Simčič Tatjana, Pajk Franja, Jaklič Martina, Brancelj Anton, Vrezec Al
Department of Freshwater and Terrestrial Ecosystems Research, National Institute of Biology, Večna pot 111, SI-1000 Ljubljana, Slovenia.
Department of Freshwater and Terrestrial Ecosystems Research, National Institute of Biology, Večna pot 111, SI-1000 Ljubljana, Slovenia.
J Therm Biol. 2014 Apr;41:21-30. doi: 10.1016/j.jtherbio.2013.06.003. Epub 2013 Jul 6.
Whether electron transport system (ETS) activity could be used as an estimator of crayfish thermal tolerance has been investigated experimentally. Food consumption rate, respiration rates in the air and water, the difference between energy consumption and respiration costs at a given temperature ('potential growth scope', PGS), and ETS activity of Orconectes limosus and Pacifastacus leniusculus were determined over a temperature range of 5-30°C. All concerned parameters were found to be temperature dependent. The significant correlation between ETS activity and PGS indicates that they respond similarly to temperature change. The regression analysis of ETS activity as an estimator of thermal tolerance at the mitochondrial level and PGS as an indicator of thermal tolerance at the organismic level showed the shift of optimum temperature ranges of ETS activity to the right for 2° in O. limosus and for 3° in P. leniusculus. Thus, lower estimated temperature optima and temperatures of optimum ranges of PGS compared to ETS activity could indicate higher thermal sensitivity at the organismic level than at a lower level of complexity (i.e. at the mitochondrial level). The response of ETS activity to temperature change, especially at lower and higher temperatures, indicates differences in the characteristics of the ETSs in O. limosus and P. leniusculus. O. limosus is less sensitive to high temperature. The significant correlation between PGS and ETS activity supports our assumption that ETS activity could be used for the rapid estimation of thermal tolerance in crayfish species.
电子传递系统（ETS）活性是否可作为小龙虾热耐受性的估计指标已通过实验进行了研究。在5-30°C的温度范围内，测定了光滑沼虾和美洲螯龙虾的食物消耗率、在空气和水中的呼吸率、给定温度下能量消耗与呼吸成本之间的差异（“潜在生长范围”，PGS）以及ETS活性。发现所有相关参数均与温度有关。ETS活性与PGS之间的显著相关性表明它们对温度变化的反应相似。将ETS活性作为线粒体水平热耐受性的估计指标，以及将PGS作为机体水平热耐受性的指标进行回归分析，结果显示光滑沼虾的ETS活性最适温度范围向右移动了2°，美洲螯龙虾则向右移动了3°。因此，与ETS活性相比，PGS的估计最适温度和最适温度范围较低，这可能表明机体水平的热敏感性高于较低复杂程度水平（即线粒体水平）。ETS活性对温度变化的反应，尤其是在较低和较高温度下，表明光滑沼虾和美洲螯龙虾的ETS特性存在差异。光滑沼虾对高温不太敏感。PGS与ETS活性之间的显著相关性支持了我们的假设，即ETS活性可用于快速估计小龙虾物种的热耐受性。
