STUB1 is targeted by the SUMO-interacting motif of EBNA1 to maintain Epstein-Barr Virus latency

Yuyan Wang; Shujuan Du; Caixia Zhu; Chong Wang; Nuoya Yu; Ziqi Lin; Jin Gan; Yi Guo; Xinxin Huang; Yuping He; Erle Robertson; Di Qu; Fang Wei; Qiliang Cai

doi:10.1371/journal.ppat.1008447

STUB1 is targeted by the SUMO-interacting motif of EBNA1 to maintain Epstein-Barr Virus latency

PLoS Pathog. 2020 Mar 16;16(3):e1008447. doi: 10.1371/journal.ppat.1008447. eCollection 2020 Mar.

Authors

Yuyan Wang¹, Shujuan Du¹, Caixia Zhu¹, Chong Wang¹, Nuoya Yu¹, Ziqi Lin¹, Jin Gan^{1

2}, Yi Guo³, Xinxin Huang⁴, Yuping He⁴, Erle Robertson⁵, Di Qu¹, Fang Wei², Qiliang Cai^{1

6}

Affiliations

¹ MOE&NHC&CAMS Key Laboratory of Medical Molecular Virology, Department of Medical Microbiology and Parasitology, Biosafety Level 3 Laboratory, School of Basic Medical Science, Shanghai Medical College, Fudan University, Shanghai, P. R. China.
² ShengYushou Center of Cell Biology and Immunology, School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai, P. R. China.
³ Department of Gynecology, Key laboratory of AIDS immunology of Ministry of Health, First Affiliated Hospital of China Medical University, Shengyang, P. R. China.
⁴ Technical Center For Animal, Plant and Food Inspection and Quarantine of Shanghai Customs, Shanghai, P. R. China.
⁵ Department of Otorhinolaryngology-Head and Neck surgery, Department of Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America.
⁶ Expert Workstation, Baoji Central Hospital, Baoji, P. R. China.

Abstract

Latent Epstein-Barr virus (EBV) infection is strongly associated with several malignancies, including B-cell lymphomas and epithelial tumors. EBNA1 is a key antigen expressed in all EBV-associated tumors during latency that is required for maintenance of the EBV episome DNA and the regulation of viral gene transcription. However, the mechanism utilized by EBV to maintain latent infection at the levels of posttranslational regulation remains largely unclear. Here, we report that EBNA1 contains two SUMO-interacting motifs (SIM2 and SIM3), and mutation of SIM2, but not SIM3, dramatically disrupts the EBNA1 dimerization, while SIM3 contributes to the polySUMO2 modification of EBNA1 at lysine 477 in vitro. Proteomic and immunoprecipitation analyses further reveal that the SIM3 motif is required for the EBNA1-mediated inhibitory effects on SUMO2-modified STUB1, SUMO2-mediated degradation of USP7, and SUMO1-modified KAP1. Deletion of the EBNASIM motif leads to functional loss of both EBNA1-mediated viral episome maintenance and lytic gene silencing. Importantly, hypoxic stress induces the SUMO2 modification of EBNA1, and in turn the dissociation of EBNA1 with STUB1, KAP1 and USP7 to increase the SUMO1 modification of both STUB1 and KAP1 for reactivation of lytic replication. Therefore, the EBNA1SIM motif plays an essential role in EBV latency and is a potential therapeutic target against EBV-associated cancers.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Amino Acid Motifs
Cell Line
Epstein-Barr Virus Nuclear Antigens / genetics
Epstein-Barr Virus Nuclear Antigens / metabolism*
Herpesvirus 4, Human / physiology*
Humans
Small Ubiquitin-Related Modifier Proteins / genetics
Small Ubiquitin-Related Modifier Proteins / metabolism*
Tripartite Motif-Containing Protein 28 / genetics
Tripartite Motif-Containing Protein 28 / metabolism
Ubiquitin-Protein Ligases / genetics
Ubiquitin-Protein Ligases / metabolism*
Ubiquitin-Specific Peptidase 7 / genetics
Ubiquitin-Specific Peptidase 7 / metabolism
Virus Latency / physiology*

Substances

Epstein-Barr Virus Nuclear Antigens
SUMO2 protein, human
Small Ubiquitin-Related Modifier Proteins
STUB1 protein, human
TRIM28 protein, human
Tripartite Motif-Containing Protein 28
Ubiquitin-Protein Ligases
USP7 protein, human
Ubiquitin-Specific Peptidase 7
EBV-encoded nuclear antigen 1

Grants and funding

This work was supported by the National Key Research and Development Program of China (2019ZX09721001 to DQ), and the Research Program on Biosafety Guarantee Technology of High-level Biosafety Laboratory and Important Pathogen Laboratory (2018ZX10734401-004 to DQ), and the National Natural Science Foundation of China (81672015, 81971930 to QC; 81772166 to FW, 81572054 to YG), and QC is a scholar of New Century Excellent Talents in University of China. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript