The product of LPAT is phosphatidate, which, in seeds, is quickly
dephosphorylated by a phosphatidate phosphatase to diacylglycerol, which is the substrate for the last enzyme of this pathway
the acyl-CoA: diacylglycerol acyltransferase (DGAT). This enzyme
acylates the last position of the glycerol backbone to produce
TAG [67]. In developing seeds TAG accumulates in structures
known as oleosomes, consisting of small drops of oil surrounded
by a monolayer of phospholipid. The outer surface contains proteins like oleosins, catoleosins and steroleosins that confer stability
to the oil droplets and prevent their coalescence [68]. Oleosomes
show important changes upon germination, when a shift in their
protein composition takes place. Then, TAG lipases [69], phospholipases [70] and 13-lipoxygenases [71] bind to this organelle to
mobilize the TAGs that are later degraded as a source of carbon
and reducing equivalents for the germinating embryo.