title: Characterization of the elements and proteins responsible for interferon-stimulated gene induction by human cytomegalovirus.
abstract: Human cytomegalovirus (HCMV) infection of human fibroblast cells activates a large number of interferon-stimulated genes (ISGs) in a viral envelope-cell membrane fusion-dependent mechanism. In this study, we identified two interferon response elements, the interferon-stimulated response element (ISRE) and the gamma interferon-activated site (GAS), which act as HCMV response sites (VRS). Gel mobility shift assays showed that cellular proteins form specific and identical complexes with ISRE and GAS elements, and the binding of these complexes to ISRE and GAS is stimulated by HCMV infection. Point mutations in the consensus sequences of ISRE and GAS completely abolished their activities in response to HCMV-mediated transactivation, as well as their abilities to interact with HCMV-activated VRS-binding proteins. Interferon regulatory factor 3 does not appear to be present in the VRS-binding complexes or to be involved directly in HCMV-mediated ISG activation. Using ProteinChip technology, four potential proteins were identified, ranging from 20 to 42 kDa, in the VRS-binding complexes. The data suggest that HCMV infection activates VRS-binding proteins, which then bind to the VRS and stimulate ISG expression.
authors.affiliation: Department of Microbiology and Molecular Genetics, UMDNJ-New Jersey Medical School, 225 Warren St., Newark, NJ 07101-1709, USA.
authors.forename: Shaojun
authors.initials: S
authors.lastname: Yang
authors.forename: James
authors.initials: J
authors.lastname: Netterwald
authors.forename: Weijia
authors.initials: W
authors.lastname: Wang
authors.forename: Hua
authors.initials: H
authors.lastname: Zhu
mesh_terms: D001483:Base Sequence; D002478:Cells, Cultured; D003587:Cytomegalovirus / Q000235:genetics* / Q000276:immunology; D004268:DNA-Binding Proteins / Q000235:genetics / Q000276:immunology; D005347:Fibroblasts / Q000821:virology; D015967:Gene Expression Regulation, Viral / Q000276:immunology*; D017930:Genes, Reporter; D004854:Herpesvirus 4, Human / Q000235:genetics; D006801:Humans; D007231:Infant, Newborn; D050838:Interferon Regulatory Factor-3; D007372:Interferons / Q000494:pharmacology*; D008156:Luciferases / Q000235:genetics; D008297:Male; D016297:Mutagenesis, Site-Directed; D010957:Plasmids; D017354:Point Mutation; D014157:Transcription Factors / Q000235:genetics / Q000276:immunology; D015533:Transcriptional Activation
chemical_list: D004268:DNA-Binding Proteins; C494232:IRF3 protein, human; D050838:Interferon Regulatory Factor-3; D014157:Transcription Factors; D007372:Interferons; D008156:Luciferases