CSIRO Entomology, GPO Box 1700, Canberra, ACT 2601, Australia.
J Insect Physiol. 2010 Jan;56(1):1-7. doi: 10.1016/j.jinsphys.2009.07.014.
In contrast to the majority of the Order, the dampwood termites of the family Termopsidae found in colder regions can experience frost and snow, either in cool temperate areas at high latitudes (45 degrees ), or alpine areas at high elevations (>1000m). This suggests that dampwood termites are adapted to cold climates. We investigated this hypothesis in two dampwood termites, Porotermes adamsoni Froggatt and Stolotermes victoriensis Hill. We measured nest temperatures and atmospheric temperatures of their alpine habitat during winter, and measured survival and recovery at subzero temperatures. We also determined the minimum temperature at which these species remain active and the LT50 values. We used a novel gas chromatographic strategy to examine eight metabolites from individuals of both species collected in winter and summer to identify possible cryoprotectants. Both P. adamsoni and S. victoriensis had significantly higher levels of trehalose, a known cryoprotectant, in winter than in summer; in addition S. victoriensis also had higher levels of unsaturated fatty acid ligands in winter than in summer, consistent with patterns observed for cold adaptation in other organisms. These results are the first to reveal that dampwood termites are adapted to cold climates and use trehalose and unsaturated lipids as cryoprotectants.
与大多数目不同，在较冷地区发现的科（Termopsidae）的湿木白蚁可以经历霜和雪，无论是在高纬度（45 度）的凉爽温带地区，还是在高海拔（>1000m）的高山地区。这表明湿木白蚁适应寒冷的气候。我们在两种湿木白蚁，Porotermes adamsoni Froggatt 和 Stolotermes victoriensis Hill 中研究了这一假说。我们测量了冬季巢内温度和高山栖息地的大气温度，并在亚零温度下测量了存活率和恢复率。我们还确定了这些物种保持活跃的最低温度和 LT50 值。我们使用一种新颖的气相色谱策略来检查两种物种在冬季和夏季采集的个体中的八种代谢物，以确定可能的冷冻保护剂。Porotermes adamsoni 和 Stolotermes victoriensis 在冬季的海藻糖水平均显著高于夏季，海藻糖是一种已知的冷冻保护剂；此外，Stolotermes victoriensis 在冬季的不饱和脂肪酸配体水平也高于夏季，与其他生物体适应寒冷的模式一致。这些结果首次表明湿木白蚁适应寒冷的气候，并使用海藻糖和不饱和脂质作为冷冻保护剂。
