Details

Autor(en) / Beteiligte

• Penno, Anke
• Hackenbroich, Gregor
• Thiele, Christoph

Titel

Phospholipids and lipid droplets

Ist Teil von

• Biochimica et biophysica acta, 2013-03, Vol.1831 (3), p.589-594

Ort / Verlag

Netherlands: Elsevier B.V

Erscheinungsjahr

2013

Link zum Volltext

Quelle

Elsevier ScienceDirect Journals Complete

Beschreibungen/Notizen

• Lipid droplets are ubiquitous cellular organelles that allow cells to store large amounts of neutral lipids for membrane synthesis and energy supply in times of starvation. Compared to other cellular organelles, lipid droplets are structurally unique as they are made of a hydrophobic core of neutral lipids and are separated to the cytosol only by a surrounding phospholipid monolayer. This phospholipid monolayer consists of over a hundred different phospholipid molecular species of which phosphatidylcholine is the most abundant lipid class. However, lipid droplets lack some indispensable activities of the phosphatidylcholine biogenic pathways suggesting that they partially depend on other organelles for phosphatidylcholine synthesis. Here, we discuss very recent data on the composition, origin, transport and function of the phospholipid monolayer with a particular emphasis on the phosphatidylcholine metabolism on and for lipid droplets. In addition, we highlight two very important quantitative aspects: (i) The amount of phospholipid required for lipid droplet monolayer expansion is remarkably small and (ii) to maintain the invariably round shape of lipid droplets, a cell must have a highly sensitive but so far unknown mechanism that regulates the ratio of phospholipid to neutral lipid in lipid droplets. This article is part of a Special Issue entitled Phospholipids and Phospholipid Metabolism. ► Lipid droplets are surrounded by phospholipid monolayers. ► Biosynthesis of droplet phospholipids occurs at different sites. ► The amount of droplet phospholipid is tightly regulated. ► Geometrical factors determine the ratio of phospholipid and neutral lipid.