Duck hepatitis A virus 1-encoded 2B protein disturbs ion and organelle homeostasis to promote NF-κB/NLRP3-mediated inflammatory response
Sai Mao, Xinghong Liu, Dandan Wu, Zhilong Zhang, Di Sun, Xumin Ou, Juan Huang, Ying Wu, Qiao Yang, Bin Tian, Shun Chen, Mafeng Liu, Dekang Zhu, Shaqiu Zhang, Xinxin Zhao, Yu He, Zhen Wu, Renyong Jia, Mingshu Wang, Anchun Cheng
Abstract
Previous studies by our group and others have highlighted the critical role of hyperinflammation in the pathogenicity of duck hepatitis A virus 1 (DHAV-1), an avian picornavirus that has caused significant devastation in the duck industry worldwide for decades. However, the precise mechanisms by which DHAV-1 infection regulates the inflammatory responses, particularly the production of IL-1β, remain poorly understood. In this study, we demonstrate that DHAV-1 infection triggers NF-κB- and NLRP3 inflammasome-mediated IL-1β production. Mechanistically, DHAV-1 infection, particularly its replication and translation, disrupts cellular homeostasis of Ca 2+ , K + , ROS and cathepsin, which act cooperatively as assembly signals for NLRP3 inflammasome activation. By screening DHAV-1-encoded proteins, we identified that the viroporin 2B dominates NF-κB as well as NLRP3 inflammasome activation. Mutation analysis revealed that I43 within the 2B protein is the key amino acid for Ca 2+ mobilization and subsequent activation of NF-κB transcriptional activity and NLRP3 inflammasome. Moreover, DHAV-1 infection and the 2B protein activate the MAVS- and MyD88-NF-κB pathways by relay, providing the necessary priming signals for NLRP3 inflammasome activation. In summary, our findings elucidate a mechanism through which DHAV-1 triggers inflammatory responses via NF-κB/NLRP3 inflammasome activation, offering new perspectives on DHAV-1 pathogenesis and informing the development of targeted anti-DHAV-1 treatments. • Duck hepatitis A virus 1 (DHAV-1) drives NF-κB and NLRP3 inflammasome activation to induce hyperinflammatory responses via the cooperation of cellular disorder of Ca 2+ , K + , ROS and cathepsin. • DHAV-1-encoding 2B protein is sufficient to provide priming and assembly signals for NLRP3 inflammasome activation. • The activity of the 2B protein in elevating cytosolic Ca 2+ levels is necessary to activate NF-κB transcriptional activity, NLRP3 inflammasome activation, and the subsequent IL-1β production. • I43 is the key amino acid of 2B protein for the mobilization of Ca 2+ and NF-κB/NLRP3 inflammasome activation.