Real-time tracking of lipid droplets interactions with other organelles by a high signal/noise probe

Abstract Investigating the interactions between lipid droplets (LDs) and other organelles are greatly significant to the in-depth understand the physiology and pathology of LDs. Despite of commercial LDs probes available, the ER and other membrane structures are also stained due to their amphiphilicity, which limits their further applications. To address this issue, we herein report a highly hydrophobic fluorescent probe to specifically label intracellular LDs with high signal/noise ratio, avoiding undesirable staining of ER and thus achieving to real-time monitor the interactions between LDs and other organelles. The probe showed strong emission in lipid environments but no fluorescence in water and liposomes, enabling the probe with high signal/noise ratio. Using this probe, it was found that the contacts of LDs with ER and mitochondria clearly increased under the condition of starvation.