Arabidopsis lipins mediate eukaryotic pathway of lipid metabolism and cope critically with phosphate starvation

• DOI: 10.1073/pnas.0907173106
• Publication Date: 2009-11-19T03:19:24Z
• Authors: Yuki Nakamura; Ryota Koizumi; Guanghou Shui; Mie Shimojima; Markus R. Wenk; Toshiro Ito; Hiroyuki Ohta
• Keywords: Phosphatidate; Galactolipids; Phospholipase D; Galactolipids

Phosphate is an essential nutrient for plant viability. It well-established that phosphate starvation triggers membrane lipid remodeling, a process converts significant portion of phospholipids to non-phosphorus-containing galactolipids. This remodeling mediated by either phospholipase C (PLC) or D (PLD) in combination with phosphatidate phosphatase (PAP). Two PLC genes, NPC4 and NPC5, PLD PLDzeta1 PLDzeta2, are shown be involved the remodeling. However, gene knockout studies show none them plays decisive roles Thus, although this phenomenon widely observed among plants, key enzyme(s) responsible whole body unknown; therefore, physiological significance conversion has remained elucidated. We herein focused on PAP as enzyme adaptation, identified Arabidopsis lipin homologs, AtPAH1 AtPAH2, encode PAPs galactolipid biosynthesis. Double mutant pah1pah2 plants had decreased phosphatidic acid hydrolysis, thus affecting eukaryotic pathway synthesis. Upon starvation, were severely impaired growth These results indicate PAH1 PAH2 synthesis, these two enzymes adaptation mechanism cope starvation.