Institut de Génomique Fonctionnelle de Lyon, Université de Lyon, Université Claude Bernard Lyon 1, UMR CNRS 5242, Ecole Normale Supérieure de Lyon, Lyon, France.
CRIOBE USR3278 EPHE-UPVD-CNRS, PSL Research University, Moorea, French Polynesia.
Elife. 2017 Oct 30;6:e27595. doi: 10.7554/eLife.27595.
Larval recruitment, the transition of pelagic larvae into reef-associated juveniles, is a critical step for the resilience of marine fish populations but its molecular control is unknown. Here, we investigate whether thyroid-hormones (TH) and their receptors (TR) coordinate the larval recruitment of the coral-reef-fish . We demonstrate an increase of TH-levels and -expressions in pelagic-larvae, followed by a decrease in recruiting juveniles. We generalize these observations in four other coral reef-fish species. Treatments with TH or TR-antagonist, as well as relocation to the open-ocean, disturb larvae transformation and grazing activity. Likewise, chlorpyrifos, a pesticide often encountered in coral-reefs, impairs TH-levels, transformation, and grazing activity, hence diminishing this herbivore's ability to control the spread of reef-algae. Larval recruitment therefore corresponds to a TH-controlled metamorphosis, sensitive to endocrine disruption. This provides a framework to understand how larval recruitment, critical to reef-ecosystems maintenance, is altered by anthropogenic stressors.
幼虫补充，即浮游幼虫转变为与珊瑚礁相关的幼鱼，是海洋鱼类种群恢复力的关键步骤，但它的分子控制尚不清楚。在这里，我们研究了甲状腺激素（TH）及其受体（TR）是否协调珊瑚礁鱼类的幼虫补充。我们证明了浮游幼虫中 TH 水平和表达的增加，随后是招募的幼鱼减少。我们在另外四种珊瑚礁鱼类中推广了这些观察结果。用 TH 或 TR 拮抗剂处理，以及迁移到开阔海域，都会干扰幼虫的转化和摄食活动。同样，在珊瑚礁中经常遇到的杀虫剂毒死蜱会损害 TH 水平、转化和摄食活动，从而降低这种食草动物控制珊瑚礁藻类扩散的能力。因此，幼虫补充对应于受内分泌干扰影响的 TH 控制的变态。这为理解幼虫补充如何被人为压力改变提供了一个框架，幼虫补充对于珊瑚礁生态系统的维持至关重要。
