Zhu H Y, Yamada H, Jiang Y M, Yamada M, Nishiyama Y
Laboratory of Virology, Research Institute for Disease Mechanism and Control, Nagoya University School of Medicine, Nagoya, Japan.
Arch Virol. 1999;144(10):1923-35. doi: 10.1007/s007050050715.
We studied intracellular localization of the UL31 protein of herpes simplex virus type 2 (HSV-2) in infected and transfected cells. The UL31 protein localized diffusely throughout the nucleus in infected Vero cells and the distribution patterns of the UL31 protein appeared to be different from those of either replication protein ICP8 or capsid protein ICP35. In transfected Vero cells it localized diffusely throughout the nucleus except the nucleolus at early times after transfection. At very low efficiency, it accumulated in the nucleolus. At intermediate times after transfection, the UL31 protein showed punctate staining in the nucleus. These punctate forms fused and became larger. At later times after transfection, granular forms further fused and a nuclear diffuse pattern virtually disappeared. We also constructed five N and C terminal deletion mutants of the UL31 protein for transfection assays and showed that the region containing amino acids 44 to 110 was important for nuclear and nucleolar localization. Moreover, green fluorescent protein (GFP)-targeting experiments showed that the UL31 protein was able to transport nonnuclear GFP to the nucleus and nucleolus as a fusion protein.
我们研究了单纯疱疹病毒2型（HSV-2）UL31蛋白在感染细胞和转染细胞中的细胞内定位。在感染的Vero细胞中，UL31蛋白弥漫性地定位于整个细胞核，其分布模式似乎与复制蛋白ICP8或衣壳蛋白ICP35的分布模式不同。在转染的Vero细胞中，转染后早期它弥漫性地定位于整个细胞核，但不包括核仁。在极低效率下，它会在核仁中积累。转染后的中间阶段，UL31蛋白在细胞核中呈现点状染色。这些点状形态融合并变大。转染后的后期，颗粒状形态进一步融合，核弥漫模式几乎消失。我们还构建了UL31蛋白的五个N端和C端缺失突变体用于转染实验，结果表明包含氨基酸44至110的区域对核定位和核仁定位很重要。此外，绿色荧光蛋白（GFP）靶向实验表明，UL31蛋白作为融合蛋白能够将非核GFP转运至细胞核和核仁。
