Interferon-stimulated response element (ISRE)-binding protein complex DRAF1 is activated in Sindbis virus (HR)-infected cells.
To elucidate the host cell defense mechanisms in response to Sindbis viral infection, we have started to characterize interferon (IFN)-stimulated response element (ISRE)-binding proteins activated in infected cells that are involved in the transcriptional induction of IFN type I-inducible genes. Using electromobility shift assays (EMSA), we detected several protein complexes with a human IFN-stimulated gene 15 (ISG15) ISRE in extracts from virus-infected L929 cells that were absent in extracts from uninfected cells. Comigration with Newcastle disease virus-activated ISRE-binding complexes, ISRE-binding specificity, supershift experiments, and conditions of formation indicate that the complexes activated by Sindbis viral infection in L929 cells correspond to DRAF1 and ISG factor 3 (ISGF3). Transfection of L929 cells with poly rI:rC induced only ISGF3. DRAF1 could be detected in Sindbis virus-infected mouse embryo fibroblasts derived from IFNR type I and type II KO mice. Viral RNA synthesis is required for activation of DRAF1.
Behr
M
M
Institute for Virology and Immunology, University of Würzburg, 97078 Würzburg, Germany.
Schieferdecker
K
K
Bühr
P
P
Büter
M
M
Petsophonsakul
W
W
Sirirungsi
W
W
Redmann-Müller
I
I
Müller
U
U
Prempracha
N
N
Jungwirth
C
C
D000818:Animals; D002460:Cell Line; D002522:Chlorocebus aethiops; D016207:Cytokines / Q000096:biosynthesis / Q000235:genetics; D004268:DNA-Binding Proteins / Q000378:metabolism*; D003609:Dactinomycin / Q000494:pharmacology; D024202:Electrophoretic Mobility Shift Assay; D007370:Interferon Type I / Q000494:pharmacology*; D046911:Macromolecular Substances; D051379:Mice; D019384:Nucleic Acid Synthesis Inhibitors / Q000494:pharmacology; D012330:RNA, Double-Stranded / Q000494:pharmacology; D012333:RNA, Messenger / Q000096:biosynthesis; D012367:RNA, Viral / Q000096:biosynthesis; D020218:Response Elements; D012845:Sindbis Virus / Q000235:genetics / Q000502:physiology*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D015533:Transcriptional Activation; D014452:Ubiquitins; D014709:Vero Cells
D016207:Cytokines; D004268:DNA-Binding Proteins; C110908:DRAF1 transcription factor; C489550:G1p2 protein, mouse; D007370:Interferon Type I; D046911:Macromolecular Substances; D019384:Nucleic Acid Synthesis Inhibitors; D012330:RNA, Double-Stranded; D012333:RNA, Messenger; D012367:RNA, Viral; D014157:Transcription Factors; D014452:Ubiquitins; D003609:Dactinomycin