title: Phosphate deprivation induces transfer of DGDG galactolipid from chloroplast to mitochondria.
abstract: In many soils plants have to grow in a shortage of phosphate, leading to development of phosphate-saving mechanisms. At the cellular level, these mechanisms include conversion of phospholipids into glycolipids, mainly digalactosyldiacylglycerol (DGDG). The lipid changes are not restricted to plastid membranes where DGDG is synthesized and resides under normal conditions. In plant cells deprived of phosphate, mitochondria contain a high concentration of DGDG, whereas mitochondria have no glycolipids in control cells. Mitochondria do not synthesize this pool of DGDG, which structure is shown to be characteristic of a DGD type enzyme present in plastid envelope. The transfer of DGDG between plastid and mitochondria is investigated and detected between mitochondria-closely associated envelope vesicles and mitochondria. This transfer does not apparently involve the endomembrane system and would rather be dependent upon contacts between plastids and mitochondria. Contacts sites are favored at early stages of phosphate deprivation when DGDG cell content is just starting to respond to phosphate deprivation.
authors.affiliation: Laboratoire de Physiologie Cellulaire Végétale, UMR 5168 (CNRS/CEA/Université Jseph Fourier/INRA), DRDC-PCV, CEA-Grenoble, Grenoble, France.
authors.forename: Juliette
authors.initials: J
authors.lastname: Jouhet
authors.forename: Eric
authors.initials: E
authors.lastname: Maréchal
authors.forename: Barbara
authors.initials: B
authors.lastname: Baldan
authors.forename: Richard
authors.initials: R
authors.lastname: Bligny
authors.forename: Jacques
authors.initials: J
authors.lastname: Joyard
authors.forename: Maryse A
authors.initials: MA
authors.lastname: Block
mesh_terms: D017360:Arabidopsis / Q000378:metabolism* / Q000648:ultrastructure; D002478:Cells, Cultured; D002736:Chloroplasts / Q000378:metabolism* / Q000648:ultrastructure; D005508:Food Deprivation / Q000502:physiology; D038983:Galactolipids / Q000378:metabolism*; D007425:Intracellular Membranes / Q000378:metabolism / Q000648:ultrastructure; D046529:Microscopy, Electron, Transmission; D008928:Mitochondria / Q000378:metabolism*; D010710:Phosphates / Q000378:metabolism*; D010743:Phospholipids / Q000378:metabolism; D010758:Phosphorus / Q000378:metabolism; D022161:Transport Vesicles / Q000378:metabolism / Q000648:ultrastructure
chemical_list: D038983:Galactolipids; D010710:Phosphates; D010743:Phospholipids; C007388:digalactosyldiacylglycerol; D010758:Phosphorus