Type-I-IFN-Stimulated Gene TRIM5γ Inhibits HBV Replication by Promoting HBx Degradation

Publication date: 10 December 2019Source: Cell Reports, Volume 29, Issue 11Author(s): Guangyun Tan, Zhaohong Yi, Hongxiao Song, Fengchao Xu, Feng Li, Roghiyh Aliyari, Hong Zhang, Peishuang Du, Yanhua Ding, Junqi Niu, Xiaosong Wang, Lishan Su, F. Xiao-Feng Qin, Genhong ChengSummaryTo understand the molecular mechanisms that mediate the anti-hepatitis B virus (HBV) effect of interferon (IFN) therapy, we conduct high-throughput bimolecular fluorescence complementation screening to identify potential physical interactions between the HBx protein and 145 IFN-stimulated genes (ISGs). Seven HBx-interacting ISGs have consistent and significant inhibitory effects on HBV replication, among which TRIM5γ suppresses HBV replication by promoting K48-linked ubiquitination and degradation of the HBx protein on the K95 ubiquitin site. The B-Box domain of TRIM5γ under overexpression conditions is sufficient to trigger HBx degradation and is responsible both for interacting with HBx and recruiting TRIM31, which is an ubiquitin ligase that triggers HBx ubiquitination. High expression levels of TRIM5γ in IFN-α-treated HBV patients might indicate a better therapeutic effect. Thus, our studies identify a crucial role for TRIM5γ and TRIM31 in promoting HBx degradation, which may facilitate the development of therapeutic agents for the treatment of patients with IFN-resistant HBV infection.Graphical Abstract
Source: Cell Reports - Category: Cytology Source Type: research