Abstract
Membrane lipid remodeling contributes to the environmental acclimation of plants. In the green lineage, a betaine lipid, diacylglyceryl-N,N,N-trimethylhomoserine (DGTS), is included exclusively among green algae and nonflowering plants. Here, we show that the green alga Chlorella kessleri synthesizes DGTS under phosphorus-deficient conditions through the eukaryotic pathway via the ER. Simultaneously, phosphatidylcholine and phosphatidylethanolamine, which are similar to DGTS in their zwitterionic properties, are almost completely degraded to release 18.1% cellular phosphorus, and to provide diacylglycerol moieties for a part of DGTS synthesis. This lipid remodeling system that substitutes DGTS for extrachloroplast phospholipids to lower the P-quota operates through the expression induction of the BTA1 gene. Investigation of this lipid remodeling system is necessary in a wide range of lower green plants for a comprehensive understanding of their phosphorus deficiency acclimation strategies.
Highlights
Membrane lipid remodeling contributes to the environmental acclimation of plants
We previously reported that the membrane lipid metabolism in C. kessleri is similar to that in a seed plant, Arabidopsis thaliana, rather than to that in another green alga, C. reinhardtii
We found a DNA region that could encode a protein highly homologous to C. reinhardtii BTA1 gene (CrBTA1). cDNA covering this region was synthesized through 5′and 3′-RACE PCR with the use of total RNA isolated from C. kessleri cells starved of P as the template
Summary
Membrane lipid remodeling contributes to the environmental acclimation of plants. In the green lineage, a betaine lipid, diacylglyceryl-N,N,N-trimethylhomoserine (DGTS), is included exclusively among green algae and nonflowering plants. Phosphatidylcholine and phosphatidylethanolamine, which are similar to DGTS in their zwitterionic properties, are almost completely degraded to release 18.1% cellular phosphorus, and to provide diacylglycerol moieties for a part of DGTS synthesis This lipid remodeling system that substitutes DGTS for extrachloroplast phospholipids to lower the P-quota operates through the expression induction of the BTA1 gene. Information has accumulated on the remodeling of membrane lipids crucial for acclimation to some environmental stresses in photosynthetic organisms or for compensation of their mutational loss of some polar lipids[1,2]. Information on lipid remodeling is scarce for lower green plants under P-limited conditions, despite its potential involvement in their mechanism of acclimation to the P stress
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
