Abstract：
Ecdysteroid molting hormones coordinate arthropod growth and development. Binding of 20-hydroxyecdysone (20E) to ecdysteroid receptor EcR/RXR activates a cascade of nuclear receptor transcription factors that mediate tissue responses to hormone. Insect ecdysteroid responsive and Forkhead box class O (FOXO) transcription factor gene sequences were used to extract orthologs from blackback land crab (Gecarcinus lateralis) Y-organ (YO) transcriptome: Gl-Ecdysone Receptor (EcR), Gl-Broad Complex (Br-C), Gl-E74, Gl-Hormone Receptor 3 (HR3), Gl-Hormone Receptor 4 (HR4), Gl-FOXO, and Gl-Fushi tarazu factor-1 (Ftz-f1). Quantitative polymerase chain reaction quantified mRNA levels in tissues from intermolt animals and in YO of animals induced to molt by multiple limb autotomy (MLA) or eyestalk ablation (ESA). Gl-EcR, Gl-Retinoid X Receptor (RXR), Gl-Br-C, Gl-HR3, Gl-HR4, Gl-E74, Gl-E75, Gl-Ftz-f1, and Gl-FOXO were expressed in all 10 tissues, with Gl-Br-C, Gl-E74, Gl-E75, and Gl-HR4 mRNA levels in the YO lower than those in most of the other tissues. In MLA animals, molting had no effect on Gl-Br-C, Gl-E74, and Gl-Ftz-f1 mRNA levels and little effect on Gl-EcR, Gl-E75, and Gl-HR4 mRNA levels. Gl-HR3 and Gl-FOXO mRNA levels were increased during premolt stages, while Gl-RXR mRNA level was highest during intermolt and premolt stages and lowest at postmolt stage. In ESA animals, YO mRNA levels were not correlated with hemolymph ecdysteroid titers. ESA had no effect on Gl-EcR, Gl-E74, Gl-HR3, Gl-HR4, Gl-Ftz-f1, and Gl-FOXO mRNA levels, while Gl-RXR, Gl-Br-C, and Gl-E75 mRNA levels were decreased at 3 days post-ESA. These data suggest that transcriptional up-regulation of Gl-FOXO and Gl-HR3 contributes to increased YO ecdysteroidogenesis during premolt. By contrast, transcriptional regulation of ecdysteroid responsive genes and ecdysteroidogenesis were uncoupled in the YO of ESA animals.
摘要：
节肢动物蜕皮激素协调生长和发育。20-羟基蜕皮激素（20E）与蜕皮类固醇受体EcR/RXR的结合激活了介导组织对激素反应的核受体转录因子的级联反应。昆虫蜕皮类固醇反应性和叉头盒O类（FOXO）转录因子基因序列用于从黑背陆蟹（Gecarcinuslateralis）Y器官（YO）转录组提取直向同源物：Gl-蜕皮激素受体（EcR），Gl-广义络合物(Br-C),Gl-E74,Gl-激素受体3(HR3),Gl-激素受体4(HR4),Gl-FOXO,和Gl-Fushitarazu因子-1(Ftz-f1)。定量聚合酶链反应定量了蜕皮动物组织中的mRNA水平以及通过多次肢体自动切开术（MLA）或眼柄消融（ESA）诱导蜕皮的动物YO中的mRNA水平。Gl-EcR,Gl-视黄醇X受体(RXR),Gl-Br-C,Gl-HR3、Gl-HR4、Gl-E74、Gl-E75、Gl-Ftz-f1和Gl-FOXO在全部10个组织中均有表达,用Gl-Br-C，YO中的Gl-E74、Gl-E75和Gl-HR4mRNA水平低于大多数其他组织中的水平。在MLA动物中，蜕皮对Gl-Br-C没有影响，Gl-E74和Gl-Ftz-f1mRNA水平对Gl-EcR影响不大,Gl-E75和Gl-HR4mRNA水平。Gl-HR3和Gl-FOXOmRNA水平在蜕皮前期增加，而Gl-RXRmRNA水平在蜕皮和蜕皮前期最高，在蜕皮后阶段最低。在欧空局的动物中，YOmRNA水平与血淋巴蜕皮类固醇滴度无关。欧空局对Gl-EcR没有影响,Gl-E74、Gl-HR3、Gl-HR4、Gl-Ftz-f1和Gl-FOXOmRNA水平，而Gl-RXR,Gl-Br-C,和Gl-E75mRNA水平在ESA后3天降低。这些数据表明Gl-FOXO和Gl-HR3的转录上调有助于在预蜕皮期间增加的YO蜕皮激素生成。相比之下,在ESA动物的YO中，蜕皮类固醇反应基因和蜕皮类固醇发生的转录调控是分离的。
