TY - JOUR
T1 - Mutual antagonism between the ebola virus VP35 protein and the RIG-I activator PACT determines infection outcome
AU - Luthra, Priya
AU - Ramanan, Parameshwaran
AU - Mire, Chad E.
AU - Weisend, Carla
AU - Tsuda, Yoshimi
AU - Yen, Benjamin
AU - Liu, Gai
AU - Leung, Daisy W.
AU - Geisbert, Thomas W.
AU - Ebihara, Hideki
AU - Amarasinghe, Gaya K.
AU - Basler, Christopher F.
N1 - Funding Information:
The work was supported in part by NIH grants AI059536 and AI093786 to C.F.B.; NIH grant AI081914 to G.K.A.; and the Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, USA. Monoclonal antibodies against EBOV VP35 and EBOV NP were generated in collaboration with the Mount Sinai Hybridoma Shared Research Facility. We thank Ganes Sen (Lerner Research Institute, Cleveland Clinic) for providing PACT knockout MEFs, Qinghua Liu (UT Southwestern, Dallas) for PACT cDNA, and Adolfo García-Sastré (Mount Sinai School of Medicine) for providing the RIG-I expression plasmid. We thank Reed S. Shabman for assistance in setting up the minigenome assays and Juyoung Huh (WUSM), Krystle Agans (UTMB), and Kwabena Bonsu (MSSM) for excellent technical support.
PY - 2013/7/17
Y1 - 2013/7/17
N2 - The cytoplasmic pattern recognition receptor RIG-I is activated by viral RNA and induces type I IFN responses to control viral replication. The cellular dsRNA binding protein PACT can also activate RIG-I. To counteract innate antiviral responses, some viruses, including Ebola virus (EBOV), encode proteins that antagonize RIG-I signaling. Here, we show that EBOV VP35 inhibits PACT-induced RIG-I ATPase activity in a dose-dependent manner. The interaction of PACT with RIG-I is disrupted by wild-type VP35, but not by VP35 mutants that are unable to bind PACT. In addition, PACT-VP35 interaction impairs the association between VP35 and the viral polymerase, thereby diminishing viral RNA synthesis and modulating EBOV replication. PACT-deficient cells are defective in IFN induction and are insensitive to VP35 function. These data support a model in which the VP35-PACT interaction is mutually antagonistic and plays a fundamental role in determining the outcome of EBOV infection.
AB - The cytoplasmic pattern recognition receptor RIG-I is activated by viral RNA and induces type I IFN responses to control viral replication. The cellular dsRNA binding protein PACT can also activate RIG-I. To counteract innate antiviral responses, some viruses, including Ebola virus (EBOV), encode proteins that antagonize RIG-I signaling. Here, we show that EBOV VP35 inhibits PACT-induced RIG-I ATPase activity in a dose-dependent manner. The interaction of PACT with RIG-I is disrupted by wild-type VP35, but not by VP35 mutants that are unable to bind PACT. In addition, PACT-VP35 interaction impairs the association between VP35 and the viral polymerase, thereby diminishing viral RNA synthesis and modulating EBOV replication. PACT-deficient cells are defective in IFN induction and are insensitive to VP35 function. These data support a model in which the VP35-PACT interaction is mutually antagonistic and plays a fundamental role in determining the outcome of EBOV infection.
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U2 - 10.1016/j.chom.2013.06.010
DO - 10.1016/j.chom.2013.06.010
M3 - Article
C2 - 23870315
AN - SCOPUS:84880445500
SN - 1931-3128
VL - 14
SP - 74
EP - 84
JO - Cell Host and Microbe
JF - Cell Host and Microbe
IS - 1
ER -