Zhu Yinxing, Song Yanhua, Kumar Dilip, Jackson Peter K, Prasad B V Venkataram, Ding Siyuan
Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, MO, USA.
Department of Microbiology and Immunology, Stanford School of Medicine, Stanford, CA, USA.
Nat Commun. 2025 Aug 29;16(1):8083. doi: 10.1038/s41467-025-63393-3.
Timely induction of interferons and interferon-stimulated genes (ISGs) is critical for successful host defense against viral infections. VP3 encoded by rotavirus is implicated in interferon antagonism. However, the precise mechanisms remain incompletely understood. By conducting tandem-affinity purification coupled with high-resolution mass spectrometry, we identify the prefoldin complex as the top cellular binding partner of VP3. Rotavirus infection is significantly enhanced in prefoldin subunit knockout cells. Using proteome-wide label-free quantification, we find that prefoldin assists in folding ubiquitin-like-modifier-activating-enzyme-3 (UBA3), both of which positively regulate ISG expression. Through direct and competitive binding, VP3 interferes with the chaperone activity of prefoldin, leading to unstable UBA3, reduces IRF9, and suppresses ISG transcription. Our findings report a novel function of a prefoldin-UBA3-IRF9-ISG axis in antiviral immunity and uncover new aspects of virus-host interactions that could be exploited for broad-spectrum antiviral therapeutic development.
及时诱导干扰素和干扰素刺激基因（ISGs）对于宿主成功抵御病毒感染至关重要。轮状病毒编码的VP3与干扰素拮抗作用有关。然而，其确切机制仍未完全清楚。通过进行串联亲和纯化并结合高分辨率质谱分析，我们确定预折叠蛋白复合体是VP3在细胞内的首要结合伴侣。在预折叠蛋白亚基敲除细胞中，轮状病毒感染显著增强。通过全蛋白质组无标记定量分析，我们发现预折叠蛋白有助于泛素样修饰激活酶3（UBA3）的折叠，二者均正向调节ISG的表达。通过直接和竞争性结合，VP3干扰预折叠蛋白的伴侣活性，导致UBA3不稳定，减少IRF9，并抑制ISG转录。我们的研究结果揭示了预折叠蛋白-UBA3-IRF9-ISG轴在抗病毒免疫中的新功能，并揭示了病毒-宿主相互作用的新方面，这些方面可用于广谱抗病毒治疗的开发。
