Developmental genetic studies of the embryonic development and metamorphosis of the pedipalp using the spider Parasteatoda tepidariorum (C. L. Koch, 1841)

蜘蛛须肢是一种多功能附肢，例如用于进食、感知和交配。因此，它在蜘蛛的适应和物种形成中起着重要作用。然而，须肢发育和变态的遗传学基础还不清楚。因此，发展机制的贡献pedipalp形态和功能的多样化和适应的演变目前不能被赞赏。因此，该项目的目的是确定所需的基因pedipalp形成在胚胎和pedipalp变态在胚胎后阶段的模式蜘蛛物种Parasteatoda tepidariorum，并确定它们在这些过程中的作用。该项目分为两个相辅相成的分项目。子项目1研究胚胎对须肢形态的贡献。它使用两种可用的RNA干扰（RNAi）介导的表型，导致胚胎须肢损失（唇-1 RNAi）和胚胎须肢复制（变形RNAi）。因此，唇-1 RNAi和畸形RNAi动物的胚胎转录组与野生型动物的胚胎转录组的差异基因表达分析将鉴定胚胎须肢形成所需的基因组。子项目2研究胚后发育对须肢形态的影响。一个特别的重点放在形成的灯泡装置，这是一个男性特定的结构，用于精子转移，并形成在一个变态过程中，最后蜕皮之前。分析雄性须肢组织在变态前、变态中和变态后的差异基因表达，并与年龄匹配的雌性的相同组织进行比较，将确定控制须肢变态和鳞茎器官大小和形状的基因组。这些基因的功能将通过RNAi进行测试，并设计了一种改良的胚后RNAi技术，仅影响足须的变态。在Parasteatoda tepidariorum中导致特别有趣的RNAi表型的基因也将在Parasteatoda lunata中分离和研究，Parasteatoda lunata是一种密切相关的蜘蛛物种，但是，在灯泡器官形态上不同，以提供比较的视角。

The spider pedipalp is a multifunctional appendage used e.g. for feeding, sensing and mating. It therefore has an important role in adaptation and speciation in spiders. The genetical basis of pedipalp development and metamorphosis, however, is not well understood. Thus, the contribution of developmental mechanisms to the evolution of pedipalp morphology and functional diversification and adaptation cannot currently be appreciated. The aim of the project is therefore to identify genes that are required for pedipalp formation in the embryo and pedipalp metamorphosis in the post-embryonic stages in the model spider species Parasteatoda tepidariorum, and to determine their role in these processes. The project is divided into two complementary subprojects. Subproject 1 investigates the embryonic contribution to pedipalp morphology. It uses two available RNA interference (RNAi) mediated phenotypes that lead to embryonic pedipalp loss (labial-1 RNAi) and embryonic pedipalp duplication (Deformed RNAi). Differential gene expression analysis of embryonic transcriptomes of labial-1 RNAi and Deformed RNAi animals with the embryonic transcriptome of wildtype animals will thus identify the gene set required for embryonic pedipalp formation. Subproject 2 investigates the postembryonic contribution to pedipalp morphology. A special focus is placed on the formation of the bulb apparatus, which is a male specific structure used for sperm transfer and that forms in a metamorphic process before the final molt. Analysis of differential gene expression in male pedipalp tissue before, during, and after metamorphosis, and the comparison with the same tissue of age-matched females will identify the gene set controlling pedipalp metamorphosis and bulb apparatus size and shape. The function of these genes will be tested via RNAi, and a modified technique for postembryonic RNAi has been devised to affect only the metamorphosis of the pedipalp. Genes resulting in an especially interesting RNAi phenotype in Parasteatoda tepidariorum will also be isolated and studied in Parasteatoda lunata, a closely related spider species that, however, differs in bulb apparatus morphology, to provide a comparative perspective.