Toronto General Research Institute, University Health Network, Toronto, Ontario, Canada.
J Interferon Cytokine Res. 2012 Mar;32(3):127-37. doi: 10.1089/jir.2011.0100. Epub 2012 Jan 26.
In earlier studies we provided evidence that vaccinia virus (VACV) phosphorylation-activation of host cell signaling effectors is critical for subsequent viral replication. In this report, using mass spectrometry-based proteomics, we have identified 387 host cell proteins that co-immunoprecipitate with VACV in infected, permissive PM1.CCR5 human T cells. Among these, glomulin was distinguishable based on its known interaction with a tyrosine kinase receptor, c-Met, its ability to become tyrosine-phosphorylated, and its association with signaling effectors. siRNA knockdown of glomulin expression in PM1.CCR5 T cells reduces VACV infection. Glomulin interacts with the inactive, nonphosphorylated form of c-MET. We demonstrate that treatment of PM1.CCR5 T cells with a c-Met phosphorylation inhibitor leads to a significant reduction in VACV infectivity. Additionally, inhibition of phosphorylation of c-Met abrogates VACV-inducible phosphorylation of Erk 1/2 and IRS-2, signaling effectors identified as critical for VACV infection. These data identify glomulin as a permissivity factor for VACV infection and as a potential therapeutic target for inhibition of VACV infection.
在早期的研究中，我们提供了证据表明，痘苗病毒（VACV）对宿主细胞信号效应物的磷酸化激活对于随后的病毒复制至关重要。在本报告中，我们使用基于质谱的蛋白质组学方法，鉴定了 387 种宿主细胞蛋白，这些蛋白在感染的、允许的 PM1.CCR5 人 T 细胞中与 VACV 共同免疫沉淀。在这些蛋白中，根据其与酪氨酸激酶受体 c-Met 的已知相互作用、能够被酪氨酸磷酸化的能力以及与信号效应物的关联，glomulin 是可区分的。在 PM1.CCR5 T 细胞中使用 siRNA 敲低 glomulin 表达会降低 VACV 感染。Glomulin 与非磷酸化的 c-MET 相互作用。我们证明，用 c-Met 磷酸化抑制剂处理 PM1.CCR5 T 细胞会导致 VACV 感染性显著降低。此外，抑制 c-Met 的磷酸化会阻断 VACV 诱导的 Erk 1/2 和 IRS-2 的磷酸化，这两种信号效应物被确定为 VACV 感染所必需的。这些数据将 glomulin 鉴定为 VACV 感染的许可因子，并鉴定为抑制 VACV 感染的潜在治疗靶标。
