Rinck G, Birghan C, Harada T, Meyers G, Thiel H J, Tautz N
Institut für Virologie, FB Veterinärmedizin, Justus-Liebig-Universität Giessen, D-35392 Giessen, Germany.
J Virol. 2001 Oct;75(19):9470-82. doi: 10.1128/JVI.75.19.9470-9482.2001.
Pestiviruses are positive-strand RNA viruses closely related to human hepatitis C virus. Gene expression of these viruses occurs via translation of a polyprotein, which is further processed by cellular and viral proteases. Here we report the formation of a stable complex between an as-yet-undescribed cellular J-domain protein, a member of the DnaJ-chaperone family, and pestiviral nonstructural protein NS2. Accordingly, we termed the cellular protein Jiv, for J-domain protein interacting with viral protein. Jiv has the potential to induce in trans one specific processing step in the viral polyprotein, namely, cleavage of NS2-3. Efficient generation of its cleavage product NS3 has previously been shown to be obligatory for the cytopathogenicity of the pestiviruses. Regulated expression of Jiv in cells infected with noncytopathogenic bovine viral diarrhea virus disclosed a direct correlation between the intracellular level of Jiv, the extent of NS2-3 cleavage, and pestiviral cytopathogenicity.
瘟病毒是与人类丙型肝炎病毒密切相关的正链RNA病毒。这些病毒的基因表达通过多聚蛋白的翻译进行，多聚蛋白再由细胞和病毒蛋白酶进一步加工。在此，我们报道了一种尚未描述的细胞J结构域蛋白（DnaJ伴侣家族成员）与瘟病毒非结构蛋白NS2之间形成了稳定的复合物。因此，我们将该细胞蛋白命名为Jiv，即与病毒蛋白相互作用的J结构域蛋白。Jiv有可能在反式作用中诱导病毒多聚蛋白中的一个特定加工步骤，即NS2-3的切割。先前已表明，有效产生其切割产物NS3对瘟病毒的细胞致病性至关重要。在感染非细胞病变性牛病毒性腹泻病毒的细胞中，Jiv的调控表达揭示了Jiv的细胞内水平、NS2-3切割程度与瘟病毒细胞致病性之间的直接相关性。
