Abstract：
The mechanisms underlying the toxicity of environmental stress are unclear for marine macrobenthos. Copper/Cu has posed the most serious threats to amphioxus, an ancient and model benthic cephalochordate. Herein, a dynamic change in the physiological parameters (GR, SOD, ATP, and MDA) was detected with ROS accumulation in Branchiostoma belcheri exposed to 0.3 mg·L-1 Cu. Transcriptomes and microRNAomes of B. belcheri were generated to investigate the molecular mechanisms by which this amphioxus copes with Cu exposure. Time-specific genes identified at different time points after exposure were involved in the stimulus and immune response, detoxification and ionic homeostasis, aging and the nervous system, sequentially, with prolongation of exposure time, forming a dynamic process of molecular response to Cu stress. In total, 57 differentially expressed miRNAs were identified under Cu stress. Transcriptomics-miRNAomics analyses indicate that these miRNAs targeted genes associated with many key biological processes such as xenobiotics degradation, oxidative stress, and energy metabolism. The constructed miRNA-mRNA-pathway network uncovered a broad post-transcriptional regulatory mechanism in B. belcheri to cope with Cu stress. Overall, this integrated analyses show that enhanced defense response, accelerated ROS elimination, and repressed ATP production constitute a comprehensive strategy to cope with Cu toxicity in the ancient macrobenthos.
摘要：
海洋大型底栖动物的环境胁迫毒性机制尚不清楚。铜/铜对文昌鱼构成了最严重的威胁，一种古老的和模型的底栖头索动物。在这里，生理参数的动态变化(GR，SOD,ATP,和MDA）通过暴露于0.3mg·L-1Cu的Branchiostomabelcheri中的ROS积累来检测。产生了B.belcheri的转录组和微RNAome，以研究这种文昌鱼应对Cu暴露的分子机制。在暴露后不同时间点鉴定的时间特异性基因参与刺激和免疫反应，解毒和离子稳态，衰老和神经系统，顺序，随着暴露时间的延长，形成分子对Cu应力响应的动态过程。总的来说,在Cu胁迫下鉴定了57个差异表达的miRNA。转录组学-miRNA组学分析表明，这些miRNA靶向与许多关键生物过程相关的基因，例如异源生物降解，氧化应激，和能量代谢。构建的miRNA-mRNA通路网络揭示了B.belcheri应对Cu胁迫的广泛转录后调控机制。总的来说,这种综合分析表明，增强的防御反应，加速ROS消除，和抑制的ATP生产构成了应对古代大型底栖动物中Cu毒性的综合策略。
