biostudies-literatureKelly AAU.S. Department of EnergyDeutsche ForschungsgemeinschaftWenner-Gren Foundation10714-9https://www.ebi.ac.uk/biostudies/studies/S-EPMC5035899biostudies-literatureUnknown113(38)Galactolipids [monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG)] are the hallmark lipids of photosynthetic membranes. The galactolipid synthases MGD1 and DGD1 catalyze consecutive galactosyltransfer reactions but localize to the inner and outer chloroplast envelopes, respectively, necessitating intermembrane lipid transfer. Here we show that the N-terminal sequence of DGD1 (NDGD1) is required for galactolipid transfer between the envelopes. Different diglycosyllipid synthases (DGD1, DGD2, and Chloroflexus glucosyltransferase) were introduced into the dgd1-1 mutant of Arabidopsis in fusion with N-terminal extensions (NDGD1 and NDGD2) targeting to the outer envelope. Reconstruction of DGDG synthesis in the outer envelope membrane was observed only with diglycosyllipiProceedings of the National Academy of Sciences of the United States of AmericaSynthesis and transfer of galactolipids in the chloroplast envelope membranes of Arabidopsis thaliana.PMC5035899DE-FG02-98ER20305FellowshipSFB645Do520/10Melzer MKelly AASchulze SRoston RLKalisch BThiele JDormann PHolzl GBenning CfalseSynthesis and transfer of galactolipids in the chloroplast envelope membranes of Arabidopsis thaliana.Galactolipids [monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG)] are the hallmark lipids of photosynthetic membranes. The galactolipid synthases MGD1 and DGD1 catalyze consecutive galactosyltransfer reactions but localize to the inner and outer chloroplast envelopes, respectively, necessitating intermembrane lipid transfer. Here we show that the N-terminal sequence of DGD1 (NDGD1) is required for galactolipid transfer between the envelopes. Different diglycosyllipid synthases (DGD1, DGD2, and Chloroflexus glucosyltransferase) were introduced into the dgd1-1 mutant of Arabidopsis in fusion with N-terminal extensions (NDGD1 and NDGD2) targeting to the outer envelope. Reconstruction of DGDG synthesis in the outer envelope membrane was observed only with diglycosyllipi2016-01-01T00:00:00Z2016 Sep2026-05-05T05:44:25.653Z2019-03-27T02:25:04ZS-EPMC50358992760165810.1073/pnas.1609184113