Ryu S W, Kim E
Research Center for Biomedicinal Resources and Division of Life Science, PaiChai University, 439-6 Doma-dong, Seo-gu, Taejon, 302-735, South Korea.
Biochem Biophys Res Commun. 2001 Sep 7;286(5):1027-32. doi: 10.1006/bbrc.2001.5505.
FAF1 is a Fas-binding protein without typical death domain. Instead, FAF1 has several domains found in proteins of ubiquitination pathway. Transient overexpression of hFAF1 in BOSC23 cells caused membrane blebbing and cell body condensation which were characteristics of apoptosis. Subsequent analysis revealed that overexpression of hFAF1 induced nuclear condensation, appearance of phosphatidylserines in the outer leaflet of the cellular membrane, and caspase 3 activation. The apoptotic potential of hFAF1 required downstream ubiquitin homologous domain (UB2) and adjacent nuclear localization signal but not the Fas-binding domain. Our data showed that mere intrinsic overexpression of hFAF1 initiated apoptosis in the absence of any extrinsic death signal in BOSC23 cells.
FAF1是一种没有典型死亡结构域的Fas结合蛋白。相反，FAF1具有泛素化途径蛋白中发现的几个结构域。在BOSC23细胞中瞬时过表达hFAF1会导致细胞膜起泡和细胞体浓缩，这是细胞凋亡的特征。随后的分析表明，hFAF1的过表达诱导了核浓缩、细胞膜外小叶中磷脂酰丝氨酸的出现以及半胱天冬酶3的激活。hFAF1的凋亡潜能需要下游泛素同源结构域（UB2）和相邻的核定位信号，但不需要Fas结合结构域。我们的数据表明，在BOSC23细胞中，仅hFAF1的内在过表达就能在没有任何外源性死亡信号的情况下引发细胞凋亡。
