Direct Triggering of the Type I Interferon System by Virus Infection: Activation of a Transcription Factor Complex Containing IRF-3 and CBP/p300
Overview
Molecular Biology
Affiliations
It has been hypothesized that certain viral infections directly activate a transcription factor(s) which is responsible for the activation of genes encoding type I interferons (IFNs) and interferon-stimulated genes (ISGs) via interferon regulatory factor (IRF) motifs present in their respective promoters. These events trigger the activation of defense machinery against viruses. Here we demonstrate that IRF-3 transmits a virus-induced signal from the cytoplasm to the nucleus. In unstimulated cells, IRF-3 is present in its inactive form, restricted to the cytoplasm due to a continuous nuclear export mediated by nuclear export signal, and it exhibits few DNA-binding properties. Virus infection but not IFN treatment induces phosphorylation of IRF-3 on specific serine residues, thereby allowing it to complex with the co-activator CBP/p300 with simultaneous nuclear translocation and its specific DNA binding. We also show that a dominant-negative mutant of IRF-3 could inhibit virus-induced activation of chromosomal type I IFN genes and ISGs. These findings suggest that IRF-3 plays an important role in the virus-inducible primary activation of type I IFN and IFN-responsive genes.
cGAS-STING targeting offers therapy choice in lung diseases.
Wang Y, Zhang X, Wang W, Zhang Y, Fleishman J, Wang H Biol Direct. 2025; 20(1):20.
PMID: 39920718 PMC: 11806777. DOI: 10.1186/s13062-025-00611-4.
Shinde O, Boyer J, Cambier S, VanPortfliet J, Sui X, Yadav G Immunity. 2025; 58(1):59-73.e5.
PMID: 39765229 PMC: 11735300. DOI: 10.1016/j.immuni.2024.12.002.
Role of Interferon Regulatory Factor 1 in acute and chronic virus infections.
Rahlf C, Tarakanova V Virology. 2025; 603:110386.
PMID: 39754861 PMC: 11788042. DOI: 10.1016/j.virol.2024.110386.
Novel risk loci for COVID-19 hospitalization among admixed American populations.
Diz-de Almeida S, Cruz R, Luchessi A, Lorenzo-Salazar J, de Heredia M, Quintela I Elife. 2024; 13.
PMID: 39361370 PMC: 11449485. DOI: 10.7554/eLife.93666.
In Vitro and In Vivo Evaluation of Virus-Induced Innate Immunity in Mouse.
Wang Z, Hu P, Shan X, Wang B, Xiong H, Yu Q Methods Mol Biol. 2024; 2854:237-251.
PMID: 39192134 DOI: 10.1007/978-1-0716-4108-8_23.