Villamayor Paula R, Gullón Julián, Quintela Luis, Sánchez-Quinteiro Pablo, Martínez Paulino, Robledo Diego
Departamento de Zooloxía, Xenética e Antropoloxía Física, Facultade de Veterinaria, Universidade de Santiago de Compostela, Lugo, Spain.
Departamento de Anatomía, Producción Animal e Ciencias Clínicas Veterinarias, Facultade de Veterinaria, Universidade de Santiago de Compostela, Lugo, Spain.
Front Mol Neurosci. 2022 Oct 21;15:1034254. doi: 10.3389/fnmol.2022.1034254. eCollection 2022.
Chemosensory cues are vital for social and sexual behaviours and are primarily detected and processed by the vomeronasal system (VNS), whose plastic capacity has been investigated in mice. However, studying chemosensory plasticity outside of laboratory conditions may give a more realistic picture of how the VNS adapts to a changing environment. Rabbits are a well-described model of chemocommunication since the discovery of the rabbit mammary pheromone and their vomeronasal organ (VNO) transcriptome was recently characterised, a first step to further study plasticity-mediated transcriptional changes. In this study, we assessed the plastic capacity of the rabbit male and female VNO under sex-separation vs. sex-combined scenarios, including adults and juveniles, to determine whether the rabbit VNO is plastic and, if so, whether such plasticity is already established at early stages of life. First, we characterised the number of differentially expressed genes (DEGs) between the VNO of rabbit male and female under sex-separation and compared it to sex-combined individuals, both in adults and juveniles, finding that differences between male and female were larger in a sex-separated scenario. Secondly, we analysed the number of DEGs between sex-separated and sex-combined scenarios, both in males and females. In adults, both sexes showed a high number of DEGs while in juveniles only females showed differences. Additionally, the vomeronasal receptor genes were strikingly downregulated in sex-separated adult females, whereas in juveniles upregulation was shown for the same condition, suggesting a role of VRs in puberty onset. Finally, we described the environment-modulated plastic capacity of genes involved in reproduction, immunity and VNO functional activity, including G-protein coupled receptors. Our results show that sex-separation induces sex- and stage-specific gene expression differences in the VNO of male and female rabbit, both in adults and juveniles. These results bring out for the first time the plastic capacity of the rabbit VNO, supporting its functional adaptation to specifically respond to a continuous changing environment. Finally, species-specific differences and individual variability should always be considered in VNO studies and overall chemocommunication research.
化学感应线索对社交和性行为至关重要，主要由犁鼻器系统（VNS）进行检测和处理，其可塑性已在小鼠中得到研究。然而，在实验室条件之外研究化学感应可塑性，可能会更真实地展现VNS如何适应不断变化的环境。自兔乳腺信息素被发现以来，兔子就是一个被充分描述的化学通讯模型，并且其犁鼻器（VNO）转录组最近已被表征，这是进一步研究可塑性介导的转录变化的第一步。在本研究中，我们评估了兔雄性和雌性VNO在性别分离与性别组合情况下的可塑性，包括成年兔和幼年兔，以确定兔VNO是否具有可塑性，如果是，这种可塑性是否在生命早期就已确立。首先，我们对成年兔和幼年兔在性别分离情况下雄性和雌性VNO之间的差异表达基因（DEG）数量进行了表征，并将其与性别组合个体进行比较，发现雄性和雌性之间的差异在性别分离情况下更大。其次，我们分析了性别分离和性别组合情况下雄性和雌性的DEG数量。在成年兔中，两性都显示出大量的DEG，而在幼年兔中只有雌性显示出差异。此外，犁鼻器受体基因在性别分离的成年雌性中显著下调，而在幼年兔中相同情况下则显示上调，这表明犁鼻器受体在青春期开始中起作用。最后，我们描述了参与生殖、免疫和VNO功能活动的基因（包括G蛋白偶联受体）的环境调节可塑性。我们的结果表明，性别分离在成年兔和幼年兔的雄性和雌性VNO中诱导了性别和阶段特异性的基因表达差异。这些结果首次揭示了兔VNO的可塑性，支持其功能适应以特异性应对不断变化的环境。最后，在VNO研究和整体化学通讯研究中，应始终考虑物种特异性差异和个体变异性。
