Brooks S, Clark G T, Wright S M, Trueman R J, Postle A D, Cossins A R, Maclean N M
Department of Cell Sciences, School of Biological Sciences, University of Southampton, UK.
J Exp Biol. 2002 Dec;205(Pt 24):3989-97. doi: 10.1242/jeb.205.24.3989.
Cold acclimation of carp from 30 degrees C to 10 degrees C causes a restructuring of liver microsomal phospholipids characterised by increased proportions of monounsaturated fatty acid in phosphatidylcholine (PC) and phosphatidylethanolamine (PE). Here, we have used electrospray ionisation mass spectrometry (ESI-MS) to determine the patterns of alteration to individual molecular species compositions of PC, PE and phosphatidylinositol (PI) in response to gradually decreasing temperature. The results demonstrate that cold induces precise changes to a limited number of phospholipid species, and that these changes are distinct and different for each phospholipid class. The major change for PC was increased 16:1/22:6, but for PE the species that increased was 18:1/22:6. By contrast, the PI species that increased during cold acclimation were characterised by an sn-1 monounsaturated fatty acid in combination with arachidonoyl or eicosapentaenoyl fatty acid at the sn-2 position. Analysis of acyl distribution indicates that cold only caused the accumulation of monounsaturated fatty acids at the sn-1 and not at the sn-2 position of phospholipids. These results highlight the tight and restricted range of modifications that membranes make to their phospholipid composition in response to thermal stress.
将鲤鱼从30摄氏度冷驯化至10摄氏度会导致肝脏微粒体磷脂发生重组，其特征是磷脂酰胆碱（PC）和磷脂酰乙醇胺（PE）中单不饱和脂肪酸的比例增加。在此，我们使用电喷雾电离质谱（ESI-MS）来确定随着温度逐渐降低，PC、PE和磷脂酰肌醇（PI）的各个分子种类组成的变化模式。结果表明，寒冷会诱导有限数量的磷脂种类发生精确变化，并且这些变化对于每种磷脂类别而言都是独特且不同的。PC的主要变化是16:1/22:6增加，而对于PE而言，增加的种类是18:1/22:6。相比之下，冷驯化期间增加的PI种类的特征是在sn-1位有一个单不饱和脂肪酸，在sn-2位与花生四烯酰基或二十碳五烯酰基脂肪酸结合。酰基分布分析表明，寒冷仅导致磷脂sn-1位单不饱和脂肪酸的积累，而不是sn-2位。这些结果突出了膜在响应热应激时对其磷脂组成进行修饰的紧密且受限的范围。
