Glaser Nicolas, Gallot Aurore, Legeai Fabrice, Harry Myriam, Kaiser Laure, Le Ru Bruno, Calatayud Paul-André, Jacquin-Joly Emmanuelle
INRA, UMR 1392, Institut d'Ecologie et des Sciences de l'Environnement de Paris, Route de Saint-Cyr, F-78026 Versailles Cedex, France; UMR Evolution, Génomes, Comportement et Ecologie, IRD, CNRS, Université Paris Sud, Campus CNRS, 91198 Gif-sur-Yvette Cedex, France.
INRA, UMR 1392, Institut d'Ecologie et des Sciences de l'Environnement de Paris, Route de Saint-Cyr, F-78026 Versailles Cedex, France; IRISA, équipe GenScale, Campus universitaire de Beaulieu, 35042 Rennes Cedex, France.
Insect Biochem Mol Biol. 2015 Oct;65:28-34. doi: 10.1016/j.ibmb.2015.07.008. Epub 2015 Aug 24.
Among the proposed mechanisms of local adaptation to different ecological environments, transcriptional changes may play an important role. In this study, we investigated whether such variability occurred within the chemosensory organs of a herbivorous insect, for which chemosensation guides most of its host preferences. A European and an African population of the noctuid Sesamia nonagrioides that display significant differences in their ecological preferences were collected on Zea mays and Typha domingensis, respectively. RNAseq were used between the two populations for digital expression profiling of chemosensory organs from larval antennae and palps. Preliminary data on adult female antennae and ovipositors were also collected. We found 6,550 differentially expressed transcripts in larval antennae and palps. Gene ontology enrichment analyses suggested that transcriptional activity was overrepresented in the French population and that virus and defense activities were overrepresented in the Kenyan population. In addition, we found differential expression of a variety of cytochrome P450s, which may be linked to the different host-plant diets. Looking at olfactory genes, we observed differential expression of numerous candidate odorant-binding proteins, chemosensory proteins, and one olfactory receptor, suggesting that differences in olfactory sensitivity participate in insect adaptation.
在提出的局部适应不同生态环境的机制中，转录变化可能起重要作用。在本研究中，我们调查了这种变异性是否发生在一种食草昆虫的化学感觉器官内，对该昆虫而言，化学感觉决定了其大部分宿主偏好。分别在玉米和香蒲上采集了欧洲和非洲种群的夜蛾Sesamia nonagrioides，它们在生态偏好上存在显著差异。对这两个种群的幼虫触角和触须的化学感觉器官进行RNA测序以进行数字表达谱分析。还收集了成年雌性触角和产卵器的初步数据。我们在幼虫触角和触须中发现了6550个差异表达的转录本。基因本体富集分析表明，转录活性在法国种群中过度表达，而病毒和防御活性在肯尼亚种群中过度表达。此外，我们发现多种细胞色素P450存在差异表达，这可能与不同的宿主植物饮食有关。观察嗅觉基因，我们观察到许多候选气味结合蛋白、化学感觉蛋白和一种嗅觉受体存在差异表达，这表明嗅觉敏感性的差异参与了昆虫的适应性。
