Single-cell RNA sequencing reveals distinct transcriptional features of the purinergic signaling in mouse trigeminal ganglion

Trigeminal ganglion (TG) is the first station of sensory pathways in the orofacial region. The TG neurons communicate with satellite glial cells (SGCs), macrophages and other cells forming a functional unit that is responsible for processing of orofacial sensory information. Purinergic signaling, one of the most widespread autocrine and paracrine pathways, plays a crucial role in intercellular communication. The multidirectional action of purinergic signaling in different cell types contributes to the neuromodulation and orofacial sensation. To fully understand the purinergic signaling in these processes, it is essential to determine the shared and unique expression patterns of genes associated with purinergic signaling in different cell types. Here, we performed single-cell RNA sequencing of 22,969 cells isolated from normal mouse TGs. We identified 18 distinct cell populations, including 6 neuron subpopulations, 3 glial subpopulations, 7 immune cell subpopulations, fibroblasts, and endothelial cells. We also revealed the transcriptional features of genes associated with purinergic signaling, including purinergic receptors, extracellular adenosine triphosphate (eATP) release channels, eATP metabolism-associated enzymes, and eATP transporters) in each cell type. Our results have important implications for understanding and predicting the cell type-specific roles of the purinergic signaling in orofacial signal processing in the trigeminal primary sensory system. Bilateral TGs of 5 normal mouse were harvested (n=10) and performed scRNA-seq. We aimed to identify distinct cellular populations in TG and describe the transcriptional features of the genes associated with the purinergic signaling in each cell type using scRNA-seq.三叉神经节（Trigeminal ganglion, TG）是口面部区域感觉传导通路的第一站。TG神经元与卫星胶质细胞（satellite glial cells, SGCs）、巨噬细胞及其他细胞共同构成功能单元，负责处理口面部感觉信息。嘌呤能信号传导是分布最为广泛的自分泌与旁分泌通路之一，在细胞间通讯中发挥核心作用。嘌呤能信号在不同细胞类型中的多向调控效应，参与神经调节与口面部感觉的形成过程。若要全面解析该过程中嘌呤能信号传导的机制，明确嘌呤能信号相关基因在不同细胞类型中的共性与特异性表达模式至关重要。 本研究对从正常小鼠三叉神经节中分离得到的22969个细胞开展了单细胞RNA测序（single-cell RNA sequencing, scRNA-seq）。共鉴定出18个独立细胞群，包括6种神经元亚群、3种胶质细胞亚群、7种免疫细胞亚群，以及成纤维细胞与内皮细胞。本研究同时揭示了各类细胞中嘌呤能信号相关基因的转录特征，涵盖嘌呤能受体、细胞外三磷酸腺苷（extracellular adenosine triphosphate, eATP）释放通道、eATP代谢相关酶类及eATP转运蛋白。本研究结果对于理解和预测三叉神经初级感觉系统中，嘌呤能信号传导在口面部信号处理过程中的细胞类型特异性调控作用具有重要参考价值。 本研究收集了5只正常小鼠的双侧三叉神经节（n=10）并进行scRNA-seq实验，旨在通过该技术鉴定TG内的不同细胞群，并阐明各类细胞中嘌呤能信号相关基因的转录特征。