Fat-specific protein 27, a novel lipid droplet protein that enhances triglyceride storage
Fat-specific protein 27, a novel lipid droplet protein that enhances triglyceride storage
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DOI：
10.1074/jbc.m707404200
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发表时间：
2007-11-23
影响因子：
4.8
通讯作者：
Czech, Michael P.
中科院分区：
文献类型：
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作者：
Puri, Vishwajeet;Konda, Silvana;Czech, Michael P.
脂肪特异性蛋白 (FSP)27/Cidec 在白色和棕色脂肪组织中表达最高，并且在脂肪生成过程中丰度增加 50 倍以上。然而，自从 15 年前被发现以来，它在脂肪细胞中的功能仍然难以捉摸。在这里，我们证明 FSP27/Cidec 定位于培养脂肪细胞中的脂滴，并具有促进脂质积累的功能。异位表达的 FSP27-GFP 围绕 3T3-L1 脂肪细胞中的脂滴，并与已知的脂滴蛋白 perilipin 共定位。 3T3-L1 脂肪细胞中内源性 FSP27 的免疫染色也证实了其在脂滴上的存在。 FSP27-GFP 表达还显着增加脂滴大小并增强 3T3-L1 前脂肪细胞以及其他细胞类型（如 COS 细胞）中总中性脂质的积累。相反，成熟脂肪细胞中基于 RNA 干扰的 FSP27/Cidec 消耗显着刺激脂肪分解并减小脂滴的大小。这些数据表明 FSP27/Cidec 是一种新型脂肪细胞脂滴蛋白，可负向调节脂肪分解并促进甘油三酯积累。
Fat-specific protein (FSP)27/Cidec is most highly expressed in white and brown adipose tissues and increases in abundance by over 50-fold during adipogenesis. However, its function in adipocytes has remained elusive since its discovery over 15 years ago. Here we demonstrate that FSP27/Cidec localizes to lipid droplets in cultured adipocytes and functions to promote lipid accumulation. Ectopically expressed FSP27-GFP surrounds lipid droplets in 3T3-L1 adipocytes and colocalizes with the known lipid droplet protein perilipin. Immunostaining of endogenous FSP27 in 3T3-L1 adipocytes also confirmed its presence on lipid droplets. FSP27-GFP expression also markedly increases lipid droplet size and enhances accumulation of total neutral lipids in 3T3-L1 preadipocytes as well as other cell types such as COS cells. Conversely, RNA interference-based FSP27/Cidec depletion in mature adipocytes significantly stimulates lipolysis and reduces the size of lipid droplets. These data reveal FSP27/Cidec as a novel adipocyte lipid droplet protein that negatively regulates lipolysis and promotes triglyceride accumulation.