Güney Gözde, Cedden Doga, Scholten Stefan, Rostás Michael
Agricultural Entomology, Department of Crop Sciences, University of Göttingen, Göttingen, Germany.
Department of Evolutionary Developmental Genetics, Johann-Friedrich-Blumenbach Institute, GZMB, University of Göttingen, Göttingen, Germany.
Insect Biochem Mol Biol. 2025 May;180:104308. doi: 10.1016/j.ibmb.2025.104308. Epub 2025 Mar 31.
The cabbage stem flea beetle (Psylliodes chrysocephala, CSFB) is a significant pest of winter oilseed rape crops in northern Europe. CSFB adults aestivate during the summer to protect themselves from heat and desiccation stress. Trehalose, the primary hemolymph sugar, has been linked to energy homeostasis and stress resilience, but its regulation and function during aestivation remain poorly understood. Here, we investigated the roles of two trehalose transporters, Tret-1 and Tret-2, in modulating trehalose dynamics across different adult stages in CSFB. Through spatiotemporal transcript profiling, we found that Tret-1 was predominantly expressed in the fat body, where it facilitates trehalose export to the hemolymph, whereas Tret-2 expression was higher in the Malpighian tubules, mediating trehalose uptake from the hemolymph. RNA interference experiments revealed that Tret-1 is involved in transporting trehalose from the fat body into the hemolymph, while Tret-2 works reciprocally to transport trehalose from the hemolymph into the Malpighian tubules. The disruption of trehalose transportation resulted in excess glucose, glycogen, and triglyceride levels, mainly in pre-aestivation beetles. Furthermore, the knockdown of either trehalose transporter caused a compensatory increase in feeding activity in pre-aestivation beetles, while the knockdown of Tret-2 compromised resilience to heat stress. Our findings uncover the reciprocal functions of Tret-1 and Tret-2 in regulating trehalose distribution and maintaining metabolic stability during aestivation, offering insights into the physiological strategies underpinning insect survival during aestivation.
甘蓝茎跳甲（Psylliodes chrysocephala，CSFB）是北欧冬季油菜作物的一种重要害虫。CSFB成虫在夏季进行夏眠以保护自己免受高温和干燥胁迫。海藻糖是血淋巴中的主要糖类，与能量稳态和应激恢复力有关，但其在夏眠期间的调节和功能仍知之甚少。在这里，我们研究了两种海藻糖转运蛋白Tret-1和Tret-2在调节CSFB不同成虫阶段海藻糖动态中的作用。通过时空转录谱分析，我们发现Tret-1主要在脂肪体中表达，在那里它促进海藻糖输出到血淋巴中，而Tret-2在马氏管中的表达较高，介导从血淋巴中摄取海藻糖。RNA干扰实验表明，Tret-1参与将海藻糖从脂肪体转运到血淋巴中，而Tret-2则相反，将海藻糖从血淋巴转运到马氏管中。海藻糖运输的破坏导致葡萄糖、糖原和甘油三酯水平过高，主要出现在夏眠前的甲虫中。此外，敲低任何一种海藻糖转运蛋白都会导致夏眠前甲虫的取食活动代偿性增加，而敲低Tret-2会损害对热应激 的恢复力。我们的研究结果揭示了Tret-1和Tret-2在调节海藻糖分布和维持夏眠期间代谢稳定性方面的相互作用，为昆虫在夏眠期间生存的生理策略提供了见解。
