蜕皮激素受体在双翅目和鳞翅目中的快速分化表明ECR和USP-RXR之间存在协同进化
Rapid divergence of the ecdysone receptor in Diptera and Lepidoptera suggests coevolution between ECR and USP-RXR
摘要：
蜕皮激素是昆虫生殖和发育的主要调节因子，包括幼虫蜕皮和变态。功能性蜕皮激素受体是ECR（NR 1H 1）和USP-RXR（NR 2B 4）的异源二聚体，其是脊椎动物类维生素A X受体（RXR α、β、γ）的直向同源物。这两种蛋白都属于核激素受体超家族，配体依赖性转录因子，共有两个保守结构域：DNA结合结构域（DBD）和配体结合结构域（LBD）。为了进一步了解变态的进化和蜕皮激素的基因调控在节肢动物中，我们进行了系统发育分析的异二聚体ECR/USP-RXR的两个合作伙伴。总体而言，来自33个物种的38个USP-RXR和19个ECR蛋白质序列已用于本分析。有趣的是，序列比对和结构比较揭示了ECR和USP-RXR的高分歧率，特别是在双翅目和鳞翅目之间。最令人印象深刻的差异影响USP-RXR的配体结合结构域。此外，ECR序列在其他结构域，即DNA结合和羧基末端F结构域中显示出变异性。我们的数据提供了第一个证据表明，ECR和USP-RXR可能在全变态昆虫多样化过程中共同进化，导致蜕皮激素受体的功能分歧。这些结果对昆虫发育、核受体的进化和特定杀虫剂的设计等基本方面具有普遍意义。
英文摘要：
Ecdysteroid hormones are major regulators in reproduction and development of insects, including larval molts and metamorphosis. The functional ecdysone receptor is a heterodimer of ECR (NR1H1) and USP-RXR (NR2B4), which is the orthologue of vertebrate retinoid X receptors (RXR alpha, beta, gamma). Both proteins belong to the superfamily of nuclear hormone receptors, ligand-dependent transcription factors that share two conserved domains: the DNA-binding domain (DBD) and the ligand-binding domain (LBD). In order to gain further insight into the evolution of metamorphosis and gene regulation by ecdysone in arthropods, we performed a phylogenetic analysis of both partners of the heterodimer ECR/USP-RXR. Overall, 38 USP-RXR and 19 ECR protein sequences, from 33 species, have been used for this analysis. Interestingly, sequence alignments and structural comparisons reveal high divergence rates, for both ECR and USP-RXR, specifically among Diptera and Lepidoptera. The most impressive differences affect the ligand-binding domain of USP-RXR. In addition, ECR sequences show variability in other domains, namely the DNA-binding and the carboxy-terminal F domains. Our data provide the first evidence that ECR and USP-RXR may have coevolved during holometabolous insect diversification, leading to a functional divergence of the ecdysone receptor. These results have general implications on fundamental aspects of insect development, evolution of nuclear receptors, and the design of specific insecticides.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
