Inter-individual variation in mitochondrial phosphorylation efficiency predicts growth rates in ectotherms at high temperatures.
Inter-individual variation in mitochondrial phosphorylation efficiency predicts growth rates in ectotherms at high temperatures.
复制标题
线粒体磷酸化效率的个体间差异预测了变温动物在高温下的生长速率。
DOI：
10.1096/fj.202101806rr
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Dawson NJ
中科院分区：
文献类型：
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作者：
Dawson NJ
越来越多的证据表明，水生外温动物特别容易受到全球变暖的影响，因为它们的新陈代谢需求随着环境温度的升高而增加，而水-氧含量则减少。有氧范围缩小在限制运动能力中的可能作用已经讨论了很多；然而，对于组织水平的氧气利用效率是否在高温下发生变化的关注较少。在这里，我们展示了这一点在不同的人之间有很大的不同，并会对绩效产生影响。我们研究了适应高温度(19.5℃)或接近最适温度(12℃)的褐鲑鱼(Salmo Trutta)白肌肉和肝脏的生长速度和线粒体功能的个体间差异。肝脏(而不是肌肉)线粒体的生长速度与两种温度下的最大氧化磷酸化水平呈正相关，与ROS释放呈负相关。在这两个组织中，个体线粒体的磷酸化效率和生长速率之间存在正相关，但仅在19.5℃。在这种典型的水生外温动物中，个体的肝脏线粒体效率似乎决定了其在高温下生长的能力。这表明细胞功能的个体异质性可能导致水生外温动物温度极限的变化，并可能对气候变暖环境中的野生种群产生不利影响。
There is increasing evidence that aquatic ectotherms are especially vulnerable to global warming since their metabolic demands increase with ambient temperature while water‐oxygen content decreases. The possible role of shrinking aerobic scope in limiting performance has been much discussed; however, less attention has been given to whether tissue‐level changes in the efficiency of oxygen usage occur at elevated temperatures. Here, we show that this varies widely among individuals, with consequences for performance. We examined the inter‐individual variation in growth rate and mitochondrial function from white muscle and liver of brown trout (Salmo trutta) acclimated to either high (19.5°C) or near‐optimal temperature (12°C). Liver (but not muscle) mitochondria showed a positive relationship between growth rate and maximal oxidative phosphorylation at both temperatures, and a negative relationship between growth rate and ROS release. There was a positive correlation in both tissues between individual mitochondrial phosphorylation efficiency and growth rate, but only at 19.5°C. In this representative of aquatic ectotherms, an individual's liver mitochondrial efficiency thus seems to dictate its capacity to grow at elevated temperatures. This suggests that individual heterogeneity in cellular function may cause variation in the thermal limits of aquatic ectotherms and could adversely affect wild populations in warming environments.