Moore Billy, Jolly Jeffrey, Izumiyama Michael, Kawai Erina, Ryu Taewoo, Ravasi Timothy
Marine Climate Change Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan.
Marine Climate Change Unit, Okinawa Institute of Science and Technology Graduate University, 1919-1 Tancha, Onna-son, Okinawa 904-0495, Japan.
Sci Total Environ. 2023 May 15;873:162296. doi: 10.1016/j.scitotenv.2023.162296. Epub 2023 Feb 17.
Increasing ocean temperatures have been demonstrated to have a range of negative impacts on coral reef fishes. However, despite a wealth of studies of juvenile/adult reef fish, studies of how early developmental stages respond to ocean warming are limited. As overall population persistence is influenced by the development of early life stages, detailed studies of larval responses to ocean warming are essential. Here, in an aquaria-based study we investigate how temperatures associated with future warming and present-day marine heatwaves (+3 °C) impact the growth, metabolic rate, and transcriptome of 6 discrete developmental stages of clownfish larvae (Amphiprion ocellaris). A total of 6 clutches of larvae were assessed, with 897 larvae imaged, 262 larvae undergoing metabolic testing and 108 larvae subject to transcriptome sequencing. Our results show that larvae reared at +3 °C grow and develop significantly faster and exhibit higher metabolic rates than those in control conditions. Finally, we highlight the molecular mechanisms underpinning the response of larvae from different developmental stages to higher temperatures, with genes associated with metabolism, neurotransmission, heat stress and epigenetic reprogramming differentially expressed at +3 °C. Overall, these results indicate that clownfish development could be altered under future warming, with developmental rate, metabolic rate, and gene expression all affected. Such changes may lead to altered larval dispersal, changes in settlement time and increased energetic costs.
海洋温度上升已被证明会对珊瑚礁鱼类产生一系列负面影响。然而，尽管对幼年/成年礁鱼进行了大量研究，但关于早期发育阶段如何应对海洋变暖的研究却很有限。由于总体种群的持续性受到早期生命阶段发育的影响，因此详细研究幼体对海洋变暖的反应至关重要。在此，在一项基于水族箱的研究中，我们调查了与未来变暖以及当前海洋热浪（+3°C）相关的温度如何影响小丑鱼幼体（眼斑双锯鱼）6个离散发育阶段的生长、代谢率和转录组。总共评估了6窝幼体，对897只幼体进行了成像，262只幼体进行了代谢测试，108只幼体进行了转录组测序。我们的结果表明，在+3°C条件下饲养的幼体生长发育明显更快，并且比对照条件下的幼体表现出更高的代谢率。最后，我们强调了不同发育阶段的幼体对较高温度反应的分子机制，与代谢、神经传递、热应激和表观遗传重编程相关的基因在+3°C时差异表达。总体而言，这些结果表明，在未来变暖的情况下，小丑鱼的发育可能会发生改变，发育速率、代谢率和基因表达都会受到影响。这种变化可能会导致幼体扩散改变、定居时间变化以及能量成本增加。
