Haemoglobin-mediated response to hyper-thermal stress in the keystone species Daphnia magna.
Haemoglobin-mediated response to hyper-thermal stress in the keystone species Daphnia magna.
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DOI：
10.1111/eva.12561
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发表时间：
2018-01
影响因子：
4.1
通讯作者：
Orsini L
中科院分区：
文献类型：
--
作者：
Cuenca Cambronero M;Zeis B;Orsini L
人类活动造成的全球变暖已成为推动自然生态系统剧烈变化的主要地质和环境力量。由于水的高导热性和温度对代谢过程的影响，淡水生态系统是受这些变化影响最严重的生态系统之一。耐受温度变化的能力可能决定物种的长期生存和适应度。因此，确定水生生物对热和超高温胁迫的应对机制至关重要。补偿氧气供应和环境温度变化的中心调节元件是呼吸蛋白血红蛋白（Hb）。在这里，我们量化血红蛋白塑料和大型蚤亚群复活的沉积档案的湖泊与已知的历史增加平均温度和热浪复发的进化反应。通过测量亚群之间的粗Hb蛋白质含量的组成变化，我们评估了Hb基因家族对温度升高的反应。为了量化该基因家族对高温应激反应的可塑性贡献，我们量化了与非应激温度相比，高温应激下所有亚群中Hb含量的变化。此外，我们测试了竞争能力的基因型作为其Hb含量的函数，组成和诱导。我们发现，在高温胁迫下，经过一段时间的驯化后，与Hb贫乏的基因型相比，Hb丰富的基因型具有上级竞争能力。这些发现表明，虽然长期适应热浪发生率较高可能需要可塑性和遗传适应的结合，但可塑性最有可能是短期内应对高温压力的机制。我们的研究表明，随着热浪发生率的增加，富含Hb的基因型可能对群体遗传多样性产生潜在的长期影响。
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 Hb plastic and evolutionary response in Daphnia magna subpopulations 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 subpopulations, we assessed evolution of the Hb gene family in response to temperature increase. To quantify the contribution of plasticity in the response of this gene family to hyper‐thermal stress, we quantified changes in Hb content in all subpopulations under hyper‐thermal stress as compared to nonstressful temperature. Further, we tested competitive abilities of genotypes as a function of their Hb content, constitutive and induced. We found that Hb‐rich genotypes have superior competitive abilities as compared to Hb‐poor genotypes under hyper‐thermal stress after a period of acclimation. These findings suggest that whereas long‐term adjustment to higher occurrence of heat waves may require a combination of plasticity and genetic adaptation, plasticity is most likely the coping mechanism to hyper‐thermal stress in the short term. Our study suggests that with higher occurrence of heat waves, Hb‐rich genotypes may be favoured with potential long‐term impact on population genetic diversity.
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影响因子：
2.1
作者：
Livingstone, DM;Lotter, AF
通讯作者：
Lotter, AF
影响因子：
30.8
作者：
Campbell, Kevin L.;Roberts, Jason E. E.;Cooper, Alan
通讯作者：
Cooper, Alan
影响因子：
4.8
作者：
Gorr, TA;Cahn, JD;Bunn, HF
通讯作者：
Bunn, HF
影响因子：
2.6
作者：
BERG, S;JEPPESEN, E;MORTENSEN, E
通讯作者：
MORTENSEN, E
影响因子：
12.8
作者：
ELENDT, BP;BIAS, WR
通讯作者：
BIAS, WR