title: Monensin blocks the transfer of very long chain fatty acid containing lipids to the plasma membrane of leek seedlings. Evidence for lipid sorting based on fatty acyl chain length.
abstract: Delivery of newly synthesized fatty acids and lipids to the plasma membrane in leek seedlings via the endoplasmic reticulum (ER)-Golgi apparatus pathway is primarily by bulk transport (without sorting). However, pulse-chase experiments revealed kinetics of transport of lipids with VLCFA (very long chain fatty acids having more than 18 carbon atoms) in favor of a preferential transfer of these molecules to the plasma membrane. Use of monensin showed the accumulation of lipids in the Golgi apparatus and a related decrease of the amount of lipids transported to the plasma membrane. Lipid and fatty acid analyses revealed that transport of VLCFA-containing phospholipids was most strongly inhibited by the monensin block. These results taken together with an inability of the plasma membrane to synthesize VLCFA support a role for the Golgi apparatus in VLCFA delivery to the plasma membrane and leads to the hypothesis of a sorting function as well, based on fatty acyl chain length.
authors.affiliation: Institut de Biochimie et Neurochimie du CNRS, Université de Bordeaux II, France.
authors.forename: P
authors.initials: P
authors.lastname: Bertho
authors.forename: P
authors.initials: P
authors.lastname: Moreau
authors.forename: D J
authors.initials: DJ
authors.lastname: Morré
authors.forename: C
authors.initials: C
authors.lastname: Cassagne
mesh_terms: D000490:Allium; D001692:Biological Transport / Q000187:drug effects; D002458:Cell Fractionation; D002462:Cell Membrane / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D004721:Endoplasmic Reticulum / Q000378:metabolism; D005227:Fatty Acids / Q000737:chemistry / Q000378:metabolism*; D006056:Golgi Apparatus / Q000378:metabolism; D008563:Membrane Lipids / Q000378:metabolism; D008854:Microscopy, Electron; D008985:Monensin / Q000494:pharmacology*; D012639:Seeds
chemical_list: D005227:Fatty Acids; D008563:Membrane Lipids; D008985:Monensin