Abstract Some extant deep-sea shrimp are known to be descended from shallow-water ancestors that adapted to environmental conditions (constant low temperature and high hydrostatic pressure) in the deep sea. During acclimation to low temperature and high hydrostatic pressure representative of the deep-sea, critical thermal tolerance decreases and critical pressure tolerance increases in the shallow-water shrimp Palaemon varians. It has been suggested that these shifts may depend in part on adjustments to phospholipid fatty acid composition and/or metabolic adjustments. Here, we present evidence that metabolic rate does not change during sustained exposure to low temperature (5 °C) in the shallow-water shrimp Palaemon varians, and that metabolic rate and acute environmental tolerances are not correlated during sustained exposure to low temperature, suggesting that standard metabolic rate does not affect acute environmental tolerances. In contrast, we present evidence that phospholipid fatty acid composition does shift during sustained exposure to low temperature. Desaturation of fatty acids during sustained exposure to low temperature supports the suggestion that cell lipid bilayer homeoviscous modifications are important in low temperature acclimation. Shifts in several individual phospholipid fatty acids during sustained low temperature exposure are correlated with critical thermal tolerance. Exploring the greater complexity apparent in the responses of these phospholipid fatty acids to sustained low temperature exposures suggests a potential homeostatic impact moderating adverse impacts on nervous system function. However, shifts in phospholipid fatty acids are not correlated with critical pressure tolerance during exposure to low temperature, suggesting that shifts in critical pressure tolerance are related to modifications other than cell lipid bilayer composition.

中文翻译：

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在持续暴露于低温期间，磷脂脂肪酸与临界热耐受性相关，但与浅水虾Palaemon varians的临界压力耐受性无关

摘要 已知一些现存的深海虾是适应深海环境条件（恒定低温和高静水压力）的浅水祖先的后代。在适应代表深海的低温和高静水压力的过程中，浅水对虾的临界热耐受性降低，而临界压力耐受性增加。有人提出，这些变化可能部分取决于对磷脂脂肪酸组成和/或代谢调整的调整。在这里，我们提供的证据表明，在浅水对虾持续暴露于低温（5°C）期间，代谢率不会发生变化，并且在持续暴露于低温期间，代谢率和急性环境耐受性没有相关性，表明标准代谢率不会影响急性环境耐受性。相比之下，我们提供的证据表明，在持续暴露于低温期间，磷脂脂肪酸组成确实会发生变化。在持续暴露于低温期间脂肪酸的去饱和支持细胞脂质双层自体粘性修饰在低温驯化中很重要的建议。在持续低温暴露期间几种单独的磷脂脂肪酸的变化与临界热耐受性相关。探索这些磷脂脂肪酸对持续低温暴露的反应的更大复杂性表明，潜在的稳态影响可以缓和对神经系统功能的不利影响。然而，