PMID- 34488443 OWN - NLM STAT- MEDLINE DCOM- 20220119 LR - 20240403 IS - 2150-7511 (Electronic) VI - 12 IP - 5 DP - 2021 Oct 26 TI - The Ubiquitin Sensor and Adaptor Protein p62 Mediates Signal Transduction of a Viral Oncogenic Pathway. PG - e0109721 LID - 10.1128/mBio.01097-21 [doi] LID - e01097-21 AB - The Epstein-Barr virus (EBV) protein LMP1 serves as a paradigm that engages complicated ubiquitination-mediated mechanisms to activate multiple transcription factors. p62 is a ubiquitin sensor and a signal-transducing adaptor that has multiple functions in diverse contexts. However, the interaction between p62 and oncogenic viruses is poorly understood. We recently reported a crucial role for p62 in oncovirus-mediated oxidative stress by acting as a selective autophagy receptor. In this following pursuit, we further discovered that p62 is upregulated in EBV type 3 compared to type 1 latency, with a significant contribution from NF-kappaB and AP1 activities downstream of LMP1 signaling. In turn, p62 participates in LMP1 signal transduction through its interaction with TRAF6, promoting TRAF6 ubiquitination and activation. As expected, short hairpin RNA (shRNA)-mediated knockdown (KD) of p62 transcripts reduces LMP1-TRAF6 interaction and TRAF6 ubiquitination, as well as p65 nuclear translocation, which was assessed by Amnis imaging flow cytometry. Strikingly, LMP1-stimulated NF-kappaB, AP1, and Akt activities are all markedly reduced in p62(-/-) mouse embryo fibroblasts (MEFs) and in EBV-negative Burkitt's lymphoma (BL) cell lines with CRISPR-mediated knockout (KO) of the p62-encoding gene. However, EBV-positive BL cell lines (type 3 latency) with CRISPR-mediated KO of the p62-encoding gene failed to survive. In consequence, shRNA-mediated p62 KD impairs the ability of LMP1 to regulate its target gene expression, promotes etoposide-induced apoptosis, and reduces the proliferation of lymphoblastic cell lines (LCLs). These important findings have revealed a previously unrecognized novel role for p62 in EBV latency and oncogenesis, which advances our understanding of the mechanism underlying virus-mediated oncogenesis. IMPORTANCE As a ubiquitin sensor and a signal-transducing adaptor, p62 is crucial for NF-kappaB activation, which involves the ubiquitin machinery, in diverse contexts. However, whether p62 is required for EBV LMP1 activation of NF-kappaB is an open question. In this study, we provide evidence that p62 is upregulated in EBV type 3 latency and, in turn, p62 mediates LMP1 signal transduction to NF-kappaB, AP1, and Akt by promoting TRAF6 ubiquitination and activation. In consequence, p62 deficiency negatively regulates LMP1-mediated gene expression, promotes etoposide-induced apoptosis, and reduces the proliferation of LCLs. These important findings identified p62 as a novel signaling component of the key viral oncogenic signaling pathway. FAU - Wang, Ling AU - Wang L AUID- ORCID: 0000-0001-7861-2769 AD - Department of Internal Medicine, Quillen College of Medicine, East Tennessee State Universitygrid.255381.8, Johnson City, Tennessee, USA. AD - Center of Excellence for Inflammation, Infectious Diseases and Immunity, Quillen College of Medicine, East Tennessee State Universitygrid.255381.8, Johnson City, Tennessee, USA. FAU - Howell, Mary E A AU - Howell MEA AD - Department of Internal Medicine, Quillen College of Medicine, East Tennessee State Universitygrid.255381.8, Johnson City, Tennessee, USA. FAU - Sparks-Wallace, Ayrianna AU - Sparks-Wallace A AD - Department of Internal Medicine, Quillen College of Medicine, East Tennessee State Universitygrid.255381.8, Johnson City, Tennessee, USA. FAU - Zhao, Juan AU - Zhao J AD - Department of Internal Medicine, Quillen College of Medicine, East Tennessee State Universitygrid.255381.8, Johnson City, Tennessee, USA. AD - Center of Excellence for Inflammation, Infectious Diseases and Immunity, Quillen College of Medicine, East Tennessee State Universitygrid.255381.8, Johnson City, Tennessee, USA. FAU - Hensley, Culton R AU - Hensley CR AD - Department of Internal Medicine, Quillen College of Medicine, East Tennessee State Universitygrid.255381.8, Johnson City, Tennessee, USA. FAU - Nicksic, Camri A AU - Nicksic CA AD - Department of Internal Medicine, Quillen College of Medicine, East Tennessee State Universitygrid.255381.8, Johnson City, Tennessee, USA. FAU - Horne, Shanna R AU - Horne SR AD - Department of Internal Medicine, Quillen College of Medicine, East Tennessee State Universitygrid.255381.8, Johnson City, Tennessee, USA. FAU - Mohr, Kaylea B AU - Mohr KB AD - Department of Internal Medicine, Quillen College of Medicine, East Tennessee State Universitygrid.255381.8, Johnson City, Tennessee, USA. FAU - Moorman, Jonathan P AU - Moorman JP AD - Department of Internal Medicine, Quillen College of Medicine, East Tennessee State Universitygrid.255381.8, Johnson City, Tennessee, USA. AD - Center of Excellence for Inflammation, Infectious Diseases and Immunity, Quillen College of Medicine, East Tennessee State Universitygrid.255381.8, Johnson City, Tennessee, USA. AD - HCV/HIV Program, James H Quillen VA Medical Center, Johnson City, Tennessee, USA. FAU - Yao, Zhi Q AU - Yao ZQ AUID- ORCID: 0000-0002-1333-1007 AD - Department of Internal Medicine, Quillen College of Medicine, East Tennessee State Universitygrid.255381.8, Johnson City, Tennessee, USA. AD - Center of Excellence for Inflammation, Infectious Diseases and Immunity, Quillen College of Medicine, East Tennessee State Universitygrid.255381.8, Johnson City, Tennessee, USA. AD - HCV/HIV Program, James H Quillen VA Medical Center, Johnson City, Tennessee, USA. FAU - Ning, Shunbin AU - Ning S AUID- ORCID: 0000-0001-5484-5779 AD - Department of Internal Medicine, Quillen College of Medicine, East Tennessee State Universitygrid.255381.8, Johnson City, Tennessee, USA. AD - Center of Excellence for Inflammation, Infectious Diseases and Immunity, Quillen College of Medicine, East Tennessee State Universitygrid.255381.8, Johnson City, Tennessee, USA. LA - eng GR - R15 CA252986/CA/NCI NIH HHS/United States GR - S10 OD021572/OD/NIH HHS/United States GR - R15 DE029621/DE/NIDCR NIH HHS/United States GR - C06 RR030651/RR/NCRR NIH HHS/United States GR - R15 DE027314/DE/NIDCR NIH HHS/United States PT - Journal Article PT - Research Support, N.I.H., Extramural PT - Research Support, Non-U.S. Gov't DEP - 20210907 PL - United States TA - mBio JT - mBio JID - 101519231 RN - 0 (EBV-associated membrane antigen, Epstein-Barr virus) RN - 0 (NF-kappa B) RN - 0 (SQSTM1 protein, human) RN - 0 (Sequestosome-1 Protein) RN - 0 (Viral Matrix Proteins) SB - IM MH - Apoptosis MH - Carcinogenesis/genetics MH - Cell Line, Tumor MH - Cell Proliferation MH - Cell Transformation, Viral/genetics MH - *Gene Expression Regulation MH - Herpesvirus 4, Human/*genetics/*metabolism MH - Humans MH - NF-kappa B/*metabolism MH - Sequestosome-1 Protein/genetics/*metabolism MH - Signal Transduction MH - Viral Matrix Proteins/*genetics/metabolism MH - Virus Latency PMC - PMC8546576 OTO - NOTNLM OT - EBV OT - LMP1 OT - herpesviruses OT - p62 OT - ubiquitination OT - viral oncogenesis EDAT- 2021/09/08 06:00 MHDA- 2022/01/20 06:00 PMCR- 2021/09/07 CRDT- 2021/09/07 05:44 PHST- 2021/09/08 06:00 [pubmed] PHST- 2022/01/20 06:00 [medline] PHST- 2021/09/07 05:44 [entrez] PHST- 2021/09/07 00:00 [pmc-release] AID - mBio01097-21 [pii] AID - 10.1128/mBio.01097-21 [doi] PST - ppublish SO - mBio. 2021 Oct 26;12(5):e0109721. doi: 10.1128/mBio.01097-21. Epub 2021 Sep 7.