Larval development, especially settlement and metamorphosis, has a vital influence on commercial culture during the life cycle of marine invertebrates. Sipunculus nudus, a peanut worm, is an important economic aquaculture species. However, information about the mechanism of its larval settlement and metamorphosis is still limited. Transcriptomic analysis was performed to determine the DEGs between the pelagospheric larva and creeping larva of S. nudus. A total of 96,455 unique unigenes were obtained and 46,355 were annotated. Transcriptome analysis revealed 19,352 DEGs, including 9,923 that were upregulated and 9,429 downregulated after settlement and metamorphosis. KEGG pathway enrichment analyses revealed that these DEGs were mainly involved in the Notch signaling pathway, TNF signaling pathway, protein digestion and absorption, thyroid hormone signaling pathway, and ECM–receptor interaction, and so on. Furthermore, the changes in genes related to cytoskeleton and cell adhesion indicated that protein degradation and apoptosis during metamorphosis mediate the loss of larval cilia and ECM remodeling functions in S. nudus metamorphosis. Changes in genes related to signal transduction and nervous system suggested the cessation of larval swimming, which is involved in settlement and metamorphosis. Changes in genes related to ingestion and digestion indicated that dietary shift occurred with metamorphic transition. Changes in some genes related to stress response and immunity indicated that conditioning induced the immune response of peanut worm. The results improve understanding of the physiological traits controlling S. nudus metamorphosis and provide a solid basis for further study.

幼体的发育，特别是沉降和变态，在海洋无脊椎动物的生命周期中对商业文化具有至关重要的影响。花生蠕虫Sipunculus nudus是重要的经济养殖品种。但是，有关其幼虫沉降和变态机制的信息仍然有限。进行了转录组学分析，确定了裸露葡萄球菌的pel盘幼虫和爬行幼虫之间的DEG 。。总共获得了96,455个独特的单基因，并注释了46,355个。转录组分析揭示了19,352个DEG，其中包括定居和变态后上调的9,923个DEG和下调的9,429个DEG。KEGG通路富集分析表明，这些DEG主要参与Notch信号通路，TNF信号通路，蛋白质消化吸收，甲状腺激素信号通路以及ECM-受体相互作用等。此外，与细胞骨架和细胞粘附有关的基因变化表明，变态过程中的蛋白质降解和细胞凋亡介导了S. nudus幼虫纤毛的丧失和ECM重塑功能。变态。与信号转导和神经系统有关的基因变化表明，幼体游泳停止了，这涉及定居和变态。与摄食和消化有关的基因变化表明，饮食转变发生了变态转变。一些与胁迫反应和免疫相关的基因的变化表明调理诱导了花生蠕虫的免疫反应。结果提高了对控制葡萄球菌变态的生理特性的了解，并为进一步研究提供了坚实的基础。