Department of Experimental Medical Science, Division of Diabetes, Metabolism and Endocrinology, Lund Univeristy , BMC C11, SE-221 84 Lund, Sweden.
J Proteome Res. 2012 Feb 3;11(2):1264-73. doi: 10.1021/pr200957p. Epub 2012 Jan 24.
Lipids are known to play a crucial role both in the normal control of insulin release and in the deterioration of β-cell function, as observed in type 2 diabetes. Despite this established dual role of lipids, little is known about lipid storage and handling in β-cells. Here, we isolated lipid droplets from oleate-incubated INS-1 832/13 cells and characterized the lipid droplet proteome. In a total of four rounds of droplet isolation and proteomic analysis by HPLC-MS/MS, we identified 96 proteins that were specific to droplets. The proteins fall into six categories based on function or previously observed localization: metabolism, endoplasmic reticulum/ribosomes, mitochondria, vesicle formation and transport, signaling, and miscellaneous. The protein profile reinforces the emerging picture of the lipid droplet as an active and dynamic organelle involved in lipid homeostasis and intracellular trafficking. Proteins belonging to the category mitochondria were highly represented, suggesting that the β-cell mitochondria and lipid droplets form a metabolic unit of potential relevance for insulin secretion.
脂质在胰岛素释放的正常控制和β细胞功能的恶化中起着至关重要的作用，这在 2 型糖尿病中得到了观察。尽管脂质具有这种双重作用，但关于β细胞中脂质的储存和处理知之甚少。在这里，我们从油酸盐孵育的 INS-1 832/13 细胞中分离了脂滴，并对脂滴蛋白质组进行了表征。在总共四轮的通过 HPLC-MS/MS 的液滴分离和蛋白质组学分析中，我们鉴定出了 96 种特异性的脂滴蛋白。这些蛋白质根据功能或先前观察到的定位分为六类：代谢、内质网/核糖体、线粒体、囊泡形成和运输、信号和杂项。蛋白质图谱强化了这样一个观点，即脂滴是一个活跃的、动态的细胞器，参与脂质稳态和细胞内运输。属于线粒体类别的蛋白质高度表达，表明β细胞的线粒体和脂滴形成了一个代谢单元，这可能与胰岛素分泌有关。
