Haemoglobin-mediated response to hyper-thermal stress in the keystone species Daphnia magna

Anthropogenic global warming has become a major geological and environmental force driving drastic changes in natural ecosystems. Due to the high thermal conductivity of water and the effects of temperature on metabolic processes, freshwater ecosystems are among the most impacted by these changes. The ability to tolerate changes in temperature may determine species long-term survival and fitness. Therefore, it is critical to identify coping mechanisms to thermal and hyper-thermal stress in aquatic organisms. A central regulatory element compensating for changes in oxygen supply and ambient temperature is the respiratory protein haemoglobin (Hb). Here, we quantify haemoglobin (Hb) plastic and evolutionary response in D. magna (sub)populations resurrected from the sedimentary archive of a lake with known history of increase in average temperature and recurrence of heat waves. By measuring constitutive changes in crude Hb protein content among (sub)populations we assessed evolution of the ...

人为全球变暖已成为驱动自然生态系统发生剧烈变化的重要地质与环境驱动力。由于水的高热传导性以及温度对代谢过程的影响，淡水生态系统是受此类变化影响最为显著的生态系统之一。物种耐受温度变化的能力，将决定其长期存活与进化适合度。因此，探明水生生物应对温度及高温胁迫的适应机制至关重要。作为补偿氧气供应与环境温度变化的核心调控因子，呼吸蛋白血红蛋白（haemoglobin，Hb）发挥着关键作用。本研究针对从某湖泊沉积物档案库中复活获得的大型溞（D. magna）亚种群，量化其血红蛋白的可塑性响应与进化响应；该湖泊存在平均气温上升、热浪频发的已知温度变化历史。通过测定各亚种群间粗血红蛋白蛋白含量的组成性变化，我们评估了...