蜕皮类固醇,作为关键的生长激素,调节换羽,节肢动物的变态和繁殖。Ecdysterid生物合成由一系列由万圣节基因编码的细胞色素P450单加氧酶(CYP450)催化,包括spook(spo),幻影(PHM),无形(dib),阴影(悲伤)和阴影(shd)。以20-羟基蜕皮激素(20E)为主要的蜕皮激素,昆虫中的蜕皮激素生物合成很清楚。然而,关于蛛形纲动物中主要的蜕皮类固醇的信息是有限的。在这项研究中,万圣节基因spo,dib,悲伤和shd,但不是PHM,在池塘狼蜘蛛中被发现,假环帕。系统发育分析将蜘蛛和昆虫万圣节基因产物分为两个CYP450进化枝,CYP2家族(spo和phm)和线粒体家族(dib,悲伤,和shd)。在假环状假单胞菌中,四个万圣节基因的时间表达谱与蜘蛛的蜕皮同时发生,在第二龄幼虫的过程中稳步增加,然后在蜕皮完成后迅速下降。空间上,这四个万圣节基因在成年女性的蜘蛛腹部和卵巢中高度表达。并行,ponasteroneA(PA),但不是20E,通过LC-MS/MS分析在假眼假单胞菌中检测到,通过添加PA加速蜕皮,它被证明是蜘蛛中的功能性蜕皮类固醇。本研究揭示了蜘蛛和昆虫中不同的蜕皮类固醇生物合成途径。
Ecdysteroids, as the key growth hormones, regulate moulting, metamorphosis and reproduction in arthropods. Ecdysteroid biosynthesis is catalysed by a series of cytochrome P450 monooxygenases (CYP450s) encoded by Halloween genes, including spook (spo), phantom (phm), disembodied (dib), shadow (sad) and shade (shd). The ecdysteroid biosynthesis in insects is clear with 20-hydroxyecdysone (20E) as the main ecdysteroid. However, the information on the major ecdysteroids in arachnids is limited. In this study, Halloween genes spo, dib, sad and shd, but not phm, were identified in the pond wolf spider, Pardosa pseudoannulata. Phylogenetic analysis grouped arachnid and insect Halloween gene products into two CYP450 clades, the CYP2 clan (spo and phm) and the mitochondrial clan (dib, sad, and shd). In P. pseudoannulata, the temporal expression profile of the four Halloween genes in concurrence with spiderling moulting with steady increase in the course of the 2nd instar followed by a rapid dropdown once moulting was completed. Spatially, the four Halloween genes were highly expressed in spiderling abdomen and in the ovaries of female adults. In parallel, ponasterone A (PA), but not 20E, was detected by LC-MS/MS analysis in P. pseudoannulata, and it was demonstrated as a functional ecdysteroid in the spider by accelerating of moulting with PA addition. The present study revealed the different ecdysteroid biosynthesis pathways in spiders and insects.