Ma Zicheng, Guo Lei, Ji Ran, Sun Zhe, Wang Jingyi, Yan Yang, Liu Kesen, Zhang Hanhua, Wang Xingya, Wu Chengyue, Lian Lin, Cao Wandi, Bai Juan, Jiang Ping, Liu Xing
Key Laboratory of Animal Diseases Diagnostic and Immunology, Ministry of Agriculture, MOE International Joint Collaborative Research Laboratory for Animal Health & Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China.
College of Life Sciences, Nanjing Agricultural University, Nanjing, China.
J Virol. 2025 Sep 2:e0097425. doi: 10.1128/jvi.00974-25.
Programmed cell death (PCD) refers to a regulated cellular process involving a cascade of biochemical reactions and molecular mechanisms, commonly including apoptosis, necroptosis, and pyroptosis. Ferroptosis is a recently identified form of PCD distinguished by its dependence on iron. Emerging evidence underscores the significance of ferroptosis in viral infections; however, its role in Pseudorabies virus (PRV) infection, an enveloped double-stranded DNA virus belonging to the Alphaherpesvirinae subfamily, remains poorly understood. Here, we demonstrate that PRV infection induces multiple forms of PCD, including ferroptosis, which is characterized by mitochondrial shrinkage, lipid peroxidation, ferrous iron (Fe²) accumulation, and elevated levels of reactive oxygen species (ROS). Ferroptosis facilitates PRV replication, with iron overload playing a crucial role. Mechanistically, we show that transferrin receptor 1 (TfR1) and ferritinophagy are involved in PRV-induced iron overload. Specifically, PRV infection upregulates TfR1 expression via hypoxia-inducible factor-1β (HIF-1β) and promotes its translocation to the cell membrane through Rab11a, thereby enhancing the cellular import of extracellular ferric iron (Fe³). In parallel, PRV activates ferritinophagy to degrade ferritin heavy chain 1 (FTH1) via selective autophagy receptors, nuclear receptor coactivator 4 (NCOA4) and Tax1-binding protein 1 (TAX1BP1), further contributing to intracellular iron accumulation. Altogether, these findings demonstrate that PRV induces ferroptosis by disrupting iron homeostasis through TfR1 activation and ferritinophagy induction, providing novel insights into the pathogenesis of PRV and other herpesviruses.IMPORTANCEFerroptosis is an iron-dependent form of non-apoptotic cell death that primarily involves iron overload, lipid peroxidation, and suppression of antioxidant systems. Increasing evidence indicates that ferroptosis plays an important role in viral infections. In this study, we show that PRV induces ferroptosis by disrupting iron homeostasis through TfR1 activation and ferritinophagy induction. On one hand, PRV infection upregulates TfR1 expression through HIF-1β and facilitates TfR1 translocation to the cell membrane via Rab11a, leading to enhanced import of extracellular Fe into cells. On the other hand, PRV exploits the selective autophagy receptors NCOA4 and TAX1BP1, which strengthens the interaction between NCOA4, TAX1BP1, and FTH1, triggering ferritinophagy and increasing intracellular Fe levels. Collectively, these findings enrich the understanding of the mechanism by which PRV induces ferroptosis, shedding new light on PRV and other alpha-herpesvirus infections.
程序性细胞死亡（PCD）是指一个受调控的细胞过程，涉及一系列生化反应和分子机制，通常包括凋亡、坏死性凋亡和焦亡。铁死亡是最近发现的一种程序性细胞死亡形式，其特点是依赖铁。越来越多的证据强调了铁死亡在病毒感染中的重要性；然而，其在伪狂犬病病毒（PRV）感染中的作用仍知之甚少，PRV是一种属于α疱疹病毒亚科的包膜双链DNA病毒。在这里，我们证明PRV感染可诱导多种形式的程序性细胞死亡，包括铁死亡，其特征为线粒体收缩、脂质过氧化、亚铁（Fe²）积累以及活性氧（ROS）水平升高。铁死亡促进PRV复制，铁过载起着关键作用。机制上，我们表明转铁蛋白受体1（TfR1）和铁蛋白自噬参与PRV诱导的铁过载。具体而言，PRV感染通过缺氧诱导因子-1β（HIF-1β）上调TfR1表达，并通过Rab11a促进其向细胞膜的转运，从而增强细胞对细胞外铁离子（Fe³）的摄取。同时，PRV通过选择性自噬受体核受体辅激活因子4（NCOA4）和Tax1结合蛋白1（TAX1BP1）激活铁蛋白自噬以降解铁蛋白重链1（FTH1），进一步导致细胞内铁积累。总之，这些发现表明PRV通过激活TfR1和诱导铁蛋白自噬破坏铁稳态来诱导铁死亡，为PRV和其他疱疹病毒的发病机制提供了新的见解。
重要性
铁死亡是一种非凋亡性细胞死亡的铁依赖性形式，主要涉及铁过载、脂质过氧化和抗氧化系统的抑制。越来越多的证据表明铁死亡在病毒感染中起重要作用。在本研究中，我们表明PRV通过激活TfR1和诱导铁蛋白自噬破坏铁稳态来诱导铁死亡。一方面，PRV感染通过HIF-1β上调TfR1表达，并通过Rab11a促进TfR1向细胞膜的转运，导致细胞外铁向细胞内的摄取增加。另一方面，PRV利用选择性自噬受体NCOA4和TAX1BP1，加强NCOA4、TAX1BP1与FTH1之间的相互作用，触发铁蛋白自噬并增加细胞内铁水平。总的来说，这些发现丰富了对PRV诱导铁死亡机制的理解，为PRV和其他α疱疹病毒感染提供了新的线索。
