It is unclear how changes in lipid droplet size and number are regulated - for example, it is not known whether this involves a signalling pathway or is directed by cellular lipid uptake. Here, we show that oleic acid stimulates lipid droplet formation by activating the long-chain fatty acid receptor FFAR4, which signals through a pertussis-toxin-sensitive G-protein signalling pathway involving phosphoinositide 3-kinase (PI3-kinase), AKT (also known as protein kinase B) and phospholipase D (PLD) activities. This initial lipid droplet formation is not dependent upon exogenous lipid, whereas the subsequent more sustained increase in the number of lipid droplets is dependent upon lipid uptake. These two mechanisms of lipid droplet formation point to distinct potential intervention points.

作者：Arndt, Rohwedder；Qifeng, Zhang；Simon A, Rudge；Michael J O, Wakelam

来源：Journal of cell science 2014 年 127卷 Pt 14期