Xu Elvis Genbo, Mager Edward M, Grosell Martin, Stieglitz John D, Hazard E Starr, Hardiman Gary, Schlenk Daniel
Department of Environmental Sciences, University of California, Riverside, California, United States of America.
Department of Biological Sciences, University of North Texas, Denton, Texas, United States of America.
PLoS One. 2017 Jul 10;12(7):e0180454. doi: 10.1371/journal.pone.0180454. eCollection 2017.
Mahi-mahi (Coryphaena hippurus) is a commercially and ecologically important species of fish occurring in tropical and temperate waters worldwide. Understanding early life events is crucial for predicting effects of environmental stress, which is largely restricted by a lack of genetic resources regarding expression of early developmental genes and regulation of pathways. The need for anchoring developmental stages to transcriptional activities is highlighted by increasing evidence on the impacts of recurrent worldwide oil spills in this sensitive species during early development. By means of high throughput sequencing, we characterized the developmental transcriptome of mahi-mahi at three critical developmental stages, from pharyngula embryonic stage (24 hpf) to 48 hpf yolk-sac larva (transition 1), and to 96 hpf free-swimming larva (transition 2). With comparative analysis by multiple bioinformatic tools, a larger number of significantly altered genes and more diverse gene ontology terms were observed during transition 2 than transition 1. Cellular and tissue development terms were more significantly enriched in transition 1, while metabolism related terms were more enriched in transition 2, indicating a switch progressing from general embryonic development to metabolism during the two transitions. Special focus was given on the most significant common canonical pathways (e.g. calcium signaling, glutamate receptor signaling, cAMP response element-binding protein signaling, cardiac β-adrenergic signaling, etc.) and expression of developmental genes (e.g. collagens, myosin, notch, glutamate metabotropic receptor etc.), which were associated with morphological changes of nervous, muscular, and cardiovascular system. These data will provide an important basis for understanding embryonic development and identifying molecular mechanisms of abnormal development in fish species.
鲯鳅（Coryphaena hippurus）是一种在全球热带和温带水域具有商业和生态重要性的鱼类。了解早期生命事件对于预测环境压力的影响至关重要，而这在很大程度上受到早期发育基因表达和途径调控方面遗传资源匮乏的限制。全球范围内反复发生的石油泄漏对这种敏感物种早期发育的影响的证据不断增加，凸显了将发育阶段与转录活动相锚定的必要性。通过高通量测序，我们对鲯鳅在三个关键发育阶段的转录组进行了表征，从咽胚期胚胎阶段（24小时胚胎发育阶段）到48小时卵黄囊幼虫阶段（转变1），再到96小时自由游动幼虫阶段（转变2）。通过多种生物信息学工具进行比较分析，发现转变2期间观察到的显著改变的基因数量更多，基因本体术语也更多样化。细胞和组织发育术语在转变1中富集更为显著，而与代谢相关的术语在转变2中富集更为明显，这表明在这两个转变过程中从一般胚胎发育向代谢的转变正在进行。特别关注了最显著的常见经典途径（如钙信号传导、谷氨酸受体信号传导、cAMP反应元件结合蛋白信号传导、心脏β - 肾上腺素能信号传导等）以及发育基因（如胶原蛋白、肌球蛋白、Notch、代谢型谷氨酸受体等）的表达，这些与神经、肌肉和心血管系统的形态变化相关。这些数据将为理解鱼类胚胎发育和识别异常发育的分子机制提供重要依据。
