Kaczmarek Agata, Boguś Mieczysława Irena
Witold Stefański Institute of Parasitology, Polish Academy of Sciences, Twarda 51/55, 00-818 Warsaw, Poland.
BIOMIBO, Strzygłowska 15, 04-872 Warsaw, Poland.
Insects. 2021 Oct 27;12(11):970. doi: 10.3390/insects12110970.
The chemical composition of the insect cuticle varies remarkably between species and their life stages. It can affect host resistance and substrate utilization by invading entomopathogen fungi, such as the soil fungus . In this study, flies were exposed to sporulating colonies for 24 h; the pupae were resistant, but the adults demonstrated 60% mortality. Although the pupae demonstrated no sign of infection nor any abnormal development, our findings indicate that after 24 h of contact with the fungus, the pupae demonstrated a 25.2-fold increase in total cuticular free fatty acids (FFAs) and a 1.9-fold decrease in total internal FFAs. Also, the cuticular FFA increased from 26 to 30, while the internal FFA class increased from 13 to 23. In exposed adults, the total mass of cuticular FFAs increased 1.7-fold, while the number of FFAs stayed the same (32 FFAs). Also, the internal FFA class increased from 26 to 35 and the total FFA mass increased 1.1-fold. These considerable differences between adults and pupae associated with exposure indicate developmental changes in the mechanisms governing lipid metabolism and spatial distribution in the organism, and suggest that cuticular lipids play a vital role in the defence against pathogenic fungi.
昆虫表皮的化学成分在不同物种及其生命阶段之间存在显著差异。它会影响宿主抗性以及入侵昆虫病原真菌（如土壤真菌）对底物的利用。在本研究中，将苍蝇暴露于产孢菌落24小时；蛹具有抗性，但成虫的死亡率为60%。尽管蛹没有感染迹象也没有任何异常发育，但我们的研究结果表明，与真菌接触24小时后，蛹的表皮游离脂肪酸（FFA）总量增加了25.2倍，内部FFA总量减少了1.9倍。此外，表皮FFA种类从26种增加到30种，而内部FFA种类从13种增加到23种。在暴露的成虫中，表皮FFA的总质量增加了1.7倍，而FFA的数量保持不变（32种FFA）。此外，内部FFA种类从26种增加到35种，FFA总质量增加了1.1倍。成虫和蛹在暴露后的这些显著差异表明，生物体中控制脂质代谢和空间分布的机制存在发育变化，并表明表皮脂质在抵御病原真菌方面起着至关重要的作用。
