Section of Endocrinology, Diabetes and Nutrition, Department of Medicine, Boston University School of Medicine, 650 Albany Street, Boston, MA 02118, USA.
Biochem Biophys Res Commun. 2013 Mar 8;432(2):296-301. doi: 10.1016/j.bbrc.2013.01.113. Epub 2013 Feb 8.
Human adipocytes express high levels of two distinct lipid droplet proteins, fat specific protein 27 (FSP27; also called CIDEC), a member of the CIDE family, and perilipin1 (PLIN1), a member of the PAT family. Both proteins play a role in fat metabolism in adipocytes, but how they interact is not known. Our present study demonstrates that FSP27 and PLIN1 co-localize and interact in cultured human primary adipocytes. We also found that the C-terminal domain of FSP27, aa 120-220, interacts with PLIN1. Individual expression of exogenous FSP27 or PLIN1 increased triglyceride content and decreased glycerol release (a measure of lipolysis), but co-expression of both proteins did not further increase triglyceride content or decrease lipolysis in human adipocytes. However, the combination of PLIN1 and FSP27 increased the average size of lipid droplets or caused the formation of unilocular adipocytes. Our data suggest that FSP27 interacts with PLIN1 to regulate lipid droplet size in human adipocytes in a concerted manner.
人脂肪细胞表达高水平的两种不同的脂滴蛋白，脂肪特异性蛋白 27（FSP27；也称为 CIDEC），CIDEC 家族的一员，和 perilipin1（PLIN1），PAT 家族的一员。这两种蛋白在脂肪细胞的脂肪代谢中发挥作用，但它们如何相互作用尚不清楚。我们目前的研究表明，FSP27 和 PLIN1 在培养的人原代脂肪细胞中共定位和相互作用。我们还发现，FSP27 的 C 端结构域（aa120-220）与 PLIN1 相互作用。外源性表达 FSP27 或 PLIN1 均可增加甘油三酯含量并减少甘油释放（脂肪分解的一种衡量指标），但在人脂肪细胞中共表达两种蛋白并不能进一步增加甘油三酯含量或减少脂肪分解。然而，PLIN1 和 FSP27 的组合增加了脂滴的平均大小或导致形成单房性脂肪细胞。我们的数据表明，FSP27 以协调的方式与 PLIN1 相互作用来调节人脂肪细胞中脂滴的大小。
