Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1253347 | Chemistry and Physics of Lipids | 2014 | 10 Pages |
•Cardiolipin is synthesized in mitochondria, secondarily modified, and shows heterogeneous distribution.•Cardiolipin/phospholipids move between the two mitochondrial membranes and adjacent ER membranes.•Lipid trafficking is supported by contact sites induced by different protein complexes.•Intermembrane lipid transfer involves specific contact site complexes and lipid transfer proteins.•Intramembrane lipid transfer between leaflets may also depend on specific proteins.
Historically, cellular trafficking of lipids has received much less attention than protein trafficking, mostly because its biological importance was underestimated, involved sorting and translocation mechanisms were not known, and analytical tools were limiting. This has changed during the last decade, and we discuss here some progress made in respect to mitochondria and the trafficking of phospholipids, in particular cardiolipin. Different membrane contact site or junction complexes and putative lipid transfer proteins for intra- and intermembrane lipid translocation have been described, involving mitochondrial inner and outer membrane, and the adjacent membranes of the endoplasmic reticulum. An image emerges how cardiolipin precursors, remodeling intermediates, mature cardiolipin and its oxidation products could migrate between membranes, and how this trafficking is involved in cardiolipin biosynthesis and cell signaling events. Particular emphasis in this review is given to mitochondrial nucleoside diphosphate kinase D and mitochondrial creatine kinases, which emerge to have roles in both, membrane junction formation and lipid transfer.