The phospho-base N-methyltransferases PMT1 and PMT2 produce phosphocholine for leaf growth in phosphorus-starved Arabidopsis. (22nd October 2021)

• Record Type: Journal Article
• Authors: Ngo, Anh H; Angkawijaya, Artik Elisa; Lin, Ying-Chen; Liu, Yu-chi; Nakamura, Yuki
• Editors: Dietz, Karl-Josef
• Is Part Of: Journal of experimental botany. Volume 73:Number 9(2022)
• Page Start: 2985
• Page End: 2994
• Publication Date: 2021-10-22
• Subjects: Arabidopsis thaliana -- membrane lipid remodeling -- phospho-base N-methyltransferase -- phosphocholine -- phospholipid -- phosphorus starvation; Botany -- Periodicals; Botany, Experimental -- Periodicals; Plant physiology -- Periodicals; 580
• DOI: 10.1093/jxb/erab436
• Languages: English
• ISSNs: 0022-0957

Abstract

Abstract: Phosphorus (P) is an essential nutrient for plants. Membrane lipid remodeling is an adaptive mechanism for P-starved plants that replaces membrane phospholipids with non-P galactolipids, presumably to retrieve scarce P sources and maintain membrane integrity. Whereas metabolic pathways to convert phospholipids to galactolipids are well-established, the mechanism by which phospholipid biosynthesis is involved in this process remains elusive. Here, we report that phospho-base N -methyltransferases 1 and 2 (PMT1 and PMT2), which convert phosphoethanolamine to phosphocholine (PCho), are transcriptionally induced by P starvation. Shoots of seedlings of pmt1 pmt2 double mutant showed defective growth upon P starvation; however, membrane lipid profiles were unaffected. We found that P-starved pmt1 pmt2 with defective leaf growth had reduced PCho content, and the growth defect was rescued by exogenous supplementation of PCho. We propose that PMT1 and PMT2 are induced by P starvation to produce PCho mainly for leaf growth maintenance, rather than for phosphatidylcholine biosynthesis, in membrane lipid remodeling. Abstract : A pair of phospho-base N -methyltransferases, PMT1 and PMT2, are induced by phosphate starvation and produce phosphocholine that is required for the seedling growth of phosphate-starved Arabidopsis.