title: Dictyostelium lipid droplets host novel proteins.
abstract: Across all kingdoms of life, cells store energy in a specialized organelle, the lipid droplet. In general, it consists of a hydrophobic core of triglycerides and steryl esters surrounded by only one leaflet derived from the endoplasmic reticulum membrane to which a specific set of proteins is bound. We have chosen the unicellular organism Dictyostelium discoideum to establish kinetics of lipid droplet formation and degradation and to further identify the lipid constituents and proteins of lipid droplets. Here, we show that the lipid composition is similar to what is found in mammalian lipid droplets. In addition, phospholipids preferentially consist of mainly saturated fatty acids, whereas neutral lipids are enriched in unsaturated fatty acids. Among the novel protein components are LdpA, a protein specific to Dictyostelium, and Net4, which has strong homologies to mammalian DUF829/Tmem53/NET4 that was previously only known as a constituent of the mammalian nuclear envelope. The proteins analyzed so far appear to move from the endoplasmic reticulum to the lipid droplets, supporting the concept that lipid droplets are formed on this membrane.
authors.affiliation: Abteilung Zellbiologie.
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Du
authors.forename: Caroline
authors.initials: C
authors.lastname: Barisch
authors.forename: Peggy
authors.initials: P
authors.lastname: Paschke
authors.forename: Cornelia
authors.initials: C
authors.lastname: Herrfurth
authors.forename: Oliver
authors.initials: O
authors.lastname: Bertinetti
authors.forename: Nadine
authors.initials: N
authors.lastname: Pawolleck
authors.forename: Heike
authors.initials: H
authors.lastname: Otto
authors.forename: Harald
authors.initials: H
authors.lastname: Rühling
authors.forename: Ivo
authors.initials: I
authors.lastname: Feussner
authors.forename: Friedrich W
authors.initials: FW
authors.lastname: Herberg
authors.forename: Markus
authors.initials: M
authors.lastname: Maniak
mesh_terms: D000595:Amino Acid Sequence; D004023:Dictyostelium / Q000378:metabolism*; D004721:Endoplasmic Reticulum / Q000378:metabolism; D008969:Molecular Sequence Data; D010743:Phospholipids / Q000737:chemistry / Q000378:metabolism*; D021381:Protein Transport; D015800:Protozoan Proteins / Q000737:chemistry / Q000378:metabolism*
chemical_list: D010743:Phospholipids; D015800:Protozoan Proteins
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