Loizeau Mathieu, Angelova Alexandra, Cremer Harold, Platel Jean-Claude
Aix Marseille University, CNRS, IBDM, UMR 7288, Turing Centre for Living Systems, Marseille, France.
Aix-Marseille University, INSERM, INMED, UMR 1249, Turing Centre for Living Systems, Marseille, France.
iScience. 2025 Jul 18;28(8):113161. doi: 10.1016/j.isci.2025.113161. eCollection 2025 Aug 15.
The olfactory system has been extensively studied from both anatomical and functional perspectives. The glomerular layer of the olfactory bulb is the first brain region to integrate olfactory signals, creating a topographic representation of odor identity. However, how sensory information-such as odor identity and concentration-is transformed within a glomerular unit remains unclear. To address this, we investigated how odor information is processed at the intraglomerular network level using genetic labeling, imaging, and computational methods. We showed that glomerular glutamatergic neurons, known as external tufted cells (ETCs), exhibit distinct responses to different odors and concentrations. Furthermore, structural and functional imaging of the sister ETCs revealed distinct intraglomerular neuronal ensembles influenced by odor identity and concentration. These findings suggest that ETCs could encode both odor identity and concentration simultaneously within glomerular modules, suggesting an early mechanism for odor decorrelation.
嗅觉系统已经从解剖学和功能学角度进行了广泛研究。嗅球的肾小球层是第一个整合嗅觉信号的脑区，形成气味特征的拓扑表征。然而，诸如气味特征和浓度等感觉信息在一个肾小球单元内是如何转换的仍不清楚。为了解决这个问题，我们使用基因标记、成像和计算方法研究了气味信息在肾小球内网络水平上是如何处理的。我们发现，被称为外侧簇状细胞（ETC）的肾小球谷氨酸能神经元对不同的气味和浓度表现出不同的反应。此外，对姊妹ETC的结构和功能成像揭示了受气味特征和浓度影响的不同的肾小球内神经元集群。这些发现表明，ETC可以在肾小球模块内同时编码气味特征和浓度，这提示了一种气味去相关的早期机制。
