National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China.
Protein Cell. 2011 Jun;2(6):487-96. doi: 10.1007/s13238-011-1061-y. Epub 2011 Jul 12.
An increasing body of evidence shows that the lipid droplet, a neutral lipid storage organelle, plays a role in lipid metabolism and energy homeostasis through its interaction with mitochondria. However, the cellular functions and molecular mechanisms of the interaction remain ambiguous. Here we present data from transmission electron microscopy, fluorescence imaging, and reconstitution assays, demonstrating that lipid droplets physically contact mitochondria in vivo and in vitro. Using a bimolecular fluorescence complementation assay in Saccharomyces cerevisiae, we generated an interactomic map of protein-protein contacts of lipid droplets with mitochondria and peroxisomes. The lipid droplet proteins Erg6 and Pet10 were found to be involved in 75% of the interactions detected. Interestingly, interactions between 3 pairs of lipid metabolic enzymes were detected. Collectively, these data demonstrate that lipid droplets make physical contacts with mitochondria and peroxisomes, and reveal specific molecular interactions that suggest active participation of lipid droplets in lipid metabolism in yeast.
越来越多的证据表明，脂滴作为一种中性脂质储存细胞器，通过与线粒体的相互作用，在脂质代谢和能量平衡中发挥作用。然而，这种相互作用的细胞功能和分子机制仍不清楚。在这里，我们通过透射电子显微镜、荧光成像和重建实验提供了数据，证明了脂滴在体内和体外与线粒体物理接触。我们利用酿酒酵母中的双分子荧光互补测定法，生成了脂滴与线粒体和过氧化物酶体相互作用的蛋白质-蛋白质互作图谱。脂滴蛋白 Erg6 和 Pet10 被发现参与了检测到的 75%的相互作用。有趣的是，还检测到了 3 对脂质代谢酶之间的相互作用。总的来说，这些数据表明脂滴与线粒体和过氧化物酶体发生物理接触，并揭示了特定的分子相互作用，表明脂滴在酵母的脂质代谢中积极参与。
