Two distinct alpha-interferon-dependent signal transduction pathways may contribute to activation of transcription of the guanylate-binding protein gene.

Published

Journal Article

The promoter of the gene encoding a cytoplasmic guanylate-binding protein (GBP) contains two overlapping elements: the interferon stimulation response element (ISRE), which mediates alpha interferon (IFN-alpha)-dependent transcription, and the IFN-gamma activation site (GAS), which is required for IFN-gamma-mediated stimulation. The ISRE binds a factor called ISGF-3 that is activated by IFN-alpha but not by IFN-gamma. The GAS binds a protein that is activated by IFN-gamma, which we have termed GAF (IFN-gamma activation factor; T. Decker, D. J. Lew, J. Mirkovitch, and J. E. Darnell, Jr., EMBO J., in press; D. J. Lew, T. Decker, I. Strehlow, and J. E. Darnell, Jr., Mol. Cell. Biol. 11:182-191, 1991). We now find that the GAS is also an IFN-alpha-responsive element in vivo and that IFN-alpha (in addition to activating ISGF-3) rapidly activates a GAS-binding factor, the IFN-alpha activation factor (AAF). The AAF has characteristics very similar to those of the previously described GAF. Through the use of inhibitors of protein synthesis and inhibitors of protein kinases, the activation conditions of AAF, GAF, and ISGF-3 could be distinguished. Therefore, not only do IFN-alpha and IFN-gamma stimulate transcription of GBP through different receptors linked to different signaling molecules, but occupation of the IFN-alpha receptor apparently leads to the rapid activation of two different DNA-binding proteins through the use of different intracellular pathways.

Full Text

Duke Authors

Cited Authors

  • Decker, T; Lew, DJ; Darnell, JE

Published Date

  • October 1991

Published In

Volume / Issue

  • 11 / 10

Start / End Page

  • 5147 - 5153

PubMed ID

  • 1833631

Pubmed Central ID

  • 1833631

International Standard Serial Number (ISSN)

  • 0270-7306

Digital Object Identifier (DOI)

  • 10.1128/mcb.11.10.5147

Language

  • eng

Conference Location

  • United States