ROS-induced HSP70 promotes cytoplasmic translocation of high-mobility group box 1b and stimulates antiviral autophagy in grass carp kidney cells
ROS-induced HSP70 promotes cytoplasmic translocation of high-mobility group box 1b and stimulates antiviral autophagy in grass carp kidney cells
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DOI：
10.1074/jbc.ra118.003840
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发表时间：
2018-11-09
影响因子：
4.8
通讯作者：
Su, Jianguo
中科院分区：
文献类型：
--
作者：
Rao, Youliang;Wan, Quanyuan;Su, Jianguo
自噬发挥许多生理和病理生理作用。然而，在硬骨鱼中，自噬在应对病毒感染中的作用和调节机制尚不清楚，例如草鱼（Ctenopharyngodon idella），它是中国最重要的水产养殖品种之一。在这项研究中，我们发现草鱼呼肠孤病毒（GCRV）感染和过氧化氢（H2O2）处理都会诱导草鱼肾细胞中活性氧（ROS）的积累并刺激自噬。用 N-乙酰基-L-半胱氨酸抑制 ROS 积累可显着抑制 GCRV 诱导的自噬激活并增强 GCRV 复制。尽管ROS诱导的自噬反过来限制了GCRV的复制，但进一步的研究表明，多功能细胞蛋白高迁移率族盒1b（HMGB1b）在草鱼中充当热休克蛋白70（HSP70）依赖性促自噬蛋白。 H2O2 处理后，细胞质 HSP70 易位到细胞核，与 HMGB1b 相互作用并促进 HMGB1b 的细胞质易位。过表达和 siRNA 介导的敲低实验表明，HSP70 和 HMGB1b 协同增强细胞质中 ROS 诱导的自噬激活。此外，HSP70 通过直接与 C. idella Beclin 1 相互作用，增强了 HMGB1b 与 Beclin 1 的 C. idella 直向同源物（自噬相关酵母蛋白 ATG6 的哺乳动物直向同源物）的关联。 总之，这项研究强调了 ROS 诱导的自噬响应 GCRV 感染的抗病毒功能，并揭示了 HSP70 在 HMGB1b 介导的自噬启动中的积极作用。硬骨鱼。
Autophagy plays many physiological and pathophysiological roles. However, the roles and the regulatory mechanisms of autophagy in response to viral infections are poorly defined in teleost fish, such as grass carp (Ctenopharyngodon idella), which is one of the most important aquaculture species in China. In this study, we found that both grass carp reovirus (GCRV) infection and hydrogen peroxide (H2O2) treatment induced the accumulation of reactive oxygen species (ROS) in C. idella kidney cells and stimulate autophagy. Suppressing ROS accumulation with N-acetyl-l-cysteine significantly inhibited GCRV-induced autophagy activation and enhanced GCRV replication. Although ROS-induced autophagy, in turn, restricted GCRV replication, further investigation revealed that the multifunctional cellular protein high-mobility group box 1b (HMGB1b) serves as a heat shock protein 70 (HSP70)-dependent, pro-autophagic protein in grass carp. Upon H2O2 treatment, cytoplasmic HSP70 translocated to the nucleus, where it interacted with HMGB1b and promoted cytoplasmic translocation of HMGB1b. Overexpression and siRNA-mediated knockdown assays indicated that HSP70 and HMGB1b synergistically enhance ROS-induced autophagic activation in the cytoplasm. Moreover, HSP70 reinforced an association of HMGB1b with the C. idella ortholog of Beclin 1 (a mammalian ortholog of the autophagy-associated yeast protein ATG6) by directly interacting with C. idella Beclin 1. In summary, this study highlights the antiviral function of ROS-induced autophagy in response to GCRV infection and reveals the positive role of HSP70 in HMGB1b-mediated autophagy initiation in teleost fish.