Sandlund Liv, Nilsen Frank, Male Rune, Dalvin Sussie
Sea Lice Research Centre, Department of Biology, University of Bergen, Norway.
Sea Lice Research Centre, Department of Biology, University of Bergen, Norway.
Mol Biochem Parasitol. 2016 Aug;208(2):65-73. doi: 10.1016/j.molbiopara.2016.06.007. Epub 2016 Jun 21.
The function of the ecdysone receptor (EcR) during development and molting has been thoroughly investigated in some arthropods such as insects but rarely in crustacean copepods such as the salmon louse Lepeophtheirus salmonis (L. salmonis) (Copepoda, Caligidae). The salmon louse is an ectoparasite on Atlantic salmon that has major economical impact in aquaculture due to the cost of medical treatment methods to remove lice from the fish. Handling of salmon louse infestations is further complicated by development of resistance towards available medicines. Understanding of basic molecular biological processes in the salmon louse is essential to enable development of new tools to control the parasite. In this study, we found L. salmonis EcR (LsEcR) transcript to be present in the neuronal somata of the brain, nuclei of muscle fibres and the immature intestine of the salmon louse. Furthermore, we explored the function of LsEcR during development using RNA interference mediated knock-down and through infection trials. Our results show that knock-down of LsEcR in the salmon louse is associated with hypotrophy of several tissues, delayed development and mortality. In addition, combined knock-down of LsEcR/LsRXR resulted in molting arrest during early larval stages.
蜕皮激素受体（EcR）在发育和蜕皮过程中的功能已在一些节肢动物（如昆虫）中得到了深入研究，但在甲壳纲桡足类动物（如鲑鱼虱Lepeophtheirus salmonis，简称L. salmonis）中却鲜有研究。鲑鱼虱是大西洋鲑鱼身上的一种体外寄生虫，由于需要花费治疗成本来清除鱼身上的虱子，它对水产养殖造成了重大经济影响。对现有药物产生的抗药性进一步加剧了鲑鱼虱感染的处理难度。了解鲑鱼虱的基本分子生物学过程对于开发控制这种寄生虫的新工具至关重要。在本研究中，我们发现鲑鱼虱EcR（LsEcR）转录本存在于鲑鱼虱大脑的神经细胞体、肌纤维细胞核和未成熟的肠道中。此外，我们通过RNA干扰介导的敲低和感染试验，探索了LsEcR在发育过程中的功能。我们的结果表明，鲑鱼虱中LsEcR的敲低与多个组织的萎缩、发育延迟和死亡有关。此外，LsEcR/LsRXR的联合敲低导致幼虫早期阶段的蜕皮停滞。
