Mapping the interactome of HPV E6 and E7 oncoproteins with the ubiquitin‐proteasome system. (29th August 2017)

• Record Type: Journal Article
• Authors: Poirson, Juline; Biquand, Elise; Straub, Marie‐Laure; Cassonnet, Patricia; Nominé, Yves; Jones, Louis; van der Werf, Sylvie; Travé, Gilles; Zanier, Katia; Jacob, Yves; Demeret, Caroline; Masson, Murielle
• Is Part Of: FEBS journal. Volume 284:Number 19(2017)
• Page Start: 3171
• Page End: 3201
• Publication Date: 2017-08-29
• Subjects: HPV -- interactomic -- protein complementation assay -- ubiquitination; Biochemistry -- Periodicals; Molecular biology -- Periodicals; Pathology, Molecular -- Periodicals; 572
• DOI: 10.1111/febs.14193
• Languages: English
• ISSNs: 1742-464X

Abstract

Abstract : Protein ubiquitination and its reverse reaction, deubiquitination, regulate protein stability, protein binding activity, and their subcellular localization. These reactions are catalyzed by the enzymes E1, E2, and E3 ubiquitin (Ub) ligases and deubiquitinases (DUBs). The Ub‐proteasome system (UPS) is targeted by viruses for the sake of their replication and to escape host immune response. To identify novel partners of human papillomavirus 16 (HPV16) E6 and E7 proteins, we assembled and screened a library of 590 cDNAs related to the UPS by using the Gaussia princeps luciferase protein complementation assay. HPV16 E6 was found to bind to the homology to E6AP C terminus‐type Ub ligase (E6AP), three really interesting new gene (RING)‐type Ub ligases (MGRN1, LNX3, LNX4), and the DUB Ub‐specific protease 15 (USP15). Except for E6AP, the binding of UPS factors did not require the LxxLL‐binding pocket of HPV16 E6. LNX3 bound preferentially to all high‐risk mucosal HPV E6 tested, whereas LNX4 bound specifically to HPV16 E6. HPV16 E7 was found to bind to several broad‐complex tramtrack and bric‐a‐brac domain‐containing proteins (such as TNFAIP1/KCTD13) that are potential substrate adaptors of Cullin 3‐RING Ub ligases, to RING‐type Ub ligases implicated in innate immunity (RNF135, TRIM32, TRAF2, TRAF5), to the substrate adaptor DCAF15 of Cullin 4‐RING Ub ligase and to some DUBs (USP29, USP33). The binding to UPS factors did not require the LxCxE motif but rather the C‐terminal region of HPV16 E7 protein. The identified UPS factors interacted with most of E7 proteins across different HPV types. This study establishes a strategy for the rapid identification of interactions between host or pathogen proteins and the human ubiquitination system. Abstract : Ubiquitination and deubiquitination regulate protein stability, protein interactions and subcellular localization. Given its central role in cellular physiology, the Ub‐proteasome system (UPS) is targeted by viruses to enhance viral replication and to escape host immune responses. Murielle Masson and colleagues assembled and screened a library of 590 USP‐related cDNAs against human papillomavirus 16 E6 and E7 proteins using the Gaussia princeps luciferase protein complementation assay. This work identifies ubiquitin ligases and deubiquitinases targeted by E6 and E7, and establishes a strategy for the rapid identification host or pathogen proteins that interact with the human ubiquitination system.