1t2k
From Proteopedia
Structure Of The DNA Binding Domains Of IRF3, ATF-2 and Jun Bound To DNA
Structural highlights
FunctionIRF3_HUMAN Key transcriptional regulator of type I interferon (IFN)-dependent immune responses and plays a critical role in the innate immune response against DNA and RNA viruses. Regulates the transcription of type I IFN genes (IFN-alpha and IFN-beta) and IFN-stimulated genes (ISG) by binding to an interferon-stimulated response element (ISRE) in their promoters. Acts as a more potent activator of the IFN-beta (IFNB) gene than the IFN-alpha (IFNA) gene and plays a critical role in both the early and late phases of the IFNA/B gene induction. Found in an inactive form in the cytoplasm of uninfected cells and following viral infection, double-stranded RNA (dsRNA), or toll-like receptor (TLR) signaling, becomes phosphorylated by IKBKE and TBK1 kinases. This induces a conformational change, leading to its dimerization and nuclear localization and association with CREB binding protein (CREBBP) to form dsRNA-activated factor 1 (DRAF1), a complex which activates the transcription of the type I IFN and ISG genes. Can activate distinct gene expression programs in macrophages and can induce significant apoptosis in primary macrophages. Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedTranscriptional activation of the interferon-beta (IFN-beta) gene requires assembly of an enhanceosome containing the transcription factors ATF-2/c-Jun, IRF-3/IRF-7, NF-kappaB and HMGI(Y). These factors cooperatively bind a composite DNA site and activate expression of the IFN-beta gene. The 3.0 A crystal structure of the DNA-binding domains of ATF-2/c-Jun and two IRF-3 molecules in a complex with 31 base pairs (bp) of the PRDIV-PRDIII region of the IFN-beta enhancer shows that association of the four proteins with DNA creates a continuous surface for the recognition of 24 bp. The structure, together with in vitro binding studies and protein mutagenesis, shows that protein-protein interactions are not critical for cooperative binding. Instead, cooperativity arises mainly through nucleotide sequence-dependent structural changes in the DNA that allow formation of complementary DNA conformations. Because the binding sites overlap on the enhancer, the unit of recognition is the entire nucleotide sequence, not the individual subsites. Crystal structure of ATF-2/c-Jun and IRF-3 bound to the interferon-beta enhancer.,Panne D, Maniatis T, Harrison SC EMBO J. 2004 Nov 10;23(22):4384-93. Epub 2004 Oct 28. PMID:15510218[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
| ||||||||||||||||||
