Institute of Marine Biotechnology, Collaborative Innovation Center of Deep Sea Biology, School of Life Sciences, Tsinghua University , Beijing 100084, China.
Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University , Beijing 100084, China.
Environ Sci Technol. 2016 Feb 2;50(3):1157-65. doi: 10.1021/acs.est.5b05107. Epub 2016 Jan 13.
Interactive effects of ocean acidification and ocean warming on marine calcifiers vary among species, but little is known about the underlying mechanisms. The present study investigated the combined effects of seawater acidification and elevated temperature (ambient condition: pH 8.1 × 23 °C, stress conditions: pH 7.8 × 23 °C, pH 8.1 × 28 °C, and pH 7.8 × 28 °C, exposure time: two months) on the transcriptome and biomineralization of the pearl oyster Pinctada fucata, which is an important marine calcifier. Transcriptome analyses indicated that P. fucata implemented a compensatory acid-base mechanism, metabolic depression and positive physiological responses to mitigate the effects of seawater acidification alone. These responses were energy-expensive processes, leading to decreases in the net calcification rate, shell surface calcium and carbon content, and changes in the shell ultrastructure. Elevated temperature (28 °C) within the thermal window of P. fucata did not induce significant enrichment of the sequenced genes and conversely facilitated calcification, which was detected to alleviate the negative effects of seawater acidification on biomineralization and the shell ultrastructure. Overall, this study will help elucidate the mechanisms by which pearl oysters respond to changing seawater conditions and predict the effects of global climate change on pearl aquaculture.
海洋酸化和海水升温对海洋钙化生物的交互影响因物种而异，但其中的潜在机制却鲜为人知。本研究调查了海水酸化和升温（对照条件：pH8.1×23°C，胁迫条件：pH7.8×23°C、pH8.1×28°C、pH7.8×28°C，暴露时间：两个月）对珍珠贝（Pinctada fucata）转录组和生物矿化的综合影响，珍珠贝是一种重要的海洋钙化生物。转录组分析表明，珍珠贝实施了补偿性酸碱机制、代谢抑制和积极的生理反应，以减轻海水酸化的影响。这些反应是能源密集型的过程，导致净钙化率、壳表面钙和碳含量下降，以及壳超微结构的改变。在珍珠贝的热窗（28°C）内升高温度不会导致测序基因的显著富集，反而促进了钙化作用，这被检测到可以缓解海水酸化对生物矿化和壳超微结构的负面影响。总的来说，这项研究将有助于阐明珍珠贝对海水变化条件的反应机制，并预测全球气候变化对珍珠养殖的影响。
