Arc expression identifies the lateral amygdala fear memory trace.
Arc expression identifies the lateral amygdala fear memory trace.
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DOI：
10.1038/mp.2015.18
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发表时间：
2016-03
影响因子：
11
通讯作者：
Kushner SA
中科院分区：
文献类型：
--
作者：
Gouty-Colomer LA;Hosseini B;Marcelo IM;Schreiber J;Slump DE;Yamaguchi S;Houweling AR;Jaarsma D;Elgersma Y;Kushner SA
记忆是在稀疏分布的神经元集合中编码的。然而，在记忆痕迹中神经元的定义细胞特性仍然不完全清楚。使用基于荧光的Arc报告器，我们能够直观地识别在听觉恐惧条件反射期间激活的外侧杏仁核（LA）神经元的不同子集。我们发现表达arc的神经元具有增强的内在兴奋性，并优先被招募到新编码的记忆痕迹中。此外，在恐惧条件反射过程中，丘脑输入到LA的突触增强是学习特异性的，突触后介导的，高度局限于表达arc的神经元。综上所述，我们的研究结果证实了立即早期基因Arc作为恐惧学习过程中LA神经元集合的分子标记。此外，这些结果建立了一个恐惧记忆形成的模型，其中内在的兴奋性决定了神经元的选择，而学习相关的编码则由突触可塑性控制。
Memories are encoded within sparsely distributed neuronal ensembles. However, the defining cellular properties of neurons within a memory trace remain incompletely understood. Using a fluorescence-based Arc reporter, we were able to visually identify the distinct subset of lateral amygdala (LA) neurons activated during auditory fear conditioning. We found that Arc-expressing neurons have enhanced intrinsic excitability and are preferentially recruited into newly encoded memory traces. Furthermore, synaptic potentiation of thalamic inputs to the LA during fear conditioning is learning-specific, postsynaptically mediated and highly localized to Arc-expressing neurons. Taken together, our findings validate the immediate-early gene Arc as a molecular marker for the LA neuronal ensemble recruited during fear learning. Moreover, these results establish a model of fear memory formation in which intrinsic excitability determines neuronal selection, whereas learning-related encoding is governed by synaptic plasticity.