DNA methyltransferase DNMT3A associates with viral proteins and impacts HSV-1 infection. Author Daniell Rowles, Yuan-Chin Tsai, Todd Greco, Aaron Lin, Minghao Li, Justin Yeh, Ileana Cristea Publication Year 2015 Type Journal Article Abstract Viral infections can alter the cellular epigenetic landscape, through modulation of either DNA methylation profiles or chromatin remodeling enzymes and histone modifications. These changes can act to promote viral replication or host defense. Herpes simplex virus type 1 (HSV-1) is a prominent human pathogen, which relies on interactions with host factors for efficient replication and spread. Nevertheless, the knowledge regarding its modulation of epigenetic factors remains limited. Here, we used fluorescently-labeled viruses in conjunction with immunoaffinity purification and MS to study virus-virus and virus-host protein interactions during HSV-1 infection in primary human fibroblasts. We identified interactions among viral capsid and tegument proteins, detecting phosphorylation of the capsid protein VP26 at sites within its UL37-binding domain, and an acetylation within the major capsid protein VP5. Interestingly, we found a nuclear association between viral capsid proteins and the de novo DNA methyltransferase DNA (cytosine-5)-methyltransferase 3A (DNMT3A), which we confirmed by reciprocal isolations and microscopy. We show that drug-induced inhibition of DNA methyltransferase activity, as well as siRNA- and shRNA-mediated DNMT3A knockdowns trigger reductions in virus titers. Altogether, our results highlight a functional association of viral proteins with the mammalian DNA methyltransferase machinery, pointing to DNMT3A as a host factor required for effective HSV-1 infection. Keywords Animals, Humans, Phosphorylation, Cells, Cultured, Immunoblotting, Immunoprecipitation, Proteome, Fibroblasts, Virus Replication, Viral Proteins, Host-Pathogen Interactions, Herpesvirus 1, Human, Vero Cells, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization, Herpes Simplex, Capsid Proteins, Chlorocebus aethiops, DNA (Cytosine-5-)-Methyltransferases, DNA Methyltransferase 3A Journal Proteomics Volume 15 Issue 12 Pages 1968-82 Date Published 2015 Jun ISSN Number 1615-9861 DOI 10.1002/pmic.201500035 Alternate Journal Proteomics PMCID PMC4550099 PMID 25758154 PubMedPubMed CentralGoogle ScholarBibTeXEndNote X3 XML