Solé Marieta, Perkins Edward M, Frisancho Augusto, Huang Eugene, Desai Prashant
Viral Oncology Program, The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, 353 CRB 1, 1650 Orleans Street, The Johns Hopkins University, Baltimore, MD 21231, USA.
J Virol. 2007 Aug;81(15):8367-70. doi: 10.1128/JVI.00819-07. Epub 2007 May 23.
The herpes simplex virus (HSV) triplex is a complex of three protein subunits, VP19C and a dimer of VP23 that is essential for capsid assembly. We have derived HSV-1 recombinant viruses that contain monomeric red fluorescent protein (mRFP1), a Flu hemagglutinin (HA) epitope, and a six-histidine tag fused to the amino terminus of VP19C. These viruses were capable of growth on Vero cells, indicating that the amino terminus of VP19C could tolerate these fusions. By use of immunoelectron microscopy methods, capsids that express VP19C-mRFP but not VP19C-HA were labeled with gold particles when incubated with the corresponding antibody. Our conclusion from the data is that a large tag at the N terminus of VP19C was sufficiently exposed on the capsid surface for polyclonal antibody reactivity, while the small HA epitope was inaccessible to the antibody. These data indicate that an epitope tag at the amino terminus of VP19C is not exposed at the capsid surface for reactivity to its antibody.
单纯疱疹病毒（HSV）三聚体是由三个蛋白质亚基组成的复合物，即VP19C和VP23二聚体，它们对衣壳组装至关重要。我们构建了含有单体红色荧光蛋白（mRFP1）、流感血凝素（HA）表位以及与VP19C氨基末端融合的六个组氨酸标签的HSV-1重组病毒。这些病毒能够在Vero细胞上生长，这表明VP19C的氨基末端能够耐受这些融合。通过免疫电子显微镜方法，当与相应抗体孵育时，表达VP19C-mRFP而非VP19C-HA的衣壳会被金颗粒标记。我们从这些数据得出的结论是，VP19C氨基末端的大标签在衣壳表面充分暴露，可与多克隆抗体发生反应，而小的HA表位则无法被抗体识别。这些数据表明，VP19C氨基末端的表位标签在衣壳表面并未暴露，无法与针对它的抗体发生反应。
