We found that plants adapt to frequent alterations between high and low temperatures by remodeling of membrane lipids and maintenance of unsaturation levels. This mechanism is distinct from that adapting to slow alterations in temperature. We found that the acyl chain lengths of phosphatidylserine lengthen during development, senescence, and stresses and that increasing length was accelerated by promoted-senescence. The lengthening of its acyl chains stopped when plants were close to death. This provides a molecular scale ruler for measuring plant development and for determining plant lifespan. We found that plants exhibit differential degradation of extraplastidic and plastidic lipids during freezing and post-freezing recovery. This work was highlighted by Nature China . We demonstrated that sensitivity of recalcitrant seeds to desiccation is mainly due to the formation of phosphatidic acid in the membrane and that phospholipase Dα1 and its translocation from cytosol to plasma membrane is responsible for this phosphatidic acid formation.
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