Lipid profiling shows tissue-specific differences in barley for glycerolipid composition in response to chilling

Glycerolipids are the main constituent of cellular membranes, and their remodelling plays an important role in how plants adapt to temperature. However, little is known about the differences between plant tissues in terms of glycerolipid response to low temperatures. Using lipidomics-based ESI-MS/MS coupled with statistical analysis, we compared the glycerolipidome of barley plants grown at 25 degrees C with that of plants exposed to chilling temperature (4 degrees C). We found that the level of phospholipids and galactolipids was higher in roots than in leaves, although the phospholipid to galactolipids ratio was similar for both tissues. Compared with plants grown at 25 degrees C, the chilling treatment produced contrasting responses in phospholipids and galactolipids. A slight increasing trend in unsaturated fatty acid-enriched phospholipids can be observed in leaves during short-term chilling. By contrast, there is a decrease in plastidic and extraplastidic phospholipids in roots during long-term chilling. The contrasting and spatial-temporal behaviour of the plant tissues could suggest a particular chilling sensing mechanism in response to external environmental fluctuations.