| First Author | Contursi C | Year | 2000 |
| Journal | Proc Natl Acad Sci U S A | Volume | 97 |
| Issue | 1 | Pages | 91-6 |
| PubMed ID | 10618376 | Mgi Jnum | J:127061 |
| Mgi Id | MGI:3762723 | Doi | 10.1073/pnas.97.1.91 |
| Citation | Contursi C, et al. (2000) IFN consensus sequence binding protein potentiates STAT1-dependent activation of IFNgamma-responsive promoters in macrophages. Proc Natl Acad Sci U S A 97(1):91-6 |
| abstractText | IFNgamma, once called the macrophage-activating factor, stimulates many genes in macrophages, ultimately leading to the elicitation of innate immunity. IFNgamma's functions depend on the activation of STAT1, which stimulates transcription of IFNgamma-inducible genes through the GAS element. The IFN consensus sequence binding protein (icsbgamma or IFN regulatory factor 8), encoding a transcription factor of the IFN regulatory factor family, is one of such IFNgamma-inducible genes in macrophages. We found that macrophages from ICSBP-/- mice were defective in inducing some IFNgamma-responsive genes, even though they were capable of activating STAT1 in response to IFNgamma. Accordingly, IFNgamma activation of luciferase reporters fused to the GAS element was severely impaired in ICSBP-/- macrophages, but transfection of ICSBP resulted in marked stimulation of these reporters. Consistent with its role in activating IFNgamma-responsive promoters, ICSBP stimulated reporter activity in a GAS-specific manner, even in the absence of IFNgamma treatment, and in STAT1 negative cells. Indicative of a mechanism for this stimulation, DNA affinity binding assays revealed that endogenous ICSBP was recruited to a multiprotein complex that bound to GAS. These results suggest that ICSBP, when induced by IFNgamma through STAT1, in turn generates a second wave of transcription from GAS-containing promoters, thereby contributing to the elicitation of IFNgamma's unique activities in immune cells. |
