PDF(Pubmed)
Abstract：
Marine ecosystems are facing escalating environmental fluctuations owing to climate change and human activities, imposing pressures on marine species. To withstand recurring environmental challenges, marine organisms, especially benthic species lacking behavioral choices to select optimal habitats, have to utilize well-established strategies such as the antioxidant defense system (ADS) to ensure their survival. Therefore, understanding of the mechanisms governing the ADS-based response is essential for gaining insights into adaptive strategies for managing environmental challenges. Here we conducted a comparative analysis of the physiological and transcriptional responses based on the ADS during two rounds of \'hypersalinity-recovery\' challenges in two model congeneric invasive ascidians, Ciona robusta and C. savignyi. Our results demonstrated that C. savignyi exhibited higher tolerance and resistance to salinity stresses at the physiological level, while C. robusta demonstrated heightened responses at the transcriptional level. We observed distinct transcriptional responses, particularly in the utilization of two superoxide dismutase (SOD) isoforms. Both Ciona species developed physiological stress memory with elevated total SOD (T-SOD) and glutathione (GSH) responses, while only C. robusta demonstrated transcriptional stress memory. The regulatory distinctions within the Nrf2-Keap1 signalling pathway likely explain the formation disparity of transcriptional stress memory between both Ciona species. These findings support the \'context-dependent stress memory hypothesis\', emphasizing the emergence of species-specific stress memory at diverse regulatory levels in response to recurrent environmental challenges. Our results enhance our understanding of the mechanisms of environmental challenge management in marine species, particularly those related to the ADS.
UNASSIGNED: The online version contains supplementary material available at 10.1007/s42995-024-00228-y.
UNASSIGNED: The online version contains supplementary material available at 10.1007/s42995-024-00228-y.
摘要：
由于气候变化和人类活动，海洋生态系统面临着不断升级的环境波动，对海洋物种施加压力。为了应对反复出现的环境挑战，海洋生物,特别是底栖物种缺乏选择最佳栖息地的行为选择，必须利用成熟的策略，如抗氧化剂防御系统（ADS），以确保他们的生存。因此,了解基于ADS的响应机制对于了解管理环境挑战的适应性策略至关重要。在这里，我们对基于ADS的生理和转录反应进行了比较分析，在两个模型同属侵袭性海鞘中进行了两轮“高盐度恢复”挑战，西奥娜·罗布斯塔和萨维尼。我们的结果表明C.savignyi在生理水平上表现出更高的对盐度胁迫的耐受性和抗性，而C.robusta在转录水平上表现出增强的反应。我们观察到不同的转录反应，特别是在利用两种超氧化物歧化酶（SOD）亚型时。Ciona物种都发展了生理应激记忆，总SOD（T-SOD）和谷胱甘肽（GSH）反应升高，而只有罗布斯塔表现出转录应激记忆。Nrf2-Keap1信号通路内的调节差异可能解释了两种Ciona物种之间转录应激记忆的形成差异。这些发现支持“上下文相关的压力记忆假设”，强调物种特异性应激记忆的出现在不同的监管水平，以应对反复出现的环境挑战。我们的结果增强了我们对海洋物种环境挑战管理机制的理解，特别是那些与广告有关的。
■在线版本包含补充材料，可在10.1007/s42995-024-00228-y获得。
■在线版本包含补充材料，可在10.1007/s42995-024-00228-y获得。
