Plant lipidomics temperature

In another study, the changes of lipidomes in response to temperature were conducted as a temperature-dependent manner (i.e., at 4, 21, and 32 °C) by LC-MS [13]. In addition to the previous findings as described earlier, it was also found that an immediate decrease in unsaturated species of PG was present in plants under high-temperature conditions (i.e., 32 °C). This finding suggests that the reduction of unsaturation in PG species could be the first stages of adaptation to heat stress conditions. 

So next question is which PLD isoform(s) play the essential role in plants in response to low temperatures, leading to the increase in the levels of PA species. Further studies by lipidomics revealed that suppression of PLDal led to a higher level of PC species, but a lower level of PA species [6], These results indicated that PC was the major in vivo substrate for PLDal under freezing conditions. In fact, PLDal was responsible for 50% of PC hydrolyzed under the freezing conditions tested [6], The lack of difference between wild-type and PLDal-deficient plants in the levels of PE and PG species suggests that other enzymes in addition to PLDal were responsible for the freezing-induced hydrolysis of PE and PG species. 

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