Department of Medical Laboratory Science and Biotechnology, China Medical University, Taichung, Taiwan; Institute of Molecular Biology, National Chung Hsing University, Taichung, Taiwan.
Proteomics. 2012 Nov;12(21):3193-205. doi: 10.1002/pmic.201200225. Epub 2012 Oct 5.
Severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV) papain-like protease (PLpro), a deubiquitinating enzyme, demonstrates inactivation of interferon (IFN) regulatory factor 3 and NF-κB, reduction of IFN induction, and suppression of type I IFN signaling pathway. This study investigates cytokine expression and proteomic change induced by SARS-CoV PLpro in human promonocyte cells. PLpro significantly increased TGF-β1 mRNA expression (greater than fourfold) and protein production (greater than threefold). Proteomic analysis, Western blot, and quantitative real-time PCR assays indicated PLpro upregulating TGF-β1-associated genes: HSP27, protein disulfide isomerase A3 precursor, glial fibrillary acidic protein, vimentin, retinal dehydrogenase 2, and glutathione transferase omega-1. PLpro-activated ubiquitin proteasome pathway via upregulation of ubiquitin-conjugating enzyme E2-25k and proteasome subunit alpha type 5. Proteasome inhibitor MG-132 significantly reduced expression of TGF-β1 and vimentin. PLpro upregulated HSP27, linking with activation of p38 MAPK and ERK1/2 signaling. Treatment with SB203580 and U0126 reduced PLpro-induced expression of TGF-β1, vimentin, and type I collagen. Results point to SARS-CoV PLpro triggering TGF-β1 production via ubiquitin proteasome, p38 MAPK, and ERK1/2-mediated signaling.
严重急性呼吸综合征（SARS）冠状病毒（SARS-CoV）木瓜蛋白酶样蛋白酶（PLpro）是一种去泛素化酶，可使干扰素（IFN）调节因子 3 和 NF-κB 失活，减少 IFN 的诱导，并抑制 I 型 IFN 信号通路。本研究探讨了 SARS-CoV PLpro 在人原单核细胞中诱导的细胞因子表达和蛋白质组变化。PLpro 显著增加 TGF-β1 mRNA 表达（四倍以上）和蛋白产生（三倍以上）。蛋白质组分析、Western blot 和定量实时 PCR 检测表明，PLpro 上调了 TGF-β1 相关基因：HSP27、蛋白二硫键异构酶 A3 前体、胶质纤维酸性蛋白、波形蛋白、视网膜脱氢酶 2 和谷胱甘肽转移酶ω-1。PLpro 通过上调泛素结合酶 E2-25k 和蛋白酶体亚基 alpha 类型 5 激活泛素蛋白酶体途径。蛋白酶体抑制剂 MG-132 显著降低了 TGF-β1 和波形蛋白的表达。PLpro 上调了 HSP27，与 p38 MAPK 和 ERK1/2 信号的激活有关。用 SB203580 和 U0126 处理可降低 PLpro 诱导的 TGF-β1、波形蛋白和 I 型胶原的表达。结果表明，SARS-CoV PLpro 通过泛素蛋白酶体、p38 MAPK 和 ERK1/2 介导的信号通路触发 TGF-β1 的产生。
