Data_Sheet_1.XLSX

Mammalian olfaction depends on chemosensory neurons of the main olfactory epithelia (MOE), and/or of the accessory olfactory epithelia in the vomeronasal organ (VNO). Thus, we have generated the VNO and MOE transcriptomes and the nasal cavity proteome of the house mouse, Mus musculus musculus. Both transcriptomes had low levels of sexual dimorphisms, while the soluble proteome of the nasal cavity revealed high levels of sexual dimorphism similar to that previously reported in tears and saliva. Due to low levels of sexual dimorphism in the olfactory receptors in MOE and VNO, the sex-specific sensing seems less likely to be dependent on receptor repertoires. However, olfaction may also depend on a continuous removal of background compounds from the sites of detection. Odorant binding proteins (OBPs) are thought to be involved in this process and in our study Obp transcripts were most expressed along other lipocalins (e.g., Lcn13, Lcn14) and antimicrobial proteins. At the level of proteome, OBPs were highly abundant with only few being sexually dimorphic. We have, however, detected the major urinary proteins MUP4 and MUP5 in males and females and the male-biased central/group-B MUPs that were thought to be abundant mainly in the urine. The exocrine gland-secreted peptides ESP1 and ESP22 were male-biased but not male-specific in the nose. For the first time, we demonstrate that the expression of nasal lipocalins correlates with antimicrobial proteins thus suggesting that their individual variation may be linked to evolvable mechanisms that regulate natural microbiota and pathogens that regularly enter the body along the ‘eyes-nose-oral cavity’ axis.

哺乳动物嗅觉依赖于主嗅觉上皮（main olfactory epithelia, MOE）以及/或犁鼻器（vomeronasal organ, VNO）中的副嗅觉上皮。据此，我们针对小家鼠（Mus musculus musculus）构建了其犁鼻器与主嗅觉上皮的转录组，以及鼻腔的蛋白质组。两种转录组的性别二态性水平均较低，而鼻腔可溶性蛋白质组呈现出高度的性别二态性，这与此前在泪液与唾液中报道的结果类似。鉴于主嗅觉上皮与犁鼻器内嗅觉受体的性别二态性水平较低，性别特异性嗅觉感知似乎不太可能依赖于受体组库。不过，嗅觉或许还依赖于对检测位点处背景化合物的持续清除。气味结合蛋白（odorant binding proteins, OBPs）被认为参与这一过程，在本研究中，Obp转录本与其他脂质运载蛋白（如Lcn13、Lcn14）及抗菌蛋白的表达量最高。在蛋白质组层面，气味结合蛋白丰度极高，但仅少数存在性别二态性。不过，我们在雌雄个体鼻腔中均检测到了主要尿蛋白（major urinary proteins, MUP）4与MUP5，以及此前被认为主要在尿液中高丰度表达的雄性偏好型B组/中枢型主要尿蛋白。外分泌腺分泌肽ESP1与ESP22在鼻腔中呈现雄性偏好性，但并非雄性特异性。本研究首次证实，鼻腔脂质运载蛋白的表达与抗菌蛋白存在相关性，这提示它们的个体差异或许与可演化的调控机制相关，该机制可调控经由“眼-鼻-口腔”轴持续侵入机体的自然菌群与病原体。