Department of Biology, Stanford University, Stanford, CA 94305, USA
Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA.
J Exp Biol. 2021 Feb 9;224(Pt 3):jeb230342. doi: 10.1242/jeb.230342.
Poison frogs sequester chemical defenses from their diet of leaf litter arthropods for defense against predation. Little is known about the physiological adaptations that confer this unusual bioaccumulation ability. We conducted an alkaloid-feeding experiment with the Diablito poison frog () to determine how quickly alkaloids are accumulated and how toxins modify frog physiology using quantitative proteomics. Diablito frogs rapidly accumulated the alkaloid decahydroquinoline within 4 days, and dietary alkaloid exposure altered protein abundance in the intestines, liver and skin. Many proteins that increased in abundance with decahydroquinoline accumulation are plasma glycoproteins, including the complement system and the toxin-binding protein saxiphilin. Other protein classes that change in abundance with decahydroquinoline accumulation are membrane proteins involved in small molecule transport and metabolism. Overall, this work shows that poison frogs can rapidly accumulate alkaloids, which alter carrier protein abundance, initiate an immune response, and alter small molecule transport and metabolism dynamics across tissues.
毒蛙从它们以落叶昆虫为食的饮食中分离出化学防御物质，以防御捕食者。目前对于赋予这种不寻常的生物积累能力的生理适应知之甚少。我们用 Diablito 毒蛙进行了生物碱喂养实验，以确定生物碱的积累速度以及毒素如何通过定量蛋白质组学改变青蛙的生理学。Diablito 青蛙在 4 天内迅速积累了 decahydroquinoline 生物碱，并且饮食生物碱暴露改变了肠道、肝脏和皮肤中的蛋白质丰度。随着 decahydroquinoline 积累而增加的许多丰富的蛋白质是血浆糖蛋白，包括补体系统和毒素结合蛋白 saxiphilin。随着 decahydroquinoline 积累而改变丰度的其他蛋白质类别是参与小分子运输和代谢的膜蛋白。总的来说，这项工作表明毒蛙可以快速积累生物碱，这些生物碱改变载体蛋白的丰度，引发免疫反应，并改变跨组织的小分子运输和代谢动力学。
