Diacylglycerol acyltransferase 1 contributes to freezing tolerance

Low temperature is one of the environmental factors limiting the plant distribution. Yet there are some plants that can survive freezing temperatures, such as Boechera stricta, native to the Rocky Mountains, spread across a broad range of elevations. Arisz and colleagues observed that freezing tolerance was higher in the LTM ecotype (found in the northern high range) than in the SAD12 ecotype (native to southern slopes.) The QTL analysis of the bi-parental population identified a locus containing CoA:diacylglycerol O-acyltransferase 1 (DGAT1). The expression of BsDGAT1 was observed to be higher in the LTM ecotype and corresponded with higher levels of triacylglycerol. Overexpression of Arabidopsis DGAT1 resulted in increased freezing tolerance. The authors speculate that DGAT1 might be specifically important for protecting the membrane fluidity of the chloroplasts in freezing temperatures. (Summary by Magdalena Julkowska) Plant Physiol. 10.1104/pp.18.00503