柑橘鱼von Hippel-Lindau蛋白通过与IκB相互作用调控NF-κB信号通路，促进鱼类Ran病毒复制

Mandarin fish von Hippel-Lindau protein regulates the NF-κB signaling pathway via interaction with IκB to promote fish ranavirus replication

ZOOLOGICAL RESEARCH

影响因子:4.7

分区:生物学1区 Top / 动物学1区

发表日期:2024 Sep 18

作者: Zhi-Min Li, Xiao-Wei Qin, Qi Zhang, Jian He, Min-Cong Liang, Chuan-Rui Li, Yang Yu, Weng-Hui Liu, Shao-Ping Weng, Jian-Guo He, Chang-Jun Guo

DOI: 10.24272/j.issn.2095-8137.2023.392

摘要

von Hippel-Lindau（VHL）肿瘤抑制蛋白是一种E3泛素连接酶，作为氧感应途径的关键调控因子，用于靶向低氧诱导因子。近期证据表明哺乳动物VHL可能也在NF-κB信号通路中发挥关键作用，尽管其具体分子机制尚不明确。本文探讨了柑橘鱼（Siniperca chuatsi）VHL（scVHL）在NF-κB信号通路和柑橘鱼Ran病毒（MRV）复制中的作用。免疫刺激和MRV感染均诱导scVHL的转录，提示其可能在先天免疫中发挥作用。双荧光素酶报告基因检测和逆转录定量PCR（RT-qPCR）均显示scVHL激活并正向调控NF-κB信号通路。用NF-κB信号通路抑制剂处理表明，scVHL的作用可能通过scIKKα、scIKKβ、scIκBα或scp65介导。共免疫沉淀（Co-IP）分析发现scIκBα是scVHL的新的靶蛋白。此外，scVHL靶向scIκBα催化形成K63链接的多泛素链，从而激活NF-κB信号通路。MRV感染后，NF-κB信号持续活化，反过来促进MRV的复制。这些发现表明scVHL不仅正向调节NF-κB，还显著增强MRV的复制。该研究揭示了scVHL在鱼类中的NF-κB信号及病毒感染中的新功能。

Abstract

The von Hippel-Lindau tumor suppressor protein (VHL), an E3 ubiquitin ligase, functions as a critical regulator of the oxygen-sensing pathway for targeting hypoxia-inducible factors. Recent evidence suggests that mammalian VHL may also be critical to the NF-κB signaling pathway, although the specific molecular mechanisms remain unclear. Herein, the roles of mandarin fish ( Siniperca chuatsi) VHL ( scVHL) in the NF-κB signaling pathway and mandarin fish ranavirus (MRV) replication were explored. The transcription of scVHL was induced by immune stimulation and MRV infection, indicating a potential role in innate immunity. Dual-luciferase reporter gene assays and reverse transcription quantitative PCR (RT-qPCR) results demonstrated that scVHL evoked and positively regulated the NF-κB signaling pathway. Treatment with NF-κB signaling pathway inhibitors indicated that the role of scVHL may be mediated through scIKKα, scIKKβ, scIκBα, or scp65. Co-immunoprecipitation (Co-IP) analysis identified scIκBα as a novel target protein of scVHL. Moreover, scVHL targeted scIκBα to catalyze the formation of K63-linked polyubiquitin chains to activate the NF-κB signaling pathway. Following MRV infection, NF-κB signaling remained activated, which, in turn, promoted MRV replication. These findings suggest that scVHL not only positively regulates NF-κB but also significantly enhances MRV replication. This study reveals a novel function of scVHL in NF-κB signaling and viral infection in fish.