Gao Qiang, Binns Derk D, Kinch Lisa N, Grishin Nick V, Ortiz Natalie, Chen Xiao, Goodman Joel M
Department of Pharmacology, University of Texas Southwestern Medical School, Dallas, TX.
Howard Hughes Medical Institute, University of Texas Southwestern Medical School, Dallas, TX.
J Cell Biol. 2017 Oct 2;216(10):3199-3217. doi: 10.1083/jcb.201610013. Epub 2017 Aug 11.
Pet10p is a yeast lipid droplet protein of unknown function. We show that it binds specifically to and is stabilized by droplets containing triacylglycerol (TG). Droplets isolated from cells with a deletion strongly aggregate, appear fragile, and fuse in vivo when cells are cultured in oleic acid. Pet10p binds early to nascent droplets, and their rate of appearance is decreased in Moreover, Pet10p functionally interacts with the endoplasmic reticulum droplet assembly factors seipin and Fit2 to maintain proper droplet morphology. The activity of Dga1p, a diacylglycerol acyltransferase, and TG accumulation were both 30-35% lower in the absence of Pet10p. Pet10p contains a PAT domain, a defining property of perilipins, which was not previously known to exist in yeast. We propose that the core functions of Pet10p and other perilipins extend beyond protection from lipases and include the preservation of droplet integrity as well as collaboration with seipin and Fit2 in droplet assembly and maintenance.
Pet10p是一种功能未知的酵母脂滴蛋白。我们发现它能特异性结合含有三酰甘油（TG）的脂滴并在其作用下得以稳定。从缺失该蛋白的细胞中分离出的脂滴会强烈聚集，看起来很脆弱，且当细胞在油酸中培养时会在体内融合。Pet10p能早期结合新生脂滴，在[此处原文缺失相关信息]中其出现速率会降低。此外，Pet10p在功能上与内质网脂滴组装因子seipin和Fit2相互作用，以维持脂滴的正常形态。在没有Pet10p的情况下，二酰甘油酰基转移酶Dga1p的活性和TG积累均降低了30 - 35%。Pet10p含有一个PAT结构域，这是围脂滴蛋白的一个标志性特征，此前在酵母中并不为人所知。我们认为Pet10p和其他围脂滴蛋白的核心功能不仅限于防止脂肪酶的作用，还包括保持脂滴的完整性以及在脂滴组装和维持过程中与seipin和Fit2协同作用。
