Elder Leanne E, Seibel Brad A
Biological Sciences Department, University of Rhode Island, 120 Flagg Road, Kingston, RI 02881, USA.
Biological Sciences Department, University of Rhode Island, 120 Flagg Road, Kingston, RI 02881, USA.
Comp Biochem Physiol A Mol Integr Physiol. 2015 Sep;187:20-6. doi: 10.1016/j.cbpa.2015.04.008. Epub 2015 Apr 18.
The hyperiid amphipod Phronima sedentaria experiences a temperature change of 15 °C during diel migration in the Eastern Tropical North Pacific (ETNP) from 8-10 °C at depth to 25-27 °C at night in the surface waters. The aim of this study was to determine if the natural temperature gradient experienced by P. sedentaria results in a thermal stress response. Individuals were initially exposed to their night time temperatures (23 °C) and subsequently subjected to temperatures within and above the range they typically experience. In the Eastern Tropical North Pacific P. sedentaria tolerates its normal night-time temperature (23 °C), but only for the duration of its stay there (9 h). Longer exposures (24 h) result in elevated heat shock protein (hsp) expression. 29 °C results in hsp expression, increased lactate production and 50% mortality at all exposure durations. This represents an upper critical temperature. Understanding the adaptations of pelagic amphipods to their current environment will help predict the physiological impacts of global warming for amphipods and their predators.
在东热带北太平洋（ETNP），超体型端足类动物Phronima sedentaria在昼夜垂直迁移过程中经历了15°C的温度变化，从深处8 - 10°C到夜间表层水域的25 - 27°C。本研究的目的是确定Phronima sedentaria所经历的自然温度梯度是否会导致热应激反应。个体最初暴露于夜间温度（23°C），随后经受其通常经历温度范围内及以上的温度。在东热带北太平洋，Phronima sedentaria能耐受其正常夜间温度（约23°C），但仅在其停留于此的时间段内（约9小时）。更长时间的暴露（24小时）会导致热休克蛋白（hsp）表达升高。在所有暴露时长下，29°C会导致hsp表达、乳酸产量增加以及50%的死亡率。这代表了一个上限临界温度。了解远洋端足类动物对其当前环境的适应性将有助于预测全球变暖对端足类动物及其捕食者的生理影响。
