Abstract
Phosphatidate phosphatase (PAP) is the enzyme which produces diacylglycerol (DAG) by dephosphorylating phosphatidic acid (PA). PAPs play an important role in glycerolipid metabolism since DAG is a common precursor of biosynthesis for glycolipid,phospholipid and neutral lipid (triacylglycerol).
We recently reported lipid phosphate phosphatases (LPP) which are localized to plastids in Arabidopsis (Nakamura et al. (2007) J Biol Chem, 282: 29013-29021). Here, we identified a novel type of PAP (PAH1, PAH2). Analysis for their mutant lines showed that pah1 and pah2 single mutants had no change in lipid metabolism, whereas in a pah1pah2 double mutant accumlation of PA, alteration of the lipid composition and morphological change in leaves were observed. Role of PAPs in lipid metabolism under Pi-sufficient and Pi-depleted conditions will be discussed in this presentation.
