Restrictive influence of SAMHD1 on Hepatitis B Virus life cycle

• Type of Material: Article
• Authors: Andreas F. Sommer, Paul-Ehrlich-Institute; Lise Rivière, Paul-Ehrlich-Institute; Bingqian Qu, University Hospital Heidelberg; Kerstin Schott, Paul-Ehrlich-Institute; Maximilian Riess, Paul-Ehrlich-Institute; Yi Ni, University Hospital Heidelberg; Caitlin Shepard, Emory University; Esther Schnellbaecher, Paul-Ehrlich-Institute; Malin Finkernagel, Paul-Ehrlich-Institute; Kiyoshi Himmelsbach, Paul-Ehrlich-Institute; Karin Welzel, Paul-Ehrlich-Institute; Nadja Kettern, Paul-Ehrlich-Institute; Christian Donnerhak, Paul-Ehrlich-Institute; Carsten Münk, Heinrich Heine University Düsseldorf; Egbert Flory, Paul-Ehrlich-Institute; Juliane Liese, Goethe University Frankfurt; Baek Kim, Emory University; Stephan Urban, University Hospital Heidelberg; Renate König, Paul-Ehrlich-Institute
• Language: English
• Date: 2016-05-27
• Publisher: Nature Publishing Group
• Publication Version: Final Published Version
• Copyright Statement: © 2016, Macmillan Publishers Limited.
• License: Creative Commons Attribution 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1038/srep26616
• Title of Journal or Parent Work: Scientific Reports
• ISSN: 2045-2322
• Volume: 6
• Start Page: 26616
• End Page: 26616
• Grant/Funding Information: This project is supported by competitive funding by the Paul-Ehrlich-Institut to RK, by German Center for Infection Research “Deutsches Zentrum für Infektionsforschung (DZIF)” DZIF TTU 05.901, TTU 05.804, TTU 05.904, TTU 05.704 to SU and DZIF TTU 01.802, TTU 04.802, TTU 01.906 to RK and the NIH funding R01 GM104198 and R01 AI049781-01 to BK. CM is supported by the Heinz Ansmann Foundation.
• Keywords: PHOSPHORYLATION; INFECTION; ACID BINDING-PROTEIN; Hepatitis B virus; DNTPASE ACTIVITY; Innate immunity; CELLS; Science & Technology; REPLICATION; AICARDI-GOUTIERES SYNDROME; INHIBITION; NUCLEASE ACTIVITY; HIV-1 RESTRICTION; Multidisciplinary Sciences
• Research Categories: Biology, Virology; Health Sciences, General

Abstract

Deoxynucleotide triphosphates (dNTPs) are essential for efficient hepatitis B virus (HBV) replication. Here, we investigated the influence of the restriction factor SAMHD1, a dNTP hydrolase (dNTPase) and RNase, on HBV replication. We demonstrated that silencing of SAMHD1 in hepatic cells increased HBV replication, while overexpression had the opposite effect. SAMHD1 significantly affected the levels of extracellular viral DNA as well as intracellular reverse transcription products, without affecting HBV RNAs or cccDNA. SAMHD1 mutations that interfere with the dNTPase activity (D137N) or in the catalytic center of the histidine-aspartate (HD) domain (D311A), and a phospho-mimetic mutation (T592E), abrogated the inhibitory activity. In contrast, a mutation diminishing the potential RNase but not dNTPase activity (Q548A) and a mutation disabling phosphorylation (T592A) did not affect antiviral activity. Moreover, HBV restriction by SAMHD1 was rescued by addition of deoxynucleosides. Although HBV infection did not directly affect protein level or phosphorylation of SAMHD1, the virus upregulated intracellular dATPs. Interestingly, SAMHD1 was dephosphorylated, thus in a potentially antiviral-active state, in primary human hepatocytes. Furthermore, SAMHD1 was upregulated by type I and II interferons in hepatic cells. These results suggest that SAMHD1 is a relevant restriction factor for HBV and restricts reverse transcription through its dNTPase activity.