Fraser Keiron P P, Peck Lloyd S, Clark Melody S, Clarke Andrew, Hill Simeon L
Marine Station, University of Plymouth, Artillery Place, Coxside, Plymouth PL4 OLU, UK.
British Antarctic Survey, Natural Environment Research Council, High Cross, Madingley Road, Cambridge CB3 OET, UK.
R Soc Open Sci. 2022 Mar 9;9(3):211272. doi: 10.1098/rsos.211272. eCollection 2022 Mar.
Whole-animal, protein metabolism rates have been reported in temperate and tropical, but not Antarctic fish. Growth in Antarctic species is generally slower than lower latitude species. Protein metabolism data for Antarctic invertebrates show low rates of protein synthesis and unusually high rates of protein degradation. Additionally, in Antarctic fish, increasing evidence suggests a lower frequency of successful folding of nascent proteins and reduced protein stability. This study reports the first whole-animal protein metabolism data for an Antarctic fish. Groups of Antarctic, , and temperate, , fish were acclimatized to a range of overlapping water temperatures and food consumption, whole-animal growth and protein metabolism measured. The rates of protein synthesis and growth in Antarctic, but not temperate fish, were relatively insensitive to temperature and were significantly lower in at 3°C than in . Protein degradation was independent of temperature in and not significantly different to at 3°C, while protein synthesis retention efficiency was significantly higher in than at 3°C. These results suggest Antarctic fish degrade a significantly larger proportion of synthesized protein than temperate fish, with fundamental energetic implications for growth at low temperatures.
关于全动物蛋白质代谢率，已有在温带和热带鱼类中的报道，但南极鱼类尚无此类报道。南极物种的生长速度通常比低纬度物种慢。南极无脊椎动物的蛋白质代谢数据显示，其蛋白质合成速率低，蛋白质降解速率异常高。此外，在南极鱼类中，越来越多的证据表明新生蛋白质成功折叠的频率较低，蛋白质稳定性降低。本研究报告了首例南极鱼类的全动物蛋白质代谢数据。将南极鱼类和温带鱼类分组，使其适应一系列重叠的水温，并测量食物消耗量、全动物生长和蛋白质代谢情况。南极鱼类而非温带鱼类的蛋白质合成和生长速率对温度相对不敏感，在3°C时，南极鱼类的蛋白质合成和生长速率显著低于温带鱼类。南极鱼类的蛋白质降解与温度无关，在3°C时与温带鱼类无显著差异，而在3°C时，南极鱼类的蛋白质合成保留效率显著高于温带鱼类。这些结果表明，与温带鱼类相比，南极鱼类降解的合成蛋白质比例要大得多，这对低温下的生长具有重要的能量意义。
