA1 pyramidal neurons display one of the most striking forms of feature selectivity by forming spatially and contextually selective receptive fields called place fields, which serve as a model for studying the synaptic basis of learning and memory. Various forms of synaptic plasticity have been proposed as cellular substrates for the emergence of place fields. However, despite decades of work, our understanding of how synaptic plasticity underlies place-field formation and memory encoding remains limited, largely due to a shortage of tools and technical challenges associated with the visualization of synaptic plasticity at the single-neuron resolution in awake behaving animals. To address this, we developed an all-optical approach to monitor the spatiotemporal tuning and synaptic weight changes of dendritic spines before and after the induction of a place field in single CA1 pyramidal neurons during spatial navigation. We identified a temporally asymmetric synaptic plasticity kernel resulting from bidirectional modifications of synaptic weights around the induction of a place field. Our work identified compartment-specific differences in the magnitude and temporal expression of synaptic plasticity between basal dendrites and oblique dendrites. Our results provide experimental evidence linking synaptic plasticity to the rapid emergence of spatial selectivity in hippocampal neurons, a critical prerequisite for episodic memory.

DOI: 10.1038/s41586-024-08325-9

Source: https://www.nature.com/articles/s41586-024-08325-9