Goepfert P A, Shaw K L, Ritter G D, Mulligan M J
Department of Medicine, University of Alabama at Birmingham, 35294-2170, USA.
J Virol. 1997 Jan;71(1):778-84. doi: 10.1128/JVI.71.1.778-784.1997.
We recently identified an endoplasmic reticulum (ER) retrieval signal-the dilysine motif-in the glycoproteins of all five foamy viruses (FVs) for which sequences were available (P. A. Goepfert, G. Wang, and M. J. Mulligan, Cell 82:543-544, 1995). In the present study, expression of recombinant human FV (HFV) glycoprotein and analyses of oligosaccharide modifications and precursor cleavage indicated that the protein was localized to the ER. HFV glycoproteins encoding seven different dilysine motif mutations were then expressed. The results indicated that disruptions of the dilysine motif resulted in higher levels of forward transport of the HFV glycoprotein from the ER through the Golgi apparatus to the plasma membrane. We conclude that the dilysine motif is responsible for ER sorting of the FV glycoprotein. Signal-mediated ER localization has not previously been described for a retroviral glycoprotein.
我们最近在所有可获得序列的五种泡沫病毒（FV）的糖蛋白中鉴定出一种内质网（ER）回收信号——双赖氨酸基序（P. A. 戈普费特、G. 王和M. J. 马利根，《细胞》82:543 - 544，1995年）。在本研究中，重组人泡沫病毒（HFV）糖蛋白的表达以及寡糖修饰和前体切割分析表明该蛋白定位于内质网。随后表达了编码七种不同双赖氨酸基序突变的HFV糖蛋白。结果表明，双赖氨酸基序的破坏导致HFV糖蛋白从内质网经高尔基体向质膜的正向转运水平升高。我们得出结论，双赖氨酸基序负责FV糖蛋白的内质网分选。此前尚未有逆转录病毒糖蛋白通过信号介导定位于内质网的相关描述。
