Low Temperature-Induced GA3 Sensitivity of Wheat 1: II. Changes in Lipids Associated with the Low Temperature-Induced GA3 Sensisivity of Isolated Aleurone of Kite

摘要

Exposure of isolated aleurone tissue from the wheat (Triticum aestivum) variety Kite which contains the Rht2 allele, to low temperature (5°C) for 20 h prior to addition of exogenous GA3, resulted in significant changes in the content of lipids, especially phospholipids. Significant low temperature-induced changes in both the head group and acyl contents of two phospholipids, phosphatidylcholine and phosphatidylethanolamine, were detected. More importantly, these changes displayed a very close temporal relationship with the low temperature-induced increase in GA3 sensitivity. Further, this relationship was paralleled by a highly significant correlation between the changes in the phospholipids and the changes in α-amylase production. These results underline the possibility that the GA3 receptor sites are membrane-based lipids.