Figure 7.

Model of lipase action in P. fendleri oil accumulation. In many oilseeds TAG accumulates over seed development, then TAG levels drop ~10%–20% during seed maturation (blue line). (A) In P. fendleri recent results suggest an uncharacterized lipase is involved in remodeling 1HFA-TAG to 2HFA-TAG during TAG biosynthesis. (B) In wild-type P. fendleri PfeSDP1 action during late seed development and/or seed maturation leads to TAG turnover and the β-oxidation (β-ox.) of fatty acids reducing total oil amount. Some of the products of 2HFA-TAG turnover are remodeled into 1HFA-TAG. (C) The PfeSDP1_RNAi lines reduce TAG turnover and remodeling of 2HFA-TAG to 1HFA-TAG, thus increasing total oil amount (red dashed line) and HFA amount. Because PfeSDP1_RNAi lines only decreased expression of PfeSDP1 up to 50%, this result suggests a knockout mutation of PfeSDP1 may further increase seed oil.