Single-cell RNA sequencing of mouse olfactory sensory neurons

The goal of this study was to identify those odorant receptors conferring a response to indole or related odorants (2-methylindole, 3-methylindole, 6-methylindole, 2-methoxynaphthalene, and Lilyflore®) in olfactory sensory neurons (OSNs). Odorants were sequentially delivered to dissociated OSNs, and six OSNs with three different response profiles were isolated for transcriptome analysis. OSN1 and OSN2 responded to indole, 2-methylindole, 3-methylindole, and 6-methylindole; OSN3 and OSN4 responded to Indole and 2-methoxynaphthalene; OSN5 and OSN6 responded to indole, 3-methylindole, 6-methylindole, and 2-methoxynaphthalene. RNA transcripts encoding Olfr740 (OSN1, OSN2), Olfr741 (OSN3, OSN4), and Olfr743 (OSN5, OSN6) were retrieved, with high level expression of a single OR transcript in each OSN. The expression of mature OSN markers OMP, Golf, Adcy3, Cnga2 and Rtp1 was also confirmed. Individual olfactory sensory neuron mRNA profiles of 6 week old wild type (C57BL/6) mice were generated by single-cell RNA-Seq via the Cel-Seq2 method and sequenced on the Illumina NovaSeq 6000.本研究旨在鉴定嗅觉感觉神经元（olfactory sensory neurons, OSNs）中可介导对吲哚及相关气味物质（2-甲基吲哚、3-甲基吲哚、6-甲基吲哚、2-甲氧基萘及Lilyflore®）产生应答的气味受体。将气味物质依次施加于解离后的嗅觉感觉神经元，筛选得到具有三种不同应答谱型的6个嗅觉感觉神经元用于转录组分析。其中，OSN1与OSN2可对吲哚、2-甲基吲哚、3-甲基吲哚及6-甲基吲哚产生应答；OSN3与OSN4可对吲哚及2-甲氧基萘产生应答；OSN5与OSN6可对吲哚、3-甲基吲哚、6-甲基吲哚及2-甲氧基萘产生应答。后续检索到分别编码Olfr740（对应OSN1、OSN2）、Olfr741（对应OSN3、OSN4）及Olfr743（对应OSN5、OSN6）的RNA转录本，且每个嗅觉感觉神经元均单一高表达一种气味受体转录本。同时验证了成熟嗅觉感觉神经元标志物OMP、Golf、Adcy3、Cnga2及Rtp1的表达。本数据集通过Cel-Seq2单细胞RNA测序技术，构建了6周龄野生型（C57BL/6）小鼠的单个嗅觉感觉神经元mRNA表达谱，并在Illumina NovaSeq 6000测序平台完成测序。