Insect cuticle lipid formation and the impact of cuticle lipids on the ecological adaptability

昆虫角质层脂质提供了有效的双面屏障，防止脱水和外源性物质的渗透，确保在潜在的不利环境条件下，如高温和低湿度下的生存。因此，它们对昆虫的生态适应性有很大的影响。然而，迄今为止，昆虫表皮脂质生物学的分子和遗传方面的研究很少。这种忽视最终严重制约了基于角质层脂类生物学的绿色生态调控技术的发展。在本提案中，我们打算使用农业害虫飞蝗（Locusta migratoria（飞蝗）和模式昆虫果蝇（Drosophila melanogaster）（果蝇）的研究，主要包括以下几个方面：1）利用染料渗透法和气相色谱-质谱联用技术（GC-MS）研究昆虫表皮脂类的区域分布特征和组成差异; 2）利用蝗虫RNAi和果蝇遗传学揭示了编码参与脂质生物合成的关键酶的基因的功能（突变、RNAi和UAS-Gal 4表达系统）; 3）结合遗传学、组织化学染色、显微和超微结构技术分析角质层脂质分布和角质层脂质转运孔道形成的分子机制; 4）分析了关键基因在不同生态条件下影响昆虫生态适应性的机制。综上所述，通过这四种途径，我们将了解角质层脂质生物合成和运输的分子机制，了解角质层脂质的分布和组成如何共同影响昆虫的生态适应性。最终，我们的研究结果将有助于发现新的害虫防治目标和发展一个新的害虫防治策略对角质层脂质的形成和功能。

Insect cuticle lipids provide an effective two-sided barrier against dehydration and penetration of xenobiotics ensuring survival under potentially hostile environmental conditions such as high temperature and low humidity. Consequentially, they have a strong impact on insect ecological adaptability. However, research on molecular and genetic aspects of insect cuticle lipid biology is scarce to date. Ultimately, this negligence seriously restricts the development of green ecological control technologies based on cuticle lipids biology. In this proposal, we intend to use the agricultural pest Locusta migratoria (migratory locust) and the model insect Drosophila melanogaster (fruit fly) to undertake the following fundamental approaches: 1) studying the regional distribution characteristics and composition differences of insect cuticle lipids by using dye penetration assays and applying gas chromatography-mass spectrometry (GC-MS); 2) revealing the function of genes coding for key enzymes involved in lipid biosynthesis using locust RNAi and fly genetics (mutations, RNAi and UAS-Gal4 expression system); 3) combining genetics, histo-chemical staining, microscopic and ultra-structural technologies to analyze the molecular mechanisms of cuticle lipid distribution and the formation of cuticular lipid-transporting pore canals; 4) analyzing the mechanisms of how key genes affect insect ecological adaptability under different ecological conditions. In summary, through these four approaches, we will learn about the molecular mechanisms of cuticle lipid biosynthesis and transport, and understand how the distribution and composition of cuticle lipids together affect insect ecological adaptability. Eventually, our results will contribute to the discovery of new targets for pest control and to the development of a new pest control strategy against the formation and function of cuticle lipids.